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Kumar R, Vitvitsky V, Sethaudom A, Singhal R, Solanki S, Alibeckoff S, Hiraki HL, Bell HN, Andren A, Baker BM, Lyssiotis CA, Shah YM, Banerjee R. Sulfide oxidation promotes hypoxic angiogenesis and neovascularization. Nat Chem Biol 2024; 20:1294-1304. [PMID: 38509349 PMCID: PMC11584973 DOI: 10.1038/s41589-024-01583-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 02/20/2024] [Indexed: 03/22/2024]
Abstract
Angiogenic programming in the vascular endothelium is a tightly regulated process for maintaining tissue homeostasis and is activated in tissue injury and the tumor microenvironment. The metabolic basis of how gas signaling molecules regulate angiogenesis is elusive. Here, we report that hypoxic upregulation of ·NO in endothelial cells reprograms the transsulfuration pathway to increase biogenesis of hydrogen sulfide (H2S), a proangiogenic metabolite. However, decreased H2S oxidation due to sulfide quinone oxidoreductase (SQOR) deficiency synergizes with hypoxia, inducing a reductive shift and limiting endothelial proliferation that is attenuated by dissipation of the mitochondrial NADH pool. Tumor xenografts in whole-body (WBCreSqorfl/fl) and endothelial-specific (VE-cadherinCre-ERT2Sqorfl/fl) Sqor-knockout mice exhibit lower mass and angiogenesis than control mice. WBCreSqorfl/fl mice also exhibit decreased muscle angiogenesis following femoral artery ligation compared to control mice. Collectively, our data reveal the molecular intersections between H2S, O2 and ·NO metabolism and identify SQOR inhibition as a metabolic vulnerability for endothelial cell proliferation and neovascularization.
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Affiliation(s)
- Roshan Kumar
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Victor Vitvitsky
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Apichaya Sethaudom
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Rashi Singhal
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Sumeet Solanki
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Sydney Alibeckoff
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Harrison L Hiraki
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Hannah N Bell
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Anthony Andren
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Brendon M Baker
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Costas A Lyssiotis
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
- Rogel Cancer Center, University of Michigan, Ann Arbor, MI, USA
| | - Yatrik M Shah
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
- Rogel Cancer Center, University of Michigan, Ann Arbor, MI, USA
| | - Ruma Banerjee
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI, USA.
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2
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Pedre B. A guide to genetically-encoded redox biosensors: State of the art and opportunities. Arch Biochem Biophys 2024; 758:110067. [PMID: 38908743 DOI: 10.1016/j.abb.2024.110067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2024] [Revised: 06/18/2024] [Accepted: 06/19/2024] [Indexed: 06/24/2024]
Abstract
Genetically-encoded redox biosensors have become invaluable tools for monitoring cellular redox processes with high spatiotemporal resolution, coupling the presence of the redox-active analyte with a change in fluorescence signal that can be easily recorded. This review summarizes the available fluorescence recording methods and presents an in-depth classification of the redox biosensors, organized by the analytes they respond to. In addition to the fluorescent protein-based architectures, this review also describes the recent advances on fluorescent, chemigenetic-based redox biosensors and other emerging chemigenetic strategies. This review examines how these biosensors are designed, the biosensors sensing mechanism, and their practical advantages and disadvantages.
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Affiliation(s)
- Brandán Pedre
- Biochemistry, Molecular and Structural Biology Unit, Department of Chemistry, KU Leuven, Belgium.
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3
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Xu X, Zhu J, Fang L, Zou Z, Yuan J, Peng M, Yu G, Wu D, Liu Y, Tang J. Exome sequencing identified novel variants in three Chinese patients with 5,10-methenyltetrahydrofolate synthetase deficiency. Front Genet 2023; 14:1236849. [PMID: 37795244 PMCID: PMC10545881 DOI: 10.3389/fgene.2023.1236849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 08/25/2023] [Indexed: 10/06/2023] Open
Abstract
5,10-methenyltetrahydrofolate synthetase (MTHFS) deficiency is a folate metabolism disorder known as a rare autosomal recessive neurodevelopmental disorder (MIM: #618367). With central nervous system involvements, it is mainly characterized by developmental delay, epilepsy, microcephaly, hypertonia, and cranial nerves involvement. Here, we report three new cases with MTHFS deficiency from two non-consanguineous Chinese families. All patients showed white matter dysplasia and global developmental delay, of which only patient 1 and 2 manifested tonic-clonic seizures. Moreover, patient 2 had severe eczema and patient 3 had recurrent diarrhea. Both phenotypic features are firstly found in MTHFS deficiency. Trio whole-exome sequencing and sanger sequencing were used to identify four novel variants, p.Y169Tfs*17, p.S53F, c.117+1delG, and p.E61G in the MTHFS gene. The identification of four novel pathogenic variants and varied clinical features in three affected patients expands the genotype and phenotype spectrum of MTHFS deficiency. We also reviewed all cases of MTHFS deficiency that had previously been reported. The experience of diagnosis and treatment from these cases provides us a more comprehensive understanding of this rare disease.
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Affiliation(s)
- Xiaoyan Xu
- Pediatric Neurorehabilitation Center, Pediatric Department, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Jing Zhu
- Pediatric Neurorehabilitation Center, Pediatric Department, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Liwei Fang
- Pediatric Neurorehabilitation Center, Pediatric Department, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Zhuo Zou
- Department of Rehabilitation, Kunming Children’s Hospital, Kunming Medical University, Kunming, Yunnan, China
| | - Jingjing Yuan
- Pediatric Neurorehabilitation Center, Pediatric Department, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Min Peng
- Chigene (Beijing) Translational Medical Research Center Co, Ltd, Beijing, China
| | - Guoliang Yu
- Chigene (Beijing) Translational Medical Research Center Co, Ltd, Beijing, China
| | - De Wu
- Pediatric Neurorehabilitation Center, Pediatric Department, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Yun Liu
- Department of Rehabilitation, Kunming Children’s Hospital, Kunming Medical University, Kunming, Yunnan, China
| | - Jiulai Tang
- Pediatric Neurorehabilitation Center, Pediatric Department, The First Affiliated Hospital of Anhui Medical University, Hefei, China
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4
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Mou YJ, Ma YT, Yuan X, Wang M, Liu Y, Pei CS, Liu CF, Hou XO, Hu LF. Cystathionine β-Synthase Suppresses NLRP3 Inflammasome Activation via Redox Regulation in Microglia. Antioxid Redox Signal 2023. [PMID: 37464816 DOI: 10.1089/ars.2022.0174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
Aims: Cystathionine β-synthase (CBS) is essential for homocysteine (Hcy) transsulfuration, yielding cysteine as a common precursor of hydrogen sulfide (H2S), glutathione (GSH), and other sulfur molecules, which produce neuroprotective effects in neurological conditions. We previously reported a disruption of microglial CBS/H2S signaling in a Parkinson's disease (PD) mouse model. Yet, it remains unclear whether CBS affects nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain-containing 3 (NLRP3) inflammasome activity and other pathologies in PD. Results: Microglial CBS expression decreased after lipopolysaccharide (LPS) stimulation. Elevated GSSG (the oxidized GSH) content and decreased H2S generation were found in the brains of microglial cbs conditional-knockout (cbscKO) mice, whereas serum and brain Hcy levels remained unaltered. Moreover, microglial cbscKO mice were susceptible to NLRP3 inflammasome activation and dopaminergic neuron losses caused by LPS injection into the substantia nigra, whereas cbs overexpression or activation produced opposite effects. In vitro studies showed that cbs overexpression or activation suppressed microglial NLRP3 inflammasome activation and interleukin (IL)-1β secretion by reducing mitochondrial reactive oxygen species (mitoROS) level. Conversely, ablation of cbs enhanced NLRP3 expression and mitoROS generation and augmented microglial NLRP3 inflammasome activity in response to adenosine triphosphate challenge, which was blocked by the mitoROS scavenger. Innovation and Conclusion: The study demonstrated an elevated GSSG level and reduced H2S generation, which correlated with a susceptible status of microglia in the brain of cbscKO mice. Our findings reveal a critical role of CBS in restraining the microglial NLRP3 inflammasome by controlling redox homeostasis and highlight that activation or upregulation of CBS may become a potential strategy for PD treatment.
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Affiliation(s)
- Yu-Jie Mou
- Department of Neurology and Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou, China
- Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Ya-Ting Ma
- Department of Neurology and Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou, China
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Xin Yuan
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Miao Wang
- Department of Neurology and Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou, China
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Yang Liu
- Department of Neurology and Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou, China
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Chong-Shuang Pei
- Department of Neurology and Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou, China
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Chun-Feng Liu
- Department of Neurology and Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou, China
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Xiao-Ou Hou
- Department of Neurology and Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou, China
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Li-Fang Hu
- Department of Neurology and Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou, China
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
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5
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Pérez-Sala D, Pajares MA. Appraising the Role of Astrocytes as Suppliers of Neuronal Glutathione Precursors. Int J Mol Sci 2023; 24:ijms24098059. [PMID: 37175763 PMCID: PMC10179008 DOI: 10.3390/ijms24098059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 04/25/2023] [Accepted: 04/25/2023] [Indexed: 05/15/2023] Open
Abstract
The metabolism and intercellular transfer of glutathione or its precursors may play an important role in cellular defense against oxidative stress, a common hallmark of neurodegeneration. In the 1990s, several studies in the Neurobiology field led to the widely accepted notion that astrocytes produce large amounts of glutathione that serve to feed neurons with precursors for glutathione synthesis. This assumption has important implications for health and disease since a reduction in this supply from astrocytes could compromise the capacity of neurons to cope with oxidative stress. However, at first glance, this shuttling would imply a large energy expenditure to get to the same point in a nearby cell. Thus, are there additional underlying reasons for this expensive mechanism? Are neurons unable to import and/or synthesize the three non-essential amino acids that are the glutathione building blocks? The rather oxidizing extracellular environment favors the presence of cysteine (Cys) as cystine (Cis), less favorable for neuronal import. Therefore, it has also been proposed that astrocytic GSH efflux could induce a change in the redox status of the extracellular space nearby the neurons, locally lowering the Cis/Cys ratio. This astrocytic glutathione release would also increase their demand for precursors, stimulating Cis uptake, which these cells can import, further impacting the local decline of the Cis/Cys ratio, in turn, contributing to a more reduced extracellular environment and subsequently favoring neuronal Cys import. Here, we revisit the experimental evidence that led to the accepted hypothesis of astrocytes acting as suppliers of neuronal glutathione precursors, considering recent data from the Human Protein Atlas. In addition, we highlight some potential drawbacks of this hypothesis, mainly supported by heterogeneous cellular models. Finally, we outline additional and more cost-efficient possibilities by which astrocytes could support neuronal glutathione levels, including its shuttling in extracellular vesicles.
