1
|
Zhai Y, Chavez JA, D'Aquino KE, Meng R, Nawrocki AR, Pocai A, Wang L, Ma LJ. Kynurenine 3-monooxygenase limits de novo NAD + synthesis through dietary tryptophan in renal proximal tubule epithelial cell models. Am J Physiol Cell Physiol 2024; 326:C1423-C1436. [PMID: 38497113 DOI: 10.1152/ajpcell.00445.2023] [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] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 02/15/2024] [Accepted: 03/13/2024] [Indexed: 03/19/2024]
Abstract
Nicotinamide adenine dinucleotide (NAD+) is a pivotal coenzyme, essential for cellular reactions, metabolism, and mitochondrial function. Depletion of kidney NAD+ levels and reduced de novo NAD+ synthesis through the tryptophan-kynurenine pathway are linked to acute kidney injury (AKI), whereas augmenting NAD+ shows promise in reducing AKI. We investigated de novo NAD+ biosynthesis using in vitro, ex vivo, and in vivo models to understand its role in AKI. Two-dimensional (2-D) cultures of human primary renal proximal tubule epithelial cells (RPTECs) and HK-2 cells showed limited de novo NAD+ synthesis, likely due to low pathway enzyme gene expression. Using three-dimensional (3-D) spheroid culture model improved the expression of tubular-specific markers and enzymes involved in de novo NAD+ synthesis. However, de novo NAD+ synthesis remained elusive in the 3-D spheroid culture, regardless of injury conditions. Further investigation revealed that 3-D cultured cells could not metabolize tryptophan (Trp) beyond kynurenine (KYN). Intriguingly, supplementation of 3-hydroxyanthranilic acid into RPTEC spheroids was readily incorporated into NAD+. In a human precision-cut kidney slice (PCKS) ex vivo model, de novo NAD+ synthesis was limited due to substantially downregulated kynurenine 3-monooxygenase (KMO), which is responsible for KYN to 3-hydroxykynurenine conversion. KMO overexpression in RPTEC 3-D spheroids successfully reinstated de novo NAD+ synthesis from Trp. In addition, in vivo study demonstrated that de novo NAD+ synthesis is intact in the kidney of the healthy adult mice. Our findings highlight disrupted tryptophan-kynurenine NAD+ synthesis in in vitro cellular models and an ex vivo kidney model, primarily attributed to KMO downregulation.NEW & NOTEWORTHY Nicotinamide adenine dinucleotide (NAD+) is essential in regulating mitochondrial function. Reduced NAD+ synthesis through the de novo pathway is associated with acute kidney injury (AKI). Our study reveals a disruption in de novo NAD+ synthesis in proximal tubular models, but not in vivo, attributed to downregulation of enzyme kynurenine 3-monooxygenase (KMO). These findings highlight a crucial role of KMO in governing de novo NAD+ biosynthesis within the kidney, shedding light on potential AKI interventions.
Collapse
Affiliation(s)
- Yougang Zhai
- CVMR-PH Discovery, Johnson & Johnson Innovative Medicine Research & Development, Spring House, Pennsylvania, United States
| | - Jose A Chavez
- CVMR-PH Discovery, Johnson & Johnson Innovative Medicine Research & Development, Spring House, Pennsylvania, United States
| | - Katharine E D'Aquino
- CVMR-PH Discovery, Johnson & Johnson Innovative Medicine Research & Development, Spring House, Pennsylvania, United States
| | - Rong Meng
- CVMR-PH Discovery, Johnson & Johnson Innovative Medicine Research & Development, Spring House, Pennsylvania, United States
| | - Andrea R Nawrocki
- CVMR-PH Discovery, Johnson & Johnson Innovative Medicine Research & Development, Spring House, Pennsylvania, United States
| | - Alessandro Pocai
- CVMR-PH Discovery, Johnson & Johnson Innovative Medicine Research & Development, Spring House, Pennsylvania, United States
| | - Lifeng Wang
- CVMR-PH Discovery, Johnson & Johnson Innovative Medicine Research & Development, Spring House, Pennsylvania, United States
| | - Li-Jun Ma
- CVMR-PH Discovery, Johnson & Johnson Innovative Medicine Research & Development, Spring House, Pennsylvania, United States
| |
Collapse
|
2
|
Shi Y, Luo S, Zhai J, Chen Y. A novel causative role of imbalanced kynurenine pathway in ulcerative colitis: Upregulation of KMO and KYNU promotes intestinal inflammation. Biochim Biophys Acta Mol Basis Dis 2024; 1870:166929. [PMID: 37918679 DOI: 10.1016/j.bbadis.2023.166929] [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: 07/11/2023] [Revised: 10/14/2023] [Accepted: 10/25/2023] [Indexed: 11/04/2023]
Abstract
The kynurenine pathway (KP) is the principal metabolic route for the essential amino acid tryptophan (TRP). Recent advances have highlighted a pivotal role for several KP metabolites in inflammatory diseases, including ulcerative colitis (UC). However, the alterations of KP enzymes and their functional impact in UC remain poorly defined. Here, we focused on kynurenine 3-monooxygenase (KMO) and kynureninase (KYNU), which serve as critical branching enzymes in the KP. We observed that dextran sodium sulfate (DSS)-induced colitis mice exhibited disturbed TRP metabolism along with KMO and KYNU upregulated. In patients with active UC, both the expression of KMO and KYNU were positively correlated with inflammatory factors TNF-α and IL-1β. Pharmacological blockade of KMO or genetic silencing of KYNU suppressed IL-1β-triggered proinflammatory cytokines expression in intestinal epithelial cells. Furthermore, blockage of KMO by selective inhibitor Ro 61-8048 alleviated the symptoms of DSS-induced colitis in mice, accompanied by an expanded NAD+ pool and redox balance restoration. The protective role of Ro 61-8048 may be partly due to its effect on KP regulation, particularly in enhancing kynurenic acid production. In summary, our study provides new evidence for the proinflammatory property of KMO and KYNU in intestinal inflammation, hinting at a promising therapeutic approach in UC through targeting these enzymes.
Collapse
Affiliation(s)
- Yingying Shi
- Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition, Shanghai, China
| | - Shangjian Luo
- Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition, Shanghai, China
| | - Jinyang Zhai
- Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition, Shanghai, China
| | - Yingwei Chen
- Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| |
Collapse
|
3
|
Sordillo LA, Sordillo PP. Suppression of Kynurenine 3-Monooxygenase as a Treatment for Triple-negative Breast Carcinoma. Anticancer Res 2023; 43:5275-5282. [PMID: 38030171 DOI: 10.21873/anticanres.16731] [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: 10/16/2023] [Revised: 11/04/2023] [Accepted: 11/07/2023] [Indexed: 12/01/2023]
Abstract
Kynurenine 3-monooxygenase (KMO), a key enzyme within the kynurenine (KYN) pathway of tryptophan (TRY) metabolism, enables the excess production of toxic metabolites (such as 3-hydroxykynurenine, xanthurenic acid, 3-hydroxyanthranilic acid and quinolinic acid), and modulates the balance between these toxic molecules and the protective metabolite, kynurenic acid (KYNA). Despite its importance, KMO suppression as a treatment for cancer has not been fully explored. Instead, researchers have focused on prevention of KYN pathway activity by inhibition of enzymes indoleamine 2,3-dioxygenase (IDO1 and IDO2) or tryptophan 2,3-dioxygenase (TDO, also known as TDO2). However, studies using IDO/TDO inhibitors against cancer have not yet shown that this type of treatment can be successful. We argue that KMO suppression can be an effective strategy for treatment of cancer by 1) decreasing toxic metabolites within the KYN pathway and 2) increasing levels of KYNA, which has important protective and anticancer properties. This strategy may be beneficial in the treatment of aggressive breast cancer, particularly in patients with triple-negative breast cancer. A major challenge to this strategy, when searching for an effective treatment for tumors, especially tumors like breast carcinoma that often metastasize to the brain, is finding KMO inhibitors that adequately cross the blood-brain barrier.
