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Tai F, Zhai R, Ding K, Zhang Y, Yang H, Li H, Wang Q, Cao Z, Ge C, Fu H, Xiao F, Zheng X. Long non‑coding RNA lung cancer‑associated transcript 1 regulates ferroptosis via microRNA‑34a‑5p‑mediated GTP cyclohydrolase 1 downregulation in lung cancer cells. Int J Oncol 2024; 64:64. [PMID: 38757341 PMCID: PMC11095600 DOI: 10.3892/ijo.2024.5652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 04/09/2024] [Indexed: 05/18/2024] Open
Abstract
Ferroptosis, a recently discovered type of programmed cell death triggered by excessive accumulation of iron‑dependent lipid peroxidation, is linked to several malignancies, including non‑small cell lung cancer. Long non‑coding RNAs (lncRNAs) are involved in ferroptosis; however, data on their role and mechanism in cancer therapy remains limited. Therefore, the aim of the present study was to identify ferroptosis‑associated mRNAs and lncRNAs in A549 lung cancer cells treated with RAS‑selective lethal 3 (RSL3) and ferrostatin‑1 (Fer‑1) using RNA sequencing. The results demonstrated that lncRNA lung cancer‑associated transcript 1 (LUCAT1) was significantly upregulated in lung adenocarcinoma and lung squamous cell carcinoma tissues. Co‑expression analysis of differentially expressed mRNAs and lncRNAs suggested that LUCAT1 has a crucial role in ferroptosis. LUCAT1 expression was markedly elevated in A549 cells treated with RSL3, which was prevented by co‑incubation with Fer‑1. Functionally, overexpression of LUCAT1 facilitated cell proliferation and reduced the occurrence of ferroptosis induced by RSL3 and Erastin, while inhibition of LUCAT1 expression reduced cell proliferation and increased ferroptosis. Mechanistically, downregulation of LUCAT1 resulted in the downregulation of both GTP cyclohydrolase 1 (GCH1) and ferroptosis suppressor protein 1 (FSP1). Furthermore, inhibition of LUCAT1 expression upregulated microRNA (miR)‑34a‑5p and then downregulated GCH1. These results indicated that inhibition of LUCAT1 expression promoted ferroptosis by modulating the downregulation of GCH1, mediated by miR‑34a‑5p. Therefore, the combination of knocking down LUCAT1 expression with ferroptosis inducers may be a promising strategy for lung cancer treatment.
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Affiliation(s)
- Fumin Tai
- Department of Experimental Hematology and Biochemistry, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P.R. China
| | - Rui Zhai
- Department of Experimental Hematology and Biochemistry, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P.R. China
| | - Kexin Ding
- Department of Experimental Hematology and Biochemistry, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P.R. China
| | - Yaocang Zhang
- Department of Experimental Hematology and Biochemistry, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P.R. China
| | - Hexi Yang
- Department of Experimental Hematology and Biochemistry, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P.R. China
| | - Hujie Li
- Department of Experimental Hematology and Biochemistry, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P.R. China
| | - Qiong Wang
- Department of Experimental Hematology and Biochemistry, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P.R. China
| | - Zhengyue Cao
- Department of Experimental Hematology and Biochemistry, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P.R. China
| | - Changhui Ge
- Department of Experimental Hematology and Biochemistry, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P.R. China
| | - Hanjiang Fu
- Department of Experimental Hematology and Biochemistry, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P.R. China
| | - Fengjun Xiao
- Department of Experimental Hematology and Biochemistry, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P.R. China
| | - Xiaofei Zheng
- Department of Experimental Hematology and Biochemistry, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, P.R. China
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2
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Jung-Klawitter S, Richter P, Yuan Y, Welzel K, Kube M, Bähr S, Leibner A, Flory E, Opladen T. Tyrosine hydroxylase variants influence protein expression, cellular localization, stability, enzymatic activity and the physical interaction between tyrosine hydroxylase and GTP cyclohydrolase 1. J Inherit Metab Dis 2024; 47:517-532. [PMID: 38084654 DOI: 10.1002/jimd.12690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 10/17/2023] [Accepted: 11/03/2023] [Indexed: 05/16/2024]
Abstract
Tyrosine hydroxylase (TH) is the rate-limiting enzyme in dopamine biosynthesis catalyzing the tetrahydrobiopterin (BH4)-dependent hydroxylation of tyrosine to L-DOPA. Here, we analyzed 25 TH variants associated with various degrees of dopa-responsive dystonia and evaluate the effect of each variant on protein stability, activity and cellular localization. Furthermore, we investigated the physical interaction between TH and human wildtype (wt) GTP cyclohydrolase 1 (GTPCH) and the effect of variants on this interaction. Our in vitro results classify variants according to their resistance to proteinase K digestion into three groups (stable, intermediate, unstable). Based on their cellular localization, two groups of variants can be identified, variant group one with cytoplasmic distribution and variant group two forming aggregates. These aggregates do not correlate with loss of enzymatic activity but nevertheless might be a good target for molecular chaperones. Unfortunately, no obvious correlation between the half-life of a variant and its enzymatic activity or between solubility, stability and enzymatic activity of a given variant could be found. Excitingly, some variants disrupt the physical interaction between TH and human wildtype GTPCH, thereby interfering with enzymatic activity and offering new druggable targets for therapy. Taken together, our results highlight the importance of an in-depth molecular analysis of each variant in order to be able to classify groups of disease variants and to find specific therapies for each subgroup. Stand-alone in silico analyses predict less precise the effect of specific variants and should be combined with other in vitro analyses in cellular model systems.
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Affiliation(s)
- Sabine Jung-Klawitter
- Medical Faculty, Center for Child and Adolescent Medicine, Pediatric Clinic I, Section of Neuropediatrics and Metabolic Medicine, Heidelberg University, Heidelberg, Germany
| | - Petra Richter
- Medical Faculty, Center for Child and Adolescent Medicine, Pediatric Clinic I, Section of Neuropediatrics and Metabolic Medicine, Heidelberg University, Heidelberg, Germany
| | - Yuheng Yuan
- Medical Faculty, Center for Child and Adolescent Medicine, Pediatric Clinic I, Section of Neuropediatrics and Metabolic Medicine, Heidelberg University, Heidelberg, Germany
| | - Karin Welzel
- Division of Hematology, Cell and Gene Therapy, Paul-Ehrlich-Institute, Langen, Germany
| | - Marie Kube
- Institute of Molecular Biology, Mainz, Germany
| | - Stella Bähr
- Medical Faculty, Center for Child and Adolescent Medicine, Pediatric Clinic I, Section of Neuropediatrics and Metabolic Medicine, Heidelberg University, Heidelberg, Germany
| | - Alexander Leibner
- Medical Faculty, Center for Child and Adolescent Medicine, Pediatric Clinic I, Section of Neuropediatrics and Metabolic Medicine, Heidelberg University, Heidelberg, Germany
| | - Egbert Flory
- Division of Hematology, Cell and Gene Therapy, Paul-Ehrlich-Institute, Langen, Germany
| | - Thomas Opladen
- Medical Faculty, Center for Child and Adolescent Medicine, Pediatric Clinic I, Section of Neuropediatrics and Metabolic Medicine, Heidelberg University, Heidelberg, Germany
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3
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Wang Z, Zhang N, Zhang M, Jiang Y, Ng AS, Bridges E, Zhang W, Zeng X, Luo Q, Liang J, Győrffy B, Hublitz P, Liang Z, Fischer R, Kerr D, Harris AL, Cai S. GTP Cyclohydrolase Drives Breast Cancer Development and Promotes EMT in an Enzyme-Independent Manner. Cancer Res 2023; 83:3400-3413. [PMID: 37463466 DOI: 10.1158/0008-5472.can-22-3471] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 04/27/2023] [Accepted: 07/14/2023] [Indexed: 07/20/2023]
Abstract
GTP cyclohydrolase (GCH1) is the rate-limiting enzyme for tetrahydrobiopterin (BH4) biosynthesis. The catalysis of BH4 biosynthesis is tightly regulated for physiological neurotransmission, inflammation, and vascular tone. Paradoxically, BH4 has emerged as an oncometabolite regulating tumor growth, but the effects on tumor development remain controversial. Here, we found that GCH1 potentiated the growth of triple-negative breast cancer (TNBC) and HER2+ breast cancer and transformed nontumor breast epithelial cells. Independent of BH4 production, GCH1 protein induced epithelial-to-mesenchymal transition by binding to vimentin (Vim), which was mediated by HSP90. Conversely, GCH1 ablation impaired tumor growth, suppressed Vim in TNBC, and inhibited EGFR/ERK signaling while activating the p53 pathway in estrogen receptor-positive tumor cells. GCH1 deficiency increases tumor cell sensitivity to HSP90 inhibition and endocrine treatments. In addition, high GCH1 correlated with poor breast cancer survival. Together, this study reveals an enzyme-independent oncogenic role of GCH1, presenting it as a potential target for therapeutic development. SIGNIFICANCE GTP cyclohydrolase functions as an oncogene in breast cancer and binds vimentin to induce epithelial-to-mesenchymal transition independently of its enzyme activity, which confers targetable vulnerabilities for developing breast cancer treatment strategies.
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Affiliation(s)
- Zijing Wang
- Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
- Sichuan University-Oxford University Huaxi Joint Centre for Gastrointestinal Cancer, West China Hospital, Sichuan University, Chengdu, China
| | - Nan Zhang
- Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
- Sichuan University-Oxford University Huaxi Joint Centre for Gastrointestinal Cancer, West China Hospital, Sichuan University, Chengdu, China
| | - Miao Zhang
- Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
- School of Acupuncture and Moxibustion, Fujian University of Traditional Chinese Medicine, China
| | - Yao Jiang
- Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Aik Seng Ng
- Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Esther Bridges
- Molecular Oncology Laboratories, University Department of Oncology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Wei Zhang
- Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Xin Zeng
- Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Qi Luo
- Xiamen Cancer Hospital, Xiamen First Hospital, Xiamen University, Fujian, China
| | - Jiabien Liang
- Xiamen Cancer Hospital, Xiamen First Hospital, Xiamen University, Fujian, China
| | - Balázs Győrffy
- TTK Cancer Biomarker Research Group, Institute of Enzymology, and Semmelweis University Department Bioinformatics and Department of Paediatrics, Budapest, Hungary
| | - Philip Hublitz
- Genome Engineering Facility, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Zhu Liang
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Roosevelt Drive, Oxford, United Kingdom
| | - Roman Fischer
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Roosevelt Drive, Oxford, United Kingdom
| | - David Kerr
- Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Adrian L Harris
- Molecular Oncology Laboratories, University Department of Oncology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Shijie Cai
- Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
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4
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Chuaiphichai S, Chu SM, Carnicer R, Kelly M, Bendall JK, Simon JN, Douglas G, Crabtree MJ, Casadei B, Channon KM. Endothelial cell-specific roles for tetrahydrobiopterin in myocardial function, cardiac hypertrophy, and response to myocardial ischemia-reperfusion injury. Am J Physiol Heart Circ Physiol 2023; 324:H430-H442. [PMID: 36735402 PMCID: PMC9988535 DOI: 10.1152/ajpheart.00562.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 12/15/2022] [Accepted: 12/31/2022] [Indexed: 02/04/2023]
Abstract
The cofactor tetrahydrobiopterin (BH4) is a critical regulator of nitric oxide synthase (NOS) function and redox signaling, with reduced BH4 implicated in multiple cardiovascular disease states. In the myocardium, augmentation of BH4 levels can impact on cardiomyocyte function, preventing hypertrophy and heart failure. However, the specific role of endothelial cell BH4 biosynthesis in the coronary circulation and its role in cardiac function and the response to ischemia has yet to be elucidated. Endothelial cell-specific Gch1 knockout mice were generated by crossing Gch1fl/fl with Tie2cre mice, generating Gch1fl/flTie2cre mice and littermate controls. GTP cyclohydrolase protein and BH4 levels were reduced in heart tissues from Gch1fl/flTie2cre mice, localized to endothelial cells, with normal cardiomyocyte BH4. Deficiency in coronary endothelial cell BH4 led to NOS uncoupling, decreased NO bioactivity, and increased superoxide and hydrogen peroxide productions in the hearts of Gch1fl/flTie2cre mice. Under physiological conditions, loss of endothelial cell-specific BH4 led to mild cardiac hypertrophy in Gch1fl/flTie2cre hearts. Endothelial cell BH4 loss was also associated with increased neuronal NOS protein, loss of endothelial NOS protein, and increased phospholamban phosphorylation at serine-17 in cardiomyocytes. Loss of cardiac endothelial cell BH4 led to coronary vascular dysfunction, reduced functional recovery, and increased myocardial infarct size following ischemia-reperfusion injury. Taken together, these studies reveal a specific role for endothelial cell Gch1/BH4 biosynthesis in cardiac function and the response to cardiac ischemia-reperfusion injury. Targeting endothelial cell Gch1 and BH4 biosynthesis may provide a novel therapeutic target for the prevention and treatment of cardiac dysfunction and ischemia-reperfusion injury.NEW & NOTEWORTHY We demonstrate a critical role for endothelial cell Gch1/BH4 biosynthesis in coronary vascular function and cardiac function. Loss of cardiac endothelial cell BH4 leads to coronary vascular dysfunction, reduced functional recovery, and increased myocardial infarct size following ischemia/reperfusion injury. Targeting endothelial cell Gch1 and BH4 biosynthesis may provide a novel therapeutic target for the prevention and treatment of cardiac dysfunction, ischemia injury, and heart failure.
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Affiliation(s)
- Surawee Chuaiphichai
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Sandy M Chu
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Ricardo Carnicer
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Matthew Kelly
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Jenifer K Bendall
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Jillian N Simon
- Center for Translational Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States
| | - Gillian Douglas
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Mark J Crabtree
- Department of Biochemical Sciences, School of Bioscience and Medicine, University of Surrey, Guildford, United Kingdom
| | - Barbara Casadei
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Keith M Channon
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
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5
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Wang D, Liang W, Huo D, Wang H, Wang Y, Cong C, Zhang C, Yan S, Gao M, Su X, Tan X, Zhang W, Han L, Zhang D, Feng H. SPY1 inhibits neuronal ferroptosis in amyotrophic lateral sclerosis by reducing lipid peroxidation through regulation of GCH1 and TFR1. Cell Death Differ 2023; 30:369-382. [PMID: 36443440 PMCID: PMC9950139 DOI: 10.1038/s41418-022-01089-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 10/27/2022] [Accepted: 11/04/2022] [Indexed: 11/29/2022] Open
Abstract
Ferroptosis is an iron-dependent cell death with the accumulation of lipid peroxidation and dysfunction of antioxidant systems. As the critical regulator, glutathione peroxidase 4 (GPX4) has been demonstrated to be down-regulated in amyotrophic lateral sclerosis (ALS). However, the mechanism of ferroptosis in ALS remains unclear. In this research, bioinformatics analysis revealed a high correlation between ALS, ferroptosis, and Speedy/RINGO cell cycle regulator family member A (SPY1). Lipid peroxidation of ferroptosis in hSOD1G93A cells and mice was generated by TFR1-imported excess free iron, decreased GSH, mitochondrial membrane dysfunction, upregulated ALOX15, and inactivation of GCH1, GPX4. SPY1 is a "cyclin-like" protein that has been proved to enhance the viability of hSOD1G93A cells by inhibiting DNA damage. In our study, the decreased expression of SPY1 in ALS was resulted from unprecedented ubiquitination degradation mediated by MDM2 (a nuclear-localized E3 ubiquitin ligase). Further, SPY1 was identified as a novel ferroptosis suppressor via alleviating lipid peroxidation produced by dysregulated GCH1/BH4 axis (a resistance axis of ferroptosis) and transferrin receptor protein 1 (TFR1)-induced iron. Additionally, neuron-specific overexpression of SPY1 significantly delayed the occurrence and prolonged the survival in ALS transgenic mice through the above two pathways. These results suggest that SPY1 is a novel target for both ferroptosis and ALS.
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Affiliation(s)
- Di Wang
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, PR China
| | - Weiwei Liang
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, PR China
- Department of Neurology, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, PR China
| | - Di Huo
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, PR China
| | - Hongyong Wang
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, PR China
| | - Ying Wang
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, PR China
| | - Chaohua Cong
- Department of Neurology, Shanghai JiaoTong University School of Medicine, Shanghai No. 9 People's Hospital, Shanghai, PR China
| | - Chunting Zhang
- Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Science and Medicine, University of Science and Technology of China, Hefei City, Anhui Province, PR China
| | - Shi Yan
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, PR China
| | - Ming Gao
- Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, Heilongjiang Province, PR China
| | - Xiaoli Su
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, PR China
| | - Xingli Tan
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, PR China
| | - Wenmo Zhang
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, PR China
| | - Ling Han
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, PR China
| | - Dongmei Zhang
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, PR China
| | - Honglin Feng
- Department of Neurology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, PR China.
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6
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Cronin SJF, Rao S, Tejada MA, Turnes BL, Licht-Mayer S, Omura T, Brenneis C, Jacobs E, Barrett L, Latremoliere A, Andrews N, Channon KM, Latini A, Arvanites AC, Davidow LS, Costigan M, Rubin LL, Penninger JM, Woolf CJ. Phenotypic drug screen uncovers the metabolic GCH1/BH4 pathway as key regulator of EGFR/KRAS-mediated neuropathic pain and lung cancer. Sci Transl Med 2022; 14:eabj1531. [PMID: 36044597 PMCID: PMC9985140 DOI: 10.1126/scitranslmed.abj1531] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Increased tetrahydrobiopterin (BH4) generated in injured sensory neurons contributes to increased pain sensitivity and its persistence. GTP cyclohydrolase 1 (GCH1) is the rate-limiting enzyme in the de novo BH4 synthetic pathway, and human single-nucleotide polymorphism studies, together with mouse genetic modeling, have demonstrated that decreased GCH1 leads to both reduced BH4 and pain. However, little is known about the regulation of Gch1 expression upon nerve injury and whether this could be modulated as an analgesic therapeutic intervention. We performed a phenotypic screen using about 1000 bioactive compounds, many of which are target-annotated FDA-approved drugs, for their effect on regulating Gch1 expression in rodent injured dorsal root ganglion neurons. From this approach, we uncovered relevant pathways that regulate Gch1 expression in sensory neurons. We report that EGFR/KRAS signaling triggers increased Gch1 expression and contributes to neuropathic pain; conversely, inhibiting EGFR suppressed GCH1 and BH4 and exerted analgesic effects, suggesting a molecular link between EGFR/KRAS and pain perception. We also show that GCH1/BH4 acts downstream of KRAS to drive lung cancer, identifying a potentially druggable pathway. Our screen shows that pharmacologic modulation of GCH1 expression and BH4 could be used to develop pharmacological treatments to alleviate pain and identified a critical role for EGFR-regulated GCH1/BH4 expression in neuropathic pain and cancer in rodents.