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Affiliation(s)
- Dolores Pérez-Sala
- Department of Structural and Chemical Biology, Centro de Investigaciones Biológicas Margarita Salas (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - María A Pajares
- Department of Structural and Chemical Biology, Centro de Investigaciones Biológicas Margarita Salas (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain
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6
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Kumar R, Vitvitsky V, Seth P, Hiraki HL, Bell H, Andren A, Singhal R, Baker BM, Lyssiotis CA, Shah YM, Banerjee R. Sulfide oxidation promotes hypoxic angiogenesis and neovascularization. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.14.532677. [PMID: 36993187 PMCID: PMC10055101 DOI: 10.1101/2023.03.14.532677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Angiogenic programming in the vascular endothelium is a tightly regulated process to maintain tissue homeostasis and is activated in tissue injury and the tumor microenvironment. The metabolic basis of how gas signaling molecules regulate angiogenesis is elusive. Herein, we report that hypoxic upregulation of NO synthesis in endothelial cells reprograms the transsulfuration pathway and increases H 2 S biogenesis. Furthermore, H 2 S oxidation by mitochondrial sulfide quinone oxidoreductase (SQOR) rather than downstream persulfides, synergizes with hypoxia to induce a reductive shift, limiting endothelial cell proliferation that is attenuated by dissipation of the mitochondrial NADH pool. Tumor xenografts in whole-body WB Cre SQOR fl/fl knockout mice exhibit lower mass and reduced angiogenesis compared to SQOR fl/fl controls. WB Cre SQOR fl/fl mice also exhibit reduced muscle angiogenesis following femoral artery ligation, compared to controls. Collectively, our data reveal the molecular intersections between H 2 S, O 2 and NO metabolism and identify SQOR inhibition as a metabolic vulnerability for endothelial cell proliferation and neovascularization. Highlights Hypoxic induction of •NO in endothelial cells inhibits CBS and switches CTH reaction specificity Hypoxic interruption of the canonical transsulfuration pathway promotes H 2 S synthesis Synergizing with hypoxia, SQOR deficiency induces a reductive shift in the ETC and restricts proliferationSQOR KO mice exhibit lower neovascularization in tumor xenograft and hind limb ischemia models.
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7
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Advances of H2S in Regulating Neurodegenerative Diseases by Preserving Mitochondria Function. Antioxidants (Basel) 2023; 12:antiox12030652. [PMID: 36978900 PMCID: PMC10044936 DOI: 10.3390/antiox12030652] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 02/22/2023] [Accepted: 03/03/2023] [Indexed: 03/08/2023] Open
Abstract
Neurotoxicity is induced by different toxic substances, including environmental chemicals, drugs, and pathogenic toxins, resulting in oxidative damage and neurodegeneration in mammals. The nervous system is extremely vulnerable to oxidative stress because of its high oxygen demand. Mitochondria are the main source of ATP production in the brain neuron, and oxidative stress-caused mitochondrial dysfunction is implicated in neurodegenerative diseases. H2S was initially identified as a toxic gas; however, more recently, it has been recognized as a neuromodulator as well as a neuroprotectant. Specifically, it modulates mitochondrial activity, and H2S oxidation in mitochondria produces various reactive sulfur species, thus modifying proteins through sulfhydration. This review focused on highlighting the neuron modulation role of H2S in regulating neurodegenerative diseases through anti-oxidative, anti-inflammatory, anti-apoptotic and S-sulfhydration, and emphasized the importance of H2S as a therapeutic molecule for neurological diseases.
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8
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Ruiz-Rodado V, Dowdy T, Lita A, Kramp T, Zhang M, Jung J, Dios-Esponera A, Zhang L, Herold-Mende CC, Camphausen K, Gilbert MR, Larion M. Cysteine is a limiting factor for glioma proliferation and survival. Mol Oncol 2021; 16:1777-1794. [PMID: 34856072 PMCID: PMC9067152 DOI: 10.1002/1878-0261.13148] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 10/25/2021] [Accepted: 11/30/2021] [Indexed: 11/06/2022] Open
Abstract
Nutritional intervention is becoming more prevalent as adjuvant therapy for many cancers in view of the tumor dependence on external sources for some nutrients. However, little is known about the mechanisms that make cancer cells require certain nutrients from the microenvironment. Herein, we report the dependence of glioma cells on exogenous cysteine/cystine, despite this amino acid being nonessential. Using several 13C‐tracers and analysis of cystathionine synthase and cystathioninase levels, we revealed that glioma cells were not able to support glutathione synthesis through the transsulfuration pathway, which allows methionine to be converted to cysteine in cysteine/cystine‐deprived conditions. Therefore, we explored the nutritional deprivation in a mouse model of glioma. Animals subjected to a cysteine/cystine‐free diet survived longer, although this increase did not attain statistical significance, with concomitant reductions in plasma glutathione and cysteine levels. At the end point, however, tumors displayed the ability to synthesize glutathione, even though higher levels of oxidative stress were detected. We observed a compensation from the nutritional intervention revealed as the recovery of cysteine‐related metabolite levels in plasma. Our study highlights a time window where cysteine deprivation can be exploited for additional therapeutic strategies.
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Affiliation(s)
- Victor Ruiz-Rodado
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda
| | - Tyrone Dowdy
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda
| | - Adrian Lita
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda
| | - Tamalee Kramp
- Radiation Oncology Branch, Center for Cancer Research, National Institutes of Health, Bethesda
| | - Meili Zhang
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda
| | - Jinkyu Jung
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda
| | | | - Lumin Zhang
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda
| | - Christel C Herold-Mende
- Division of Neurosurgical Research, Department of Neurosurgery, University Hospital Heidelberg, Heidelberg, Germany
| | - Kevin Camphausen
- Radiation Oncology Branch, Center for Cancer Research, National Institutes of Health, Bethesda
| | - Mark R Gilbert
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda
| | - Mioara Larion
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda
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9
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Brütting C, Hildebrand P, Brandsch C, Stangl GI. Ability of dietary factors to affect homocysteine levels in mice: a review. Nutr Metab (Lond) 2021; 18:68. [PMID: 34193183 PMCID: PMC8243555 DOI: 10.1186/s12986-021-00594-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 06/14/2021] [Indexed: 01/10/2023] Open
Abstract
Homocysteine is associated with several diseases, and a series of dietary factors are known to modulate homocysteine levels. As mice are often used as model organisms to study the effects of dietary hyperhomocysteinemia, we collected data about concentrations of vitamin B12, vitamin B6, folate, methionine, cystine, and choline in mouse diets and the associated plasma/serum homocysteine levels. In addition, we more closely examined the composition of the control diet, the impact of the mouse strain, sex and age, and the duration of the dietary intervention on homocysteine levels. In total, 113 out of 1103 reviewed articles met the inclusion criteria. In the experimental and control diets, homocysteine levels varied from 0.1 to 280 µmol/l. We found negative correlations between dietary vitamin B12 (rho = − 0.125; p < 0.05), vitamin B6 (rho = − 0.191; p < 0.01) and folate (rho = − 0.395; p < 0.001) and circulating levels of homocysteine. In contrast, a positive correlation was observed between dietary methionine and homocysteine (methionine: rho = 0.146; p < 0.05). No significant correlations were found for cystine or choline and homocysteine levels. In addition, there was no correlation between the duration of the experimental diets and homocysteine levels. More importantly, the data showed that homocysteine levels varied widely in mice fed control diets as well. When comparing control diets with similar nutrient concentrations (AIN-based), there were significant differences in homocysteine levels caused by the strain (ANOVA, p < 0.05) and age of the mice at baseline (r = 0.47; p < 0.05). When comparing homocysteine levels and sex, female mice tended to have higher homocysteine levels than male mice (9.3 ± 5.9 µmol/l vs. 5.8 ± 4.5 µmol/l; p = 0.069). To conclude, diets low in vitamin B12, vitamin B6, or folate and rich in methionine are similarly effective in increasing homocysteine levels. AIN recommendations for control diets are adequate with respect to the amounts of homocysteine-modulating dietary parameters. In addition, the mouse strain and the age of mice can affect the homocysteine level.
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Affiliation(s)
- Christine Brütting
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 2, 06120, Halle (Saale), Germany.
| | - Pia Hildebrand
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 2, 06120, Halle (Saale), Germany
| | - Corinna Brandsch
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 2, 06120, Halle (Saale), Germany
| | - Gabriele I Stangl
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 2, 06120, Halle (Saale), Germany
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10
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Pedre B, Barayeu U, Ezeriņa D, Dick TP. The mechanism of action of N-acetylcysteine (NAC): The emerging role of H 2S and sulfane sulfur species. Pharmacol Ther 2021; 228:107916. [PMID: 34171332 DOI: 10.1016/j.pharmthera.2021.107916] [Citation(s) in RCA: 246] [Impact Index Per Article: 61.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/21/2021] [Accepted: 05/24/2021] [Indexed: 12/19/2022]
Abstract
Initially adopted as a mucolytic about 60 years ago, the cysteine prodrug N-acetylcysteine (NAC) is the standard of care to treat paracetamol intoxication, and is included on the World Health Organization's list of essential medicines. Additionally, NAC increasingly became the epitome of an "antioxidant". Arguably, it is the most widely used "antioxidant" in experimental cell and animal biology, as well as clinical studies. Most investigators use and test NAC with the idea that it prevents or attenuates oxidative stress. Conventionally, it is assumed that NAC acts as (i) a reductant of disulfide bonds, (ii) a scavenger of reactive oxygen species and/or (iii) a precursor for glutathione biosynthesis. While these mechanisms may apply under specific circumstances, they cannot be generalized to explain the effects of NAC in a majority of settings and situations. In most cases the mechanism of action has remained unclear and untested. In this review, we discuss the validity of conventional assumptions and the scope of a newly discovered mechanism of action, namely the conversion of NAC into hydrogen sulfide and sulfane sulfur species. The antioxidative and cytoprotective activities of per- and polysulfides may explain many of the effects that have previously been ascribed to NAC or NAC-derived glutathione.
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Affiliation(s)
- Brandán Pedre
- Division of Redox Regulation, DKFZ-ZMBH Alliance, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Uladzimir Barayeu
- Division of Redox Regulation, DKFZ-ZMBH Alliance, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Faculty of Biosciences, Heidelberg University, 69120 Heidelberg, Germany
| | - Daria Ezeriņa
- Division of Redox Regulation, DKFZ-ZMBH Alliance, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Faculty of Biosciences, Heidelberg University, 69120 Heidelberg, Germany
| | - Tobias P Dick
- Division of Redox Regulation, DKFZ-ZMBH Alliance, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Faculty of Biosciences, Heidelberg University, 69120 Heidelberg, Germany.
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11
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Poddar R. Hyperhomocysteinemia is an emerging comorbidity in ischemic stroke. Exp Neurol 2021; 336:113541. [PMID: 33278453 PMCID: PMC7856041 DOI: 10.1016/j.expneurol.2020.113541] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 11/08/2020] [Accepted: 11/30/2020] [Indexed: 12/16/2022]
Abstract
Hyperhomocysteinemia or systemic elevation of the amino acid homocysteine is a common metabolic disorder that is considered to be a risk factor for ischemic stroke. However, it is still unclear whether predisposition to hyperhomocysteinemia could contribute to the severity of stroke outcome. This review highlights the advantages and limitations of the current rodent models of hyperhomocysteinemia, describes the consequence of mild hyperhomocysteinemia on the severity of ischemic brain damage in preclinical studies and summarizes the mechanisms involved in homocysteine induced neurotoxicity. The findings provide the premise for establishing hyperhomocysteinemia as a comorbidity for ischemic stroke and should be taken into consideration while developing potential therapeutic agents for stroke treatment.