Collapse
|
4
|
Jakkampudi A, Sarkar P, Unnisa M, Patil A, Koutarapu C, Jaggaiahgari S, Naik P, Sarkar S, Prasanna A, Chintaluri S, Reddy DN, Beedu SR, Talukdar R. Kynurenine pathway alteration in acute pancreatitis and its role as a biomarker of infected necrosis. Pancreatology 2023; 23:589-600. [PMID: 37438173 DOI: 10.1016/j.pan.2023.07.003] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 06/18/2023] [Accepted: 07/04/2023] [Indexed: 07/14/2023]
Abstract
INTRODUCTION Infected pancreatic necrosis (IPN) is a major cause of mortality in acute pancreatitis (AP). Currently, no specific strategies are available to predict the development of IPN. Earlier we reported that persistent down-regulation of HLA-DR increases risk of developing IPN. Altered kynurenine pathway (KP) metabolites showed poor prognosis in sepsis. Here we evaluated the role of HLA-DR and KP in IPN. METHODS Patients with ANP and healthy controls were enrolled. Demographic and clinical parameters were recorded. Circulating interleukin (IL)-8, 6, 1β, 10, Tumor necrosis factor-α were quantified using flowcytometry. Plasma procalcitonin, endotoxin, and KP (tryptophan, kynurenine) concentrations were estimated using ELISA. qRT-PCR was conducted to evaluate mRNA expression of HLA-DR, IL-10, Toll like receptor-4 (TLR-4), and kynurenine-3-monooxygenase (KMO) genes on peripheral blood mononuclear cells. Plasma metabolites were quantified using gas chromatography mass spectrometry (GC-MS/MS). Standard statistical methods were used to compare study groups. Metaboanalyst was used to analyse/visualize the metabolomics data. RESULTS We recruited 56 patients in Cohort-1 (IPN:26,Non-IPN:30), 78 in Cohort-2 (IPN:57,Non-IPN:21), 26 healthy controls. Increased cytokines, endotoxin, and procalcitonin were observed in patients with IPN compared to Non-IPN. HLA-DR and KMO gene expressions were significantly down-regulated in IPN groups, showed positive correlation with one another but negatively correlated with IL-6 and endotoxin concentrations. Increased IDO and decreased plasma tryptophan were observed in IPN patients. Metabolome analysis showed significant reduction in several essential amino acids including tryptophan in IPN patients. Tryptophan, at a concentration of 9 mg/ml showed an AUC of 91.9 (95%CI 86.5-97.4) in discriminating IPN. CONCLUSION HLA-DR downregulation and KP alteration are related to IPN. The KP metabolite plasma tryptophan can act as a potential biomarker for IPN.
Collapse
Affiliation(s)
- Aparna Jakkampudi
- Wellcome DBT India Alliance Labs., Institute of Translational Research, Asian Healthcare Foundation, Hyderabad, India
| | - Priyanka Sarkar
- Wellcome DBT India Alliance Labs., Institute of Translational Research, Asian Healthcare Foundation, Hyderabad, India
| | - Misbah Unnisa
- Pancreas Clinic, Dept. of Gastroenterology, Asian Institute of Gastroenterology, Hyderabad, India
| | - Aashish Patil
- Pancreas Clinic, Dept. of Gastroenterology, Asian Institute of Gastroenterology, Hyderabad, India
| | - Chandrakanth Koutarapu
- Pancreas Clinic, Dept. of Gastroenterology, Asian Institute of Gastroenterology, Hyderabad, India
| | - Shashidhar Jaggaiahgari
- Wellcome DBT India Alliance Labs., Institute of Translational Research, Asian Healthcare Foundation, Hyderabad, India
| | - Pragathi Naik
- Dept. of Transfusion Medicine, Asian Institute of Gastroenterology, Hyderabad, India
| | - Subhaleena Sarkar
- Wellcome DBT India Alliance Labs., Institute of Translational Research, Asian Healthcare Foundation, Hyderabad, India
| | - Ambika Prasanna
- Wellcome DBT India Alliance Labs., Institute of Translational Research, Asian Healthcare Foundation, Hyderabad, India
| | - Sreelekha Chintaluri
- Wellcome DBT India Alliance Labs., Institute of Translational Research, Asian Healthcare Foundation, Hyderabad, India
| | - D Nageshwar Reddy
- Pancreas Clinic, Dept. of Gastroenterology, Asian Institute of Gastroenterology, Hyderabad, India
| | | | - Rupjyoti Talukdar
- Wellcome DBT India Alliance Labs., Institute of Translational Research, Asian Healthcare Foundation, Hyderabad, India; Pancreas Clinic, Dept. of Gastroenterology, Asian Institute of Gastroenterology, Hyderabad, India.
| |
Collapse
|
5
|
Bai L, Han X, Kee HJ, He X, Kim SH, Jeon MJ, Zhou H, Jeong SM, Kee SJ, Jeong MH. Protocatechuic acid prevents isoproterenol-induced heart failure in mice by downregulating kynurenine-3-monooxygenase. J Cell Mol Med 2023; 27:2290-2307. [PMID: 37482908 PMCID: PMC10424289 DOI: 10.1111/jcmm.17869] [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: 01/12/2023] [Revised: 06/12/2023] [Accepted: 07/12/2023] [Indexed: 07/25/2023] Open
Abstract
Protocatechuic acid (3,4-dihydroxybenzoic acid) prevents oxidative stress, inflammation and cardiac hypertrophy. This study aimed to investigate the therapeutic effects of protocatechuic acid in an isoproterenol-induced heart failure mouse model and to identify the underlying mechanisms. To establish the heart failure model, C57BL/6NTac mice were given high-dose isoproterenol (80 mg/kg body weight) for 14 days. Echocardiography revealed that protocatechuic acid reversed the isoproterenol-induced downregulation of fractional shortening and ejection fraction. Protocatechuic acid attenuated cardiac hypertrophy as evidenced by the decreased heart-weight-to-body-weight ratio and the expression of Nppb. RNA sequencing analysis identified kynurenine-3-monooxygenase (Kmo) as a potential target of protocatechuic acid. Protocatechuic acid treatment or transfection with short-interfering RNA against Kmo ameliorated transforming growth factor β1-induced upregulation of Kmo, Col1a1, Col1a2 and Fn1 in vivo or in neonatal rat cardiac fibroblasts. Kmo knockdown attenuated the isoproterenol-induced increase in cardiomyocyte size, as well as Nppb and Col1a1 expression in H9c2 cells or primary neonatal rat cardiomyocytes. Moreover, protocatechuic acid attenuated Kmo overexpression-induced increases in Nppb mRNA levels. Protocatechuic acid or Kmo knockdown decreased isoproterenol-induced ROS generation in vivo and in vitro. Thus, protocatechuic acid prevents heart failure by downregulating Kmo. Therefore, protocatechuic acid and Kmo constitute a potential novel therapeutic agent and target, respectively, against heart failure.