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Affiliation(s)
- Shane J. F. Cronin
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
- FM Kirby Neurobiology Center, Boston Children’s Hospital, Boston, MA 02115, USA
- Institute of Molecular Biotechnology Austria (IMBA), Dr. Bohrgasse 3, Vienna A-1030, Austria
| | - Shuan Rao
- Institute of Molecular Biotechnology Austria (IMBA), Dr. Bohrgasse 3, Vienna A-1030, Austria
| | - Miguel A. Tejada
- Institute of Molecular Biotechnology Austria (IMBA), Dr. Bohrgasse 3, Vienna A-1030, Austria
| | - Bruna Lenfers Turnes
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
- FM Kirby Neurobiology Center, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Simon Licht-Mayer
- Institute of Molecular Biotechnology Austria (IMBA), Dr. Bohrgasse 3, Vienna A-1030, Austria
| | - Takao Omura
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
- FM Kirby Neurobiology Center, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Christian Brenneis
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
- FM Kirby Neurobiology Center, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Emily Jacobs
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
- FM Kirby Neurobiology Center, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Lee Barrett
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
- FM Kirby Neurobiology Center, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Alban Latremoliere
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
- FM Kirby Neurobiology Center, Boston Children’s Hospital, Boston, MA 02115, USA
- Departments of Neurosurgery and Neuroscience, Neurosurgery Pain Research Institute, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Nick Andrews
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
- FM Kirby Neurobiology Center, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Keith M. Channon
- Radcliffe Department of Medicine, British Heart Foundation Centre of Research Excellence, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | - Alexandra Latini
- LABOX, Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis, SC 88040-900, Brazil
| | - Anthony C. Arvanites
- Department of Stem Cell and Regenerative Biology, Harvard University, 7 Divinity Ave, Cambridge, MA 02138, USA
- Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA
| | - Lance S. Davidow
- Department of Stem Cell and Regenerative Biology, Harvard University, 7 Divinity Ave, Cambridge, MA 02138, USA
- Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA
| | - Michael Costigan
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
- FM Kirby Neurobiology Center, Boston Children’s Hospital, Boston, MA 02115, USA
| | - Lee L. Rubin
- Department of Stem Cell and Regenerative Biology, Harvard University, 7 Divinity Ave, Cambridge, MA 02138, USA
- Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA
| | - Josef M. Penninger
- Institute of Molecular Biotechnology Austria (IMBA), Dr. Bohrgasse 3, Vienna A-1030, Austria
- Department of Medical Genetics, Life Sciences Institute, UBC, Vancouver, BC V6T 1Z3, Canada
| | - Clifford J. Woolf
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
- FM Kirby Neurobiology Center, Boston Children’s Hospital, Boston, MA 02115, USA
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7
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Liu Z, Dong N, Hui H, Wang Y, Liu F, Xu L, Liu M, Rao Z, Yuan Z, Shang Y, Feng J, Cai Z, Li F. Endothelial cell-derived tetrahydrobiopterin prevents aortic valve calcification. Eur Heart J 2022; 43:1652-1664. [PMID: 35139535 DOI: 10.1093/eurheartj/ehac037] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 01/05/2022] [Accepted: 01/20/2022] [Indexed: 11/14/2022] Open
Abstract
AIMS Tetrahydrobiopterin (BH4) is a critical determinant of the biological function of endothelial nitric oxide synthase. The present study was to investigate the role of valvular endothelial cell (VEC)-derived BH4 in aortic valve calcification. METHODS AND RESULTS Plasma and aortic valve BH4 concentrations and the BH4:BH2 ratio were significantly lower in calcific aortic valve disease patients than in controls. There was a significant decrease of the two key enzymes of BH4 biosynthesis, guanosine 5'-triphosphate cyclohydrolase I (GCH1) and dihydrofolate reductase (DHFR), in calcified aortic valves compared with the normal ones. Endothelial cell-specific deficiency of Gch1 in Apoe-/- (Apoe-/-Gch1fl/flTie2Cre) mice showed a marked increase in transvalvular peak jet velocity, calcium deposition, runt-related transcription factor 2 (Runx2), dihydroethidium (DHE), and 3-nitrotyrosine (3-NT) levels in aortic valve leaflets compared with Apoe-/-Gch1fl/fl mice after a 24-week western diet (WD) challenge. Oxidized LDL (ox-LDL) induced osteoblastic differentiation of valvular interstitial cells (VICs) co-cultured with either si-GCH1- or si-DHFR-transfected VECs, while the effects could be abolished by BH4 supplementation. Deficiency of BH4 in VECs caused peroxynitrite formation increase and 3-NT protein increase under ox-LDL stimulation in VICs. SIN-1, the peroxynitrite generator, significantly up-regulated alkaline phosphatase (ALP) and Runx2 expression in VICs via tyrosine nitration of dynamin-related protein 1 (DRP1) at Y628. Finally, folic acid (FA) significantly attenuated aortic valve calcification in WD-fed Apoe-/- mice through increasing DHFR and salvaging BH4 biosynthesis. CONCLUSION The reduction in endothelial-dependent BH4 levels promoted peroxynitrite formation, which subsequently resulted in DRP1 tyrosine nitration and osteoblastic differentiation of VICs, thereby leading to aortic valve calcification. Supplementation of FA in diet attenuated hypercholesterolaemia-induced aortic valve calcification by salvaging BH4 bioavailability.
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Affiliation(s)
- Zongtao Liu
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Ave, Wuhan 430022, Hubei, China
| | - Nianguo Dong
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Ave, Wuhan 430022, Hubei, China
| | - Haipeng Hui
- Department of Cardiology, the Second Medical Center & National Clinical Research Center for Geriatric Diseases, Chinese PLA General Hospital, 28# Fuxing Road, Beijing 100853, China
| | - Yixuan Wang
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Ave, Wuhan 430022, Hubei, China
| | - Fayun Liu
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Ave, Wuhan 430022, Hubei, China
| | - Li Xu
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Ave, Wuhan 430022, Hubei, China
| | - Ming Liu
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Ave, Wuhan 430022, Hubei, China
| | - Zhenqi Rao
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Ave, Wuhan 430022, Hubei, China
| | - Zhen Yuan
- Department of Cardiology, the Second Affiliated Hospital, Zhejiang University School of Medicine, 88 Jiefang Road, Hangzhou 310009, Zhejiang, China
| | - Yuqiang Shang
- Department of Cardiovascular Surgery, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, Hubei, China
| | - Jun Feng
- Department of Emergency and Intensive Care Unit, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Ave, Wuhan 430030, Hubei, China
| | - Zhejun Cai
- Department of Cardiology, the Second Affiliated Hospital, Zhejiang University School of Medicine, 88 Jiefang Road, Hangzhou 310009, Zhejiang, China
| | - Fei Li
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Ave, Wuhan 430022, Hubei, China
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Chuaiphichai S, Yu GZ, Tan CM, Whiteman C, Douglas G, Dickinson Y, Drydale EN, Appari M, Zhang W, Crabtree MJ, McNeill E, Hale AB, Lewandowski AJ, Alp NJ, Vatish M, Leeson P, Channon KM. Endothelial GTPCH (GTP Cyclohydrolase 1) and Tetrahydrobiopterin Regulate Gestational Blood Pressure, Uteroplacental Remodeling, and Fetal Growth. Hypertension 2021; 78:1871-1884. [PMID: 34689592 PMCID: PMC8577301 DOI: 10.1161/hypertensionaha.120.17646] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 07/07/2021] [Indexed: 01/01/2023]
Abstract
[Figure: see text].
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Affiliation(s)
- Surawee Chuaiphichai
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, United Kingdom (S.C., C.W., G.D., Y.D., E.N.D., M.A., M.J.C., E.M., A.B.H., N.J.A., K.M.C.)
| | - Grace Z. Yu
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine (G.Z.Y., C.M.J.T., A.J.L., P.L.), University of Oxford, United Kingdom
| | - Cheryl M.J. Tan
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine (G.Z.Y., C.M.J.T., A.J.L., P.L.), University of Oxford, United Kingdom
| | - Christopher Whiteman
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, United Kingdom (S.C., C.W., G.D., Y.D., E.N.D., M.A., M.J.C., E.M., A.B.H., N.J.A., K.M.C.)
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine (G.Z.Y., C.M.J.T., A.J.L., P.L.), University of Oxford, United Kingdom
- Nuffield Department of Women’s and Reproductive Health (W.Z., M.V.), University of Oxford, United Kingdom
- National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, Oxford University Hospitals National Health Service Foundation Trust, John Radcliffe Hospital, United Kingdom (M.V., K.M.C.)
| | - Gillian Douglas
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, United Kingdom (S.C., C.W., G.D., Y.D., E.N.D., M.A., M.J.C., E.M., A.B.H., N.J.A., K.M.C.)
| | - Yasmin Dickinson
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, United Kingdom (S.C., C.W., G.D., Y.D., E.N.D., M.A., M.J.C., E.M., A.B.H., N.J.A., K.M.C.)
| | - Edward N. Drydale
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, United Kingdom (S.C., C.W., G.D., Y.D., E.N.D., M.A., M.J.C., E.M., A.B.H., N.J.A., K.M.C.)
| | - Mahesh Appari
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, United Kingdom (S.C., C.W., G.D., Y.D., E.N.D., M.A., M.J.C., E.M., A.B.H., N.J.A., K.M.C.)
| | - Wei Zhang
- Nuffield Department of Women’s and Reproductive Health (W.Z., M.V.), University of Oxford, United Kingdom
| | - Mark J. Crabtree
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, United Kingdom (S.C., C.W., G.D., Y.D., E.N.D., M.A., M.J.C., E.M., A.B.H., N.J.A., K.M.C.)
| | - Eileen McNeill
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, United Kingdom (S.C., C.W., G.D., Y.D., E.N.D., M.A., M.J.C., E.M., A.B.H., N.J.A., K.M.C.)
| | - Ashley B. Hale
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, United Kingdom (S.C., C.W., G.D., Y.D., E.N.D., M.A., M.J.C., E.M., A.B.H., N.J.A., K.M.C.)
| | - Adam J. Lewandowski
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine (G.Z.Y., C.M.J.T., A.J.L., P.L.), University of Oxford, United Kingdom
| | - Nicholas J. Alp
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, United Kingdom (S.C., C.W., G.D., Y.D., E.N.D., M.A., M.J.C., E.M., A.B.H., N.J.A., K.M.C.)
| | - Manu Vatish
- Nuffield Department of Women’s and Reproductive Health (W.Z., M.V.), University of Oxford, United Kingdom
- National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, Oxford University Hospitals National Health Service Foundation Trust, John Radcliffe Hospital, United Kingdom (M.V., K.M.C.)
| | - Paul Leeson
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine (G.Z.Y., C.M.J.T., A.J.L., P.L.), University of Oxford, United Kingdom
| | - Keith M. Channon
- Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence, Radcliffe Department of Medicine, University of Oxford, United Kingdom (S.C., C.W., G.D., Y.D., E.N.D., M.A., M.J.C., E.M., A.B.H., N.J.A., K.M.C.)
- National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, Oxford University Hospitals National Health Service Foundation Trust, John Radcliffe Hospital, United Kingdom (M.V., K.M.C.)
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Zhong GC, Zhao ZB, Cheng Y, Wang YB, Qiu C, Mao LH, Hu JJ, Cai D, Liu Y, Gong JP, Li SW. Epigenetic silencing of GCH1promotes hepatocellular carcinoma growth by activating superoxide anion-mediated ASK1/p38 signaling via inhibiting tetrahydrobiopterin de novo biosynthesis. Free Radic Biol Med 2021; 168:81-94. [PMID: 33781891 DOI: 10.1016/j.freeradbiomed.2021.03.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 03/19/2021] [Accepted: 03/20/2021] [Indexed: 12/21/2022]
Abstract
Metabolic reprogramming is a hallmark of cancer, including hepatocellular carcinoma (HCC). However, its role in HCC remains to be elucidated. Herein, we identified GTP cyclohydrolase 1 (GCH1), the first rate-limiting enzyme in tetrahydrobiopterin (BH4) de novo biosynthesis, as a novel metabolic regulator of HCC. GCH1 was frequently down-regulated in HCC tissues and cell lines by promoter methylation. Low GCH1 expression was associated with larger tumor size, increased tumor number, and worse prognosis in two independent cohorts of HCC patients. Functionally, GCH1 silencing promoted HCC growth in vitro and in vivo, while GCH1 overexpression exerted an opposite effect. The metabolite BH4 inhibited HCC growth in vitro and in vivo. GCH1 silencing exerted its growth-promoting effect through directly inhibiting BH4 de novo biosynthesis. Mechanistically, GCH1 silencing activated ASK1/p38 signaling; pharmacological or genetic inhibition of ASK1 or p38 abolished GCH1 silencing-induced growth-promoting effect. Further mechanistic studies found that GCH1 silencing-induced BH4 reduction resulted in an increase of intracellular superoxide anion levels in a dose-dependent manner, which mediated the activation of ASK1/p38 signaling. Collectively, our study reveals that epigenetic silencing of GCH1 promotes HCC growth by activating superoxide anion-mediated ASK1/p38 signaling via inhibiting BH4 de novo biosynthesis, suggesting that targeting GCH1/BH4 pathway may be a promising therapeutic strategy to combat HCC.
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Affiliation(s)
- Guo-Chao Zhong
- Department of Hepatobiliary Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zhi-Bo Zhao
- Department of Hepatobiliary Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yao Cheng
- Department of Hepatobiliary Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yun-Bing Wang
- Department of Hepatobiliary Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Chan Qiu
- Department of Gastroenterology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Lin-Hong Mao
- Department of Gastroenterology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Jie-Jun Hu
- Department of Hepatobiliary Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Dong Cai
- Department of Hepatobiliary Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yan Liu
- Department of Gastroenterology, The Fifth People's Hospital of Chengdu, Chengdu, China
| | - Jian-Ping Gong
- Department of Hepatobiliary Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China.
| | - Sheng-Wei Li
- Department of Hepatobiliary Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China.
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10
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Wang Z, Cheng C, Yang X, Zhang C. L-phenylalanine attenuates high salt-induced hypertension in Dahl SS rats through activation of GCH1-BH4. PLoS One 2021; 16:e0250126. [PMID: 33857222 PMCID: PMC8049246 DOI: 10.1371/journal.pone.0250126] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 03/31/2021] [Indexed: 02/07/2023] Open
Abstract
Amino acid metabolism plays an important role in controlling blood pressure by regulating the production of NO and ROS. The present study examined amino acid levels in the serum of Dahl SS rats and SS.13BN rats fed a low or high salt diet. We observed that 8 of 27 amino acids responded to a high salt diet in SS rats. Thus, we hypothesized that a defect in amino acids may contribute to the development of salt-induced hypertension. L-phenylalanine was used to treat SS rats with a low or high salt diet. The results demonstrated that L-phenylalanine supplementation significantly enhanced the serum nitrite levels and attenuated the high salt-induced hypertension in SS rats. Low levels of BH4 and nitrite and the impaired vascular response to acetylcholine were rescued by L-phenylalanine supplementation. Moreover, increased GTP cyclohydrolase (GCH1) mRNA, levels of BH4 and nitrite, and reduced superoxide production were observed in the kidneys of hypertensive SS rats with L-phenylalanine. The antihypertensive effects of L-phenylalanine might be mediated by enhancing BH4 biosynthesis and decreasing superoxide production from NO synthase, thereby protecting vascular and kidney function with reduced ROS and elevated NO levels. The present study demonstrated that L-phenylalanine supplementation restored vascular function, suggesting L-phenylalanine represented a potential target to attenuate high salt-sensitive hypertension through GCH1-BH4.
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Affiliation(s)
- Zhengjun Wang
- School of Psychology, Shaanxi Normal University and Key Laboratory for Behavior and Cognitive Neuroscience of Shaanxi Province, Xi’an, China
- * E-mail: (ZW); (CZ)
| | - Chen Cheng
- School of Psychology, Shaanxi Normal University and Key Laboratory for Behavior and Cognitive Neuroscience of Shaanxi Province, Xi’an, China
| | - Xiaoyu Yang
- School of Life Science, Shaanxi Normal University, Xi’an, China
| | - Chen Zhang
- College of Animal Sciences, Zhejiang University, Hangzhou, China
- School of Life Sciences, Northwestern Polytechnical University, Xi’an, China
- * E-mail: (ZW); (CZ)
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11
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Carnicer R, Duglan D, Ziberna K, Recalde A, Reilly S, Simon JN, Mafrici S, Arya R, Rosello-Lleti E, Chuaiphichai S, Tyler D, Lygate CA, Channon KM, Casadei B. BH4 Increases nNOS Activity and Preserves Left Ventricular Function in Diabetes. Circ Res 2021; 128:585-601. [PMID: 33494625 PMCID: PMC7612785 DOI: 10.1161/circresaha.120.316656] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 01/25/2021] [Indexed: 12/20/2022]
Abstract
RATIONALE In diabetic patients, heart failure with predominant left ventricular (LV) diastolic dysfunction is a common complication for which there is no effective treatment. Oxidation of the NOS (nitric oxide synthase) cofactor tetrahydrobiopterin (BH4) and dysfunctional NOS activity have been implicated in the pathogenesis of the diabetic vascular and cardiomyopathic phenotype. OBJECTIVE Using mice models and human myocardial samples, we evaluated whether and by which mechanism increasing myocardial BH4 availability prevented or reversed LV dysfunction induced by diabetes. METHODS AND RESULTS In contrast to the vascular endothelium, BH4 levels, superoxide production, and NOS activity (by liquid chromatography) did not differ in the LV myocardium of diabetic mice or in atrial tissue from diabetic patients. Nevertheless, the impairment in both cardiomyocyte relaxation and [Ca2+]i (intracellular calcium) decay and in vivo LV function (echocardiography and tissue Doppler) that developed in wild-type mice 12 weeks post-diabetes induction (streptozotocin, 42-45 mg/kg) was prevented in mGCH1-Tg (mice with elevated myocardial BH4 content secondary to trangenic overexpression of GTP-cyclohydrolase 1) and reversed in wild-type mice receiving oral BH4 supplementation from the 12th to the 18th week after diabetes induction. The protective effect of BH4 was abolished by CRISPR/Cas9-mediated knockout of nNOS (the neuronal NOS isoform) in mGCH1-Tg. In HEK (human embryonic kidney) cells, S-nitrosoglutathione led to a PKG (protein kinase G)-dependent increase in plasmalemmal density of the insulin-independent glucose transporter GLUT-1 (glucose transporter-1). In cardiomyocytes, mGCH1 overexpression induced a NO/sGC (soluble guanylate cyclase)/PKG-dependent increase in glucose uptake via GLUT-1, which was instrumental in preserving mitochondrial creatine kinase activity, oxygen consumption rate, LV energetics (by 31phosphorous magnetic resonance spectroscopy), and myocardial function. CONCLUSIONS We uncovered a novel mechanism whereby myocardial BH4 prevents and reverses LV diastolic and systolic dysfunction associated with diabetes via an nNOS-mediated increase in insulin-independent myocardial glucose uptake and utilization. These findings highlight the potential of GCH1/BH4-based therapeutics in human diabetic cardiomyopathy. Graphic Abstract: A graphic abstract is available for this article.