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Affiliation(s)
- Ranjana Poddar
- Department of Neurology, University of New Mexico Health Sciences Center, 1 University of New Mexico, Albuquerque, NM 87131, USA.
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12
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Portillo F, Vázquez J, Pajares MA. Protein-protein interactions involving enzymes of the mammalian methionine and homocysteine metabolism. Biochimie 2020; 173:33-47. [PMID: 32105812 DOI: 10.1016/j.biochi.2020.02.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 02/20/2020] [Indexed: 12/16/2022]
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13
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Zuhra K, Augsburger F, Majtan T, Szabo C. Cystathionine-β-Synthase: Molecular Regulation and Pharmacological Inhibition. Biomolecules 2020; 10:E697. [PMID: 32365821 PMCID: PMC7277093 DOI: 10.3390/biom10050697] [Citation(s) in RCA: 146] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 04/24/2020] [Accepted: 04/27/2020] [Indexed: 12/11/2022] Open
Abstract
Cystathionine-β-synthase (CBS), the first (and rate-limiting) enzyme in the transsulfuration pathway, is an important mammalian enzyme in health and disease. Its biochemical functions under physiological conditions include the metabolism of homocysteine (a cytotoxic molecule and cardiovascular risk factor) and the generation of hydrogen sulfide (H2S), a gaseous biological mediator with multiple regulatory roles in the vascular, nervous, and immune system. CBS is up-regulated in several diseases, including Down syndrome and many forms of cancer; in these conditions, the preclinical data indicate that inhibition or inactivation of CBS exerts beneficial effects. This article overviews the current information on the expression, tissue distribution, physiological roles, and biochemistry of CBS, followed by a comprehensive overview of direct and indirect approaches to inhibit the enzyme. Among the small-molecule CBS inhibitors, the review highlights the specificity and selectivity problems related to many of the commonly used "CBS inhibitors" (e.g., aminooxyacetic acid) and provides a comprehensive review of their pharmacological actions under physiological conditions and in various disease models.
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Affiliation(s)
- Karim Zuhra
- Chair of Pharmacology, Section of Medicine, University of Fribourg, 1702 Fribourg, Switzerland; (K.Z.); (F.A.)
| | - Fiona Augsburger
- Chair of Pharmacology, Section of Medicine, University of Fribourg, 1702 Fribourg, Switzerland; (K.Z.); (F.A.)
| | - Tomas Majtan
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA;
| | - Csaba Szabo
- Chair of Pharmacology, Section of Medicine, University of Fribourg, 1702 Fribourg, Switzerland; (K.Z.); (F.A.)
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14
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Yadav PK, Vitvitsky V, Carballal S, Seravalli J, Banerjee R. Thioredoxin regulates human mercaptopyruvate sulfurtransferase at physiologically-relevant concentrations. J Biol Chem 2020; 295:6299-6311. [PMID: 32179647 DOI: 10.1074/jbc.ra120.012616] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 03/13/2020] [Indexed: 11/06/2022] Open
Abstract
3-Mercaptopyruvate sulfur transferase (MPST) catalyzes the desulfuration of 3-mercaptopyruvate (3-MP) and transfers sulfane sulfur from an enzyme-bound persulfide intermediate to thiophilic acceptors such as thioredoxin and cysteine. Hydrogen sulfide (H2S), a signaling molecule implicated in many physiological processes, can be released from the persulfide product of the MPST reaction. Two splice variants of MPST, differing by 20 amino acids at the N terminus, give rise to the cytosolic MPST1 and mitochondrial MPST2 isoforms. Here, we characterized the poorly-studied MPST1 variant and demonstrated that substitutions in its Ser-His-Asp triad, proposed to serve a general acid-base role, minimally affect catalytic activity. We estimated the 3-MP concentration in murine liver, kidney, and brain tissues, finding that it ranges from 0.4 μmol·kg-1 in brain to 1.4 μmol·kg-1 in kidney. We also show that N-acetylcysteine, a widely-used antioxidant, is a poor substrate for MPST and is unlikely to function as a thiophilic acceptor. Thioredoxin exhibits substrate inhibition, increasing the KM for 3-MP ∼15-fold compared with other sulfur acceptors. Kinetic simulations at physiologically-relevant substrate concentrations predicted that the proportion of sulfur transfer to thioredoxin increases ∼3.5-fold as its concentration decreases from 10 to 1 μm, whereas the total MPST reaction rate increases ∼7-fold. The simulations also predicted that cysteine is a quantitatively-significant sulfane sulfur acceptor, revealing MPST's potential to generate low-molecular-weight persulfides. We conclude that the MPST1 and MPST2 isoforms are kinetically indistinguishable and that thioredoxin modulates the MPST-catalyzed reaction in a physiologically-relevant concentration range.
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Affiliation(s)
- Pramod Kumar Yadav
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600
| | - Victor Vitvitsky
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600
| | - Sebastián Carballal
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600.,Departamento de Bioquímica, Facultad de Medicina and Centro de Investigaciones Biomédicas (CEINBIO), Universidad de la República, Montevideo 11800, Uruguay
| | - Javier Seravalli
- Department of Biochemistry and the Redox Biology Center, University of Nebraska, Lincoln, Nebraska 68588
| | - Ruma Banerjee
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600
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15
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Saini V, Chinta KC, Reddy VP, Glasgow JN, Stein A, Lamprecht DA, Rahman MA, Mackenzie JS, Truebody BE, Adamson JH, Kunota TTR, Bailey SM, Moellering DR, Lancaster JR, Steyn AJC. Hydrogen sulfide stimulates Mycobacterium tuberculosis respiration, growth and pathogenesis. Nat Commun 2020; 11:557. [PMID: 31992699 PMCID: PMC6987094 DOI: 10.1038/s41467-019-14132-y] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 12/13/2019] [Indexed: 01/23/2023] Open
Abstract
Hydrogen sulfide (H2S) is involved in numerous pathophysiological processes and shares overlapping functions with CO and •NO. However, the importance of host-derived H2S in microbial pathogenesis is unknown. Here we show that Mtb-infected mice deficient in the H2S-producing enzyme cystathionine β-synthase (CBS) survive longer with reduced organ burden, and that pharmacological inhibition of CBS reduces Mtb bacillary load in mice. High-resolution respirometry, transcriptomics and mass spectrometry establish that H2S stimulates Mtb respiration and bioenergetics predominantly via cytochrome bd oxidase, and that H2S reverses •NO-mediated inhibition of Mtb respiration. Further, exposure of Mtb to H2S regulates genes involved in sulfur and copper metabolism and the Dos regulon. Our results indicate that Mtb exploits host-derived H2S to promote growth and disease, and suggest that host-directed therapies targeting H2S production may be potentially useful for the management of tuberculosis and other microbial infections. The importance of host-produced hydrogen sulfide (H2S) in microbial pathogenesis is poorly understood. Here, Saini et al. show that H2S alters Mycobacterium tuberculosis (Mtb) central metabolism, stimulates respiration to promote growth and TB disease, and upregulates the Dos regulon.
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Affiliation(s)
- Vikram Saini
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA.,Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL, USA.,Laboratory of Infection Biology and Translational Research, Department of Biotechnology, All India Institute of Medical Sciences, New Delhi, India
| | - Krishna C Chinta
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Vineel P Reddy
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Joel N Glasgow
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Asaf Stein
- Department of Environment Health Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Dirk A Lamprecht
- Africa Health Research Institute, Durban, South Africa.,Janssen Infectious Diseases and Vaccines, Janssen Pharmaceutica NV, Beerse, Belgium
| | | | | | | | | | | | - Shannon M Bailey
- Department of Environment Health Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Douglas R Moellering
- Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jack R Lancaster
- Departments of Pharmacology and Chemical Biology, Medicine, and Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Adrie J C Steyn
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA. .,Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL, USA. .,Africa Health Research Institute, Durban, South Africa. .,Center for AIDS Research, University of Alabama at Birmingham, Birmingham, AL, USA.
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16
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Koohpeyma H, Goudarzi I, Elahdadi Salmani M, Lashkarbolouki T, Shabani M. Folic Acid Protects Rat Cerebellum Against Oxidative Damage Caused by Homocysteine: the Expression of Bcl-2, Bax, and Caspase-3 Apoptotic Genes. Neurotox Res 2019; 37:564-577. [PMID: 31721048 DOI: 10.1007/s12640-019-00119-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 09/03/2019] [Accepted: 09/25/2019] [Indexed: 01/23/2023]
Abstract
There is evidence that oxidative stress involves in homocysteine-induced pathogenesis. Considering the antioxidative properties of folic acid and its involvement as a cofactor for methionine synthase (MS) in the homocysteine-methionine cycle, the aim of this study was to evaluate the mechanism associated with homocysteine-induced toxicity and its prevention with folic acid supplementation. Male rat pups were divided into four groups including control, homocysteine (Hcy), Hcy + folic acid and folic acid groups. The Hcy group received Hcy 0.3-0.6 μmol/g body weight, while Hcy + folic acid group received folic acid orally as 0.011 μmol/g body weight along with Hcy on a postnatal day (PD) 4 until 25. The reduced and oxidized glutathione (GSH and GSSG) levels, GSH/GSSG ratio, protein carbonyl content, cystathionine β synthase (CBS), and MS activities in the cerebellum were measured 25 days after birth. Levels of malondialdehyde (MDA), marker of lipid peroxidation were measured. Also, Bcl2, Bax, and caspase-3 expression levels were measured by real-time quantitative PCR. Furthermore, caspase-3 protein level assay was performed by the ELISA test. Results indicated that Hcy administration could promote both lipid and protein oxidation, which was associated with increased amounts of caspase-3 mRNA and protein levels and Bax mRNA expression level in this group. Cerebellar MS, CBS enzyme activity, GSH, GSSG, and GSH/GSH ratio did not change following Hcy administration. Folic acid significantly reduced MDA level, protein carbonyl content, Bax, the caspase-3 mRNA, and protein expression levels in the cerebellum of Hcy-treated group. Moreover, cerebellar MS, CBS enzyme activity, GSH, and GSH/GSH ratio increased following folic acid treatment. We conclude that Hcy might cause apoptosis in the cerebellum. We suggest that folic acid, in addition of having antioxidant properties, can protect cerebellum against homocysteine-mediated neurotoxicity via modulating the expression of proteins that are contributed in regulation of apoptosis in the rat's cerebellum.