Collapse
Affiliation(s)
- Liyan Bai
- Heart Research Center of Chonnam National University Hospital, Gwangju, Republic of Korea
- Hypertension Heart Failure Research Center, Chonnam National University Hospital, Gwangju, Republic of Korea
- Emergency Critical Center, Beijing Anzhen Hospital, Capital Medical University, Beijing, People's Republic of China
| | - Xiongyi Han
- Heart Research Center of Chonnam National University Hospital, Gwangju, Republic of Korea
- Hypertension Heart Failure Research Center, Chonnam National University Hospital, Gwangju, Republic of Korea
- Aerospace Center Hospital, Peking University Aerospace School of Clinical Medicine, Beijing, People's Republic of China
| | - Hae Jin Kee
- Heart Research Center of Chonnam National University Hospital, Gwangju, Republic of Korea
- Hypertension Heart Failure Research Center, Chonnam National University Hospital, Gwangju, Republic of Korea
| | - Xiaonan He
- Emergency Critical Center, Beijing Anzhen Hospital, Capital Medical University, Beijing, People's Republic of China
| | - Seong Hoon Kim
- Department of Parasitology and Tropical Medicine, Chonnam National University Medical School, Hwasun, Republic of Korea
| | - Mi Jin Jeon
- Heart Research Center of Chonnam National University Hospital, Gwangju, Republic of Korea
- Hypertension Heart Failure Research Center, Chonnam National University Hospital, Gwangju, Republic of Korea
| | - Hongyan Zhou
- Heart Research Center of Chonnam National University Hospital, Gwangju, Republic of Korea
- Hypertension Heart Failure Research Center, Chonnam National University Hospital, Gwangju, Republic of Korea
| | - Seong Min Jeong
- Heart Research Center of Chonnam National University Hospital, Gwangju, Republic of Korea
- Hypertension Heart Failure Research Center, Chonnam National University Hospital, Gwangju, Republic of Korea
| | - Seung-Jung Kee
- Department of Laboratory Medicine, Chonnam National University Medical School and Hospital, Gwangju, Republic of Korea
| | - Myung Ho Jeong
- Heart Research Center of Chonnam National University Hospital, Gwangju, Republic of Korea
- Hypertension Heart Failure Research Center, Chonnam National University Hospital, Gwangju, Republic of Korea
- Department of Cardiology, Chonnam National University Medical School, Gwangju, Republic of Korea
| |
Collapse
|
6
|
Cai Y, Bai F, Chen J, Li W, Bao H, Zhang Y, Chen J, Shen W. Kynurenine 3-Monooxygenase Gene SsCI51640 Is Required for Sporisorium scitamineum Mating/Filamentation by Regulating cAMP Pathway and Improving Sporidia Environmental Adaptability. Phytopathology 2023; 113:484-496. [PMID: 36173285 DOI: 10.1094/phyto-05-22-0153-r] [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] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Sugarcane smut is a serious disease caused by Sporisorium scitamineum, which causes significant losses to the sugar industry. It is critical to reveal the molecular pathogenic mechanism of S. scitamineum to explore a new control strategy for sugarcane smut. On the basis of transcriptome sequencing data of two S. scitamineum strains with different pathogenicity, we identified the gene, SsCI51640, which was predicted to encode kynurenine 3-monooxygenase. In this study, we obtained knockout mutants and complementary mutants of this gene and identified gene function. The results showed that the sporidial growth rate and acid production ability of knockout mutants were significantly higher and stronger than those of the wild-type and complementary mutants. The growth of knockout mutants under abiotic stress (osmotic stress and cell wall stress) was significantly inhibited. In addition, the sexual mating ability and pathogenicity of knockout mutants were significantly reduced, while this phenomenon could be restored by adding exogenous cyclic adenosine monophosphate (cAMP). It is thus speculated that the SsCI51640 gene may regulate sexual mating and pathogenicity of S. scitamineum by the cAMP signaling pathway. Moreover, the SsCI51640 gene enhanced the sporidial environmental adaptability, which promoted sexual mating and development of pathogenicity. This study provides a theoretical basis for the molecular pathogenesis of S. scitamineum.
Collapse
Affiliation(s)
- Yichang Cai
- College of Agriculture, South China Agricultural University, Guangzhou 510642, P.R. China
- Sugarcane Research Laboratory, South China Agricultural University, Guangzhou 510642, P.R. China
| | - Feng Bai
- College of Agriculture, South China Agricultural University, Guangzhou 510642, P.R. China
| | - Jiaoyun Chen
- College of Agriculture, South China Agricultural University, Guangzhou 510642, P.R. China
- Sugarcane Research Laboratory, South China Agricultural University, Guangzhou 510642, P.R. China
| | - Wenjia Li
- College of Agriculture, South China Agricultural University, Guangzhou 510642, P.R. China
- Sugarcane Research Laboratory, South China Agricultural University, Guangzhou 510642, P.R. China
| | - Han Bao
- College of Agriculture, South China Agricultural University, Guangzhou 510642, P.R. China
- Sugarcane Research Laboratory, South China Agricultural University, Guangzhou 510642, P.R. China
| | - Yi Zhang
- College of Agriculture, South China Agricultural University, Guangzhou 510642, P.R. China
- Sugarcane Research Laboratory, South China Agricultural University, Guangzhou 510642, P.R. China
| | - Jianwen Chen
- College of Agriculture, South China Agricultural University, Guangzhou 510642, P.R. China
- Sugarcane Research Laboratory, South China Agricultural University, Guangzhou 510642, P.R. China
| | - Wankuan Shen
- College of Agriculture, South China Agricultural University, Guangzhou 510642, P.R. China
- Sugarcane Research Laboratory, South China Agricultural University, Guangzhou 510642, P.R. China
- Scientific Observing and Experimental Station of Crop Cultivation in South China, Ministry of Agriculture and Rural Areas, Guangzhou 510642, P.R. China
| |
Collapse
|
7
|
Zhao J, Chen J, Wang C, Liu Y, Li M, Li Y, Li R, Han Z, Wang J, Chen L, Shu Y, Cheng G, Sun C. Kynurenine-3-monooxygenase (KMO) broadly inhibits viral infections via triggering NMDAR/Ca2+ influx and CaMKII/ IRF3-mediated IFN-β production. PLoS Pathog 2022; 18:e1010366. [PMID: 35235615 PMCID: PMC8920235 DOI: 10.1371/journal.ppat.1010366] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [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: 10/26/2021] [Revised: 03/14/2022] [Accepted: 02/14/2022] [Indexed: 12/24/2022] Open
Abstract
Tryptophan (Trp) metabolism through the kynurenine pathway (KP) is well known to play a critical function in cancer, autoimmune and neurodegenerative diseases. However, its role in host-pathogen interactions has not been characterized yet. Herein, we identified that kynurenine-3-monooxygenase (KMO), a key rate-limiting enzyme in the KP, and quinolinic acid (QUIN), a key enzymatic product of KMO enzyme, exerted a novel antiviral function against a broad range of viruses. Mechanistically, QUIN induced the production of type I interferon (IFN-I) via activating the N-methyl-d-aspartate receptor (NMDAR) and Ca2+ influx to activate Calcium/calmodulin-dependent protein kinase II (CaMKII)/interferon regulatory factor 3 (IRF3). Importantly, QUIN treatment effectively inhibited viral infections and alleviated disease progression in mice. Furthermore, kmo-/- mice were vulnerable to pathogenic viral challenge with severe clinical symptoms. Collectively, our results demonstrated that KMO and its enzymatic product QUIN were potential therapeutics against emerging pathogenic viruses. The outbreaks of emerging infectious diseases have become a severe challenge worldwide, and therefore it is a public health priority to explore novel broad-spectrum antiviral agents with various mechanisms. This study reported that kynurenine-3-monooxygenase (KMO), a key rate-limiting enzyme during tryptophan metabolism, showed promise as a novel broad-spectrum antiviral factor against emerging pathogenic viruses. We further found that quinolinic acid (QUIN), an enzymatic product of KMO, could also act as a novel broad-spectrum antiviral agent. We then systematically studied the underlying mechanisms and broadly antiviral function of KMO and QUIN in vitro and in vivo. Our data highlight the importance of exploring novel antiviral targets from the key enzymes and their metabolites in tryptophan metabolism.