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Affiliation(s)
| | - Drew Duglan
- Cardiovascular Medicine, University of Oxford
| | | | | | | | | | | | - Ritu Arya
- Cardiovascular Medicine, University of Oxford
| | | | | | - Damian Tyler
- Physiology, Anatomy and Genetics, University of Oxford
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12
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Ebenhoch R, Prinz S, Kaltwasser S, Mills DJ, Meinecke R, Rübbelke M, Reinert D, Bauer M, Weixler L, Zeeb M, Vonck J, Nar H. A hybrid approach reveals the allosteric regulation of GTP cyclohydrolase I. Proc Natl Acad Sci U S A 2020; 117:31838-31849. [PMID: 33229582 PMCID: PMC7750480 DOI: 10.1073/pnas.2013473117] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Guanosine triphosphate (GTP) cyclohydrolase I (GCH1) catalyzes the conversion of GTP to dihydroneopterin triphosphate (H2NTP), the initiating step in the biosynthesis of tetrahydrobiopterin (BH4). Besides other roles, BH4 functions as cofactor in neurotransmitter biosynthesis. The BH4 biosynthetic pathway and GCH1 have been identified as promising targets to treat pain disorders in patients. The function of mammalian GCH1s is regulated by a metabolic sensing mechanism involving a regulator protein, GCH1 feedback regulatory protein (GFRP). GFRP binds to GCH1 to form inhibited or activated complexes dependent on availability of cofactor ligands, BH4 and phenylalanine, respectively. We determined high-resolution structures of human GCH1-GFRP complexes by cryoelectron microscopy (cryo-EM). Cryo-EM revealed structural flexibility of specific and relevant surface lining loops, which previously was not detected by X-ray crystallography due to crystal packing effects. Further, we studied allosteric regulation of isolated GCH1 by X-ray crystallography. Using the combined structural information, we are able to obtain a comprehensive picture of the mechanism of allosteric regulation. Local rearrangements in the allosteric pocket upon BH4 binding result in drastic changes in the quaternary structure of the enzyme, leading to a more compact, tense form of the inhibited protein, and translocate to the active site, leading to an open, more flexible structure of its surroundings. Inhibition of the enzymatic activity is not a result of hindrance of substrate binding, but rather a consequence of accelerated substrate binding kinetics as shown by saturation transfer difference NMR (STD-NMR) and site-directed mutagenesis. We propose a dissociation rate controlled mechanism of allosteric, noncompetitive inhibition.
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Affiliation(s)
- Rebecca Ebenhoch
- Medicinal Chemistry, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397 Biberach an der Riss, Germany
| | - Simone Prinz
- Structural Biology, Max Planck Institute of Biophysics, 60438 Frankfurt am Main, Germany
| | - Susann Kaltwasser
- Structural Biology, Max Planck Institute of Biophysics, 60438 Frankfurt am Main, Germany
| | - Deryck J Mills
- Structural Biology, Max Planck Institute of Biophysics, 60438 Frankfurt am Main, Germany
| | - Robert Meinecke
- Medicinal Chemistry, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397 Biberach an der Riss, Germany
| | - Martin Rübbelke
- Medicinal Chemistry, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397 Biberach an der Riss, Germany
| | - Dirk Reinert
- Medicinal Chemistry, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397 Biberach an der Riss, Germany
| | - Margit Bauer
- Medicinal Chemistry, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397 Biberach an der Riss, Germany
| | - Lisa Weixler
- Medicinal Chemistry, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397 Biberach an der Riss, Germany
| | - Markus Zeeb
- Medicinal Chemistry, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397 Biberach an der Riss, Germany
| | - Janet Vonck
- Structural Biology, Max Planck Institute of Biophysics, 60438 Frankfurt am Main, Germany
| | - Herbert Nar
- Medicinal Chemistry, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397 Biberach an der Riss, Germany;
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Liu L, Zhang H, Shi Y, Pan L. Prostaglandin E1 Improves Cerebral Microcirculation Through Activation of Endothelial NOS and GRPCH1. J Mol Neurosci 2020; 70:2041-2048. [PMID: 32483670 DOI: 10.1007/s12031-020-01610-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 05/21/2020] [Indexed: 12/26/2022]
Abstract
Endothelial dysfunction greatly contributes to microcirculation disorder. The role of prostaglandin E1 (PGE1) in cerebral microcirculation was explored in vitro. LPS (0.5 or 1 μg/ml) was added to induce injury in human brain microvascular endothelial cells (HCMEC/D3). CCK-8 was applied to check viabilities of HCMEC/D3 before and after LPS treatment. Western blot witnessed the changes in protein expressions of inflammatory cytokines, IL-6 and TNF-α. Caspase-3/7 activity was analyzed and so were the protein expressions of pro-apoptotic gene BAX and anti-apoptotic gene Bcl-2. mRNA expressions of eNOS and GTPCH1 were evaluated by RT-qPCR. After overexpressing eNOS or GTPCH1 in LPS-induced HCMEC/D3 cells, viabilities, inflammatory cytokines, caspase-3/7 activity, and apoptosis-related genes were detected. The modulation of PGE1 in eNOS and GTPCH1 production, viability, inflammation, and apoptosis was investigated. The inhibitor of eNOS or GTPCH1 was introduced to examine impacts of eNOS or GTPCH1 could have on the PGE1 function. LPS decreased cell viabilities, eNOS and GTPCH1 expression, and promoted inflammation and apoptosis in HCMEC/D3 cells. Overexpressed eNOS or GTPCH1 promoted cell viabilities and suppressed inflammation and apoptosis. PGE1 enhanced viability and decreased inflammation and apoptosis in cells treated by LPS. PGE1 activated eNOS and GTPCH1 and inhibition of eNOS or GTPCH1 led to the attenuation of the protective functions of PGE1 in LPS-induced cells. PGE1 protected HCMEC/D3 cells from injuries induced by LPS by activation of eNOS and GTPCH1, suggesting that PGE1 might be used to help maintain cerebral microcirculation in future.
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Affiliation(s)
- Lei Liu
- Department of Cardiology, Jinshan Hospital of Fudan University, No.1508, Longhang Road, Shanghai, 201508, China
| | - Hexi Zhang
- Department of Cardiology, Jinshan Hospital of Fudan University, No.1508, Longhang Road, Shanghai, 201508, China
| | - Yijun Shi
- Department of Cardiology, Jinshan Hospital of Fudan University, No.1508, Longhang Road, Shanghai, 201508, China
| | - Lijian Pan
- Department of Cardiology, Jinshan Hospital of Fudan University, No.1508, Longhang Road, Shanghai, 201508, China.
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Luo H, Yang L, Kim SH, Wulff T, Feist AM, Herrgard M, Palsson BØ. Directed Metabolic Pathway Evolution Enables Functional Pterin-Dependent Aromatic-Amino-Acid Hydroxylation in Escherichia coli. ACS Synth Biol 2020; 9:494-499. [PMID: 32149495 DOI: 10.1021/acssynbio.9b00488] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Tetrahydrobiopterin-dependent hydroxylation of aromatic amino acids is the first step in the biosynthesis of many neuroactive compounds in humans. A fundamental challenge in building these pathways in Escherichia coli is the provision of the non-native hydroxylase cofactor, tetrahydrobiopterin. To solve this, we designed a genetic selection that relies on the tyrosine synthesis activity of phenylalanine hydroxylase. Using adaptive laboratory evolution, we demonstrate the use of this selection to discover: (1) a minimum set of heterologous enzymes and a host folE (T198I) mutation for achieving this type of hydroxylation chemistry in whole cells, (2) functional complementation of tetrahydrobiopterin by indigenous cofactors, and (3) a tryptophan hydroxylase mutation for improving protein abundance. Thus, the goal of having functional aromatic-amino-acid hydroxylation in E. coli was achieved through directed metabolic pathway evolution.
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Affiliation(s)
- Hao Luo
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby 2800, Denmark
| | - Lei Yang
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby 2800, Denmark
| | - Se Hyeuk Kim
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby 2800, Denmark
| | - Tune Wulff
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby 2800, Denmark
| | - Adam M Feist
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby 2800, Denmark
- Department of Bioengineering, University of California, San Diego, La Jolla, California 92093, United States of America
| | - Markus Herrgard
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby 2800, Denmark
| | - Bernhard Ø Palsson
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby 2800, Denmark
- Department of Bioengineering, University of California, San Diego, La Jolla, California 92093, United States of America
- Department of Pediatrics, University of California, San Diego, La Jolla, California 92093, United States of America
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15
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Le Y, Wei R, Yang K, Lang S, Gu L, Liu J, Hong T, Yang J. Liraglutide ameliorates palmitate-induced oxidative injury in islet microvascular endothelial cells through GLP-1 receptor/PKA and GTPCH1/eNOS signaling pathways. Peptides 2020; 124:170212. [PMID: 31770577 DOI: 10.1016/j.peptides.2019.170212] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 11/21/2019] [Accepted: 11/22/2019] [Indexed: 12/27/2022]
Abstract
In type 2 diabetes, lipotoxicity damages islet microvascular endothelial cells (IMECs), leading to pancreatic islet β cell dysfunction directly or indirectly. Glucagon-like peptide-1 (GLP-1) and its analogs have beneficial roles in endothelial cells. However, the protective effects of GLP-1 agents on IMECs and their potential mechanism remained obscure. In this study, exposure of MS-1 (a cell line derived from mouse IMECs) to different concentrations of palmitic acid (PA) was used to establish an injury model. The cells exposed to PA (0.25 mmol/L) were treated with a GLP-1 analog liraglutide (3, 10, 30, and 100 nmol/L). Reactive oxygen species (ROS) generation, apoptosis-related protein level, and endothelin-1 production were detected. The protein levels of signaling molecules were analyzed and specific inhibitors or blockers were used to identify involvement of signaling pathways in the effects of liraglutide. Results showed that PA significantly increased ROS generation and the levels of pro-apoptotic protein Bax, and decreased the levels of anti-apoptotic protein Bcl-2 and the mRNA expression and secretion of endothelin-1. Meanwhile, PA downregulated the protein levels of GLP-1 receptor (GLP-1R), phosphorylated protein kinase A (PKA), guanosine 5'-triphosphate cyclohydrolase 1 (GTPCH1), and endothelial nitric oxide synthase (eNOS). Furthermore, liraglutide ameliorated all these effects of PA in a dose-dependent manner. Importantly, GLP-1R antagonist exendin (9-39), PKA inhibitor H89, GTPCH1 inhibitor 2,4-diamino-6-hydroxypyrimidine, or NOS inhibitor N-nitro-l-arginine-methyl ester abolished the liraglutide-mediated amelioration in PA-impaired MS-1 cells. In conclusion, liraglutide ameliorates the PA-induced oxidative stress, apoptosis, and endothelin-1 secretion dysfunction in mouse IMECs through GLP-1R/PKA and GTPCH1/eNOS signaling pathways.
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Affiliation(s)
- Yunyi Le
- Department of Endocrinology and Metabolism, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Rui Wei
- Department of Endocrinology and Metabolism, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Kun Yang
- Department of Endocrinology and Metabolism, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Shan Lang
- Department of Endocrinology and Metabolism, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Liangbiao Gu
- Department of Endocrinology and Metabolism, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Junling Liu
- Department of Endocrinology and Metabolism, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China
| | - Tianpei Hong
- Department of Endocrinology and Metabolism, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China.
| | - Jin Yang
- Department of Endocrinology and Metabolism, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, China.
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16
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Liu P, Liu J, Wu Y, Xi W, Wei Y, Yuan Z, Zhuo X. Zinc supplementation protects against diabetic endothelial dysfunction via GTP cyclohydrolase 1 restoration. Biochem Biophys Res Commun 2020; 521:1049-1054. [PMID: 31732151 DOI: 10.1016/j.bbrc.2019.11.046] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 11/06/2019] [Indexed: 12/15/2022]
Abstract
This study explored whether zinc supplementation alleviates diabetic endothelial dysfunction and the possible mechanisms underlying. We found that high glucose exposure significantly increased reactive oxygen species (ROS) and decreased guanosine 5'-triphosphate cyclohydrolase 1 (GTPCH1) and tetrahydrobiopterin (BH4) levels in bovine aortic endothelial cells (BAECs) in a time-dependent manner. High glucose increased zinc release from GTPCH1 in a similar trend. Zinc supplementation restored GTPCH1 and BH4 levels and blocked ROS accumulation in both BACEs and wild type GTPCH1 transfected HEK293 cells, but not in the zinc-free C141R mutant of GTPCH1 transfected ones. In vivo experiments showed that exogenous supplementation of zinc to streptozotocin (STZ)-induced diabetic mice partially improved the impaired maximal endothelium-dependent vasorelaxation, reversed the aberrant reduction of GTPCH1 and BH4, and suppressed the elevation of ROS in the aortas. In conclusion, our study demonstrated a novel mechanism that via GTPCH1 restoration zinc supplementation exerts a protective benefit on diabetic endothelial dysfunction.
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Affiliation(s)
- Peining Liu
- Department of Cardiovascular Medicine, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Junhui Liu
- Department of Clinical Laboratory, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Yue Wu
- Department of Cardiovascular Medicine, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, China; Key Laboratory of Molecular Cardiology, Shaanxi Province, Xi'an, Shaanxi, China
| | - Wen Xi
- Department of Clinical Laboratory, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Yuanyuan Wei
- Department of Cardiovascular Medicine, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Zuyi Yuan
- Department of Cardiovascular Medicine, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, China; Key Laboratory of Molecular Cardiology, Shaanxi Province, Xi'an, Shaanxi, China; Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education, Xi'an, Shaanxi, China.
| | - Xiaozhen Zhuo
- Department of Cardiovascular Medicine, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, China; Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education, Xi'an, Shaanxi, China.
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17
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Wang C, Chao Y, Xu W, Liang M, Deng S, Zhang D, Huang K. CTRP13 Preserves Endothelial Function by Targeting GTP Cyclohydrolase 1 in Diabetes. Diabetes 2020; 69:99-111. [PMID: 31676569 DOI: 10.2337/db19-0635] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 10/21/2019] [Indexed: 11/13/2022]
Abstract
Endothelial dysfunction plays a crucial role in the progress of diabetic vasculopathy. C1q/tumor necrosis factor-related protein 13 (CTRP13) is a secreted adipokine that can ameliorate atherosclerosis and vascular calcification. However, the role of CTRP13 in regulating endothelial function in diabetes has yet to be explored. In this study, CTRP13 treatment improved endothelium-dependent relaxation in the aortae and mesenteric arteries of both db/db mice and streptozotocin-injected mice. CTRP13 supplement also rescued the impaired endothelium-dependent relaxation ex vivo in the db/db mouse aortae and in high glucose (HG)-treated mouse aortae. Additionally, CTRP13 treatment reduced reactive oxygen species overproduction and improved nitric oxide (NO) production and endothelial NO synthase (eNOS) coupling in the aortae of diabetic mice and in HG-treated human umbilical vein endothelial cells. Mechanistically, CTRP13 could increase GTP cyclohydrolase 1 (GCH1) expression and tetrahydrobiopterin (BH4) levels to ameliorate eNOS coupling. More importantly, CTRP13 rescued HG-induced inhibition of protein kinase A (PKA) activity. Increased PKA activity enhanced phosphorylation of the peroxisome proliferator-activated receptor α and its recruitment to the GCH1 promoter, thus activating GCH1 transcription and, ultimately, endothelial relaxation. Together, these results suggest that CTRP13 preserves endothelial function in diabetic mice by regulating GCH1/BH4 axis-dependent eNOS coupling, suggesting the therapeutic potential of CTRP13 against diabetic vasculopathy.
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Affiliation(s)
- Cheng Wang
- Clinic Center of Human Gene Research, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Department of Rheumatology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yuelin Chao
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Wenjing Xu
- Clinic Center of Human Gene Research, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Minglu Liang
- Clinic Center of Human Gene Research, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shan Deng
- Clinic Center of Human Gene Research, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Donghong Zhang
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA
| | - Kai Huang
- Clinic Center of Human Gene Research, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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18
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Bailey JD, Diotallevi M, Nicol T, McNeill E, Shaw A, Chuaiphichai S, Hale A, Starr A, Nandi M, Stylianou E, McShane H, Davis S, Fischer R, Kessler BM, McCullagh J, Channon KM, Crabtree MJ. Nitric Oxide Modulates Metabolic Remodeling in Inflammatory Macrophages through TCA Cycle Regulation and Itaconate Accumulation. Cell Rep 2019; 28:218-230.e7. [PMID: 31269442 PMCID: PMC6616861 DOI: 10.1016/j.celrep.2019.06.018] [Citation(s) in RCA: 137] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 02/25/2019] [Accepted: 06/05/2019] [Indexed: 01/04/2023] Open
Abstract
Classical activation of macrophages (M(LPS+IFNγ)) elicits the expression of inducible nitric oxide synthase (iNOS), generating large amounts of NO and inhibiting mitochondrial respiration. Upregulation of glycolysis and a disrupted tricarboxylic acid (TCA) cycle underpin this switch to a pro-inflammatory phenotype. We show that the NOS cofactor tetrahydrobiopterin (BH4) modulates IL-1β production and key aspects of metabolic remodeling in activated murine macrophages via NO production. Using two complementary genetic models, we reveal that NO modulates levels of the essential TCA cycle metabolites citrate and succinate, as well as the inflammatory mediator itaconate. Furthermore, NO regulates macrophage respiratory function via changes in the abundance of critical N-module subunits in Complex I. However, NO-deficient cells can still upregulate glycolysis despite changes in the abundance of glycolytic intermediates and proteins involved in glucose metabolism. Our findings reveal a fundamental role for iNOS-derived NO in regulating metabolic remodeling and cytokine production in the pro-inflammatory macrophage.