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Affiliation(s)
| | - Iran Goudarzi
- School of Biology, Damghan University, Damghan, 3671641167, Iran.
| | | | | | - Mohammad Shabani
- Neuroscience Research Center, Kerman University of Medical Sciences, Kerman, Iran
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17
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Combs JA, DeNicola GM. The Non-Essential Amino Acid Cysteine Becomes Essential for Tumor Proliferation and Survival. Cancers (Basel) 2019; 11:cancers11050678. [PMID: 31100816 PMCID: PMC6562400 DOI: 10.3390/cancers11050678] [Citation(s) in RCA: 195] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 05/13/2019] [Accepted: 05/14/2019] [Indexed: 02/07/2023] Open
Abstract
The non-essential amino acid cysteine is used within cells for multiple processes that rely on the chemistry of its thiol group. Under physiological conditions, many non-transformed tissues rely on glutathione, circulating cysteine, and the de novo cysteine synthesis (transsulfuration) pathway as sources of intracellular cysteine to support cellular processes. In contrast, many cancers require exogeneous cystine for proliferation and viability. Herein, we review how the cystine transporter, xCT, and exogenous cystine fuel cancer cell proliferation and the mechanisms that regulate xCT expression and activity. Further, we discuss the potential contribution of additional sources of cysteine to the cysteine pool and what is known about the essentiality of these processes in cancer cells. Finally, we discuss whether cyst(e)ine dependency and associated metabolic alterations represent therapeutically targetable metabolic vulnerabilities.
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Affiliation(s)
- Joseph A Combs
- Department of Cancer Physiology, H. Lee Moffitt Cancer Center, Tampa, FL 33612, USA.
| | - Gina M DeNicola
- Department of Cancer Physiology, H. Lee Moffitt Cancer Center, Tampa, FL 33612, USA.
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18
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Kohl JB, Mellis A, Schwarz G. Homeostatic impact of sulfite and hydrogen sulfide on cysteine catabolism. Br J Pharmacol 2019; 176:554-570. [PMID: 30088670 PMCID: PMC6346071 DOI: 10.1111/bph.14464] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 06/22/2018] [Accepted: 07/02/2018] [Indexed: 12/30/2022] Open
Abstract
Cysteine is one of the two key sulfur-containing amino acids with important functions in redox homeostasis, protein functionality and metabolism. Cysteine is taken up by mammals via their diet and can also be derived from methionine via the transsulfuration pathway. The cellular concentration of cysteine is kept within a narrow range by controlling its synthesis and degradation. There are two pathways for the catabolism of cysteine leading to sulfate, taurine and thiosulfate as terminal products. The oxidative pathway produces taurine and sulfate, while the H2 S pathway involves different enzymatic reactions leading to the formation and clearance of H2 S, an important signalling molecule in mammals, resulting in thiosulfate and sulfate. Sulfite is a common intermediate in both catabolic pathways. Sulfite is considered as cytotoxic and produces neurotoxic S-sulfonates. As a result, a deficiency in the terminal steps of cysteine or H2 S catabolism leads to severe forms of encephalopathy with the accumulation of sulfite and H2 S in the body. This review links the homeostatic regulation of both cysteine catabolic pathways to sulfite and H2 S. LINKED ARTICLES: This article is part of a themed section on Chemical Biology of Reactive Sulfur Species. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.4/issuetoc.
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Affiliation(s)
- Joshua B Kohl
- Institute of Biochemistry, Department of Chemistry and Center for Molecular Medicine CologneUniversity of CologneCologneGermany
| | - Anna‐Theresa Mellis
- Institute of Biochemistry, Department of Chemistry and Center for Molecular Medicine CologneUniversity of CologneCologneGermany
| | - Guenter Schwarz
- Institute of Biochemistry, Department of Chemistry and Center for Molecular Medicine CologneUniversity of CologneCologneGermany
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19
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Pajares MA, Pérez-Sala D. Mammalian Sulfur Amino Acid Metabolism: A Nexus Between Redox Regulation, Nutrition, Epigenetics, and Detoxification. Antioxid Redox Signal 2018; 29:408-452. [PMID: 29186975 DOI: 10.1089/ars.2017.7237] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
SIGNIFICANCE Transsulfuration allows conversion of methionine into cysteine using homocysteine (Hcy) as an intermediate. This pathway produces S-adenosylmethionine (AdoMet), a key metabolite for cell function, and provides 50% of the cysteine needed for hepatic glutathione synthesis. The route requires the intake of essential nutrients (e.g., methionine and vitamins) and is regulated by their availability. Transsulfuration presents multiple interconnections with epigenetics, adenosine triphosphate (ATP), and glutathione synthesis, polyol and pentose phosphate pathways, and detoxification that rely mostly in the exchange of substrates or products. Major hepatic diseases, rare diseases, and sensorineural disorders, among others that concur with oxidative stress, present impaired transsulfuration. Recent Advances: In contrast to the classical view, a nuclear branch of the pathway, potentiated under oxidative stress, is emerging. Several transsulfuration proteins regulate gene expression, suggesting moonlighting activities. In addition, abnormalities in Hcy metabolism link nutrition and hearing loss. CRITICAL ISSUES Knowledge about the crossregulation between pathways is mostly limited to the hepatic availability/removal of substrates and inhibitors. However, advances regarding protein-protein interactions involving oncogenes, identification of several post-translational modifications (PTMs), and putative moonlighting activities expand the potential impact of transsulfuration beyond methylations and Hcy. FUTURE DIRECTIONS Increasing the knowledge on transsulfuration outside the liver, understanding the protein-protein interaction networks involving these enzymes, the functional role of their PTMs, or the mechanisms controlling their nucleocytoplasmic shuttling may provide further insights into the pathophysiological implications of this pathway, allowing design of new therapeutic interventions. Antioxid. Redox Signal. 29, 408-452.
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Affiliation(s)
- María A Pajares
- 1 Department of Chemical and Physical Biology, Centro de Investigaciones Biológicas (CSIC) , Madrid, Spain .,2 Molecular Hepatology Group, Instituto de Investigación Sanitaria La Paz (IdiPAZ) , Madrid, Spain
| | - Dolores Pérez-Sala
- 1 Department of Chemical and Physical Biology, Centro de Investigaciones Biológicas (CSIC) , Madrid, Spain
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20
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Pal VK, Bandyopadhyay P, Singh A. Hydrogen sulfide in physiology and pathogenesis of bacteria and viruses. IUBMB Life 2018; 70:393-410. [PMID: 29601123 PMCID: PMC6029659 DOI: 10.1002/iub.1740] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 02/14/2018] [Accepted: 03/02/2018] [Indexed: 12/18/2022]
Abstract
An increasing number of studies have established hydrogen sulfide (H2S) gas as a major cytoprotectant and redox modulator. Following its discovery, H2S has been found to have pleiotropic effects on physiology and human health. H2S acts as a gasotransmitter and exerts its influence on gastrointestinal, neuronal, cardiovascular, respiratory, renal, and hepatic systems. Recent discoveries have clearly indicated the importance of H2S in regulating vasorelaxation, angiogenesis, apoptosis, ageing, and metabolism. Contrary to studies in higher organisms, the role of H2S in the pathophysiology of infectious agents such as bacteria and viruses has been less studied. Bacterial and viral infections are often accompanied by changes in the redox physiology of both the host and the pathogen. Emerging studies indicate that bacterial-derived H2S constitutes a defense system against antibiotics and oxidative stress. The H2S signaling pathway also seems to interfere with redox-based events affected on infection with viruses. This review aims to summarize recent advances on the emerging role of H2S gas in the bacterial physiology and viral infections. Such studies have opened up new research avenues exploiting H2S as a potential therapeutic intervention.
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Affiliation(s)
- Virender Kumar Pal
- Department of Microbiology and Cell Biology, Centre for Infectious Disease Research, Indian Institute of Science (IISc), Bangalore, India
| | - Parijat Bandyopadhyay
- Department of Microbiology and Cell Biology, Centre for Infectious Disease Research, Indian Institute of Science (IISc), Bangalore, India
| | - Amit Singh
- Department of Microbiology and Cell Biology, Centre for Infectious Disease Research, Indian Institute of Science (IISc), Bangalore, India
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21
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Libiad M, Motl N, Akey DL, Sakamoto N, Fearon ER, Smith JL, Banerjee R. Thiosulfate sulfurtransferase-like domain-containing 1 protein interacts with thioredoxin. J Biol Chem 2018; 293:2675-2686. [PMID: 29348167 PMCID: PMC5827441 DOI: 10.1074/jbc.ra117.000826] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 01/16/2018] [Indexed: 12/11/2022] Open
Abstract
Rhodanese domains are structural modules present in the sulfurtransferase superfamily. These domains can exist as single units, in tandem repeats, or fused to domains with other activities. Despite their prevalence across species, the specific physiological roles of most sulfurtransferases are not known. Mammalian rhodanese and mercaptopyruvate sulfurtransferase are perhaps the best-studied members of this protein superfamily and are involved in hydrogen sulfide metabolism. The relatively unstudied human thiosulfate sulfurtransferase-like domain-containing 1 (TSTD1) protein, a single-domain cytoplasmic sulfurtransferase, was also postulated to play a role in the sulfide oxidation pathway using thiosulfate to form glutathione persulfide, for subsequent processing in the mitochondrial matrix. Prior kinetic analysis of TSTD1 was performed at pH 9.2, raising questions about relevance and the proposed model for TSTD1 function. In this study, we report a 1.04 Å resolution crystal structure of human TSTD1, which displays an exposed active site that is distinct from that of rhodanese and mercaptopyruvate sulfurtransferase. Kinetic studies with a combination of sulfur donors and acceptors reveal that TSTD1 exhibits a low Km for thioredoxin as a sulfane sulfur acceptor and that it utilizes thiosulfate inefficiently as a sulfur donor. The active site exposure and its interaction with thioredoxin suggest that TSTD1 might play a role in sulfide-based signaling. The apical localization of TSTD1 in human colonic crypts, which interfaces with sulfide-releasing microbes, and the overexpression of TSTD1 in colon cancer provide potentially intriguing clues as to its role in sulfide metabolism.
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Affiliation(s)
- Marouane Libiad
- Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan 48109
| | - Nicole Motl
- Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan 48109
| | - David L Akey
- Life Sciences Institute, University of Michigan Medical Center, Ann Arbor, Michigan 48109
| | - Naoya Sakamoto
- Department of Molecular Pathology, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Eric R Fearon
- Departments of Internal Medicine, Human Genetics, and Pathology, University of Michigan Medical Center, Ann Arbor, Michigan 48109
| | - Janet L Smith
- Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan 48109; Life Sciences Institute, University of Michigan Medical Center, Ann Arbor, Michigan 48109
| | - Ruma Banerjee
- Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan 48109.
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22
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Prabhudesai S, Koceja C, Dey A, Eisa-Beygi S, Leigh NR, Bhattacharya R, Mukherjee P, Ramchandran R. Cystathionine β-Synthase Is Necessary for Axis Development in Vivo. Front Cell Dev Biol 2018; 6:14. [PMID: 29503817 PMCID: PMC5820354 DOI: 10.3389/fcell.2018.00014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 01/30/2018] [Indexed: 12/20/2022] Open
Abstract
The cystathionine ß-synthase (CBS) is a critical enzyme in the transsulfuration pathway and is responsible for the synthesis of cystathionine from serine and homocysteine. Cystathionine is a precursor to amino acid cysteine. CBS is also responsible for generation of hydrogen sulfide (H2S) from cysteine. Mutation in CBS enzyme causes homocysteine levels to rise, and gives rise to a condition called hyperhomocysteinuria. To date, numerous mouse knockout models for CBS enzyme has been generated, which show panoply of defects, reflecting the importance of this enzyme in development. In zebrafish, we and others have identified two orthologs of cbs, which we call cbsa and cbsb. Previous gene knockdown studies in zebrafish have reported a function for cbsb ortholog in maintaining ion homeostasis in developing embryos. However, its role in maintaining H2S homeostasis in embryos is unknown. Here, we have performed RNA analysis in whole zebrafish embryos that showed a wide expression pattern for cbsa and cbsb primarily along the embryonic axis of the developing embryo. Loss-of-function analysis using a combination of approaches which include splice morpholinos and CRISPR/Cas9 genomic engineering show evidence that cbsb ortholog is responsible for anterior-posterior axis development, and cbsa function is redundant. Cbsb loss of function fish embryos show shortened and bent axis, along with less H2S and more homocysteine, effects resulting from loss of Cbsb. Using a chemical biology approach, we rescued the axis defects with betaine, a compound known to reduce homocysteine levels in plasma, and GYY4137, a long term H2S donor. These results collectively argue that cells along the axis of a developing embryo are sensitive to changes in homocysteine and H2S levels, pathways that are controlled by Cbsb, and thus is essential for development.