Collapse
Affiliation(s)
- Jin Zhao
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, China
- Key Laboratory of Tropical Disease Control (Sun Yat-sen university), Ministry of Education, Guangzhou, China
| | - Jiaoshan Chen
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, China
- Key Laboratory of Tropical Disease Control (Sun Yat-sen university), Ministry of Education, Guangzhou, China
| | - Congcong Wang
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, China
- Key Laboratory of Tropical Disease Control (Sun Yat-sen university), Ministry of Education, Guangzhou, China
| | - Yajie Liu
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, China
- Key Laboratory of Tropical Disease Control (Sun Yat-sen university), Ministry of Education, Guangzhou, China
| | - Minchao Li
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, China
- Key Laboratory of Tropical Disease Control (Sun Yat-sen university), Ministry of Education, Guangzhou, China
| | - Yanjun Li
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, China
- Key Laboratory of Tropical Disease Control (Sun Yat-sen university), Ministry of Education, Guangzhou, China
| | - Ruiting Li
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, China
- Key Laboratory of Tropical Disease Control (Sun Yat-sen university), Ministry of Education, Guangzhou, China
| | - Zirong Han
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, China
- Key Laboratory of Tropical Disease Control (Sun Yat-sen university), Ministry of Education, Guangzhou, China
| | - Junjian Wang
- Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Ling Chen
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health (GIBH), Chinese Academy of Sciences, Guangzhou, China
| | - Yuelong Shu
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, China
- Key Laboratory of Tropical Disease Control (Sun Yat-sen university), Ministry of Education, Guangzhou, China
| | - Genhong Cheng
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, California, United States of America
- * E-mail: (GC); (CS)
| | - Caijun Sun
- School of Public Health (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, China
- Key Laboratory of Tropical Disease Control (Sun Yat-sen university), Ministry of Education, Guangzhou, China
- * E-mail: (GC); (CS)
| |
Collapse
|
8
|
Lassiter R, Merchen TD, Fang X, Wang Y. Protective Role of Kynurenine 3-Monooxygenase in Allograft Rejection and Tubular Injury in Kidney Transplantation. Front Immunol 2021; 12:671025. [PMID: 34305900 PMCID: PMC8293746 DOI: 10.3389/fimmu.2021.671025] [Citation(s) in RCA: 2] [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: 02/22/2021] [Accepted: 06/11/2021] [Indexed: 11/13/2022] Open
Abstract
Renal tubular epithelial cells (TECs) are the primary targets of ischemia-reperfusion injury (IRI) and rejection by the recipient's immune response in kidney transplantation (KTx). However, the molecular mechanism of rejection and IRI remains to be identified. Our previous study demonstrated that kynurenine 3-monooxygenase (KMO) and kynureninase were reduced in ischemia-reperfusion procedure and further decreased in rejection allografts among mismatched pig KTx. Herein, we reveal that TEC injury in acutely rejection allografts is associated with alterations of Bcl2 family proteins, reduction of tight junction protein 1 (TJP1), and TEC-specific KMO. Three cytokines, IFN γ , TNFα, and IL1β, reported in our previous investigation were identified as triggers of TEC injury by altering the expression of Bcl2, BID, and TJP1. Allograft rejection and TEC injury were always associated with a dramatic reduction of KMO. 3HK and 3HAA, as direct and downstream products of KMO, effectively protected TEC from injury via increasing expression of Bcl-xL and TJP1. Both 3HK and 3HAA further prevented allograft rejection by inhibiting T cell proliferation and up-regulating aryl hydrocarbon receptor expression. Pig KTx with the administration of DNA nanoparticles (DNP) that induce expression of indoleamine 2,3-dioxygenase (IDO) and KMO to increase 3HK/3HAA showed an improvement of allograft rejection as well as murine skin transplant in IDO knockout mice with the injection of 3HK indicated a dramatic reduction of allograft rejection. Taken together, our data provide strong evidence that reduction of KMO in the graft is a key mediator of allograft rejection and loss. KMO can effectively improve allograft outcome by attenuating allograft rejection and maintaining graft barrier function.
Collapse
Affiliation(s)
- Randi Lassiter
- Department of Surgery, Medical College of Georgia at Augusta University, Augusta, GA, United States
| | - Todd D. Merchen
- Department of Surgery, Medical College of Georgia at Augusta University, Augusta, GA, United States
| | - Xuexiu Fang
- Division of Nephrology, Department of Medicine, Medical College of Georgia at Augusta University, Augusta, GA, United States
| | - Youli Wang
- Division of Nephrology, Department of Medicine, Medical College of Georgia at Augusta University, Augusta, GA, United States
| |
Collapse
|
9
|
Kimura H, Suda H, Kassai M, Endo M, Deai Y, Yahata M, Miyajima M, Isobe Y. N-(6-phenylpyridazin-3-yl)benzenesulfonamides as highly potent, brain-permeable, and orally active kynurenine monooxygenase inhibitors. Bioorg Med Chem Lett 2021; 33:127753. [PMID: 33359168 DOI: 10.1016/j.bmcl.2020.127753] [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] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 12/07/2020] [Accepted: 12/12/2020] [Indexed: 10/22/2022]
Abstract
Huntington's disease (HD) is one of the serious neurodegenerative diseases and no disease modifiers are available to date. The correction of unbalanced kynurenine pathway metabolites may be useful to treat disease progression and kynurenine monooxygenase (KMO) is considered an ideal drug target. A couple of KMO inhibitors have been reported, but their brain permeability was very poor. We found pyridazinylsulfonamide as a novel lead compound, and it was optimized to the brain-permeable and highly potent KMO inhibitor 12, which was equipotent with CHDI-340246 and superior to CHDI-340246 in terms of brain penetration. Compound 12 was effective in R6/2 mice (HD model mice), i.e. neuroprotective kynurenic acid was increased, whereas neurotoxic 3-hydroxykynurenine was suppressed. In addition, impaired cognitive function was improved. Therefore, the brain-permeable KMO inhibitor was considered to be a disease modifier for HD treatment.
Collapse
Affiliation(s)
- Hidenori Kimura
- Drug Research Division, Sumitomo Dainippon Pharma. Co., Ltd., 3-1-98, Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Hitoshi Suda
- Drug Research Division, Sumitomo Dainippon Pharma. Co., Ltd., 3-1-98, Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Momoe Kassai
- Drug Research Division, Sumitomo Dainippon Pharma. Co., Ltd., 3-1-98, Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Mika Endo
- Drug Research Division, Sumitomo Dainippon Pharma. Co., Ltd., 3-1-98, Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Yoko Deai
- Drug Research Division, Sumitomo Dainippon Pharma. Co., Ltd., 3-1-98, Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Masahiro Yahata
- Drug Research Division, Sumitomo Dainippon Pharma. Co., Ltd., 3-1-98, Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Mari Miyajima
- Drug Research Division, Sumitomo Dainippon Pharma. Co., Ltd., 3-1-98, Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Yoshiaki Isobe
- Drug Research Division, Sumitomo Dainippon Pharma. Co., Ltd., 3-1-98, Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan.
| |
Collapse
|
10
|
Maddison DC, Alfonso-Núñez M, Swaih AM, Breda C, Campesan S, Allcock N, Straatman-Iwanowska A, Kyriacou CP, Giorgini F. A novel role for kynurenine 3-monooxygenase in mitochondrial dynamics. PLoS Genet 2020; 16:e1009129. [PMID: 33170836 PMCID: PMC7654755 DOI: 10.1371/journal.pgen.1009129] [Citation(s) in RCA: 10] [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: 06/01/2020] [Accepted: 09/22/2020] [Indexed: 11/19/2022] Open
Abstract
The enzyme kynurenine 3-monooxygenase (KMO) operates at a critical branch-point in the kynurenine pathway (KP), the major route of tryptophan metabolism. As the KP has been implicated in the pathogenesis of several human diseases, KMO and other enzymes that control metabolic flux through the pathway are potential therapeutic targets for these disorders. While KMO is localized to the outer mitochondrial membrane in eukaryotic organisms, no mitochondrial role for KMO has been described. In this study, KMO deficient Drosophila melanogaster were investigated for mitochondrial phenotypes in vitro and in vivo. We find that a loss of function allele or RNAi knockdown of the Drosophila KMO ortholog (cinnabar) causes a range of morphological and functional alterations to mitochondria, which are independent of changes to levels of KP metabolites. Notably, cinnabar genetically interacts with the Parkinson's disease associated genes Pink1 and parkin, as well as the mitochondrial fission gene Drp1, implicating KMO in mitochondrial dynamics and mitophagy, mechanisms which govern the maintenance of a healthy mitochondrial network. Overexpression of human KMO in mammalian cells finds that KMO plays a role in the post-translational regulation of DRP1. These findings reveal a novel mitochondrial role for KMO, independent from its enzymatic role in the kynurenine pathway.