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Affiliation(s)
- Jade D Bailey
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | - Marina Diotallevi
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | - Thomas Nicol
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | - Eileen McNeill
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | - Andrew Shaw
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | - Surawee Chuaiphichai
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | - Ashley Hale
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | - Anna Starr
- School of Cancer and Pharmaceutical Science, Faculty of Life Sciences and Medicine, King's College London, London SE1 9NH, UK
| | - Manasi Nandi
- School of Cancer and Pharmaceutical Science, Faculty of Life Sciences and Medicine, King's College London, London SE1 9NH, UK
| | | | - Helen McShane
- Jenner Institute, University of Oxford, Oxford OX3 7DQ, UK
| | - Simon Davis
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, UK
| | - Roman Fischer
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, UK
| | - Benedikt M Kessler
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, UK
| | - James McCullagh
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK
| | - Keith M Channon
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK.
| | - Mark J Crabtree
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK.
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19
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Sharma NM, Liu X, Llewellyn TL, Katsurada K, Patel KP. Exercise training augments neuronal nitric oxide synthase dimerization in the paraventricular nucleus of rats with chronic heart failure. Nitric Oxide 2019; 87:73-82. [PMID: 30878404 PMCID: PMC6527363 DOI: 10.1016/j.niox.2019.03.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 02/06/2019] [Accepted: 03/08/2019] [Indexed: 12/20/2022]
Abstract
Exercise training (ExT) is an established non-pharmacological therapy that improves the health and quality of life in patients with chronic heart failure (CHF). Exaggerated sympathetic drive characterizes CHF due to an imbalance of the autonomic nervous system. Neuronal nitric oxide synthase (nNOS) in the paraventricular nucleus (PVN) produce nitric oxide (NO•), which is known to regulate the sympathetic tone. Previously we have shown that during CHF, the catalytically active dimeric form of nNOS is significantly decreased with a concurrent increase in protein inhibitor of nNOS (PIN) expression, a protein that dissociates dimeric nNOS to monomers and facilitates its degradation. Dimerization of nNOS also requires (6R)-5,6,7,8-tetrahydrobiopterin (BH4) for stability and activity. Previously, we have shown that ExT improves NO-mediated sympathetic inhibition in the PVN; however, the molecular mechanism remains elusive. We hypothesized; ExT restores the sympathetic drive by increasing the levels and catalytically active form of nNOS by abrogating changes in the PIN in the PVN of CHF rats. CHF was induced in adult male Sprague-Dawley rats by coronary artery ligation, which reliably mimics CHF in patients with myocardial infarction. After 4 weeks of surgery, Sham and CHF rats were subjected to 3 weeks of progressive treadmill exercise. ExT significantly (p < 0.05) decreased PIN expression and increased dimer/monomer ratio of nNOS in the PVN of rats with CHF. Moreover, we found decreased GTP cyclohydrolase 1(GCH1) expression: a rate-limiting enzyme for BH4 biosynthesis in the PVN of CHF rats suggesting that perhaps reduced BH4 availability may also contribute to decreased nNOS dimers. Interestingly, CHF induced decrease in GCH1 expression was increased with ExT. Our findings revealed that ExT rectified decreased PIN and GCH1 expression and increased dimer/monomer ratio of nNOS in the PVN, which may lead to increase NO• bioavailability resulting in amelioration of activated sympathetic drive during CHF.
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Affiliation(s)
- Neeru M Sharma
- Department of Cellular and Integrative Physiology, UNMC, Omaha, NE 68198-5850, USA.
| | - Xuefei Liu
- Department of Cellular and Integrative Physiology, UNMC, Omaha, NE 68198-5850, USA
| | - Tamra L Llewellyn
- Department of Cellular and Integrative Physiology, UNMC, Omaha, NE 68198-5850, USA
| | - Kenichi Katsurada
- Department of Cellular and Integrative Physiology, UNMC, Omaha, NE 68198-5850, USA
| | - Kaushik P Patel
- Department of Cellular and Integrative Physiology, UNMC, Omaha, NE 68198-5850, USA
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20
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Liang Q, Wang K, Liu X, Riaz B, Jiang L, Wan X, Ye X, Zhang C. Improved folate accumulation in genetically modified maize and wheat. J Exp Bot 2019; 70:1539-1551. [PMID: 30753561 PMCID: PMC6411382 DOI: 10.1093/jxb/ery453] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 12/13/2018] [Indexed: 05/10/2023]
Abstract
Folates are indispensable co-factors for one-carbon metabolism in all organisms. In humans, suboptimal folate intake results in serious disorders. One promising strategy for improving human folate status is to enhance folate levels in food crops by metabolic engineering. In this study, we cloned two GmGCHI (GTP cyclohydrolase I) genes (Gm8gGCHI and Gm3gGCHI) and one GmADCS (aminodeoxychorismate synthase) gene from soybean, which are responsible for synthesizing the folate precursors pterin and p-aminobenzoate, respectively. We initially confirmed their functions in transgenic Arabidopsis plants and found that Gm8gGCHI increased pterin and folate production more than Gm3gGCHI did. We then co-expressed Gm8gGCHI and GmADCS driven by endosperm-specific promoters in maize and wheat, two major staple crops, to boost their folate metabolic flux. A 4.2-fold and 2.3-fold increase in folate levels were observed in transgenic maize and wheat grains, respectively. To optimize wheat folate enhancement, codon-optimized Gm8gGCHI and tomato LeADCS genes under the control of a wheat endosperm-specific glutenin promoter (1Dx5) were co-transformed. This yielded a 5.6-fold increase in folate in transgenic wheat grains (Gm8gGCHI+/LeADCS+). This two-gene co-expression strategy therefore has the potential to greatly enhance folate levels in maize and wheat, thus improving their nutritional value.
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Affiliation(s)
- Qiuju Liang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Ke Wang
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiaoning Liu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Bisma Riaz
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Ling Jiang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xing Wan
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xingguo Ye
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Chunyi Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
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21
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Zschiebsch K, Fischer C, Wilken‐Schmitz A, Geisslinger G, Channon K, Watschinger K, Tegeder I. Mast cell tetrahydrobiopterin contributes to itch in mice. J Cell Mol Med 2019; 23:985-1000. [PMID: 30450838 PMCID: PMC6349351 DOI: 10.1111/jcmm.13999] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 09/25/2018] [Accepted: 10/13/2018] [Indexed: 12/28/2022] Open
Abstract
GTP cyclohydrolase (GCH1) governs de novo synthesis of the enzyme cofactor, tetrahydrobiopterin (BH4), which is essential for biogenic amine production, bioactive lipid metabolism and redox coupling of nitric oxide synthases. Overproduction of BH4 via upregulation of GCH1 in sensory neurons is associated with nociceptive hypersensitivity in rodents, and neuron-specific GCH1 deletion normalizes nociception. The translational relevance is revealed by protective polymorphisms of GCH1 in humans, which are associated with a reduced chronic pain. Because myeloid cells constitute a major non-neuronal source of BH4 that may contribute to BH4-dependent phenotypes, we studied here the contribution of myeloid-derived BH4 to pain and itch in lysozyme M Cre-mediated GCH1 knockout (LysM-GCH1-/- ) and overexpressing mice (LysM-GCH1-HA). Unexpectedly, knockout or overexpression in myeloid cells had no effect on nociceptive behaviour, but LysM-driven GCH1 knockout reduced, and its overexpression increased the scratching response in Compound 48/80 and hydroxychloroquine-evoked itch models, which involve histamine and non-histamine dependent signalling pathways. Mechanistically, GCH1 overexpression increased BH4, nitric oxide and hydrogen peroxide, and these changes were associated with increased release of histamine and serotonin and degranulation of mast cells. LysM-driven GCH1 knockout had opposite effects, and pharmacologic inhibition of GCH1 provided even stronger itch suppression. Inversely, intradermal BH4 provoked scratching behaviour in vivo and BH4 evoked an influx of calcium in sensory neurons. Together, these loss- and gain-of-function experiments suggest that itch in mice is contributed by BH4 release plus BH4-driven mediator release from myeloid immune cells, which leads to activation of itch-responsive sensory neurons.
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Affiliation(s)
- Katja Zschiebsch
- Institute of Clinical PharmacologyGoethe‐University HospitalFrankfurtGermany
| | - Caroline Fischer
- Institute of Clinical PharmacologyGoethe‐University HospitalFrankfurtGermany
| | | | - Gerd Geisslinger
- Institute of Clinical PharmacologyGoethe‐University HospitalFrankfurtGermany
| | - Keith Channon
- Division of Cardiovascular MedicineUniversity of OxfordOxfordUK
| | - Katrin Watschinger
- Division of Biological ChemistryBiocenterMedical University of InnsbruckInnsbruckAustria
| | - Irmgard Tegeder
- Institute of Clinical PharmacologyGoethe‐University HospitalFrankfurtGermany
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22
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McNeill E, Stylianou E, Crabtree MJ, Harrington-Kandt R, Kolb AL, Diotallevi M, Hale AB, Bettencourt P, Tanner R, O'Shea MK, Matsumiya M, Lockstone H, Müller J, Fletcher HA, Greaves DR, McShane H, Channon KM. Regulation of mycobacterial infection by macrophage Gch1 and tetrahydrobiopterin. Nat Commun 2018; 9:5409. [PMID: 30573728 PMCID: PMC6302098 DOI: 10.1038/s41467-018-07714-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 11/21/2018] [Indexed: 12/12/2022] Open
Abstract
Inducible nitric oxide synthase (iNOS) plays a crucial role in controlling growth of Mycobacterium tuberculosis (M.tb), presumably via nitric oxide (NO) mediated killing. Here we show that leukocyte-specific deficiency of NO production, through targeted loss of the iNOS cofactor tetrahydrobiopterin (BH4), results in enhanced control of M.tb infection; by contrast, loss of iNOS renders mice susceptible to M.tb. By comparing two complementary NO-deficient models, Nos2-/- mice and BH4 deficient Gch1fl/flTie2cre mice, we uncover NO-independent mechanisms of anti-mycobacterial immunity. In both murine and human leukocytes, decreased Gch1 expression correlates with enhanced cell-intrinsic control of mycobacterial infection in vitro. Gene expression analysis reveals that Gch1 deficient macrophages have altered inflammatory response, lysosomal function, cell survival and cellular metabolism, thereby enhancing the control of bacterial infection. Our data thus highlight the importance of the NO-independent functions of Nos2 and Gch1 in mycobacterial control.
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Affiliation(s)
- Eileen McNeill
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK.
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK.
| | | | - Mark J Crabtree
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | | | - Anna-Lena Kolb
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - Marina Diotallevi
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - Ashley B Hale
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | | | - Rachel Tanner
- Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK
| | | | | | - Helen Lockstone
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - Julius Müller
- Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK
| | - Helen A Fletcher
- Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - David R Greaves
- Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE, UK
| | - Helen McShane
- Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK
| | - Keith M Channon
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK.
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK.
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Cronin SJF, Seehus C, Weidinger A, Talbot S, Reissig S, Seifert M, Pierson Y, McNeill E, Longhi MS, Turnes BL, Kreslavsky T, Kogler M, Hoffmann D, Ticevic M, da Luz Scheffer D, Tortola L, Cikes D, Jais A, Rangachari M, Rao S, Paolino M, Novatchkova M, Aichinger M, Barrett L, Latremoliere A, Wirnsberger G, Lametschwandtner G, Busslinger M, Zicha S, Latini A, Robson SC, Waisman A, Andrews N, Costigan M, Channon KM, Weiss G, Kozlov AV, Tebbe M, Johnsson K, Woolf CJ, Penninger JM. The metabolite BH4 controls T cell proliferation in autoimmunity and cancer. Nature 2018; 563:564-568. [PMID: 30405245 PMCID: PMC6438708 DOI: 10.1038/s41586-018-0701-2] [Citation(s) in RCA: 158] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 09/20/2018] [Indexed: 12/17/2022]
Abstract
Genetic regulators and environmental stimuli modulate T cell activation in autoimmunity and cancer. The enzyme co-factor tetrahydrobiopterin (BH4) is involved in the production of monoamine neurotransmitters, the generation of nitric oxide, and pain1,2. Here we uncover a link between these processes, identifying a fundamental role for BH4 in T cell biology. We find that genetic inactivation of GTP cyclohydrolase 1 (GCH1, the rate-limiting enzyme in the synthesis of BH4) and inhibition of sepiapterin reductase (the terminal enzyme in the synthetic pathway for BH4) severely impair the proliferation of mature mouse and human T cells. BH4 production in activated T cells is linked to alterations in iron metabolism and mitochondrial bioenergetics. In vivo blockade of BH4 synthesis abrogates T-cell-mediated autoimmunity and allergic inflammation, and enhancing BH4 levels through GCH1 overexpression augments responses by CD4- and CD8-expressing T cells, increasing their antitumour activity in vivo. Administration of BH4 to mice markedly reduces tumour growth and expands the population of intratumoral effector T cells. Kynurenine-a tryptophan metabolite that blocks antitumour immunity-inhibits T cell proliferation in a manner that can be rescued by BH4. Finally, we report the development of a potent SPR antagonist for possible clinical use. Our data uncover GCH1, SPR and their downstream metabolite BH4 as critical regulators of T cell biology that can be readily manipulated to either block autoimmunity or enhance anticancer immunity.
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Affiliation(s)
- Shane J F Cronin
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
| | - Corey Seehus
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
| | - Adelheid Weidinger
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Center, Vienna, Austria
| | - Sebastien Talbot
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Département de Pharmacologie et Physiologie, Université de Montréal, Montréal, Québec, Canada
| | - Sonja Reissig
- Institute for Molecular Medicine, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Markus Seifert
- Department of Internal Medicine II (Infectious Diseases, Immunology, Rheumatology and Pneumology), Medical University of Innsbruck, Innsbruck, Austria
| | - Yann Pierson
- Institute of Chemical Sciences and Engineering, Institute of Bioengineering, National Centre of Competence in Research (NCCR) in Chemical Biology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Eileen McNeill
- Division of Cardiovascular Medicine, British Heart Foundation Centre for Research Excellence, John Radcliffe Hospital, University of Oxford, Oxford, UK
- Wellcome Trust Centre for Human Genetics, Roosevelt Drive, University of Oxford, Oxford, UK
| | - Maria Serena Longhi
- Division of Gastroenterology and Liver Center, Department of Medicine, Beth Israel Deaconess Medical Center (BIDMC) and Harvard Medical School (HMS), Harvard University, Boston, MA, USA
| | - Bruna Lenfers Turnes
- LABOX, Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Taras Kreslavsky
- Research Institute of Molecular Pathology, Vienna Biocenter, Campus-Vienna-Biocenter 1, Vienna, Austria
- Karolinska Institute, Department of Medicine Solna, Center for Molecular Medicine, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Melanie Kogler
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - David Hoffmann
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - Melita Ticevic
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - Débora da Luz Scheffer
- LABOX, Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Luigi Tortola
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - Domagoj Cikes
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - Alexander Jais
- Department of Neuronal Control of Metabolism, Max Planck Institute for Metabolism Research, Cologne, Germany
| | - Manu Rangachari
- Department of Neurosciences, Centre de Recherche de CHU de Québec-Université Laval, Québec, Québec, Canada
- Department of Molecular Medicine, Faculty of Medicine, Université Laval, Québec, Quebec, Canada
| | - Shuan Rao
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria
| | - Magdalena Paolino
- Karolinska Institute, Department of Medicine Solna, Center for Molecular Medicine, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Maria Novatchkova
- Research Institute of Molecular Pathology, Vienna Biocenter, Campus-Vienna-Biocenter 1, Vienna, Austria
| | - Martin Aichinger
- Research Institute of Molecular Pathology, Vienna Biocenter, Campus-Vienna-Biocenter 1, Vienna, Austria
| | - Lee Barrett
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
| | - Alban Latremoliere
- Neurosurgery Department, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | | | | | - Meinrad Busslinger
- Research Institute of Molecular Pathology, Vienna Biocenter, Campus-Vienna-Biocenter 1, Vienna, Austria
| | - Stephen Zicha
- Quartet Medicine, 400 Technology Square, Cambridge, MA, USA
| | - Alexandra Latini
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- LABOX, Departamento de Bioquímica, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Simon C Robson
- Division of Cardiovascular Medicine, British Heart Foundation Centre for Research Excellence, John Radcliffe Hospital, University of Oxford, Oxford, UK
- Wellcome Trust Centre for Human Genetics, Roosevelt Drive, University of Oxford, Oxford, UK
| | - Ari Waisman
- Institute for Molecular Medicine, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Nick Andrews
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
| | - Michael Costigan
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Anesthesia, Harvard Medical School, Boston, MA, USA
- Boston Children's Hospital, Boston, MA, USA
| | - Keith M Channon
- Division of Cardiovascular Medicine, British Heart Foundation Centre for Research Excellence, John Radcliffe Hospital, University of Oxford, Oxford, UK
- Wellcome Trust Centre for Human Genetics, Roosevelt Drive, University of Oxford, Oxford, UK
| | - Guenter Weiss
- Department of Internal Medicine II (Infectious Diseases, Immunology, Rheumatology and Pneumology), Medical University of Innsbruck, Innsbruck, Austria
| | - Andrey V Kozlov
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Center, Vienna, Austria
| | - Mark Tebbe
- Department of Molecular Medicine, Faculty of Medicine, Université Laval, Québec, Quebec, Canada
| | - Kai Johnsson
- Institute of Chemical Sciences and Engineering, Institute of Bioengineering, National Centre of Competence in Research (NCCR) in Chemical Biology, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
- Department of Chemical Biology, Max-Planck Institute for Medical Research, Heidelberg, Germany
| | - Clifford J Woolf
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA.