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Affiliation(s)
- Shubhangi Prabhudesai
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Chris Koceja
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Anindya Dey
- Department of Obstetrics and Gynecology, University of Oklahoma Health Science Center, Oklahoma City, OK, United States
| | - Shahram Eisa-Beygi
- Pediatrics Radiology, Developmental Vascular Biology Program, Children's Research Institute, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Noah R. Leigh
- Milwaukee Health Department, City of Milwaukee, Milwaukee, WI, United States
| | - Resham Bhattacharya
- Department of Obstetrics and Gynecology, University of Oklahoma Health Science Center, Oklahoma City, OK, United States
- Peggy and Charles Stephenson Cancer Center, University of Oklahoma Health Science Center, Oklahoma City, OK, United States
| | - Priyabrata Mukherjee
- Department of Obstetrics and Gynecology, University of Oklahoma Health Science Center, Oklahoma City, OK, United States
- Peggy and Charles Stephenson Cancer Center, University of Oklahoma Health Science Center, Oklahoma City, OK, United States
- Department of Pathology, University of Oklahoma Health Science Center, Oklahoma City, OK, United States
- Department of Cell Biology, University of Oklahoma Health Science Center, Oklahoma City, OK, United States
| | - Ramani Ramchandran
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, United States
- Pediatrics Radiology, Developmental Vascular Biology Program, Children's Research Institute, Medical College of Wisconsin, Milwaukee, WI, United States
- Obstetrics and Gynecology, Medical College of Wisconsin, Milwaukee, WI, United States
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23
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Filipovic MR, Zivanovic J, Alvarez B, Banerjee R. Chemical Biology of H 2S Signaling through Persulfidation. Chem Rev 2018; 118:1253-1337. [PMID: 29112440 PMCID: PMC6029264 DOI: 10.1021/acs.chemrev.7b00205] [Citation(s) in RCA: 692] [Impact Index Per Article: 98.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Signaling by H2S is proposed to occur via persulfidation, a posttranslational modification of cysteine residues (RSH) to persulfides (RSSH). Persulfidation provides a framework for understanding the physiological and pharmacological effects of H2S. Due to the inherent instability of persulfides, their chemistry is understudied. In this review, we discuss the biologically relevant chemistry of H2S and the enzymatic routes for its production and oxidation. We cover the chemical biology of persulfides and the chemical probes for detecting them. We conclude by discussing the roles ascribed to protein persulfidation in cell signaling pathways.
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Affiliation(s)
- Milos R. Filipovic
- Univeristy of Bordeaux, IBGC, UMR 5095, F-33077 Bordeaux, France
- CNRS, IBGC, UMR 5095, F-33077 Bordeaux, France
| | - Jasmina Zivanovic
- Univeristy of Bordeaux, IBGC, UMR 5095, F-33077 Bordeaux, France
- CNRS, IBGC, UMR 5095, F-33077 Bordeaux, France
| | - Beatriz Alvarez
- Laboratorio de Enzimología, Facultad de Ciencias and Center for Free Radical and Biomedical Research, Universidad de la Republica, 11400 Montevideo, Uruguay
| | - Ruma Banerjee
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600, United States
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24
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Glutathione and Transsulfuration in Alcohol-Associated Tissue Injury and Carcinogenesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1032:37-53. [PMID: 30362089 DOI: 10.1007/978-3-319-98788-0_3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Glutathione (GSH) is the most abundant non-protein thiol, attaining cellular concentrations in the millimolar range. GSH functions to protect cells against endogenous and exogenous electrophiles. In addition, GSH serves as a cofactor for the GSH peroxidase family of enzymes which metabolize H2O2 as well as lipid peroxides. Through the action of glutathione S-transferase family of enzymes, GSH is conjugated to a variety of electrophilic endogenous compounds and exogenous chemicals, and thereby facilitates their efficient and safe elimination. Through the transsulfuration pathway, GSH biosynthesis is metabolically linked with cellular methylation, which is pivotal for epigenetic gene regulation. Accumulating evidence suggests that the underlying mechanisms of alcohol-associated tissue injury and carcinogenesis involve: (i) generation of the electrophilic metabolite acetaldehyde, (ii) induction of CYP2E1 leading to the formation of reactive oxygen species and pro-carcinogen activation, and (iii) nutritional deficiencies, such as methyl groups, resulting in enhanced susceptibility to cancer development. In this context, clinical and experimental investigations suggest an intimate involvement of GSH and related enzymes in the development of alcohol-induced pathological conditions. The aim of this review is to provide an overview of the GSH biosynthesis, cellular transsulfuration/transmethylation pathways, and their implications in the pathogenesis and treatment of alcohol-related disease and cancer.
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25
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Majtan T, Hůlková H, Park I, Krijt J, Kožich V, Bublil EM, Kraus JP. Enzyme replacement prevents neonatal death, liver damage, and osteoporosis in murine homocystinuria. FASEB J 2017; 31:5495-5506. [PMID: 28821635 DOI: 10.1096/fj.201700565r] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 07/31/2017] [Indexed: 11/11/2022]
Abstract
Classical homocystinuria (HCU) is an inborn error of sulfur amino acid metabolism caused by deficient activity of cystathionine β-synthase (CBS), resulting in an accumulation of homocysteine and a concomitant decrease of cystathionine and cysteine in blood and tissues. In mice, the complete lack of CBS is neonatally lethal. In this study, newborn CBS-knockout (KO) mice were treated with recombinant polyethyleneglycolylated human truncated CBS (PEG-CBS). Full survival of the treated KO mice, along with a positive impact on metabolite levels in plasma, liver, brain, and kidneys, was observed. The PEG-CBS treatment prevented an otherwise fatal liver disease characterized by steatosis, death of hepatocytes, and ultrastructural abnormalities of endoplasmic reticulum and mitochondria. Furthermore, treatment of the KO mice for 5 mo maintained the plasma metabolite balance and completely prevented osteoporosis and changes in body composition that characterize both the KO model and human patients. These findings argue that early treatment of patients with HCU with PEG-CBS may prevent clinical symptoms of the disease possibly without the need of dietary protein restriction.-Majtan, T., Hůlková, H., Park, I., Krijt, J., Kožich, V., Bublil, E. M., Kraus, J. P. Enzyme replacement prevents neonatal death, liver damage, and osteoporosis in murine homocystinuria.
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Affiliation(s)
- Tomas Majtan
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado, USA;
| | - Helena Hůlková
- Institute of Inherited Metabolic Disorders, Charles University-First Faculty of Medicine and General University Hospital, Prague, Czech Republic.,Institute of Pathology, Charles University-First Faculty of Medicine and General University Hospital, Prague, Czech Republic; and
| | - Insun Park
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Jakub Krijt
- Institute of Inherited Metabolic Disorders, Charles University-First Faculty of Medicine and General University Hospital, Prague, Czech Republic
| | - Viktor Kožich
- Institute of Inherited Metabolic Disorders, Charles University-First Faculty of Medicine and General University Hospital, Prague, Czech Republic
| | - Erez M Bublil
- Orphan Technologies Limited, Rapperswil, Switzerland
| | - Jan P Kraus
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado, USA;
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Landry AP, Ballou DP, Banerjee R. H 2S oxidation by nanodisc-embedded human sulfide quinone oxidoreductase. J Biol Chem 2017; 292:11641-11649. [PMID: 28512131 DOI: 10.1074/jbc.m117.788547] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 05/05/2017] [Indexed: 01/09/2023] Open
Abstract
Buildup of hydrogen sulfide (H2S), which functions as a signaling molecule but is toxic at high concentrations, is averted by its efficient oxidation by the mitochondrial sulfide oxidation pathway. The first step in this pathway is catalyzed by a flavoprotein, sulfide quinone oxidoreductase (SQR), which converts H2S to a persulfide and transfers electrons to coenzyme Q via a flavin cofactor. All previous studies on human SQR have used detergent-solubilized protein. Here, we embedded human SQR in nanodiscs (ndSQR) and studied highly homogenous preparations by steady-state and rapid-kinetics techniques. ndSQR exhibited higher catalytic rates in its membranous environment than in its solubilized state. Stopped-flow spectroscopic data revealed that transfer of the sulfane sulfur from an SQR-bound cysteine persulfide intermediate to a small-molecule acceptor is the rate-limiting step. The physiological acceptor of sulfane sulfur from SQR has been the subject of controversy; we report that the kinetic analysis of ndSQR is consistent with glutathione rather than sulfite being the predominant acceptor at physiologically relevant concentrations of the respective metabolites. The identity of the acceptor has an important bearing on how the sulfide oxidation pathway is organized. Our data are more consistent with the reaction sequence for sulfide oxidation being: H2S → glutathione persulfide → sulfite → sulfate, than with a more convoluted route that would result if sulfite were the primary acceptor of sulfane sulfur. In summary, nanodisc-incorporated human SQR exhibits enhanced catalytic performance, and pre-steady-state kinetics characterization of the complete SQR catalytic cycle indicates that GSH serves as the physiologically relevant sulfur acceptor.
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Affiliation(s)
- Aaron P Landry
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - David P Ballou
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Ruma Banerjee
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109.
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27
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Rose P, Moore PK, Zhu YZ. H 2S biosynthesis and catabolism: new insights from molecular studies. Cell Mol Life Sci 2016; 74:1391-1412. [PMID: 27844098 PMCID: PMC5357297 DOI: 10.1007/s00018-016-2406-8] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 10/07/2016] [Accepted: 11/01/2016] [Indexed: 02/06/2023]
Abstract
Hydrogen sulfide (H2S) has profound biological effects within living organisms and is now increasingly being considered alongside other gaseous signalling molecules, such as nitric oxide (NO) and carbon monoxide (CO). Conventional use of pharmacological and molecular approaches has spawned a rapidly growing research field that has identified H2S as playing a functional role in cell-signalling and post-translational modifications. Recently, a number of laboratories have reported the use of siRNA methodologies and genetic mouse models to mimic the loss of function of genes involved in the biosynthesis and degradation of H2S within tissues. Studies utilising these systems are revealing new insights into the biology of H2S within the cardiovascular system, inflammatory disease, and in cell signalling. In light of this work, the current review will describe recent advances in H2S research made possible by the use of molecular approaches and genetic mouse models with perturbed capacities to generate or detoxify physiological levels of H2S gas within tissues.