Collapse
Affiliation(s)
- Daniel C. Maddison
- Department of Genetics and Genome Biology, University of Leicester, Leicester, LE1 7RH, United Kingdom
| | - Mónica Alfonso-Núñez
- Department of Genetics and Genome Biology, University of Leicester, Leicester, LE1 7RH, United Kingdom
| | - Aisha M. Swaih
- Department of Genetics and Genome Biology, University of Leicester, Leicester, LE1 7RH, United Kingdom
| | - Carlo Breda
- Department of Genetics and Genome Biology, University of Leicester, Leicester, LE1 7RH, United Kingdom
- Leicester School of Allied Health Sciences, Faculty of Health and Life Sciences, De Montfort University, Leicester, LE1 9BH, United Kingdom
| | - Susanna Campesan
- Department of Genetics and Genome Biology, University of Leicester, Leicester, LE1 7RH, United Kingdom
| | - Natalie Allcock
- Core Biotechnology Services, Adrian Building, University of Leicester, University Road, Leicester, LE1 7RH, Leicestershire, United Kingdom
| | - Anna Straatman-Iwanowska
- Core Biotechnology Services, Adrian Building, University of Leicester, University Road, Leicester, LE1 7RH, Leicestershire, United Kingdom
| | - Charalambos P. Kyriacou
- Department of Genetics and Genome Biology, University of Leicester, Leicester, LE1 7RH, United Kingdom
| | - Flaviano Giorgini
- Department of Genetics and Genome Biology, University of Leicester, Leicester, LE1 7RH, United Kingdom
- * E-mail:
| |
Collapse
|
11
|
Zhang S, Sakuma M, Deora GS, Levy CW, Klausing A, Breda C, Read KD, Edlin CD, Ross BP, Wright Muelas M, Day PJ, O’Hagan S, Kell DB, Schwarcz R, Leys D, Heyes DJ, Giorgini F, Scrutton NS. A brain-permeable inhibitor of the neurodegenerative disease target kynurenine 3-monooxygenase prevents accumulation of neurotoxic metabolites. Commun Biol 2019; 2:271. [PMID: 31372510 PMCID: PMC6656724 DOI: 10.1038/s42003-019-0520-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [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: 07/30/2018] [Accepted: 06/28/2019] [Indexed: 12/16/2022] Open
Abstract
Dysregulation of the kynurenine pathway (KP) leads to imbalances in neuroactive metabolites associated with the pathogenesis of several neurodegenerative disorders, including Huntington's disease (HD). Inhibition of the enzyme kynurenine 3-monooxygenase (KMO) in the KP normalises these metabolic imbalances and ameliorates neurodegeneration and related phenotypes in several neurodegenerative disease models. KMO is thus a promising candidate drug target for these disorders, but known inhibitors are not brain permeable. Here, 19 new KMO inhibitors have been identified. One of these (1) is neuroprotective in a Drosophila HD model but is minimally brain penetrant in mice. The prodrug variant (1b) crosses the blood-brain barrier, releases 1 in the brain, thereby lowering levels of 3-hydroxykynurenine, a toxic KP metabolite linked to neurodegeneration. Prodrug 1b will advance development of targeted therapies against multiple neurodegenerative and neuroinflammatory diseases in which KP likely plays a role, including HD, Alzheimer's disease, and Parkinson's disease.
Collapse
Affiliation(s)
- Shaowei Zhang
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester, M1 7DN UK
| | - Michiyo Sakuma
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester, M1 7DN UK
| | - Girdhar S. Deora
- School of Pharmacy, The University of Queensland, Brisbane, Queensland 4072 Australia
| | - Colin W. Levy
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester, M1 7DN UK
| | - Alex Klausing
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD 21228 USA
| | - Carlo Breda
- Department of Genetics and Genome Biology, University of Leicester, Leicester, LE1 7RH UK
| | - Kevin D. Read
- Drug Discovery Unit, School of Life Sciences, University of Dundee, Dundee, Scotland DD1 5EH UK
| | | | - Benjamin P. Ross
- School of Pharmacy, The University of Queensland, Brisbane, Queensland 4072 Australia
| | - Marina Wright Muelas
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester, M1 7DN UK
| | - Philip J. Day
- Manchester Institute of Biotechnology and Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, M13 9PL UK
| | - Stephen O’Hagan
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester, M1 7DN UK
| | - Douglas B. Kell
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester, M1 7DN UK
| | - Robert Schwarcz
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD 21228 USA
| | - David Leys
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester, M1 7DN UK
| | - Derren J. Heyes
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester, M1 7DN UK
| | - Flaviano Giorgini
- Department of Genetics and Genome Biology, University of Leicester, Leicester, LE1 7RH UK
| | - Nigel S. Scrutton
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester, M1 7DN UK
| |
Collapse
|
12
|
Castellano-Gonzalez G, Jacobs KR, Don E, Cole NJ, Adams S, Lim CK, Lovejoy DB, Guillemin GJ. Kynurenine 3-Monooxygenase Activity in Human Primary Neurons and Effect on Cellular Bioenergetics Identifies New Neurotoxic Mechanisms. Neurotox Res 2019; 35:530-541. [PMID: 30666558 DOI: 10.1007/s12640-019-9997-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 12/20/2018] [Accepted: 01/08/2019] [Indexed: 12/17/2022]
Abstract
Upregulation of the kynurenine pathway (KP) of tryptophan metabolism is commonly observed in neurodegenerative disease. When activated, L-kynurenine (KYN) increases in the periphery and central nervous system where it is further metabolised to other neuroactive metabolites including 3-hydroxykynurenine (3-HK), kynurenic acid (KYNA) and quinolinic acid (QUIN). Particularly biologically relevant metabolites are 3-HK and QUIN, formed downstream of the enzyme kynurenine 3-monooxygenase (KMO) which plays a pivotal role in maintaining KP homeostasis. Indeed, excessive production of 3-HK and QUIN has been described in neurodegenerative disease including Alzheimer's disease and Huntington's disease. In this study, we characterise KMO activity in human primary neurons and identified new mechanisms by which KMO activation mediates neurotoxicity. We show that while transient activation of the KP promotes synthesis of the essential co-enzyme nicotinamide adenine dinucleotide (NAD+), allowing cells to meet short-term increased energy demands, chronic KMO activation induces production of reactive oxygen species (ROS), mitochondrial damage and decreases spare-respiratory capacity (SRC). We further found that these events generate a vicious-cycle, as mitochondrial dysfunction further shunts the KP towards the KMO branch of the KP to presumably enhance QUIN production. These mechanisms may be especially relevant in neurodegenerative disease as neurons are highly sensitive to oxidative stress and mitochondrial impairment.
Collapse
Affiliation(s)
- Gloria Castellano-Gonzalez
- Neuroinflammation Group, Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences (FMHS), Macquarie University, 2, Technology Place, North Ryde, NSW, 2109, Australia
| | - Kelly R Jacobs
- Neuroinflammation Group, Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences (FMHS), Macquarie University, 2, Technology Place, North Ryde, NSW, 2109, Australia
| | - Emily Don
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences (FMHS), Macquarie University, North Ryde, NSW, 2109, Australia
| | - Nicholas J Cole
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences (FMHS), Macquarie University, North Ryde, NSW, 2109, Australia
| | - Seray Adams
- Neuroinflammation Group, Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences (FMHS), Macquarie University, 2, Technology Place, North Ryde, NSW, 2109, Australia
| | - Chai K Lim
- Neuroinflammation Group, Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences (FMHS), Macquarie University, 2, Technology Place, North Ryde, NSW, 2109, Australia
| | - David B Lovejoy
- Neuroinflammation Group, Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences (FMHS), Macquarie University, 2, Technology Place, North Ryde, NSW, 2109, Australia.
| | - Gilles J Guillemin
- Neuroinflammation Group, Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences (FMHS), Macquarie University, 2, Technology Place, North Ryde, NSW, 2109, Australia.
| |
Collapse
|
13
|
Tufvesson-Alm M, Schwieler L, Schwarcz R, Goiny M, Erhardt S, Engberg G. Importance of kynurenine 3-monooxygenase for spontaneous firing and pharmacological responses of midbrain dopamine neurons: Relevance for schizophrenia. Neuropharmacology 2018; 138:130-139. [PMID: 29879409 DOI: 10.1016/j.neuropharm.2018.06.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [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: 01/18/2018] [Revised: 06/01/2018] [Accepted: 06/03/2018] [Indexed: 12/15/2022]
Abstract
Kynurenine 3-monooxygenase (KMO) is an essential enzyme of the kynurenine pathway, converting kynurenine into 3-hydroxykynurenine. Inhibition of KMO increases kynurenine, resulting in elevated levels of kynurenic acid (KYNA), an endogenous N-methyl-d-aspartate and α*7-nicotinic receptor antagonist. The concentration of KYNA is elevated in the brain of patients with schizophrenia, possibly as a result of a reduced KMO activity. In the present study, using in vivo single cell recording techniques, we investigated the electrophysiological characteristics of ventral tegmental area dopamine (VTA DA) neurons and their response to antipsychotic drugs in a KMO knock-out (K/O) mouse model. KMO K/O mice exhibited a marked increase in spontaneous VTA DA neuron activity as compared to wild-type (WT) mice. Furthermore, VTA DA neurons showed clear-cut, yet qualitatively opposite, responses to the antipsychotic drugs haloperidol and clozapine in the two genotypes. The anti-inflammatory drug parecoxib successfully lowered the firing activity of VTA DA neurons in KMO K/O, but not in WT mice. Minocycline, an antibiotic and anti-inflammatory drug, produced no effect in this regard. Taken together, the present data further support the usefulness of KMO K/O mice for studying distinct aspects of the pathophysiology and pharmacological treatment of psychiatric disorders such as schizophrenia.