- FM Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA.
| | - Josef M Penninger
- IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Vienna, Austria.
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Tang Z, Liu L, Guo Y, Deng G, Chen M, Wei J. Exendin‑4 reverses endothelial dysfunction in mice fed a high‑cholesterol diet by a GTP cyclohydrolase‑1/tetrahydrobiopterin pathway. Mol Med Rep 2018; 18:3350-3358. [PMID: 30085331 PMCID: PMC6102738 DOI: 10.3892/mmr.2018.9345] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 06/26/2018] [Indexed: 12/25/2022] Open
Abstract
The present study examined whether exendin‑4 (Ex4) can improve the endothelial dysfunction of apolipoprotein E knockout (APOE‑KO) mice fed a high‑cholesterol diet and the potential mechanism by which it acts. Genetically wild‑type (WT) C57BL/6 mice and APOE‑KO mice of C57BL/6 background, were each randomly assigned to receive either Ex4 treatment (Ex4‑treated, for 8 weeks) or not (control). The 4 groups were fed the same high‑cholesterol diet for 8 weeks. The following were measured at the end of the eighth week: Endothelium‑dependent vasodilation of the arteries; plasma nitric oxide (NO) and metabolic index; levels of endothelial NO synthase (eNOS); phosphorylated eNOS (p‑eNOS; Ser‑1,177); guanosine triphosphate cyclohydrolase‑1 (GCH1); and tetrahydrobiopterin (THB). Ex4 treatment was associated with higher p‑eNOS levels in the WT group and in the APOE‑KO group, and higher vascular expression of GCH1 and higher arterial THB content, compared with baseline values. The results of the present study suggested that Ex4 may exert cardioprotective effects by reversing high‑cholesterol diet‑induced endothelial dysfunction in APOE‑KO mice. The protective mechanism is probably associated with the promotion of the expression levels of GCH1 protein and THB that maintain the normal function of eNOS.
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Affiliation(s)
- Zhiqi Tang
- Department of Cardiology, The First People's Hospital of Nanning City, Nanning, Guangxi 530021, P.R. China
| | - Lijuan Liu
- School of Continuing Education, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Yujie Guo
- Department of Cardiology, The People's Hospital of Liuzhou City, Liuzhou, Guangxi 545006, P.R. China
| | - Guoxiong Deng
- Department of Cardiology, The First People's Hospital of Nanning City, Nanning, Guangxi 530021, P.R. China
| | - Meixiang Chen
- Department of Cardiology, The First People's Hospital of Nanning City, Nanning, Guangxi 530021, P.R. China
| | - Jinru Wei
- Department of Cardiology, The First People's Hospital of Nanning City, Nanning, Guangxi 530021, P.R. China
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25
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Douglas G, Hale AB, Patel J, Chuaiphichai S, Al Haj Zen A, Rashbrook VS, Trelfa L, Crabtree MJ, McNeill E, Channon KM. Roles for endothelial cell and macrophage Gch1 and tetrahydrobiopterin in atherosclerosis progression. Cardiovasc Res 2018; 114:1385-1399. [PMID: 29596571 PMCID: PMC6054219 DOI: 10.1093/cvr/cvy078] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 02/22/2018] [Accepted: 03/26/2018] [Indexed: 12/17/2022] Open
Abstract
Aims GTP cyclohydrolase I catalyses the first and rate-limiting reaction in the synthesis of tetrahydrobiopterin (BH4), an essential cofactor for nitric oxide synthases (NOS). Both eNOS and iNOS have been implicated in the progression of atherosclerosis, with opposing effects in eNOS and iNOS knockout mice. However, the pathophysiologic requirement for BH4 in regulating both eNOS and iNOS function, and the effects of loss of BH4 on the progression of atherosclerosis remains unknown. Methods and results Hyperlipidemic mice deficient in Gch1 in endothelial cells and leucocytes were generated by crossing Gch1fl/flTie2cre mice with ApoE-/- mice. Deficiency of Gch1 and BH4 in endothelial cells and myeloid cells was associated with mildly increased blood pressure. High fat feeding for 6 weeks in Gch1fl/flTie2CreApoE-/- mice resulted in significantly decreased circulating BH4 levels, increased atherosclerosis burden and increased plaque macrophage content. Gch1fl/flTie2CreApoE-/- mice showed hallmarks of endothelial cell dysfunction, with increased aortic VCAM-1 expression and decreased endothelial cell dependent vasodilation. Furthermore, loss of BH4 from pro-inflammatory macrophages resulted in increased foam cell formation and altered cellular redox signalling, with decreased expression of antioxidant genes and increased reactive oxygen species. Bone marrow chimeras revealed that loss of Gch1 in both endothelial cells and leucocytes is required to accelerate atherosclerosis. Conclusion Both endothelial cell and macrophage BH4 play important roles in the regulation of NOS function and cellular redox signalling in atherosclerosis.
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Affiliation(s)
- Gillian Douglas
- Division of Cardiovascular Medicine, BHF Centre of Research Excellence, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Ashley B Hale
- Division of Cardiovascular Medicine, BHF Centre of Research Excellence, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Jyoti Patel
- Division of Cardiovascular Medicine, BHF Centre of Research Excellence, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Surawee Chuaiphichai
- Division of Cardiovascular Medicine, BHF Centre of Research Excellence, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Ayman Al Haj Zen
- Division of Cardiovascular Medicine, BHF Centre of Research Excellence, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Victoria S Rashbrook
- Division of Cardiovascular Medicine, BHF Centre of Research Excellence, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Lucy Trelfa
- Division of Cardiovascular Medicine, BHF Centre of Research Excellence, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Mark J Crabtree
- Division of Cardiovascular Medicine, BHF Centre of Research Excellence, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Eileen McNeill
- Division of Cardiovascular Medicine, BHF Centre of Research Excellence, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Keith M Channon
- Division of Cardiovascular Medicine, BHF Centre of Research Excellence, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
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26
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Tran AN, Walker K, Harrison DG, Chen W, Mobley J, Hocevar L, Hackney JR, Sedaka RS, Pollock JS, Goldberg MS, Hambardzumyan D, Cooper SJ, Gillespie Y, Hjelmeland AB. Reactive species balance via GTP cyclohydrolase I regulates glioblastoma growth and tumor initiating cell maintenance. Neuro Oncol 2018; 20:1055-1067. [PMID: 29409010 PMCID: PMC6280150 DOI: 10.1093/neuonc/noy012] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Background Depending on the level, differentiation state, and tumor stage, reactive nitrogen and oxygen species inhibit or increase cancer growth and tumor initiating cell maintenance. The rate-limiting enzyme in a pathway that can regulate reactive species production but has not been thoroughly investigated in glioblastoma (GBM; grade IV astrocytoma) is guanosine triphosphate (GTP) cyclohydrolase 1 (GCH1). We sought to define the role of GCH1 in the regulation of GBM growth and brain tumor initiating cell (BTIC) maintenance. Methods We examined GCH1 mRNA and protein expression in patient-derived xenografts, clinical samples, and glioma gene expression datasets. GCH1 levels were modulated using lentiviral expression systems, and effects on cell growth, self-renewal, reactive species production, and survival in orthotopic patient-derived xenograft models were determined. Results GCH1 was expressed in GBMs with elevated but not exclusive RNA and protein levels in BTICs in comparison to non-BTICs. Overexpression of GCH1 in GBM cells increased cell growth in vitro and decreased survival in an intracranial GBM mouse model. In converse experiments, GCH1 knockdown with short hairpin RNA led to GBM cell growth inhibition and reduced self-renewal in association with decreased CD44 expression. GCH1 was critical for controlling reactive species balance, including suppressing reactive oxygen species production, which mediated GCH1 cell growth effects. In silico analyses demonstrated that higher GCH1 levels in glioma patients correlate with higher glioma grade, recurrence, and worse survival. Conclusions GCH1 expression in established GBMs is pro-tumorigenic, causing increased growth due, in part, to promotion of BTIC maintenance and suppression of reactive oxygen species.
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Affiliation(s)
- Anh Nhat Tran
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Kiera Walker
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - David G Harrison
- Division of Clinical Pharmacology, Vanderbilt University, Nashville, Tennessee
| | - Wei Chen
- Division of Clinical Pharmacology, Vanderbilt University, Nashville, Tennessee
| | - James Mobley
- Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama
| | - Lauren Hocevar
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - James R Hackney
- Division of Neuropathology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Randee S Sedaka
- Division of Nephrology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Jennifer S Pollock
- Division of Nephrology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Matthew S Goldberg
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| | | | - Sara J Cooper
- HudsonAlpha Institute for Biotechnology, Huntsville, Alabama
| | - Yancey Gillespie
- Department of Neurosurgery, University of Alabama at Birmingham, Birmingham, Alabama
| | - Anita B Hjelmeland
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
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Nasser A, Møller AT, Hellmund V, Thorborg SS, Jespersgaard C, Bjerrum OJ, Dupont E, Nachman G, Lykkesfeldt J, Jensen TS, Møller LB. Heterozygous mutations in GTP-cyclohydrolase-1 reduce BH4 biosynthesis but not pain sensitivity. Pain 2018; 159:1012-1024. [PMID: 29470312 DOI: 10.1097/j.pain.0000000000001175] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Human studies have demonstrated a correlation between noncoding polymorphisms of "the pain protective" haplotype in the GCH1 gene that encodes for GTP cyclohydrolase I (GTPCH1)-which leads to reduced tetrahydrobiopterin (BH4) production in cell systems-and a diminished perception of experimental and clinical pain. Here, we investigate whether heterozygous mutations in the GCH1 gene which lead to a profound BH4 reduction in patients with dopa-responsive dystonia (DRD) have any effect on pain sensitivity. The study includes an investigation of GCH1-associated biomarkers and pain sensitivity in a cohort of 22 patients with DRD and 36 controls. The patients with DRD had, when compared with controls, significantly reduced levels of BH4, neopterin, biopterin, and GTPCH1 in their urine, blood, or cytokine-stimulated fibroblasts, but their pain response with respect to non-painful stimulation, (acute) stimulus-evoked pain, or pain response after capsaicin-induced sensitization was not significantly different. A family-specific cohort of 11 patients with DRD and 11 controls were included in this study. The patients with DRD were heterozygous for the pain protective haplotype in cis with the GCH1 disease-causing mutation, c.899T>C. No effect on pain perception was observed for this combined haplotype. In conclusion, a reduced concentration of BH4 is not sufficient to alter ongoing pain sensitivity or evoked pain responses.
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Affiliation(s)
- Arafat Nasser
- Applied Human Molecular Genetics, Clinical Genetic Clinic, Kennedy Center, Copenhagen University Hospital, Rigshospitalet, Glostrup, Denmark
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen Ø, Denmark
| | - Anette Torvin Møller
- Department of Neurology, Danish Pain Research Center, Aarhus University Hospital, Århus, Denmark
| | - Vibe Hellmund
- Department of Neurology, Danish Pain Research Center, Aarhus University Hospital, Århus, Denmark
| | - Sidsel Salling Thorborg
- Applied Human Molecular Genetics, Clinical Genetic Clinic, Kennedy Center, Copenhagen University Hospital, Rigshospitalet, Glostrup, Denmark
| | - Cathrine Jespersgaard
- Applied Human Molecular Genetics, Clinical Genetic Clinic, Kennedy Center, Copenhagen University Hospital, Rigshospitalet, Glostrup, Denmark
| | - Ole J Bjerrum
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen Ø, Denmark
| | - Erik Dupont
- Department of Neurology, Aarhus University Hospital, Århus, Denmark
| | - Gösta Nachman
- Department of Biology, Section of Ecology and Evolution, University of Copenhagen, Copenhagen Ø, Denmark
| | - Jens Lykkesfeldt
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - Troels Staehelin Jensen
- Department of Neurology, Danish Pain Research Center, Aarhus University Hospital, Århus, Denmark
| | - Lisbeth Birk Møller
- Applied Human Molecular Genetics, Clinical Genetic Clinic, Kennedy Center, Copenhagen University Hospital, Rigshospitalet, Glostrup, Denmark
- Department of Science and Environment, Roskilde University, Roskilde, Denmark
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28
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Abdelghany TM, Ismail RS, Mansoor FA, Zweier JR, Lowe F, Zweier JL. Cigarette smoke constituents cause endothelial nitric oxide synthase dysfunction and uncoupling due to depletion of tetrahydrobiopterin with degradation of GTP cyclohydrolase. Nitric Oxide 2018; 76:113-121. [PMID: 29524646 DOI: 10.1016/j.niox.2018.02.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 01/12/2018] [Accepted: 02/28/2018] [Indexed: 12/13/2022]
Abstract
Cigarette smoking (CS) is a well-established risk factor for cardiovascular disease (CVD). Endothelial dysfunction (ED) with loss of nitric oxide (NO) production is a central mechanism leading to the advent of CVD. Despite many prior studies of this major health problem, the exact mechanism by which CS induces ED is not well understood. This study examines the mechanism by which CS induces ED with altered endothelial NO synthase (eNOS) function in aortic endothelial cells (AECs). Exposure of AECs to cigarette smoke extract (CSE) resulted in a marked decrease in NO production with concomitant increase in superoxide (O2.-) generation and accumulation of 4-hydroxy-2-nonenal protein adducts. CSE exposure led to depletion of the essential eNOS cofactor tetrahydrobiopterin (BH4) as well as total biopterin levels and decreased the expression level of guanosine triphosphate cyclohydrolase (GTPCH), the rate limiting enzyme in BH4 biosynthesis. Moreover, exposure of AECs to CSE increased the level of ubiquitinated proteins and increased 26 S proteasomal activity in a concentration-dependent manner. Pre-treatment with MG132, a 26 S proteasome inhibitor, partially prevented CSE-induced loss of BH4, total biopterin, GTPCH, and increased NO production following CSE exposure, indicating a role of the ubiquitin-proteasome system in CSE-induced eNOS dysfunction. In conclusion, CSE-induced eNOS dysfunction and uncoupling occurs due to BH4 depletion with BH4de novo synthesis limited by diminished GTPCH expression.
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Affiliation(s)
- Tamer M Abdelghany
- Department of Pharmacology and Toxicology, College of Pharmacy, Al-Azhar University, Cairo, Egypt
| | - Raed S Ismail
- Department of Pharmacology and Toxicology, College of Pharmacy, Al-Azhar University, Cairo, Egypt
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29
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Wei J, Zhang Y, Li Z, Wang X, Chen L, Du J, Liu J, Liu J, Hou Y. GCH1 attenuates cardiac autonomic nervous remodeling in canines with atrial-tachypacing via tetrahydrobiopterin pathway regulated by microRNA-206. Pacing Clin Electrophysiol 2018; 41:459-471. [PMID: 29436714 DOI: 10.1111/pace.13289] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 01/04/2018] [Accepted: 01/15/2018] [Indexed: 12/22/2022]
Abstract
BACKGROUND/AIMS Cardiac autonomic nerve remodeling (ANR) is an important mechanism of atrial fibrillation (AF). GTP cyclohydrolase I, encoded by GCH1, is the rate-limiting enzyme in de novo synthesis of tetrahydrobiopterin (BH4), an essential cofactor for nitric oxide (NO) synthesis. Previous studies reported that increased BH4 and NO content negatively regulated nerve regeneration. This study investigated the effects of GCH1 on ANR via BH4 pathway, regulated by microRNA-206 (miR-206). METHODS AND RESULTS In canines, atrial tachypacing (A-TP), together with miR-206 overexpression, increased PGP9.5 level and inhibited GCH1 expression by quantitative real-time polymerase chain reaction and western blot analysis. GCH1 was validated to be a direct target of miR-206 by luciferase assays. Meanwhile, miR-206 overexpression by lentiviruses infection into right superior pulmonary vein fat pad decreased GCH1 expression to ∼40% and further reduced BH4 and NO content compared with the control canines. After infection of GCH1 overexpression lentiviruses for two weeks, atrial effective refractory period was increased compared with the control group (105.8 ± 1.537 ms vs 99.17 ± 2.007 ms, P < 0.05). Moreover, GCH1 overexpression attenuated canines' atrial PGP9.5 level to ∼56% of the controls. In myocardial cells, transfection of GCH1 overexpression lentiviruses also decreased PGP9.5 expression to 26% of the control group. In patients, plasma was collected and miR-206 expression was upregulated in AF patients (n = 18) than the controls (n = 12). CONCLUSIONS Our findings suggested that GCH1 downregulation exacerbated ANR by decreasing atrial BH4 and NO content modulated by miR-206 in A-TP canines. This indicates that GCH1 may prevent the initiation of AF through inhibiting ANR.
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Affiliation(s)
- Jinqiu Wei
- Department of Examination Center, Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Yujiao Zhang
- Department of Cardiology, Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Zhan Li
- Department of Cardiology, Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Ximin Wang
- Department of Cardiology, Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Linlin Chen
- Department of Special Examination, Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Juanjuan Du
- Department of Cardiology, Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Jing Liu
- Medical Research Center, Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Ju Liu
- Medical Research Center, Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Yinglong Hou
- Department of Cardiology, Shandong Provincial Qianfoshan Hospital, Jinan, China
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Clelland JD, Read LL, Smeed J, Clelland CL. Regulation of cortical and peripheral GCH1 expression and biopterin levels in schizophrenia-spectrum disorders. Psychiatry Res 2018; 262:229-236. [PMID: 29471261 PMCID: PMC5866784 DOI: 10.1016/j.psychres.2018.02.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 01/19/2018] [Accepted: 02/02/2018] [Indexed: 12/17/2022]
Abstract
Tetrahydrobiopterin (BH4) is an essential cofactor for dopamine, serotonin and nitric oxide synthesis. Deficits of plasma total biopterin (a measure of BH4) have been described in schizophrenia and schizoaffective disorder. GCH1 encodes the first and rate-limiting enzyme in BH4 synthesis. Peripheral GCH1 expression is lower in first episode psychosis patients versus controls, and we hypothesized that a GCH1 promoter polymorphism associated with psychiatric illness, contributes to regulation of both GCH1 expression and BH4 levels. We tested this hypothesis in 120 subjects (85 patients with schizophrenia or schizoaffective disorder and 35 controls): Patients with the rs10137071 A allele had significantly lower plasma biopterin than GG patients and controls. In additional samples we assessed the relationship between genotype and diagnosis (schizophrenia or control) on GCH1 expression in the prefrontal cortex (n = 67) and peripheral leukocytes (n = 53). We found a significant linear relationship between GCH1 and study group in the CNS and periphery, with A allele patients having lower expression. Finally, in antipsychotic naïve patients (n = 13) we tested for an effect of medication on GCH1: Expression rose significantly after the onset of medication, primarily in A allele patients. These data suggest the potential for personalized genetic approaches to ameliorating BH4 deficits in schizophrenia-spectrum disorders.