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Affiliation(s)
- Peter Rose
- School of Life Science, University of Lincoln, Brayford Pool, Lincoln, Lincolnshire, LN6 7TS, UK. .,State Key Laboratory of Quality Research in Chinese Medicine and School of Pharmacy, Macau University of Science and Technology, Macau, China.
| | - Philip K Moore
- Department of Pharmacology, National University of Singapore, Lee Kong Chian Wing, UHL #05-02R, 21 Lower Kent Ridge Road, Singapore, 119077, Singapore
| | - Yi Zhun Zhu
- State Key Laboratory of Quality Research in Chinese Medicine and School of Pharmacy, Macau University of Science and Technology, Macau, China
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ROCCHICCIOLI M, MOSCHINI R, CAPPIELLO L, BALESTRI F, CAPPIELLO M, MURA U, DEL-CORSO A. Colorimetric Coupled Enzyme Assay for Cystathionine β-Synthase. ANAL SCI 2016; 32:901-6. [DOI: 10.2116/analsci.32.901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
| | | | - Laura CAPPIELLO
- University of Pisa, Department of Biology, Biochemistry Unit
| | | | - Mario CAPPIELLO
- University of Pisa, Department of Biology, Biochemistry Unit
| | - Umberto MURA
- University of Pisa, Department of Biology, Biochemistry Unit
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29
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Yadav PK, Martinov M, Vitvitsky V, Seravalli J, Wedmann R, Filipovic MR, Banerjee R. Biosynthesis and Reactivity of Cysteine Persulfides in Signaling. J Am Chem Soc 2015; 138:289-99. [PMID: 26667407 DOI: 10.1021/jacs.5b10494] [Citation(s) in RCA: 196] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Hydrogen sulfide (H2S) elicits pleiotropic physiological effects ranging from modulation of cardiovascular to CNS functions. A dominant method for transmission of sulfide-based signals is via posttranslational modification of reactive cysteine thiols to persulfides. However, the source of the persulfide donor and whether its relationship to H2S is as a product or precursor is controversial. The transsulfuration pathway enzymes can synthesize cysteine persulfide (Cys-SSH) from cystine and H2S from cysteine and/or homocysteine. Recently, Cys-SSH was proposed as the primary product of the transsulfuration pathway with H2S representing a decomposition product of Cys-SSH. Our detailed kinetic analyses demonstrate a robust capacity for Cys-SSH production by the human transsulfuration pathway enzymes, cystathionine beta-synthase and γ-cystathionase (CSE) and for homocysteine persulfide synthesis from homocystine by CSE only. However, in the reducing cytoplasmic milieu where the concentration of reduced thiols is significantly higher than of disulfides, substrate level regulation favors the synthesis of H2S over persulfides. Mathematical modeling at physiologically relevant hepatic substrate concentrations predicts that H2S rather than Cys-SSH is the primary product of the transsulfuration enzymes with CSE being the dominant producer. The half-life of the metastable Cys-SSH product is short and decomposition leads to a mixture of polysulfides (Cys-S-(S)n-S-Cys). These in vitro data, together with the intrinsic reactivity of Cys-SSH for cysteinyl versus sulfur transfer, are consistent with the absence of an observable increase in protein persulfidation in cells in response to exogenous cystine and evidence for the formation of polysulfides under these conditions.
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Affiliation(s)
- Pramod K Yadav
- Department of Biological Chemistry, University of Michigan Medical School , Ann Arbor, Michigan 48109-0600, United States
| | - Michael Martinov
- Center for Theoretical Problems of Physicochemical Pharmacology, Russian Academy of Sciences , Moscow 119991, Russia
| | - Victor Vitvitsky
- Department of Biological Chemistry, University of Michigan Medical School , Ann Arbor, Michigan 48109-0600, United States
| | - Javier Seravalli
- Department of Biochemistry and the Redox Biology Center, University of Nebraska-Lincoln , Lincoln, Nebraska 68588, United States
| | - Rudolf Wedmann
- Department of Chemistry and Pharmacy, Friedrich-Alexander University of Erlangen-Nuremberg , 91058 Erlangen, Germany
| | - Milos R Filipovic
- Department of Chemistry and Pharmacy, Friedrich-Alexander University of Erlangen-Nuremberg , 91058 Erlangen, Germany
| | - Ruma Banerjee
- Department of Biological Chemistry, University of Michigan Medical School , Ann Arbor, Michigan 48109-0600, United States
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30
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Murray TVA, Dong X, Sawyer GJ, Caldwell A, Halket J, Sherwood R, Quaglia A, Dew T, Anilkumar N, Burr S, Mistry RK, Martin D, Schröder K, Brandes RP, Hughes RD, Shah AM, Brewer AC. NADPH oxidase 4 regulates homocysteine metabolism and protects against acetaminophen-induced liver damage in mice. Free Radic Biol Med 2015; 89:918-30. [PMID: 26472193 PMCID: PMC4698376 DOI: 10.1016/j.freeradbiomed.2015.09.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 09/02/2015] [Accepted: 09/04/2015] [Indexed: 01/08/2023]
Abstract
Glutathione is the major intracellular redox buffer in the liver and is critical for hepatic detoxification of xenobiotics and other environmental toxins. Hepatic glutathione is also a major systemic store for other organs and thus impacts on pathologies such as Alzheimer's disease, Sickle Cell Anaemia and chronic diseases associated with aging. Glutathione levels are determined in part by the availability of cysteine, generated from homocysteine through the transsulfuration pathway. The partitioning of homocysteine between remethylation and transsulfuration pathways is known to be subject to redox-dependent regulation, but the underlying mechanisms are not known. An association between plasma Hcy and a single nucleotide polymorphism within the NADPH oxidase 4 locus led us to investigate the involvement of this reactive oxygen species- generating enzyme in homocysteine metabolism. Here we demonstrate that NADPH oxidase 4 ablation in mice results in increased flux of homocysteine through the betaine-dependent remethylation pathway to methionine, catalysed by betaine-homocysteine-methyltransferase within the liver. As a consequence NADPH oxidase 4-null mice display significantly lowered plasma homocysteine and the flux of homocysteine through the transsulfuration pathway is reduced, resulting in lower hepatic cysteine and glutathione levels. Mice deficient in NADPH oxidase 4 had markedly increased susceptibility to acetaminophen-induced hepatic injury which could be corrected by administration of N-acetyl cysteine. We thus conclude that under physiological conditions, NADPH oxidase 4-derived reactive oxygen species is a regulator of the partitioning of the metabolic flux of homocysteine, which impacts upon hepatic cysteine and glutathione levels and thereby upon defence against environmental toxins.
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Affiliation(s)
- Thomas V A Murray
- Cardiovascular Division, King's College London, 125 Coldharbour Lane, London E5 0AD
| | - Xuebin Dong
- Cardiovascular Division, King's College London, 125 Coldharbour Lane, London E5 0AD
| | - Greta J Sawyer
- Cardiovascular Division, King's College London, 125 Coldharbour Lane, London E5 0AD
| | - Anna Caldwell
- Mass Spectrometry Facility, King's College London, FWB, 150 Stamford Street London E1 9NH
| | - John Halket
- Mass Spectrometry Facility, King's College London, FWB, 150 Stamford Street London E1 9NH
| | - Roy Sherwood
- NHS Foundation Trust, King's College Hospital, Denmark Hill, London SE5 9RS
| | - Alberto Quaglia
- Institute of Liver Studies, King's College London, Denmark Hill, London SE5 9RS
| | - Tracy Dew
- NHS Foundation Trust, King's College Hospital, Denmark Hill, London SE5 9RS
| | - Narayana Anilkumar
- Cardiovascular Division, King's College London, 125 Coldharbour Lane, London E5 0AD
| | - Simon Burr
- Cardiovascular Division, King's College London, 125 Coldharbour Lane, London E5 0AD
| | - Rajesh K Mistry
- Cardiovascular Division, King's College London, 125 Coldharbour Lane, London E5 0AD
| | - Daniel Martin
- Cardiovascular Division, King's College London, 125 Coldharbour Lane, London E5 0AD
| | - Katrin Schröder
- Institut für Kardiovaskuläre Physiologie, Goethe-Universität, 60596 Frankfurt am Main, Germany
| | - Ralf P Brandes
- Institut für Kardiovaskuläre Physiologie, Goethe-Universität, 60596 Frankfurt am Main, Germany
| | - Robin D Hughes
- Institute of Liver Studies, King's College London, Denmark Hill, London SE5 9RS
| | - Ajay M Shah
- Cardiovascular Division, King's College London, 125 Coldharbour Lane, London E5 0AD
| | - Alison C Brewer
- Cardiovascular Division, King's College London, 125 Coldharbour Lane, London E5 0AD.
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31
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Mishanina TV, Libiad M, Banerjee R. Biogenesis of reactive sulfur species for signaling by hydrogen sulfide oxidation pathways. Nat Chem Biol 2015; 11:457-64. [PMID: 26083070 DOI: 10.1038/nchembio.1834] [Citation(s) in RCA: 444] [Impact Index Per Article: 44.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 04/24/2015] [Indexed: 12/11/2022]
Abstract
The chemical species involved in H2S signaling remain elusive despite the profound and pleiotropic physiological effects elicited by this molecule. The dominant candidate mechanism for sulfide signaling is persulfidation of target proteins. However, the relatively poor reactivity of H2S toward oxidized thiols, such as disulfides, the low concentration of disulfides in the reducing milieu of the cell and the low steady-state concentration of H2S raise questions about the plausibility of persulfide formation via reaction between an oxidized thiol and a sulfide anion or a reduced thiol and oxidized hydrogen disulfide. In contrast, sulfide oxidation pathways, considered to be primarily mechanisms for disposing of excess sulfide, generate a series of reactive sulfur species, including persulfides, polysulfides and thiosulfate, that could modify target proteins. We posit that sulfide oxidation pathways mediate sulfide signaling and that sulfurtransferases ensure target specificity.
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Affiliation(s)
- Tatiana V Mishanina
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Marouane Libiad
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Ruma Banerjee
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA
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32
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Abstract
Hydrogen sulfide (H₂S) has emerged as an important signaling molecule with beneficial effects on various cellular processes affecting, for example, cardiovascular and neurological functions. The physiological importance of H₂S is motivating efforts to develop strategies for modulating its levels. However, advancement in the field of H₂S-based therapeutics is hampered by fundamental gaps in our knowledge of how H₂S is regulated, its mechanism of action, and its molecular targets. This review provides an overview of sulfur metabolism; describes recent progress that has shed light on the mechanism of H₂S as a signaling molecule; and examines nutritional regulation of sulfur metabolism, which pertains to health and disease.