Collapse
Affiliation(s)
| | - Lilly Schwieler
- Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden
| | - Robert Schwarcz
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Michel Goiny
- Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden
| | - Sophie Erhardt
- Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden
| | - Göran Engberg
- Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden; Department of Physiology and Pharmacology, Karolinska Institute, Biomedicum 5C, 171 77, Stockholm, Sweden.
| |
Collapse
|
14
|
Wang J, Li X, He S, Hu L, Guo J, Huang X, Hu J, Qi Y, Chen B, Shang D, Wen Y. Regulation of the kynurenine metabolism pathway by Xiaoyao San and the underlying effect in the hippocampus of the depressed rat. J Ethnopharmacol 2018; 214:13-21. [PMID: 29217494 DOI: 10.1016/j.jep.2017.11.037] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [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: 10/29/2016] [Revised: 10/31/2017] [Accepted: 11/30/2017] [Indexed: 06/07/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Xiaoyao San (XYS) is a classic Chinese herbal formula for treatment of depression. The present study aimed to investigate the antidepressant effects of XYS in a rat model of chronic unpredictable mild stress (CUMS) and the underlying mechanisms. MATERIALS AND METHODS A CUMS rat model of depression was established via 4 weeks of unpredictable stimulation. Then the rats were orally administered paroxetine and XYS for 2 weeks with continued stress. Behavioral assessments, including an open field test (OFT), sucrose preference test (SPT) and forced swim test (FST), were conducted to evaluate the antidepressant effects of XYS. The concentrations in rat plasma of tryptophan (Trp) and its metabolic products, including kynurenine (Kyn) and quinolinic acid (QUIN), were determined using high performance liquid chromatography tandem mass spectrometry with electrochemical detection (HPLC-MS/MS). The mRNA and protein levels in rat hippocampus of depression-related brain derived neurotrophic factor (BDNF), cyclic AMP response element binding protein (CREB) and nerve cell adhesion molecule (NCAM) were determined by real-time qPCR and Western blot, respectively. Enzyme Linked Immunosorbent Assay (ELISA) was used to detect the activities of indoleamine 2,3-dioxygenase (IDO) and kynurenine-3-monooxygenase (KMO) in rat plasma. RESULTS The results showed that a successful CUMS rat model was established through 4 weeks of continuous unpredictable stimulation, as indicated by the significant decrease in locomotor activity and increase in immobility time in the OFT, reduction in body weight and food intake etc. Compared with the normal group, the concentrations of Kyn and QUIN had significantly (p < 0.05) decreased at day 28 in the control group, but then improved after drug treatment with paroxetine and XYS. There were no obvious changes in the activities of IDO and KMO. Compared with the normal group, the mRNA of NCAM, CREB and BDNF were significantly down-regulated (p < 0.001) in the control group, BDNF gene was up-regulated by paroxetine or XYS treatment, NCAM and CREB gene did not change in XYS group, protein expressions of BDNF and CREB were significantly increased, and NCAM was significantly reduced (p < 0.05). CONCLUSIONS XYS reversed the abnormalities of the tryptophan-kynurenine metabolic pathways in depressed rats and achieved an excellent antidepressant effect. Its direct impact may be observed as changes in biological indicators in rat hippocampus tissue.
Collapse
Affiliation(s)
- Jiajia Wang
- The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), 36 Mingxin Road, Guangzhou 510370, PR China; Guangzhou University of Traditional Chinese Medicine, 16 Airport Road, Guangzhou 510405, PR China
| | - Xiaofang Li
- The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), 36 Mingxin Road, Guangzhou 510370, PR China
| | - Shugui He
- Guangzhou University of Traditional Chinese Medicine, 16 Airport Road, Guangzhou 510405, PR China
| | - Lijun Hu
- The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), 36 Mingxin Road, Guangzhou 510370, PR China
| | - Jiewen Guo
- Guangzhou Hospital of Traditional Chinese Medicine, 16 Zhuji Road, Guangzhou 510130, PR China
| | - Xiangning Huang
- Guangzhou Xinhai Hospital, Guangzhou, 167 Xingang West Road, Guangzhou 510300, PR China
| | - Jinqing Hu
- The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), 36 Mingxin Road, Guangzhou 510370, PR China
| | - Yaoqun Qi
- Guangzhou University of Traditional Chinese Medicine, 16 Airport Road, Guangzhou 510405, PR China
| | - Bin Chen
- Guangzhou University of Traditional Chinese Medicine, 16 Airport Road, Guangzhou 510405, PR China
| | - Dewei Shang
- The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), 36 Mingxin Road, Guangzhou 510370, PR China.
| | - Yuguan Wen
- The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), 36 Mingxin Road, Guangzhou 510370, PR China.
| |
Collapse
|
15
|
Kim HT, Na BK, Chung J, Kim S, Kwon SK, Cha H, Son J, Cho JM, Hwang KY. Structural Basis for Inhibitor-Induced Hydrogen Peroxide Production by Kynurenine 3-Monooxygenase. Cell Chem Biol 2018; 25:426-438.e4. [PMID: 29429898 DOI: 10.1016/j.chembiol.2018.01.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [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: 08/02/2017] [Revised: 10/17/2017] [Accepted: 01/08/2018] [Indexed: 11/18/2022]
Abstract
Kynurenine 3-monooxygenase (KMO) inhibitors have been developed for the treatment of neurodegenerative disorders. The mechanisms of flavin reduction and hydrogen peroxide production by KMO inhibitors are unknown. Herein, we report the structure of human KMO and crystal structures of Saccharomyces cerevisiae (sc) and Pseudomonas fluorescens (pf) KMO with Ro 61-8048. Proton transfer in the hydrogen bond network triggers flavin reduction in p-hydroxybenzoate hydroxylase, but the mechanism triggering flavin reduction in KMO is different. Conformational changes via π-π interactions between the loop above the flavin and substrate or non-substrate effectors lead to disorder of the C-terminal α helix in scKMO and shifts of domain III in pfKMO, stimulating flavin reduction. Interestingly, Ro 61-8048 has two different binding modes. It acts as a competitive inhibitor in scKMO and as a non-substrate effector in pfKMO. These findings provide understanding of the catalytic cycle of KMO and insight for structure-based drug design of KMO inhibitors.
Collapse
Affiliation(s)
- Hyun Tae Kim
- Crystalgenomics, Inc., 5F, Tower A, Korea Bio Park 700, Daewangpangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 13524, Korea; Division of Biotechnology, College of Life Sciences and Biotechnology, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea
| | - Byeong Kwan Na
- Crystalgenomics, Inc., 5F, Tower A, Korea Bio Park 700, Daewangpangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 13524, Korea
| | - Jiwoung Chung
- Crystalgenomics, Inc., 5F, Tower A, Korea Bio Park 700, Daewangpangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 13524, Korea
| | - Sulhee Kim
- Division of Biotechnology, College of Life Sciences and Biotechnology, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea
| | - Sool Ki Kwon
- Crystalgenomics, Inc., 5F, Tower A, Korea Bio Park 700, Daewangpangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 13524, Korea
| | - Hyunju Cha
- Crystalgenomics, Inc., 5F, Tower A, Korea Bio Park 700, Daewangpangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 13524, Korea
| | - Jonghyeon Son
- Division of Biotechnology, College of Life Sciences and Biotechnology, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea
| | - Joong Myung Cho
- Crystalgenomics, Inc., 5F, Tower A, Korea Bio Park 700, Daewangpangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 13524, Korea.
| | - Kwang Yeon Hwang
- Division of Biotechnology, College of Life Sciences and Biotechnology, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea.
| |
Collapse
|
16
|
Wilson K, Webster SP, Iredale JP, Zheng X, Homer NZ, Pham NT, Auer M, Mole DJ. Detecting drug-target binding in cells using fluorescence-activated cell sorting coupled with mass spectrometry analysis. Methods Appl Fluoresc 2017; 6:015002. [PMID: 28901950 DOI: 10.1088/2050-6120/aa8c60] [Citation(s) in RCA: 7] [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] [Indexed: 12/19/2022]
Abstract
The assessment of drug-target engagement for determining the efficacy of a compound inside cells remains challenging, particularly for difficult target proteins. Existing techniques are more suited to soluble protein targets. Difficult target proteins include those with challenging in vitro solubility, stability or purification properties that preclude target isolation. Here, we report a novel technique that measures intracellular compound-target complex formation, as well as cellular permeability, specificity and cytotoxicity-the toxicity-affinity-permeability-selectivity (TAPS) technique. The TAPS assay is exemplified here using human kynurenine 3-monooxygenase (KMO), a challenging intracellular membrane protein target of significant current interest. TAPS confirmed target binding of known KMO inhibitors inside cells. We conclude that the TAPS assay can be used to facilitate intracellular hit validation on most, if not all intracellular drug targets.