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Affiliation(s)
- James D Clelland
- Movement Disorders and Molecular Psychiatry, The Nathan S. Kline Institute for Psychiatric Research, 140 Old Orangeburg Road, Orangeburg, NY, USA; Department of Psychiatry, New York University Langone Medical Center (NYU), 550 First Avenue, New York, NY, USA
| | - Laura L Read
- Movement Disorders and Molecular Psychiatry, The Nathan S. Kline Institute for Psychiatric Research, 140 Old Orangeburg Road, Orangeburg, NY, USA; Department of Psychiatry, New York University Langone Medical Center (NYU), 550 First Avenue, New York, NY, USA
| | - Jennifer Smeed
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, USA
| | - Catherine L Clelland
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, USA; Department of Pathology and Cell Biology, Columbia University Medical Center, 630 West 168th Street, New York, NY, USA.
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Abstract
Most attempts at rational development of new analgesics have failed, in part because chronic pain involves multiple processes that remain poorly understood. To improve translational success, one strategy is to select novel targets for which there is proof of clinical relevance, either genetically through heritable traits, or pharmacologically. Such an approach by definition yields targets with high clinical validity. The biology of these targets can be elucidated in animal models before returning to the patients with a refined therapeutic. For optimal treatment, having biomarkers of drug action available is also a plus. Here we describe a case study in rational drug design: the use of controlled inhibition of peripheral tetrahydrobiopterin (BH4) synthesis to reduce abnormal chronic pain states without altering nociceptive-protective pain. Initially identified in a population of patients with low back pain, the association between BH4 production and chronic pain has been confirmed in more than 12 independent cohorts, through a common haplotype (present in 25% of Caucasians) of the rate-limiting enzyme for BH4 synthesis, GTP cyclohydrolase 1 (GCH1). Genetic tools in mice have demonstrated that both injured sensory neurons and activated macrophages engage increased BH4 synthesis to cause chronic pain. GCH1 is an obligate enzyme for de novo BH4 production. Therefore, inhibiting GCH1 activity eliminates all BH4 production, affecting the synthesis of multiple neurotransmitters and signaling molecules and interfering with physiological function. In contrast, targeting the last enzyme of the BH4 synthesis pathway, sepiapterin reductase (SPR), allows reduction of pathological BH4 production without completely blocking physiological BH4 synthesis. Systemic SPR inhibition in mice has not revealed any safety concerns to date, and available genetic and pharmacologic data suggest similar responses in humans. Finally, because it is present in vivo only when SPR is inhibited, sepiapterin serves as a reliable biomarker of target engagement, allowing potential quantification of drug efficacy. The emerging development of therapeutics that target BH4 synthesis to treat chronic pain illustrates the power of combining human and mouse genetics: human genetic studies for clinical selection of relevant targets, coupled with causality studies in mice, allowing the rational engineering of new analgesics.
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Affiliation(s)
- Alban Latremoliere
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA, 02115, USA.
| | - Michael Costigan
- Kirby Neurobiology Center, Boston Children's Hospital and Department of Neurobiology, Harvard Medical School, Boston, MA, 02115, USA.
- Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, Boston, MA, 02115, USA.
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Dietl AM, Meir Z, Shadkchan Y, Osherov N, Haas H. Riboflavin and pantothenic acid biosynthesis are crucial for iron homeostasis and virulence in the pathogenic mold Aspergillus fumigatus. Virulence 2018; 9:1036-1049. [PMID: 30052132 PMCID: PMC6068542 DOI: 10.1080/21505594.2018.1482181] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 05/22/2018] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Aspergillus fumigatus is the most prevalent airborne fungal pathogen, causing invasive fungal infections mainly in immunosuppressed individuals. Death rates from invasive aspergillosis remain high because of limited treatment options and increasing antifungal resistance. The aim of this study was to identify key fungal-specific genes participating in vitamin B biosynthesis in A. fumigatus. Because these genes are absent in humans they can serve as possible novel targets for antifungal drug development. METHODS By sequence homology we identified, deleted and analysed four key A. fumigatus genes (riboB, panA, pyroA, thiB) involved respectively in the biosynthesis of riboflavin (vitamin B2), pantothenic acid (vitamin B5), pyridoxine (vitamin B6) and thiamine (vitamin B1). RESULTS Deletion of riboB, panA, pyroA or thiB resulted in respective vitamin auxotrophy. Lack of riboflavin and pantothenic acid biosynthesis perturbed many cellular processes including iron homeostasis. Virulence in murine pulmonary and systemic models of infection was severely attenuated following deletion of riboB and panA, strongly reduced after pyroA deletion and weakly attenuated after thiB deletion. CONCLUSIONS This study reveals the biosynthetic pathways of the vitamins riboflavin and pantothenic acid as attractive targets for novel antifungal therapy. Moreover, the virulence studies with auxotrophic mutants serve to identify the availability of nutrients to pathogens in host niches. ABBREVIATIONS BPS: bathophenanthrolinedisulfonate; BSA: bovine serum albumin; CFU: colony forming unit; -Fe: iron starvation; +Fe: iron sufficiency; hFe: high iron; NRPSs: nonribosomal peptide synthetases; PKSs: polyketide synthaseses; wt: wild type.
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Affiliation(s)
- Anna-Maria Dietl
- Division of Molecular Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Zohar Meir
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine Ramat-Aviv, Tel-Aviv, Israel
| | - Yona Shadkchan
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine Ramat-Aviv, Tel-Aviv, Israel
| | - Nir Osherov
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine Ramat-Aviv, Tel-Aviv, Israel
| | - Hubertus Haas
- Division of Molecular Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
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Vasquez-Vivar J, Shi Z, Luo K, Thirugnanam K, Tan S. Tetrahydrobiopterin in antenatal brain hypoxia-ischemia-induced motor impairments and cerebral palsy. Redox Biol 2017; 13:594-599. [PMID: 28803128 PMCID: PMC5554922 DOI: 10.1016/j.redox.2017.08.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 07/28/2017] [Accepted: 08/01/2017] [Indexed: 12/24/2022] Open
Abstract
Antenatal brain hypoxia-ischemia, which occurs in cerebral palsy, is considered a significant cause of motor impairments in children. The mechanisms by which antenatal hypoxia-ischemia causes brain injury and motor deficits still need to be elucidated. Tetrahydrobiopterin is an important enzyme cofactor that is necessary to produce neurotransmitters and to maintain the redox status of the brain. A genetic deficiency of this cofactor from mutations of biosynthetic or recycling enzymes is a well-recognized factor in the development of childhood neurological disorders characterized by motor impairments, developmental delay, and encephalopathy. Experimental hypoxia-ischemia causes a decline in the availability of tetrahydrobiopterin in the immature brain. This decline coincides with the loss of brain function, suggesting this occurrence contributes to neuronal dysfunction and motor impairments. One possible mechanism linking tetrahydrobiopterin deficiency, hypoxia-ischemia, and neuronal injury is oxidative injury. Evidence of the central role of the developmental biology of tetrahydrobiopterin in response to hypoxic ischemic brain injury, especially the development of motor deficits, is discussed.
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Affiliation(s)
- Jeannette Vasquez-Vivar
- Department of Biophysics and Redox Biology Program, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
| | - Zhongjie Shi
- Wayne State University School of Medicine and Children's Hospital of Michigan, 3901 Beaubien, Room 5177, Carls Bldg., Detroit, MI 48201, USA
| | - Kehuan Luo
- Wayne State University School of Medicine and Children's Hospital of Michigan, 3901 Beaubien, Room 5177, Carls Bldg., Detroit, MI 48201, USA
| | - Karthikeyan Thirugnanam
- Department of Biophysics and Redox Biology Program, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Sidhartha Tan
- Wayne State University School of Medicine and Children's Hospital of Michigan, 3901 Beaubien, Room 5177, Carls Bldg., Detroit, MI 48201, USA.
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Ryu MY, Lee MA, Ahn YH, Kim KS, Yoon SH, Snyder EY, Cho KG, Kim SU. Brain Transplantation of Neural Stem Cells Cotransduced with Tyrosine Hydroxylase and GTP Cyclohydrolase 1 in Parkinsonian Rats. Cell Transplant 2017; 14:193-202. [PMID: 15929554 DOI: 10.3727/000000005783983133] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Neural stem cells (NSCs) of the central nervous system (CNS) recently have attracted a great deal of interest not only because of their importance in basic research on neural development, but also in terms of their therapeutic potential in neurological diseases, such as Parkinson's disease (PD). To examine if genetically modified NSCs are a suitable source for the cell and gene therapy of PD, an immortalized mouse NSC line, C17.2, was transduced with tyrosine hydroxylase (TH) gene and with GTP cyclohydrolase 1 (GTPCH1) gene, which are important enzymes in dopamine biosynthesis. The expression of TH in transduced C17.2-THGC cells was confirmed by RT-PCR, Western blot analysis, and immunocytochemistry, and expression of GTPCH1 by RT-PCR. The level of L-DOPA released by C17.2-THGC cells, as determined by HPLC assay, was 3793 pmol/106 cells, which is 760-fold higher than that produced by C17.2-TH cells, indicating that GTPCH1 expression is important for L-DOPA production by transduced C17.2 cells. Following the implantation of C17.2-THGcC NSCs into the striata of parkinsonian rats, a marked improvement in amphetamine-induced turning behavior was observed in parkinsonian rats grafted with C17.2-THGC cells but not in the control rats grafted with C17.2 cells. These results indicate that genetically modified NSCs grafted into the brain of the parkinsonian rats are capable of survival, migration, and neuronal differentiation. Collectively, these results suggest that NSCs have great potential as a source of cells for cell therapy and an effective vehicle for therapeutic gene transfer in Parkinson's disease.
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Affiliation(s)
- M Y Ryu
- Department of Neurosurgery, Ajou University School of Medicine, Suwon, Korea
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Chuaiphichai S, Crabtree MJ, Mcneill E, Hale AB, Trelfa L, Channon KM, Douglas G. A key role for tetrahydrobiopterin-dependent endothelial NOS regulation in resistance arteries: studies in endothelial cell tetrahydrobiopterin-deficient mice. Br J Pharmacol 2017; 174:657-671. [PMID: 28128438 PMCID: PMC5368052 DOI: 10.1111/bph.13728] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 01/22/2017] [Accepted: 01/23/2017] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND AND PURPOSE The cofactor tetrahydrobiopterin (BH4) is a critical regulator of endothelial NOS (eNOS) function, eNOS-derived NO and ROS signalling in vascular physiology. To determine the physiological requirement for de novo endothelial cell BH4 synthesis for the vasomotor function of resistance arteries, we have generated a mouse model with endothelial cell-specific deletion of Gch1, encoding GTP cyclohydrolase 1 (GTPCH), an essential enzyme for BH4 biosynthesis, and evaluated BH4-dependent eNOS regulation, eNOS-derived NO and ROS generation. EXPERIMENTAL APPROACH The reactivity of mouse second-order mesenteric arteries was assessed by wire myography. High performance liquid chromatography was used to determine BH4, BH2 and biopterin. Western blotting was used for expression analysis. KEY RESULTS Gch1fl/fl Tie2cre mice demonstrated reduced GTPCH protein and BH4 levels in mesenteric arteries. Deficiency in endothelial cell BH4 leads to eNOS uncoupling, increased ROS production and loss of NO generation in mesenteric arteries of Gch1fl/fl Tie2cre mice. Gch1fl/fl Tie2cre mesenteric arteries had enhanced vasoconstriction to U46619 and phenylephrine, which was abolished by L-NAME. Endothelium-dependent vasodilatations to ACh and SLIGRL were impaired in mesenteric arteries from Gch1fl/fl Tie2cre mice, compared with those from wild-type littermates. Loss of eNOS-derived NO-mediated vasodilatation was associated with increased eNOS-derived H2 O2 and cyclooxygenase-derived vasodilator in Gch1fl/fl Tie2cre mesenteric arteries. CONCLUSIONS AND IMPLICATIONS Endothelial cell Gch1 and BH4-dependent eNOS regulation play pivotal roles in maintaining vascular homeostasis in resistance arteries. Therefore, targeting vascular Gch1 and BH4 biosynthesis may provide a novel therapeutic target for the prevention and treatment of microvascular dysfunction in patients with cardiovascular disease.
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Affiliation(s)
- Surawee Chuaiphichai
- British Heart Foundation Centre of Research Excellence, Division of Cardiovascular MedicineUniversity of OxfordOxfordUK
- Wellcome Trust Centre for Human GeneticsUniversity of OxfordOxfordUK
| | - Mark J Crabtree
- British Heart Foundation Centre of Research Excellence, Division of Cardiovascular MedicineUniversity of OxfordOxfordUK
- Wellcome Trust Centre for Human GeneticsUniversity of OxfordOxfordUK
| | - Eileen Mcneill
- British Heart Foundation Centre of Research Excellence, Division of Cardiovascular MedicineUniversity of OxfordOxfordUK
- Wellcome Trust Centre for Human GeneticsUniversity of OxfordOxfordUK
| | - Ashley B Hale
- British Heart Foundation Centre of Research Excellence, Division of Cardiovascular MedicineUniversity of OxfordOxfordUK
- Wellcome Trust Centre for Human GeneticsUniversity of OxfordOxfordUK
| | - Lucy Trelfa
- British Heart Foundation Centre of Research Excellence, Division of Cardiovascular MedicineUniversity of OxfordOxfordUK
- Wellcome Trust Centre for Human GeneticsUniversity of OxfordOxfordUK
| | - Keith M Channon
- British Heart Foundation Centre of Research Excellence, Division of Cardiovascular MedicineUniversity of OxfordOxfordUK
- Wellcome Trust Centre for Human GeneticsUniversity of OxfordOxfordUK
| | - Gillian Douglas
- British Heart Foundation Centre of Research Excellence, Division of Cardiovascular MedicineUniversity of OxfordOxfordUK
- Wellcome Trust Centre for Human GeneticsUniversity of OxfordOxfordUK
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Bai YP, Xiao S, Tang YB, Tan Z, Tang H, Ren Z, Zeng H, Yang Z. Shear stress-mediated upregulation of GTP cyclohydrolase/tetrahydrobiopterin pathway ameliorates hypertension-related decline in reendothelialization capacity of endothelial progenitor cells. J Hypertens 2017; 35:784-797. [PMID: 28033126 DOI: 10.1097/hjh.0000000000001216] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
OBJECTIVES Guanosine triphosphate cyclohydrolase/tetrahydrobiopterin (GTPCH)/(BH4) pathway has been proved to regulate the function of endothelial progenitor cells (EPCs) in deoxycorticosterone acetate-salt hypertensive mice, indicating that GTPCH/BH4 pathway may be an important repair target for hypertension-related endothelial injury. Shear stress is an important nonpharmacologic strategy to modulate the function of EPCs. Here, we investigated the effects of laminar shear stress on the GTPCH/BH4 pathway and endothelial repair capacity of circulating EPCs in hypertension. METHOD Laminar shear stress was loaded on the human EPCs from hypertensive patients and normotensive patients. The in-vitro function, in-vivo reendothelialization capacity and GTPCH/BH4 pathway of human EPCs were evaluated. RESULTS Both in-vitro function and reendothelialization capacity of EPCs were lower in hypertensive patients than that in normotensive patients. The GTPCH/BH4 pathway of EPCs was downregulated in hypertensive patients. Shear stress increased in-vitro function and reendothelialization capacity of EPCs from hypertensive patients and normotensive patients. Furthermore, shear stress upregulated the expression of GTPCH I and levels of BH4, nitric oxide, and cGMP of EPCs, and reduced thrombospondin-1 expression. With treatment of GTPCH knockdown or nitroarginine methyl ester inhibition, shear stress-induced increased levels of BH4, nitric oxide and cGMP of EPCs was suppressed. When GTPCH/BH4 pathway of EPCs was blocked, the effects of shear stress on in-vitro function and reendothelialization capacity of EPCs were inhibited. CONCLUSION The study demonstrates for the first time that shear stress-induced upregulation of the GTPCH/BH4 pathway ameliorates hypertension-related decline in endothelial repair capacity of EPCs. These findings provide novel nonpharmacologic therapeutic approach for hypertension-related endothelial repair.