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Affiliation(s)
- Omer Kabil
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600;
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33
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Gherasim C, Ruetz M, Li Z, Hudolin S, Banerjee R. Pathogenic mutations differentially affect the catalytic activities of the human B12-processing chaperone CblC and increase futile redox cycling. J Biol Chem 2015; 290:11393-402. [PMID: 25809485 DOI: 10.1074/jbc.m115.637132] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Indexed: 11/06/2022] Open
Abstract
Human CblC catalyzes the elimination of the upper axial ligand in cobalamin or B12 derivatives entering the cell from circulation. This processing step is critical for assimilation of dietary cobalamin into the active cofactor forms that support the B12-dependent enzymes, methionine synthase and methylmalonyl-CoA mutase. Using a modified nitroreductase scaffold tailored to bind cobalamin and glutathione, CblC exhibits versatility in the mechanism by which it removes cyano versus alkyl ligands in cobalamin. In this study, we have characterized the effects of two pathogenic missense mutations at the same residue, R161G and R161Q, which are associated with early and late onset of the CblC disorder, respectively. We find that the R161Q and R161G CblC mutants display lower protein stability and decreased dealkylation but not decyanation activity, suggesting that cyanocobalamin might be therapeutically useful for patients carrying mutations at Arg-161. The mutant proteins also exhibit impaired glutathione binding. In the presence of physiologically relevant glutathione concentrations, stabilization of the cob(II)alamin derivative is observed, which occurs at the expense of increased oxidation of glutathione. Futile redox cycling, which is suppressed in wild-type human CblC, explains the reported increase in oxidative stress levels associated with the CblC disorder.
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Affiliation(s)
- Carmen Gherasim
- From the Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan 48109-0600
| | - Markus Ruetz
- From the Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan 48109-0600
| | - Zhu Li
- From the Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan 48109-0600
| | - Stephanie Hudolin
- From the Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan 48109-0600
| | - Ruma Banerjee
- From the Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan 48109-0600
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34
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Libiad M, Yadav PK, Vitvitsky V, Martinov M, Banerjee R. Organization of the human mitochondrial hydrogen sulfide oxidation pathway. J Biol Chem 2014; 289:30901-10. [PMID: 25225291 DOI: 10.1074/jbc.m114.602664] [Citation(s) in RCA: 196] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Sulfide oxidation is expected to play an important role in cellular switching between low steady-state intracellular hydrogen sulfide levels and the higher concentrations where the physiological effects are elicited. Yet despite its significance, fundamental questions regarding how the sulfide oxidation pathway is wired remain unanswered, and competing proposals exist that diverge at the very first step catalyzed by sulfide quinone oxidoreductase (SQR). We demonstrate that, in addition to sulfite, glutathione functions as a persulfide acceptor for human SQR and that rhodanese preferentially synthesizes rather than utilizes thiosulfate. The kinetic behavior of these enzymes provides compelling evidence for the flow of sulfide via SQR to glutathione persulfide, which is then partitioned to thiosulfate or sulfite. Kinetic simulations at physiologically relevant metabolite concentrations provide additional support for the organizational logic of the sulfide oxidation pathway in which glutathione persulfide is the first intermediate formed.
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Affiliation(s)
- Marouane Libiad
- From the Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan 48109-0600 and
| | - Pramod Kumar Yadav
- From the Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan 48109-0600 and
| | - Victor Vitvitsky
- From the Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan 48109-0600 and
| | - Michael Martinov
- the National Research Center for Hematology, Moscow 125167, Russia
| | - Ruma Banerjee
- From the Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, Michigan 48109-0600 and
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Kabil O, Motl N, Banerjee R. H2S and its role in redox signaling. BIOCHIMICA ET BIOPHYSICA ACTA 2014; 1844:1355-66. [PMID: 24418393 PMCID: PMC4048824 DOI: 10.1016/j.bbapap.2014.01.002] [Citation(s) in RCA: 174] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 12/19/2013] [Accepted: 01/02/2014] [Indexed: 02/08/2023]
Abstract
Hydrogen sulfide (H2S) has emerged as an important gaseous signaling molecule that is produced endogenously by enzymes in the sulfur metabolic network. H2S exerts its effects on multiple physiological processes important under both normal and pathological conditions. These functions include neuromodulation, regulation of blood pressure and cardiac function, inflammation, cellular energetics and apoptosis. Despite the recognition of its biological importance and its beneficial effects, the mechanism of H2S action and the regulation of its tissue levels remain unclear in part owing to its chemical and physical properties that render handling and analysis challenging. Furthermore, the multitude of potential H2S effects has made it difficult to dissect its signaling mechanism and to identify specific targets. In this review, we focus on H2S metabolism and provide an overview of the recent literature that sheds some light on its mechanism of action in cellular redox signaling in health and disease. This article is part of a Special Issue entitled: Thiol-Based Redox Processes.
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Affiliation(s)
- Omer Kabil
- University of Michigan Medical School, Ann Arbor, MI 48109-0600, USA
| | - Nicole Motl
- University of Michigan Medical School, Ann Arbor, MI 48109-0600, USA
| | - Ruma Banerjee
- University of Michigan Medical School, Ann Arbor, MI 48109-0600, USA.
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36
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Akahoshi N, Kamata S, Kubota M, Hishiki T, Nagahata Y, Matsuura T, Yamazaki C, Yoshida Y, Yamada H, Ishizaki Y, Suematsu M, Kasahara T, Ishii I. Neutral aminoaciduria in cystathionine β-synthase-deficient mice, an animal model of homocystinuria. Am J Physiol Renal Physiol 2014; 306:F1462-76. [DOI: 10.1152/ajprenal.00623.2013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The kidney is one of the major loci for the expression of cystathionine β-synthase (CBS) and cystathionine γ-lyase (CTH). While CBS-deficient ( Cbs−/−) mice display homocysteinemia/methioninemia and severe growth retardation, and rarely survive beyond the first 4 wk, CTH-deficient ( Cth−/−) mice show homocysteinemia/cystathioninemia but develop with no apparent abnormality. This study examined renal amino acid reabsorption in those mice. Although both 2-wk-old Cbs−/− and Cth−/− mice had normal renal architecture, their serum/urinary amino acid profiles largely differed from wild-type mice. The most striking feature was marked accumulation of Met and cystathionine in serum/urine/kidney samples of Cbs−/− and Cth−/− mice, respectively. Levels of some neutral amino acids (Val, Leu, Ile, and Tyr) that were not elevated in Cbs−/− serum were highly elevated in Cbs−/− urine, and urinary excretion of other neutral amino acids (except Met) was much higher than expected from their serum levels, demonstrating neutral aminoaciduria in Cbs−/− (not Cth−/−) mice. Because the bulk of neutral amino acids is absorbed via a B0AT1 transporter and Met has the highest substrate affinity for B0AT1 than other neutral amino acids, hypermethioninemia may cause hyperexcretion of neutral amino acids.
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Affiliation(s)
- Noriyuki Akahoshi
- Department of Molecular and Cellular Neurobiology, Gunma University Graduate School of Medicine, Gunma, Japan
- Japan Science and Technology Agency (JST), Exploratory Research for Advanced Technology (ERATO), Suematsu Gas Biology Project, Tokyo, Japan
- Department of Immunology, Akita University Graduate School of Medicine, Akita, Japan; and
| | - Shotaro Kamata
- Department of Biochemistry, Keio University Graduate School of Pharmaceutical Sciences, Tokyo, Japan
| | - Masashi Kubota
- Department of Biochemistry, Keio University Graduate School of Pharmaceutical Sciences, Tokyo, Japan
| | - Takako Hishiki
- Japan Science and Technology Agency (JST), Exploratory Research for Advanced Technology (ERATO), Suematsu Gas Biology Project, Tokyo, Japan
| | - Yoshiko Nagahata
- Japan Science and Technology Agency (JST), Exploratory Research for Advanced Technology (ERATO), Suematsu Gas Biology Project, Tokyo, Japan
| | - Tomomi Matsuura
- Japan Science and Technology Agency (JST), Exploratory Research for Advanced Technology (ERATO), Suematsu Gas Biology Project, Tokyo, Japan
| | - Chiho Yamazaki
- Department of Molecular and Cellular Neurobiology, Gunma University Graduate School of Medicine, Gunma, Japan
| | - Yuka Yoshida
- Department of Molecular and Cellular Neurobiology, Gunma University Graduate School of Medicine, Gunma, Japan
| | - Hidenori Yamada
- Department of Molecular and Cellular Neurobiology, Gunma University Graduate School of Medicine, Gunma, Japan
| | - Yasuki Ishizaki
- Department of Molecular and Cellular Neurobiology, Gunma University Graduate School of Medicine, Gunma, Japan
| | - Makoto Suematsu
- Japan Science and Technology Agency (JST), Exploratory Research for Advanced Technology (ERATO), Suematsu Gas Biology Project, Tokyo, Japan
| | - Tadashi Kasahara
- Department of Biochemistry, Keio University Graduate School of Pharmaceutical Sciences, Tokyo, Japan
| | - Isao Ishii
- Department of Molecular and Cellular Neurobiology, Gunma University Graduate School of Medicine, Gunma, Japan
- Department of Biochemistry, Keio University Graduate School of Pharmaceutical Sciences, Tokyo, Japan
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37
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Li Z, Gherasim C, Lesniak NA, Banerjee R. Glutathione-dependent one-electron transfer reactions catalyzed by a B₁₂ trafficking protein. J Biol Chem 2014; 289:16487-97. [PMID: 24742678 DOI: 10.1074/jbc.m114.567339] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
CblC is involved in an early step in cytoplasmic cobalamin processing following entry of the cofactor into the cytoplasm. CblC converts the cobalamin cargo arriving from the lysosome to a common cob(II)alamin intermediate, which can be subsequently converted to the biologically active forms. Human CblC exhibits glutathione (GSH)-dependent alkyltransferase activity and flavin-dependent reductive decyanation activity with cyanocobalamin (CNCbl). In this study, we discovered two new GSH-dependent activities associated with the Caenorhabditis elegans CblC for generating cob(II)alamin: decyanation of CNCbl and reduction of aquocobalamin (OH2Cbl). We subsequently found that human CblC also catalyzes GSH-dependent decyanation of CNCbl and reduction of OH2Cbl, albeit efficiently only under anaerobic conditions. The air sensitivity of the human enzyme suggests interception by oxygen during the single-electron transfer step from GSH to CNCbl. These newly discovered GSH-dependent single-electron transfer reactions expand the repertoire of catalytic activities supported by CblC, a versatile B12-processing enzyme.
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Affiliation(s)
- Zhu Li
- From the Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600
| | - Carmen Gherasim
- From the Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600
| | - Nicholas A Lesniak
- From the Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600
| | - Ruma Banerjee
- From the Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0600
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Abstract
SIGNIFICANCE Hydrogen sulfide (H2S), produced by the desulfuration of cysteine or homocysteine, functions as a signaling molecule in an array of physiological processes including regulation of vascular tone, the cellular stress response, apoptosis, and inflammation. RECENT ADVANCES The low steady-state levels of H2S in mammalian cells have been recently shown to reflect a balance between its synthesis and its clearance. The subversion of enzymes in the cytoplasmic trans-sulfuration pathway for producing H2S from cysteine and/or homocysteine versus producing cysteine from homocysteine, presents an interesting regulatory problem. CRITICAL ISSUES It is not known under what conditions the enzymes operate in the canonical trans-sulfuration pathway and how their specificity is switched to catalyze the alternative H2S-producing reactions. Similarly, it is not known if and whether the mitochondrial enzymes, which oxidize sulfide and persulfide (or sulfane sulfur), are regulated to increase or decrease H2S or sulfane-sulfur pools. FUTURE DIRECTIONS In this review, we focus on the enzymology of H2S homeostasis and discuss H2S-based signaling via persulfidation and thionitrous acid.