Collapse
Affiliation(s)
- Kris Wilson
- Drug Discovery Core, University/BHF Centre for Cardiovascular Science, Queen's Medical Research Institute, The University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Sternberg JM, Forrest CM, Dalton RN, Turner C, Rodgers J, Stone TW, Kennedy PGE. Kynurenine Pathway Activation in Human African Trypanosomiasis. J Infect Dis 2017; 215:806-812. [PMID: 28013248 PMCID: PMC5388295 DOI: 10.1093/infdis/jiw623] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [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: 10/20/2016] [Accepted: 12/09/2016] [Indexed: 11/30/2022] Open
Abstract
Background The kynurenine pathway of tryptophan oxidation is associated with central nervous system (CNS) inflammatory pathways. Inhibition of this pathway ameliorates CNS inflammation in rodent models of the late (meningoencephalitic) stage of human African trypanosomiasis (HAT). In this study, we evaluate whether the kynurenine pathway is activated in clinical HAT and associated with CNS inflammatory responses. Methods We measured cerebrospinal fluid (CSF) tryptophan and kynurenine metabolite concentrations in patients infected with Trypanosoma brucei rhodesiense, using liquid chromatography-mass spectrometry. Results Kynurenine concentration in CSF was increased in both the early and late stages of disease, with a progressive increase in tryptophan oxidation associated with stage progression. Kynurenine pathway activation was associated with increases in neuroinflammatory markers, but there was no clear relationship to neurological symptoms. Conclusions CNS kynurenine pathway activation occurs during HAT, including cases prior to the current diagnostic cutoff for late-stage infection, providing evidence for early CNS involvement in HAT. Metabolite data demonstrate that the kynurenine-3-monooxygenase and kynurenine aminotransferase branches of the kynurenine pathway are active. The association between tryptophan oxidation and CNS inflammatory responses as measured by CSF interleukin 6 (IL-6) concentration supports a role of kynurenine metabolites in the inflammatory pathogenesis of late-stage HAT.
Collapse
Affiliation(s)
- Jeremy M Sternberg
- Institute of Biological and Environmental Sciences, University of Aberdeen, UK
| | - Caroline M Forrest
- Institute of Neuroscience and Psychology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - R Neil Dalton
- WellChild Laboratory, Evelina London Children's Hospital, King's College London, United Kingdom
| | - Charles Turner
- WellChild Laboratory, Evelina London Children's Hospital, King's College London, United Kingdom
| | - Jean Rodgers
- Institute of Biodiversity, Animal Health, and Comparative Medicine, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
| | - Trevor W Stone
- Institute of Neuroscience and Psychology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Peter G E Kennedy
- Department of Neurology, College of Medical, Veterinary, and Life Sciences, University of Glasgow, UK
| |
Collapse
|
18
|
Amin SA, Adhikari N, Jha T, Gayen S. First molecular modeling report on novel arylpyrimidine kynurenine monooxygenase inhibitors through multi-QSAR analysis against Huntington's disease: A proposal to chemists! Bioorg Med Chem Lett 2016; 26:5712-5718. [PMID: 27838184 DOI: 10.1016/j.bmcl.2016.10.058] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [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: 07/19/2016] [Revised: 09/30/2016] [Accepted: 10/20/2016] [Indexed: 11/18/2022]
Abstract
Huntington's disease (HD) is caused by mutation of huntingtin protein (mHtt) leading to neuronal cell death. The mHtt induced toxicity can be rescued by inhibiting the kynurenine monooxygenase (KMO) enzyme. Therefore, KMO is a promising drug target to address the neurodegenerative disorders such as Huntington's diseases. Fiftysix arylpyrimidine KMO inhibitors are structurally explored through regression and classification based multi-QSAR modeling, pharmacophore mapping and molecular docking approaches. Moreover, ten new compounds are proposed and validated through the modeling that may be effective in accelerating Huntington's disease drug discovery efforts.
Collapse
Affiliation(s)
- Sk Abdul Amin
- Laboratory of Drug Design and Discovery, Department of Pharmaceutical Sciences, Dr. Harisingh Gour University, Sagar 470003, Madhya Pradesh, India; Natural Science Laboratory, Division of Medicinal and Pharmaceutical Chemistry, Department of Pharmaceutical Technology, PO Box 17020, Jadavpur University, Kolkata 700032, West Bengal, India
| | - Nilanjan Adhikari
- Natural Science Laboratory, Division of Medicinal and Pharmaceutical Chemistry, Department of Pharmaceutical Technology, PO Box 17020, Jadavpur University, Kolkata 700032, West Bengal, India
| | - Tarun Jha
- Natural Science Laboratory, Division of Medicinal and Pharmaceutical Chemistry, Department of Pharmaceutical Technology, PO Box 17020, Jadavpur University, Kolkata 700032, West Bengal, India
| | - Shovanlal Gayen
- Laboratory of Drug Design and Discovery, Department of Pharmaceutical Sciences, Dr. Harisingh Gour University, Sagar 470003, Madhya Pradesh, India
| |
Collapse
|
19
|
Beaumont V, Mrzljak L, Dijkman U, Freije R, Heins M, Rassoulpour A, Tombaugh G, Gelman S, Bradaia A, Steidl E, Gleyzes M, Heikkinen T, Lehtimäki K, Puoliväli J, Kontkanen O, Javier RM, Neagoe I, Deisemann H, Winkler D, Ebneth A, Khetarpal V, Toledo-Sherman L, Dominguez C, Park LC, Munoz-Sanjuan I. The novel KMO inhibitor CHDI-340246 leads to a restoration of electrophysiological alterations in mouse models of Huntington's disease. Exp Neurol 2016; 282:99-118. [PMID: 27163548 DOI: 10.1016/j.expneurol.2016.05.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [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: 12/03/2015] [Revised: 04/28/2016] [Accepted: 05/05/2016] [Indexed: 11/18/2022]
Abstract
Dysregulation of the kynurenine (Kyn) pathway has been associated with the progression of Huntington's disease (HD). In particular, elevated levels of the kynurenine metabolites 3-hydroxy kynurenine (3-OH-Kyn) and quinolinic acid (Quin), have been reported in the brains of HD patients as well as in rodent models of HD. The production of these metabolites is controlled by the activity of kynurenine mono-oxygenase (KMO), an enzyme which catalyzes the synthesis of 3-OH-Kyn from Kyn. In order to determine the role of KMO in the phenotype of mouse models of HD, we have developed a potent and selective KMO inhibitor termed CHDI-340246. We show that this compound, when administered orally to transgenic mouse models of HD, potently and dose-dependently modulates the Kyn pathway in peripheral tissues and in the central nervous system. The administration of CHDI-340246 leads to an inhibition of the formation of 3-OH-Kyn and Quin, and to an elevation of Kyn and Kynurenic acid (KynA) levels in brain tissues. We show that administration of CHDI-340246 or of Kyn and of KynA can restore several electrophysiological alterations in mouse models of HD, both acutely and after chronic administration. However, using a comprehensive panel of behavioral tests, we demonstrate that the chronic dosing of a selective KMO inhibitor does not significantly modify behavioral phenotypes or natural progression in mouse models of HD.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Larry C Park
- CHDI Foundation/CHDI Management Inc., Los Angeles, USA
| | | |
Collapse
|
20
|
Grégoire L, Rassoulpour A, Guidetti P, Samadi P, Bédard PJ, Izzo E, Schwarcz R, Di Paolo T. Prolonged kynurenine 3-hydroxylase inhibition reduces development of levodopa-induced dyskinesias in parkinsonian monkeys. Behav Brain Res 2008; 186:161-7. [PMID: 17868931 DOI: 10.1016/j.bbr.2007.08.007] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2007] [Revised: 08/02/2007] [Accepted: 08/05/2007] [Indexed: 11/20/2022]
Abstract
Increased glutamatergic activity is believed to play a significant role in the development of levodopa-induced dyskinesias (LID). LID may therefore be attenuated by a reduction in glutamatergic function. This was tested pharmacologically in MPTP monkeys by increasing the formation of kynurenic acid (KYNA), a tryptophan metabolite that inhibits glutamate release and also blocks NMDA receptors directly. KYNA synthesis was stimulated by prolonged systemic administration of the kynurenine 3-hydroxylase inhibitor Ro 61-8048. Four MPTP cynomolgus monkeys received l-dopa (LD; 100mg) with benserazide (25 mg) for one month. Progressively, all these animals developed LID. Four other MPTP monkeys received Ro 61-8048 (50mg/kg) daily 3 h before administration of LD/benserazide for one month. The addition of Ro 61-8048 reduced the development of LID but did not affect the antiparkinsonian efficacy of LD. Moreover, Ro 61-8048 administration caused sustained increases in serum kynurenine and KYNA concentrations, which reverted to basal values 24 h after the last treatment. This effect of Ro 61-8048 was less pronounced in the CSF. These results demonstrate that long-lasting elevation of KYNA levels caused by prolonged inhibition of kynurenine 3-hydroxylase is associated with a significant reduction in LID but does not compromise the benefits of chronic LD therapy.