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Affiliation(s)
- Yong-Ping Bai
- aDepartment of Geriatric Medicine, Xiangya Hospital, Central South University, Changsha, Hunan bDepartment of Neurology, Sun Yat-Sen Memorial Hospital cDepartment of Pharmacology, Zhongshan School of Medicine dDepartment of Physiology, Zhongshan School of Medicine, Sun Yat-Sen University eSun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine fCenter for Reproductive Medicine, The Sixth Affiliated Hospital gDepartment of Hypertension & Vascular Disease, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong, People's Republic of China
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Bailey J, Shaw A, Fischer R, Ryan BJ, Kessler BM, McCullagh J, Wade-Martins R, Channon KM, Crabtree MJ. A novel role for endothelial tetrahydrobiopterin in mitochondrial redox balance. Free Radic Biol Med 2017; 104:214-225. [PMID: 28104455 PMCID: PMC5338462 DOI: 10.1016/j.freeradbiomed.2017.01.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 01/04/2017] [Accepted: 01/06/2017] [Indexed: 02/07/2023]
Abstract
The redox co-factor tetrahydrobiopterin (BH4) regulates nitric oxide (NO) and reactive oxygen species (ROS) production by endothelial NOS (eNOS) and is an important redox-dependent signalling molecule in the endothelium. Loss of endothelial BH4 is observed in cardiovascular disease (CVD) states and results in decreased NO and increased superoxide (O2-) generation via eNOS uncoupling. Genetic mouse models of augmented endothelial BH4 synthesis have shown proof of concept that endothelial BH4 can alter CVD pathogenesis. However, clinical trials of BH4 therapy in vascular disease have been limited by systemic oxidation, highlighting the need to explore the wider roles of BH4 to find novel therapeutic targets. In this study, we aimed to elucidate the effects of BH4 deficiency on mitochondrial function and bioenergetics using targeted knockdown of the BH4 synthetic enzyme, GTP Cyclohydrolase I (GTPCH). Knockdown of GTPCH by >90% led to marked loss of cellular BH4 and a striking induction of O2- generation in the mitochondria of murine endothelial cells. This effect was likewise observed in BH4-depleted fibroblasts devoid of NOS, indicating a novel NOS-independent role for BH4 in mitochondrial redox signalling. Moreover, this BH4-dependent, mitochondria-derived ROS further oxidised mitochondrial BH4, concomitant with changes in the thioredoxin and glutathione antioxidant pathways. These changes were accompanied by a modest increase in mitochondrial size, mildly attenuated basal respiratory function, and marked changes in the mitochondrial proteome and cellular metabolome, including the accumulation of the TCA intermediate succinate. Taken together, these data reveal a novel NOS-independent role for BH4 in the regulation of mitochondrial redox signalling and bioenergetic metabolism.
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Affiliation(s)
- Jade Bailey
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, United Kingdom
| | - Andrew Shaw
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, United Kingdom
| | - Roman Fischer
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, United Kingdom
| | - Brent J Ryan
- Oxford Parkinson's Disease Centre, Department of Physiology, Anatomy and Genetics, South Parks Road, Oxford OX1 3QX, United Kingdom
| | - Benedikt M Kessler
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, United Kingdom
| | - James McCullagh
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Richard Wade-Martins
- Oxford Parkinson's Disease Centre, Department of Physiology, Anatomy and Genetics, South Parks Road, Oxford OX1 3QX, United Kingdom
| | - Keith M Channon
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, United Kingdom.
| | - Mark J Crabtree
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, United Kingdom
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Ke J, Wei R, Yu F, Zhang J, Hong T. Liraglutide restores angiogenesis in palmitate-impaired human endothelial cells through PI3K/Akt-Foxo1-GTPCH1 pathway. Peptides 2016; 86:95-101. [PMID: 27777063 DOI: 10.1016/j.peptides.2016.10.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 10/21/2016] [Accepted: 10/21/2016] [Indexed: 12/20/2022]
Abstract
Glucagon-like peptide-1 (GLP-1) and its analogues have a beneficial role in cardiovascular system. Here, we aimed to investigate whether liraglutide, a GLP-1 analogue, modulated angiogenesis impaired by palmitic acid (PA) in cultured human umbilical vein endothelial cells (HUVECs). Cells were incubated with liraglutide (3-100 nmol/L) in the presence of PA (0.5mmol/L), and endothelial tube formation was observed and quantified. The protein levels of signaling molecules were analyzed and the specific inhibitors were used to identify the signaling pathways through which liraglutide affected angiogenesis. Results showed that liraglutide ameliorated endothelial tube formation impaired by PA in HUVECs in a dose-dependent manner. Meanwhile, liraglutide increased the phosphorylation of Akt and forkhead box O1 (Foxo1), and upregulated the levels of guanosine 5'-triphosphate cyclohydrolase 1 (GTPCH1) and endothelial nitric oxide synthase (eNOS) in PA-impaired HUVECs. Notably, addition of the PI3K inhibitor LY294002, Foxo1 nuclear export inhibitor trifluoperazine dihydrochloride (TFP), GTPCH1 inhibitor 2,4-diamino-6-hydroxypyrimidine (DAHP) or NOS inhibitor N-nitro-l-arginine-methyl ester (L-NAME) eliminated the angiogenic effect of liraglutide. Moreover, either LY294002 or TFP abolished the liraglutide-induced upregulation of GTPCH1 and eNOS protein levels. In conclusion, liraglutide restores angiogenesis in PA-impaired HUVECs. The effect is mediated via upregulation of GTPCH1 and eNOS levels in a PI3K/Akt-Foxo1-dependent mechanism.
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Affiliation(s)
- Jing Ke
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China
| | - Rui Wei
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China
| | - Fei Yu
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China
| | - Jingjing Zhang
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China
| | - Tianpei Hong
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China.
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Dai YG, Gan P, Li WM, Yao Q, Li Y, Pei B, Cui J. [Effects of tetrahydrobiopterin on the angiogenesis in hepatocellular carcinoma]. Zhonghua Zhong Liu Za Zhi 2016; 38:806-811. [PMID: 27998437 DOI: 10.3760/cma.j.issn.0253-3766.2016.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the effect and mechanism of tetrahydrobiopterin (BH4) on the angiogenesis in hepatocellular carcinoma (HCC). Methods: BALB/c-nu mice were subcutaneously injected with HepG-2 cells and randomly divided into control and BH4 groups. The BH4 group and control group received 20 mg/kg BH4 or saline by intraperitoneal injection daily for two weeks, respectively. The level of BH4 was measured by high performance liquid chromatography (HPLC), the level of nitric oxide (NO) was measured by Griess test array, the transcriptional level of K-ras was measured by quantitative RT-PCR, and the protein expressions of guanosine triphosphate cyclohydrolase Ⅰ(GTPCH), endothelial nitric oxide synthase (eNOS), phospho-Akt and Akt were determined by Western blot. Results: BH4 level in the tumor tissues of BH4 group was (0.24±0.02) μg/ml, significantly higher than the (0.17±0.01) μg/ml in the control group (P<0.01). The level of NO in the tumor tissues of BH4 group was (51.44±2.90) mmol/L, significantly higher than the (24.77±0.54) mmol/L in the control group (P<0.01). The tumor volume of BH4 group was (191.05±8.70) mm3, significantly higher than the (103.10±5.03) mm3 in the control group (P<0.01). The expressions of CD34, K-ras, phospho-eNOS, phospho-Akt and GTPCH were significantly up-regulated in the tumor tissues of BH4 group when compared with those of the control group (P<0.01). Conclusions: BH4 recognized as an essential cofactor of eNOS can increase tumor-produced NO by activating the wild-type Ras-PI3K/Akt pathway, thus induces angiogenesis. This might provide a novel and promising way to control the progression of hepatocellular carcinoma through targeting BH4 synthesis pathway and inhibiting angiogenesis.
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Affiliation(s)
- Y G Dai
- Department of Abdominal Surgery, The Third Affiliated Hospital of Kunming Medical University, Kunming 650118, China
| | - P Gan
- Department of Abdominal Surgery, The Third Affiliated Hospital of Kunming Medical University, Kunming 650118, China
| | - W M Li
- Department of Gastrointestinal Surgery, The Second Affiliated Hospital of Kunming Medical University, Kunming 650101, China
| | - Q Yao
- Yunnan Cancer Research Institute, Kunming 650118, China
| | - Y Li
- Department of Abdominal Surgery, The Third Affiliated Hospital of Kunming Medical University, Kunming 650118, China
| | - B Pei
- Department of Abdominal Surgery, The Third Affiliated Hospital of Kunming Medical University, Kunming 650118, China
| | - J Cui
- Department of Pathology, The Second Affiliated Hospital of Kunming Medical University, Kunming 650101, China
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Ramírez Rivera NG, García-Salinas C, Aragão FJL, Díaz de la Garza RI. Metabolic engineering of folate and its precursors in Mexican common bean (Phaseolus vulgaris L.). Plant Biotechnol J 2016; 14:2021-32. [PMID: 26997331 PMCID: PMC5043471 DOI: 10.1111/pbi.12561] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 03/05/2016] [Accepted: 03/12/2016] [Indexed: 05/24/2023]
Abstract
Folate (vitamin B9) deficiency causes several health problems globally. However, folate biofortification of major staple crops is one alternative that can be used to improve vitamin intakes in populations at risk. We increased the folate levels in common bean by engineering the pteridine branch required for their biosynthesis. GTP cyclohydrolase I from Arabidopsis (AtGchI) was stably introduced into three common bean Pinto cultivars by particle bombardment. Seed-specific overexpression of AtGCHI caused significant increases of up to 150-fold in biosynthetic pteridines in the transformed lines. The pteridine boost enhanced folate levels in raw desiccated seeds by up to threefold (325 μg in a 100 g portion), which would represent 81% of the adult recommended daily allowance. Unexpectedly, the engineering also triggered a general increase in PABA levels, the other folate precursor. This was not observed in previous engineering studies and was probably caused by a feedforward mechanism that remains to be elucidated. Results from this work also show that common bean grains accumulate considerable amounts of oxidized pteridines that might represent products of folate degradation in desiccating seeds. Our study uncovers a probable different regulation of folate homoeostasis in these legume grains than that observed in other engineering works. Legumes are good sources of folates, and this work shows that they can be engineered to accumulate even greater amounts of folate that, when consumed, can improve folate status. Biofortification of common bean with folates and other micronutrients represents a promising strategy to improve the nutritional status of populations around the world.
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Affiliation(s)
- Naty G Ramírez Rivera
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Monterrey, Nuevo León, México
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Upadhyaya P, Tyagi K, Sarma S, Tamboli V, Sreelakshmi Y, Sharma R. Natural variation in folate levels among tomato (Solanum lycopersicum) accessions. Food Chem 2016; 217:610-619. [PMID: 27664678 DOI: 10.1016/j.foodchem.2016.09.031] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 06/02/2016] [Accepted: 09/05/2016] [Indexed: 11/17/2022]
Abstract
Folate content was estimated in tomato (Solanum lycopersicum) accessions using microbiological assay (MA) and by LC-MS. The MA revealed that in red-ripe fruits folate levels ranged from 4 to 60μg/100g fresh weight. The LC-MS estimation of red-ripe fruits detected three folate forms, 5-CH3-THF, 5-CHO-THF, 5,10-CH(+)THF and folate levels ranged from 14 to 46μg/100g fresh weight. In mature green and red ripe fruit, 5-CH3-THF was the most abundant folate form. Comparison of LC-MS with MA revealed that MA inaccurately estimates folate levels. The accumulation of folate forms and their distribution varied among accessions. The single nucleotide polymorphism was examined in the key genes of the folate pathway to understand its linkage with folate levels. Despite the significant variation in folate levels among tomato accessions, little polymorphism was found in folate biosynthesis genes. Our results indicate that variation in folate level is governed by a more complex regulation at cellular homeostasis level.
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Affiliation(s)
- Pallawi Upadhyaya
- Repository of Tomato Genomics Resources, Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.
| | - Kamal Tyagi
- Repository of Tomato Genomics Resources, Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.
| | - Supriya Sarma
- Repository of Tomato Genomics Resources, Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.
| | - Vajir Tamboli
- Repository of Tomato Genomics Resources, Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.
| | - Yellamaraju Sreelakshmi
- Repository of Tomato Genomics Resources, Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.
| | - Rameshwar Sharma
- Repository of Tomato Genomics Resources, Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.
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An H, Wei R, Ke J, Yang J, Liu Y, Wang X, Wang G, Hong T. Metformin attenuates fluctuating glucose-induced endothelial dysfunction through enhancing GTPCH1-mediated eNOS recoupling and inhibiting NADPH oxidase. J Diabetes Complications 2016; 30:1017-24. [PMID: 27217019 DOI: 10.1016/j.jdiacomp.2016.04.018] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 04/17/2016] [Accepted: 04/24/2016] [Indexed: 11/21/2022]
Abstract
AIMS The aim of this study was to investigate whether and how metformin ameliorated endothelial dysfunction induced by fluctuating glucose (FG) in human umbilical vein endothelial cells (HUVECs). METHODS HUVECs, which were exposed to FG to induce endothelial dysfunction, were incubated with nitric oxide synthase (NOS) inhibitor N-nitro-l-arginine-methyl ester (l-NAME), nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor apocynin, metformin and/or adenosine monophosphate-activated protein kinase (AMPK) inhibitor compound C. The oxidative stress and endothelial NOS (eNOS) coupling were evaluated. RESULTS FG induced endothelial dysfunction as indicated by increased reactive oxygen species (ROS) generation and decreased nitric oxide (NO) production. Although FG increased eNOS phosphorylation, uncoupled eNOS was evidenced by downregulated guanosine 5'-triphosphate cyclohydrolase 1 (GTPCH1) and tetrahydrobiopterin (BH4) levels. FG also upregulated the level of p47-phox, a subunit of NADPH oxidase. Similar to l-NAME and apocynin, metformin ameliorated the FG-induced endothelial dysfunction by decreasing ROS generation. Furthermore, metformin recoupled eNOS through upregulating GTPCH1 and BH4 levels, and attenuated the upregulation of p47-phox in FG-treated HUVECs. Addition of compound C abolished the above effects of metformin. CONCLUSION Metformin improves the FG-induced endothelial dysfunction in HUVECs. The protective effect of metformin may be mediated through activation of GTPCH1-mediated eNOS recoupling and inhibition of NADPH oxidase via an AMPK-dependent pathway.
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Affiliation(s)
- Huijie An
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China; Department of Endocrinology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Rui Wei
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China
| | - Jing Ke
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China
| | - Jin Yang
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China
| | - Ye Liu
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China
| | - Xian Wang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Science of Ministry of Education, Peking University Health Science Center, Beijing, China
| | - Guang Wang
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China; Department of Endocrinology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
| | - Tianpei Hong
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China.
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Wu HE, Baumgardt SL, Fang J, Paterson M, Liu Y, Du J, Shi Y, Qiao S, Bosnjak ZJ, Warltier DC, Kersten JR, Ge ZD. Cardiomyocyte GTP Cyclohydrolase 1 Protects the Heart Against Diabetic Cardiomyopathy. Sci Rep 2016; 6:27925. [PMID: 27295516 PMCID: PMC4904741 DOI: 10.1038/srep27925] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 05/26/2016] [Indexed: 02/06/2023] Open
Abstract
Diabetic cardiomyopathy increases the risk of heart failure and death. At present, there are no effective approaches to preventing its development in the clinic. Here we report that reduction of cardiac GTP cyclohydrolase 1 (GCH1) degradation by genetic and pharmacological approaches protects the heart against diabetic cardiomyopathy. Diabetic cardiomyopathy was induced in C57BL/6 wild-type mice and transgenic mice with cardiomyocyte-specific overexpression of GCH1 with streptozotocin, and control animals were given citrate buffer. We found that diabetes-induced degradation of cardiac GCH1 proteins contributed to adverse cardiac remodeling and dysfunction in C57BL/6 mice, concomitant with decreases in tetrahydrobiopterin, dimeric and phosphorylated neuronal nitric oxide synthase, sarcoplasmic reticulum Ca(2+) handling proteins, intracellular [Ca(2+)]i, and sarcoplasmic reticulum Ca(2+) content and increases in phosphorylated p-38 mitogen-activated protein kinase and superoxide production. Interestingly, GCH-1 overexpression abrogated these detrimental effects of diabetes. Furthermore, we found that MG 132, an inhibitor for 26S proteasome, preserved cardiac GCH1 proteins and ameliorated cardiac remodeling and dysfunction during diabetes. This study deepens our understanding of impaired cardiac function in diabetes, identifies GCH1 as a modulator of cardiac remodeling and function, and reveals a new therapeutic target for diabetic cardiomyopathy.
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Affiliation(s)
- Hsiang-En Wu
- Department of Anesthesiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
- National Institute on Drug Abuse, National Institutes of Health, 251 Bayview Boulevard, Baltimore, MA 21224, USA
| | - Shelley L. Baumgardt
- Department of Anesthesiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Juan Fang
- Department of Pediatrics, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Mark Paterson
- Department of Anesthesiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Yanan Liu
- Department of Medicine, Columbia University, 630 W. 168th Street, New York, NY 10032, USA
| | - Jianhai Du
- Department of Biochemistry, University of Washington, 1705 NE Pacific Street, Seattle, WA 98195, USA
| | - Yang Shi
- Aurora Research Institute, Aurora Health Care, 750 W. Virginia Street, Milwaukee, WI 53234, USA
| | - Shigang Qiao
- Department of Anesthesiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Zeljko J. Bosnjak
- Department of Anesthesiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - David C. Warltier
- Department of Anesthesiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Judy R. Kersten
- Department of Anesthesiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Zhi-Dong Ge
- Department of Anesthesiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
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Sethumadhavan S, Whitsett J, Bennett B, Ionova IA, Pieper GM, Vasquez-Vivar J. Increasing tetrahydrobiopterin in cardiomyocytes adversely affects cardiac redox state and mitochondrial function independently of changes in NO production. Free Radic Biol Med 2016; 93:1-11. [PMID: 26826575 PMCID: PMC5498285 DOI: 10.1016/j.freeradbiomed.2016.01.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 12/31/2015] [Accepted: 01/25/2016] [Indexed: 02/07/2023]
Abstract
Tetrahydrobiopterin (BH4) represents a potential strategy for the treatment of cardiac remodeling, fibrosis and/or diastolic dysfunction. The effects of oral treatment with BH4 (Sapropterin™ or Kuvan™) are however dose-limiting with high dose negating functional improvements. Cardiomyocyte-specific overexpression of GTP cyclohydrolase I (mGCH) increases BH4 several-fold in the heart. Using this model, we aimed to establish the cardiomyocyte-specific responses to high levels of BH4. Quantification of BH4 and BH2 in mGCH transgenic hearts showed age-based variations in BH4:BH2 ratios. Hearts of mice (<6 months) have lower BH4:BH2 ratios than hearts of older mice while both GTPCH activity and tissue ascorbate levels were higher in hearts of young than older mice. No evident changes in nitric oxide (NO) production assessed by nitrite and endogenous iron-nitrosyl complexes were detected in any of the age groups. Increased BH4 production in cardiomyocytes resulted in a significant loss of mitochondrial function. Diminished oxygen consumption and reserve capacity was verified in mitochondria isolated from hearts of 12-month old compared to 3-month old mice, even though at 12 months an improved BH4:BH2 ratio is established. Accumulation of 4-hydroxynonenal (4-HNE) and decreased glutathione levels were found in the mGCH hearts and isolated mitochondria. Taken together, our results indicate that the ratio of BH4:BH2 does not predict changes in neither NO levels nor cellular redox state in the heart. The BH4 oxidation essentially limits the capacity of cardiomyocytes to reduce oxidant stress. Cardiomyocyte with chronically high levels of BH4 show a significant decline in redox state and mitochondrial function.