Collapse
Affiliation(s)
- Laurent Grégoire
- Molecular Endocrinology and Oncology Research Center, CHUQ, CHUL Pavillon and Faculty of Pharmacy, Laval University, Québec, PQ, Canada
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Ceresoli-Borroni G, Guidetti P, Amori L, Pellicciari R, Schwarcz R. Perinatal kynurenine 3-hydroxylase inhibition in rodents: pathophysiological implications. J Neurosci Res 2007; 85:845-54. [PMID: 17279543 DOI: 10.1002/jnr.21183] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [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: 11/05/2022]
Abstract
The kynurenine pathway (KP) of tryptophan degradation contains three neuroactive metabolites: the neuroinhibitory agent kynurenic acid (KYNA) and, in a competing branch, the free radical generator 3-hydroxykynurenine (3-HK) and the excitotoxin quinolinic acid (QUIN). These three "kynurenines" derive from a common precursor, L-kynurenine, and are recognized for their role in brain physiology and pathophysiology. Inhibition of kynurenine 3-hydroxylase, the enzyme responsible for 3-HK formation, shifts KP metabolism in the mature brain toward enhanced KYNA formation. We now tested the cerebral effects of kynurenine 3-hydroxylase inhibition in immature rodents. Rat pups treated with the kynurenine 3-hydroxylase inhibitor UPF 648 (30 mg/kg, i.p.) 10 min after birth showed substantial increases in cerebral and liver kynurenine and KYNA levels up to 24 hr later, whereas 3-HK and QUIN levels were simultaneously decreased. Administered to pregnant rats or mice on the last day of gestation, UPF 648 (50 mg/kg, i.p.) produced qualitatively similar changes (i.e., large increases in kynurenine and KYNA and reductions in 3-HK and QUIN) in the brain and liver of the offspring. Rat pups delivered by UPF 648-treated mothers and immediately exposed to neonatal asphyxia showed further enhanced brain KYNA levels. These studies demonstrate that acute kynurenine 3-hydroxylase inhibition effectively shifts cerebral KP metabolism in neonatal rodents toward increased KYNA formation. Selective inhibitors of this enzyme may therefore provide neuroprotection in newborns and will also be useful for the experimental evaluation of the long-term effects of perinatal KP impairment.
Collapse
Affiliation(s)
- Gianpiera Ceresoli-Borroni
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland 21228, USA
| | | | | | | | | |
Collapse
|
22
|
Han Q, Beerntsen BT, Li J. The tryptophan oxidation pathway in mosquitoes with emphasis on xanthurenic acid biosynthesis. J Insect Physiol 2007; 53:254-63. [PMID: 17070835 PMCID: PMC2577175 DOI: 10.1016/j.jinsphys.2006.09.004] [Citation(s) in RCA: 46] [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] [Subscribe] [Scholar Register] [Received: 04/21/2006] [Revised: 09/01/2006] [Accepted: 09/04/2006] [Indexed: 05/12/2023]
Abstract
Oxidation of tryptophan to kynurenine and 3-hydroxykynurenine (3-HK) is the major catabolic pathway in mosquitoes. However, 3-HK is oxidized easily under physiological conditions, resulting in the production of reactive radical species. To overcome this problem, mosquitoes have developed an efficient mechanism to prevent 3-HK from accumulating by converting this chemically reactive compound to the chemically stable xanthurenic acid. Interestingly, 3-HK is a precursor for the production of compound eye pigments during the pupal and early adult stages; consequently, mosquitoes need to preserve and transport 3-HK for compound eye pigmentation in pupae and adults. This review summarizes the tryptophan oxidation pathway, compares and contrasts the mosquito tryptophan oxidation pathway with other model species, and discusses possible driving forces leading to the functional adaptation and evolution of enzymes involved in the mosquito tryptophan oxidation pathway.
Collapse
Affiliation(s)
- Qian Han
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
| | | | | |
Collapse
|
23
|
Bellac CL, Coimbra RS, Christen S, Leib SL. Pneumococcal meningitis causes accumulation of neurotoxic kynurenine metabolites in brain regions prone to injury. Neurobiol Dis 2006; 24:395-402. [PMID: 16956766 DOI: 10.1016/j.nbd.2006.07.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [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: 06/14/2006] [Revised: 07/20/2006] [Accepted: 07/25/2006] [Indexed: 10/24/2022] Open
Abstract
Pneumococcal meningitis (PM) is characterized by an intense inflammatory host reaction that contributes to the development of cortical necrosis and hippocampal apoptosis. Inflammatory conditions in the brain are known to induce tryptophan degradation along the kynurenine pathway, resulting in accumulation of neurotoxic metabolites. In the present study, we investigated the contribution of the kynurenine pathway to brain injury in experimental PM by measuring the concentration of its metabolites and the enzymatic activities and mRNA levels of its major enzymes in the vulnerable brain regions. In the late phase of acute PM, we found a significant transcriptional upregulation of kynurenine-3-hydroxylase and an accumulation of the neurotoxic metabolites 3-hydroxykynurenine (3-HKYN) and 3-hydroxyanthranilic acid in cortex and hippocampus. The positive correlation between the concentration of 3-HKYN and the extent of hippocampal apoptosis adds support to the concept that 3-HKYN contributes to brain injury in PM.
Collapse
Affiliation(s)
- Caroline L Bellac
- Institute for Infectious Diseases, University of Bern, Friedbuehlstrasse 51, PO Box 61, CH-3010 Bern, Switzerland
| | | | | | | |
Collapse
|
24
|
Aoyama N, Takahashi N, Saito S, Maeno N, Ishihara R, Ji X, Miura H, Ikeda M, Suzuki T, Kitajima T, Yamanouchi Y, Kinoshita Y, Yoshida K, Iwata N, Inada T, Ozaki N. Association study between kynurenine 3-monooxygenase gene and schizophrenia in the Japanese population. Genes Brain Behav 2006; 5:364-8. [PMID: 16716206 DOI: 10.1111/j.1601-183x.2006.00231.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Several lines of evidence suggest that metabolic changes in the kynurenic acid (KYNA) pathway are related to the etiology of schizophrenia. The inhibitor of kynurenine 3-monooxygenase (KMO) is known to increase KYNA levels, and the KMO gene is located in the chromosome region associated with schizophrenia, 1q42-q44. Single-marker and haplotype analyses for 6-tag single nucleotide polymorphisms (SNPs) of KMO were performed (cases = 465, controls = 440). Significant association of rs2275163 with schizophrenia was observed by single-marker comparisons (P = 0.032) and haplotype analysis including this SNP (P = 0.0049). Significant association of rs2275163 and haplotype was not replicated using a second, independent set of samples (cases = 480, controls = 448) (P = 0.706 and P = 0.689, respectively). These results suggest that the KMO is unlikely to be related to the development of schizophrenia in Japanese.
Collapse
Affiliation(s)
- N Aoyama
- Department of Psychiatry, Nagoua University Graduate School of Medicine, Nagoya, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|