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Affiliation(s)
- Savitha Sethumadhavan
- Department of Biophysics, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Jennifer Whitsett
- Department of Biophysics, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Brian Bennett
- Department of Biophysics, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA; Department of Physics, Marquette University, Milwaukee, 1250 W Wisconsin Ave, Milwaukee, WI 53233, USA
| | - Irina A Ionova
- Department of Surgery Medicine, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Galen M Pieper
- Department of Surgery Medicine, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Jeannette Vasquez-Vivar
- Department of Biophysics, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
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Hashimoto T, Sivakumaran V, Carnicer R, Zhu G, Hahn VS, Bedja D, Recalde A, Duglan D, Channon KM, Casadei B, Kass DA. Tetrahydrobiopterin Protects Against Hypertrophic Heart Disease Independent of Myocardial Nitric Oxide Synthase Coupling. J Am Heart Assoc 2016; 5:e003208. [PMID: 27001967 PMCID: PMC4943286 DOI: 10.1161/jaha.116.003208] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 02/11/2016] [Indexed: 01/09/2023]
Abstract
BACKGROUND Nitric oxide synthase uncoupling occurs under conditions of oxidative stress modifying the enzyme's function so it generates superoxide rather than nitric oxide. Nitric oxide synthase uncoupling occurs with chronic pressure overload, and both are ameliorated by exogenous tetrahydrobiopterin (BH4)-a cofactor required for normal nitric oxide synthase function-supporting a pathophysiological link. Genetically augmenting BH4 synthesis in endothelial cells fails to replicate this benefit, indicating that other cell types dominate the effects of exogenous BH4 administration. We tested whether the primary cellular target of BH4 is the cardiomyocyte or whether other novel mechanisms are invoked. METHODS AND RESULTS Mice with cardiomyocyte-specific overexpression of GTP cyclohydrolase 1 (mGCH1) and wild-type littermates underwent transverse aortic constriction. The mGCH1 mice had markedly increased myocardial BH4 and, unlike wild type, maintained nitric oxide synthase coupling after transverse aortic constriction; however, the transverse aortic constriction-induced abnormalities in cardiac morphology and function were similar in both groups. In contrast, exogenous BH4 supplementation improved transverse aortic constricted hearts in both groups, suppressed multiple inflammatory cytokines, and attenuated infiltration of inflammatory macrophages into the heart early after transverse aortic constriction. CONCLUSIONS BH4 protection against adverse remodeling in hypertrophic cardiac disease is not driven by its prevention of myocardial nitric oxide synthase uncoupling, as presumed previously. Instead, benefits from exogenous BH4 are mediated by a protective effect coupled to suppression of inflammatory pathways and myocardial macrophage infiltration.
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MESH Headings
- Animals
- Anti-Inflammatory Agents/pharmacology
- Biopterins/analogs & derivatives
- Biopterins/pharmacology
- Cardiovascular Agents/pharmacology
- Cytokines/metabolism
- Cytoprotection
- Disease Models, Animal
- GTP Cyclohydrolase/genetics
- GTP Cyclohydrolase/metabolism
- Humans
- Hypertrophy, Left Ventricular/enzymology
- Hypertrophy, Left Ventricular/pathology
- Hypertrophy, Left Ventricular/physiopathology
- Hypertrophy, Left Ventricular/prevention & control
- Inflammation Mediators/metabolism
- Macrophages/drug effects
- Macrophages/metabolism
- Mice, Transgenic
- Myocytes, Cardiac/drug effects
- Myocytes, Cardiac/enzymology
- Myocytes, Cardiac/pathology
- Nitric Oxide/metabolism
- Nitric Oxide Synthase/metabolism
- Oxidation-Reduction
- Signal Transduction
- Superoxides/metabolism
- Time Factors
- Ventricular Dysfunction, Left/enzymology
- Ventricular Dysfunction, Left/physiopathology
- Ventricular Dysfunction, Left/prevention & control
- Ventricular Function, Left/drug effects
- Ventricular Remodeling/drug effects
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Affiliation(s)
- Toru Hashimoto
- Division of Cardiology, Johns Hopkins Medical Institutions, Baltimore, MD
| | - Vidhya Sivakumaran
- Division of Cardiology, Johns Hopkins Medical Institutions, Baltimore, MD
| | | | - Guangshuo Zhu
- Division of Cardiology, Johns Hopkins Medical Institutions, Baltimore, MD
| | - Virginia S Hahn
- Division of Cardiology, Johns Hopkins Medical Institutions, Baltimore, MD
| | - Djahida Bedja
- Division of Cardiology, Johns Hopkins Medical Institutions, Baltimore, MD
| | - Alice Recalde
- Department of Cardiovascular Medicine, University of Oxford, UK
| | - Drew Duglan
- Department of Cardiovascular Medicine, University of Oxford, UK
| | - Keith M Channon
- Department of Cardiovascular Medicine, University of Oxford, UK
| | - Barbara Casadei
- Department of Cardiovascular Medicine, University of Oxford, UK
| | - David A Kass
- Division of Cardiology, Johns Hopkins Medical Institutions, Baltimore, MD
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Zhang HP, Zhao JH, Yu HX, Guo DX. Genistein ameliorated endothelial nitric oxidase synthase uncoupling by stimulating sirtuin-1 pathway in ox-LDL-injured HUVECs. Environ Toxicol Pharmacol 2016; 42:118-124. [PMID: 26829290 DOI: 10.1016/j.etap.2016.01.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 01/12/2016] [Accepted: 01/14/2016] [Indexed: 06/05/2023]
Abstract
Endothelial nitric oxidase synthase (eNOS) uncoupling plays a causal role in endothelial dysfunction in atherosclerosis. Genistein consumption has been associated with the prevention of atherosclerosis. However, the effect of genistein on eNOS uncoupling has not been reported. A model of oxidized low-density lipoprotein (ox-LDL)-induced injury on human umbilical vein endothelial cells (HUVECs) was established to evaluate the effect of genistein on eNOS uncoupling. We investigated the effect of genistein on NADPH oxidase-dependent superoxide production, NOX4 expression, BH4 synthesis and oxidation, the expression of GTP cyclohydrolase 1 (GCH1) and dihydrofolate reductase (DHFR). The results showed that genistein decreased superoxide production and NOX4 expression, enhanced the ratio of BH4/BH2, augmented the expressions of GCH1 and DHFR. Accompanied with genistein ameliorating eNOS uncoupling, genistein elevated the expression of sirtuin-1; furthermore, the effects of genistein on eNOS uncoupling were blunted with sirtuin-1 siRNA. The present study indicated that genistein ameliorated eNOS uncoupling was concerned with sirtuin-1 pathway in ox-LDL-injured HUVECs.
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Affiliation(s)
- Hua-ping Zhang
- Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, Shanxi 030001, PR China.
| | - Jia-hui Zhao
- Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, Shanxi 030001, PR China
| | - Hai-xia Yu
- Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, Shanxi 030001, PR China
| | - Dong-xing Guo
- Department of Pharmacology, School of Basic Medical Sciences, Shanxi Medical University, Taiyuan, Shanxi 030001, PR China
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Chen L, Zeng X, Kleibeuker E, Buffa F, Barberis A, Leek RD, Roxanis I, Zhang W, Worth A, Beech JS, Harris AL, Cai S. Paracrine effect of GTP cyclohydrolase and angiopoietin-1 interaction in stromal fibroblasts on tumor Tie2 activation and breast cancer growth. Oncotarget 2016; 7:9353-67. [PMID: 26814432 PMCID: PMC4891045 DOI: 10.18632/oncotarget.6981] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 12/26/2015] [Indexed: 12/19/2022] Open
Abstract
Cancer-associated fibroblasts (CAFs) play a key role in promoting tumor growth, acting through complex paracrine regulation. GTP cyclohydrolase (GTPCH) expression for tetrahydrobiopterin synthesis in tumor stroma is implicated in angiogenesis and tumor development. However, the clinical significance of GTPCH expression in breast cancer is still elusive and how GTPCH regulates stromal fibroblast and tumor cell communication remains unknown. We found that GTPCH was upregulated in breast CAFs and epithelia, and high GTPCH RNA was significantly correlated with larger high grade tumors and worse prognosis. In cocultures, GTPCH expressing fibroblasts stimulated breast cancer cell proliferation and motility, cancer cell Tie2 phosphorylation and consequent downstream pathway activation. GTPCH interacted with Ang-1 in stromal fibroblasts and enhanced Ang-1 expression and function, which in turn phosphorylated tumor Tie2 and induced cell proliferation. In coimplantation xenografts, GTPCH in fibroblasts enhanced tumor growth, upregulating Ang-1 and alpha-smooth muscle actin mainly in fibroblast-like cells. GTPCH inhibition resulted in the attenuation of tumor growth and angiogenesis. GTPCH/Ang-1 interaction in stromal fibroblasts and activation of Tie2 on breast tumor cells could play an important role in supporting breast cancer growth. GTPCH may be an important mechanism of paracrine tumor growth and hence a target for therapy in breast cancer.
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Affiliation(s)
- Liye Chen
- Molecular Oncology Laboratories, Department of Oncology, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Xin Zeng
- Molecular Oncology Laboratories, Department of Oncology, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
- Current address: Xiamen Institute for Diabetes Research, The First Affiliated Hospital of Xiamen University, Xiamen, China
| | - Esther Kleibeuker
- Molecular Oncology Laboratories, Department of Oncology, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Francesca Buffa
- Molecular Oncology Laboratories, Department of Oncology, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Alessandro Barberis
- Molecular Oncology Laboratories, Department of Oncology, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Russell D. Leek
- Molecular Oncology Laboratories, Department of Oncology, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Ioannis Roxanis
- Department of Cellular Pathology, Oxford University Hospitals and NIHR Biomedical Research Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Wei Zhang
- Nuffield Department of Obstetrics and Gynaecology, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Andrew Worth
- Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - John S. Beech
- Gray Institute for Radiation Oncology and Biology, Department of Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Adrian L. Harris
- Molecular Oncology Laboratories, Department of Oncology, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Shijie Cai
- Molecular Oncology Laboratories, Department of Oncology, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
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Santhanam AVR, d'Uscio LV, Katusic ZS. Characterization of cerebral microvasculature in transgenic mice with endothelium targeted over-expression of GTP-cyclohydrolase I. Brain Res 2015; 1625:198-205. [PMID: 26343845 PMCID: PMC4637228 DOI: 10.1016/j.brainres.2015.08.034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 08/14/2015] [Accepted: 08/26/2015] [Indexed: 01/05/2023]
Abstract
Tetrahydrobiopterin (BH4) is a critical determinant of nitric oxide (NO) production by nitric oxide synthase (NOS) in the vascular endothelium and its biosynthesis is regulated by the enzymatic activity of GTP-cyclohydrolase I (GTPCH I). The present study was designed to determine the effects of endothelium-targeted overexpression of GTPCH I (eGCH-Tg) on murine cerebral vascular function. Endothelium targeted over-expression of GTPCH I was associated with a significant increase in levels of BH4, as well as its oxidized product, 7,8-dihydrobiopterin (7,8-BH2) in cerebral microvessels. Importantly, ratio of BH4 to 7,8-BH2, indicative of BH4 available for eNOS activation, was significantly increased in eGCH-Tg mice. However, expression of endothelial NOS, levels of nitrate/nitrite--indicative of NO production--remained unchanged between cerebral microvessels of wild-type and eGCH-Tg mice. Furthermore, increased BH4 biosynthesis neither affected production of superoxide anion nor expression of antioxidant proteins. Moreover, endothelium-specific GTPCH I overexpression did not alter intracellular levels of cGMP, reflective of NO signaling in cerebral microvessels. The obtained results suggest that, despite a significant increase in BH4 bioavailability, generation of endothelial NO in cerebral microvessels remained unchanged in eGCH-Tg mice. We conclude that under physiological conditions the levels of BH4 in the cerebral microvessels are optimal for activation of endothelial NOS and NO/cGMP signaling.
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Affiliation(s)
- Anantha Vijay R Santhanam
- Departments of Anesthesiology and Molecular Pharmacology & Experimental Therapeutics, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA
| | - Livius V d'Uscio
- Departments of Anesthesiology and Molecular Pharmacology & Experimental Therapeutics, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA
| | - Zvonimir S Katusic
- Departments of Anesthesiology and Molecular Pharmacology & Experimental Therapeutics, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA.
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Hussein D, Starr A, Heikal L, McNeill E, Channon KM, Brown PR, Sutton BJ, McDonnell JM, Nandi M. Validating the GTP-cyclohydrolase 1-feedback regulatory complex as a therapeutic target using biophysical and in vivo approaches. Br J Pharmacol 2015; 172:4146-57. [PMID: 26014146 PMCID: PMC4543619 DOI: 10.1111/bph.13202] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 05/12/2015] [Accepted: 05/13/2015] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND AND PURPOSE 6R-L-erythro-5,6,7,8-tetrahydrobiopterin (BH4 ) is an essential cofactor for nitric oxide biosynthesis. Substantial clinical evidence indicates that intravenous BH4 restores vascular function in patients. Unfortunately, oral BH4 has limited efficacy. Therefore, orally bioavailable pharmacological activators of endogenous BH4 biosynthesis hold significant therapeutic potential. GTP-cyclohydrolase 1 (GCH1), the rate limiting enzyme in BH4 synthesis, forms a protein complex with GCH1 feedback regulatory protein (GFRP). This complex is subject to allosteric feed-forward activation by L-phenylalanine (L-phe). We investigated the effects of L-phe on the biophysical interactions of GCH1 and GFRP and its potential to alter BH4 levels in vivo. EXPERIMENTAL APPROACH Detailed characterization of GCH1-GFRP protein-protein interactions were performed using surface plasmon resonance (SPR) with or without L-phe. Effects on systemic and vascular BH4 biosynthesis in vivo were investigated following L-phe treatment (100 mg·kg(-1) , p.o.). KEY RESULTS GCH1 and GFRP proteins interacted in the absence of known ligands or substrate but the presence of L-phe doubled maximal binding and enhanced binding affinity eightfold. Furthermore, the complex displayed very slow association and dissociation rates. In vivo, L-phe challenge induced a sustained elevation of aortic BH4 , an effect absent in GCH1(fl/fl)-Tie2Cre mice. CONCLUSIONS AND IMPLICATIONS Biophysical data indicate that GCH1 and GFRP are constitutively bound. In vivo, data demonstrated that L-phe elevated vascular BH4 in an endothelial GCH1 dependent manner. Pharmacological agents which mimic the allosteric effects of L-phe on the GCH1-GFRP complex have the potential to elevate endothelial BH4 biosynthesis for numerous cardiovascular disorders.
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Affiliation(s)
- D Hussein
- Institute of Pharmaceutical Science, Faculty of Life Sciences & Medicine, King's College LondonLondon, UK
| | - A Starr
- Institute of Pharmaceutical Science, Faculty of Life Sciences & Medicine, King's College LondonLondon, UK
| | - L Heikal
- Institute of Pharmaceutical Science, Faculty of Life Sciences & Medicine, King's College LondonLondon, UK
| | - E McNeill
- British Heart Foundation Centre of Research Excellence, Division of Cardiovascular Medicine, University of Oxford, John Radcliffe HospitalOxford, UK
| | - K M Channon
- British Heart Foundation Centre of Research Excellence, Division of Cardiovascular Medicine, University of Oxford, John Radcliffe HospitalOxford, UK
| | - P R Brown
- The Randall Division of Cell and Molecular Biophysics, Faculty of Life Sciences & Medicine, King's College LondonLondon, UK
| | - B J Sutton
- The Randall Division of Cell and Molecular Biophysics, Faculty of Life Sciences & Medicine, King's College LondonLondon, UK
| | - J M McDonnell
- The Randall Division of Cell and Molecular Biophysics, Faculty of Life Sciences & Medicine, King's College LondonLondon, UK
| | - M Nandi
- Institute of Pharmaceutical Science, Faculty of Life Sciences & Medicine, King's College LondonLondon, UK
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Abstract
Coordinated serotonin (5-HT) synthesis and reuptake depends on coexpression of Tph2, Aadc (Ddc), and Sert (Slc6a4) in brain 5-HT neurons. However, other gene products play critical roles in brain 5-HT synthesis and transport. For example, 5-HT synthesis depends on coexpression of genes encoding the enzymatic machinery necessary for the production and regeneration of tetrahydrobiopterin (BH4). In addition, the organic cation transporter 3 (Oct3, Slc22a3) functions as a low affinity, high capacity 5-HT reuptake protein in 5-HT neurons. The regulatory strategies controlling BH4 and Oct3 gene expression in 5-HT neurons have not been investigated. Our previous studies showed that Pet-1 is a critical transcription factor in a regulatory program that controls coexpression of Tph2, Aadc, and Sert in 5-HT neurons. Here, we investigate whether a common regulatory program determines global 5-HT synthesis and reuptake through coordinate transcriptional control. We show with comparative microarray profiling of flow sorted YFP(+) Pet-1(-/-) and wild type 5-HT neurons that Pet-1 regulates BH4 pathway genes, Gch1, Gchfr, and Qdpr. Thus, Pet-1 coordinates expression of all rate-limiting enzymatic (Tph2, Gch1) and post-translational regulatory (Gchfr) steps that determine the level of mammalian brain 5-HT synthesis. Moreover, Pet-1 globally controls acquisition of 5-HT reuptake in dorsal raphe 5-HT neurons by coordinating expression of Slc6a4 and Slc22a3. In situ hybridizations revealed that virtually all 5-HT neurons in the dorsal raphe depend on Pet-1 for Slc22a3 expression; similar results were obtained for Htr1a. Therefore, few if any 5-HT neurons in the dorsal raphe are resistant to loss of Pet-1 for their full neuron-type identity.
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Affiliation(s)
| | | | - Mia Yeager
- Department of Neurosciences, Case Western Reserve University Cleveland, Ohio, 44106, United States
| | - Evan Deneris
- Department of Neurosciences, Case Western Reserve University Cleveland, Ohio, 44106, United States
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