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Affiliation(s)
- Omer Kabil
- Department of Biological Chemistry, University of Michigan Medical School , Ann Arbor, Michigan
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39
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Stanger O, Fowler B, Piertzik K, Huemer M, Haschke-Becher E, Semmler A, Lorenzl S, Linnebank M. Homocysteine, folate and vitamin B12in neuropsychiatric diseases: review and treatment recommendations. Expert Rev Neurother 2014; 9:1393-412. [DOI: 10.1586/ern.09.75] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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40
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Hourihan JM, Kenna JG, Hayes JD. The gasotransmitter hydrogen sulfide induces nrf2-target genes by inactivating the keap1 ubiquitin ligase substrate adaptor through formation of a disulfide bond between cys-226 and cys-613. Antioxid Redox Signal 2013; 19:465-81. [PMID: 23145493 DOI: 10.1089/ars.2012.4944] [Citation(s) in RCA: 194] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
AIMS The signaling molecule hydrogen sulfide (H2S) protects cells against oxidative stress and activates NF-E2 p45-related factor 2 (Nrf2), a transcription factor that regulates antioxidant genes. We sought to establish whether H2S requires Nrf2 to protect against oxidative stress, and whether activation of Nrf2 by H2S involves antagonism of Kelch-like ECH-associated protein-1 (Keap1), a redox-sensitive ubiquitin ligase substrate adaptor that represses Nrf2 under normal homeostatic conditions. RESULTS H2S stabilizes Nrf2 protein and induces Nrf2-target genes via an antioxidant-/electrophile-response element. In mouse embryonic fibroblasts, the ability of H2S to protect against cell death caused by the redox-cycling agent menadione is dependent on Nrf2. Moreover, Nrf2 regulates murine genes involved in the production of H2S (Cystathionine-beta-synthase [Cbs] and Cystathionine-gamma-lyase [Cse]) and the degradation of H2S (Sulfide:quinone reductase-like [yeast] [Sqrdl]). We found that H2S stabilizes Nrf2 through inhibition of Keap1, an event that requires covalent modification of amino acids C226 and C613 in the substrate adaptor. Upregulation of Nrf2 by H2S partially involves the production of H2O2, which inhibits Keap1 by stimulating the formation of an intramolecular disulfide bond between C226 and C613. The Keap1 C226 and C613 residues are also S-sulfhydrated by H2S, and this may entail reduction of the C226-C613 disulfide bridge formed by H2O2. INNOVATION Upregulation of Nrf2 by H2S and H2O2 involves inactivation of Keap1 through modification of C226 and C613. CONCLUSION Inhibition of Keap1 by H2S leads to Nrf2-mediated induction of cytoprotective genes. Nrf2 controls Cbs, Cse, and Sqrdl, suggesting that a feedback loop exists between Nrf2 and H2S.
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Affiliation(s)
- John M Hourihan
- Jacqui Wood Cancer Centre, Division of Cancer Research, Ninewells Hospital and Medical School, University of Dundee , Dundee, Scotland, United Kingdom
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41
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Vitvitsky V, Martinov M, Ataullakhanov F, Miller RA, Banerjee R. Sulfur-based redox alterations in long-lived Snell dwarf mice. Mech Ageing Dev 2013; 134:321-30. [PMID: 23707637 DOI: 10.1016/j.mad.2013.05.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 03/29/2013] [Accepted: 05/01/2013] [Indexed: 02/08/2023]
Abstract
Changes in sulfur-based redox metabolite profiles in multiple tissues of long-lived Snell dwarf mice were compared with age- and sex-matched controls. Plasma methionine and its oxidation products, hypotaurine and taurine, were increased in Snell dwarfs while cystine and glutathione levels were decreased, leading to an oxidative shift in the redox potential. Sexual dimorphism in renal cystathionine β-synthase (CBS) activity was observed in control mice but not in Snell dwarfs. Instead, female Snell mice exhibited ~2-fold higher CBS activity, comparable to levels seen in male Snell dwarf and in control mice. Taurine levels were significantly higher in kidney and brain of Snell dwarf versus control mice. Methionine adenosyltransferase (MAT) was higher in liver of Snell dwarfs, and the higher concentration of its product, S-adenosylmethionine, was correlated with elevated global DNA methylation status. Application of a mathematical model for methionine metabolism revealed that the metabolite perturbations in Snell dwarfs could be explained by decreased methionine transport, increased MAT and increased methyltransferase activity. Our study provides a comprehensive map of systemic differences in the sulfur network between Snell dwarfs and controls, providing the necessary foundation for assessment of nutrition-linked metabolic status in long-lived versus control animals.
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Affiliation(s)
- Victor Vitvitsky
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109-0600, USA.
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42
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Homocysteine inhibits hepatocyte proliferation via endoplasmic reticulum stress. PLoS One 2013; 8:e54265. [PMID: 23349842 PMCID: PMC3551933 DOI: 10.1371/journal.pone.0054265] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 12/10/2012] [Indexed: 01/30/2023] Open
Abstract
Homocysteine is an independent risk factor for coronary, cerebral, and peripheral vascular diseases. Recent studies have shown that levels of homocysteine are elevated in patients with impaired hepatic function, but the precise role of homocysteine in the development of hepatic dysfunction is unclear. In this study, we examined the effect of homocysteine on hepatocyte proliferation in vitro. Our results demonstrated that homocysteine inhibited hepatocyte proliferation by up-regulating protein levels of p53 as well as mRNA and protein levels of p21Cip1 in primary cultured hepatocytes. Homocysteine induced cell growth arrest in p53-positive hepatocarcinoma cell line HepG2, but not in p53-null hepatocarcinoma cell line Hep3B. A p53 inhibitor pifithrin-α inhibited the expression of p21Cip1 and attenuated homocysteine-induced cell growth arrest. Homocysteine induced TRB3 expression via endoplasmic reticulum stress pathway, resulting in Akt dephosphorylation. Knock-down of endogenous TRB3 significantly suppressed the inhibitory effect of homocysteine on cell proliferation and the phosphorylation of Akt. LiCl reversed homocysteine-mediated cell growth arrest by inhibiting TRB3-mediated Akt dephosphorylation. These results demonstrate that both TRB3 and p21Cip1 are critical molecules in the homocysteine signaling cascade and provide a mechanistic explanation for impairment of liver regeneration in hyperhomocysteinemia.
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Vitvitsky V, Kabil O, Banerjee R. High turnover rates for hydrogen sulfide allow for rapid regulation of its tissue concentrations. Antioxid Redox Signal 2012; 17:22-31. [PMID: 22229551 PMCID: PMC3342560 DOI: 10.1089/ars.2011.4310] [Citation(s) in RCA: 161] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
AIMS Hydrogen sulfide (H(2)S) is a signaling molecule, which influences many physiological processes. While H(2)S is produced and degraded in many cell types, the kinetics of its turnover in different tissues has not been reported. In this study, we have assessed the rates of H(2)S production in murine liver, kidney, and brain homogenates at pH 7.4, 37°C, and at physiologically relevant cysteine concentrations. We have also studied the kinetics of H(2)S clearance by liver, kidney, and brain homogenates under aerobic and anaerobic conditions. RESULTS We find that the rate of H(2)S production by these tissue homogenates is considerably higher than background rates observed in the absence of exogenous substrates. An exponential decay of H(2)S with time is observed and, as expected, is significantly faster under aerobic conditions. The half-life for H(2)S under aerobic conditions is 2.0, 2.8, and 10.0 min with liver, kidney, and brain homogenate, respectively. Western-blot analysis of the sulfur dioxygenase, ETHE1, involved in H(2)S catabolism, demonstrates higher steady-state protein levels in liver and kidney versus brain. INNOVATION By combining experimental and simulation approaches, we demonstrate high rates of tissue H(2)S turnover and provide estimates of steady-state H(2)S levels. CONCLUSION Our study reveals that tissues maintain a high metabolic flux of sulfur through H(2)S, providing a rationale for how H(2)S levels can be rapidly regulated.
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Affiliation(s)
- Victor Vitvitsky
- Biological Chemistry Department, University of Michigan Medical Center, Ann Arbor, Michigan 48109-0600, USA
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44
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Smach MA, Naffeti S, Charfeddine B, Ben Abdallah J, Othmen LB, Letaef A, Limem K. [Homocysteine, vitamin B-12, folic acid and the cognitive decline in the elderly]. ACTA ACUST UNITED AC 2012; 61:184-92. [PMID: 22647793 DOI: 10.1016/j.patbio.2012.04.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Accepted: 04/18/2012] [Indexed: 11/25/2022]
Abstract
Hyperhomocysteinemia is a risk factor for neurological diseases, but the underlying pathophysiology has not been adequately explained. Mild hyperhomocysteinemia, which is sometimes associated with a low plasma level of vitamin B9, B12 and folic acid, is responsible in the toxicity in neural cell by activating NMDA receptor. Indeed, even if vitamin supplementation has clearly proven its efficiency on lowering plasma levels of homocysteine, recent studies do not show any positive effect of vitamin therapy on cognitive function. The hypothesis that this therapy is inefficient has been recently reinforced by two randomized trials on the effects of vitamin supplementation. Several hypotheses still need to be explored: Mechanisms of homocysteine toxicity and that of total uselessness of vitamin supplementation; the possible need to complete the actual data with further, more powerful studies in order to prove the role of homocysteine in the development of neurodegenerative diseases and a clinical effect of vitamin therapy.
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Affiliation(s)
- M A Smach
- Department of Biochemistry, Faculty of Medicine of Sousse, 4002 Sousse, Tunisie.
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45
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HMGA1 is a novel downstream nuclear target of the insulin receptor signaling pathway. Sci Rep 2012; 2:251. [PMID: 22355763 PMCID: PMC3273854 DOI: 10.1038/srep00251] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Accepted: 01/18/2012] [Indexed: 02/07/2023] Open
Abstract
High-mobility group AT-hook 1 (HMGA1) protein is an important nuclear factor that activates gene transcription by binding to AT-rich sequences in the promoter region of DNA. We previously demonstrated that HMGA1 is a key regulator of the insulin receptor (INSR) gene and individuals with defects in HMGA1 have decreased INSR expression and increased susceptibility to type 2 diabetes mellitus. In addition, there is evidence that intracellular regulatory molecules that are employed by the INSR signaling system are involved in post-translational modifications of HMGA1, including protein phosphorylation. It is known that phosphorylation of HMGA1 reduces DNA-binding affinity and transcriptional activation. In the present study, we investigated whether activation of the INSR by insulin affected HMGA1 protein phosphorylation and its regulation of gene transcription. Collectively, our findings indicate that HMGA1 is a novel downstream target of the INSR signaling pathway, thus representing a new critical nuclear mediator of insulin action and function.
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46
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Mudd SH, Wagner C, Luka Z, Stabler SP, Allen RH, Schroer R, Wood T, Wang J, Wong LJ. Two patients with hepatic mtDNA depletion syndromes and marked elevations of S-adenosylmethionine and methionine. Mol Genet Metab 2012; 105:228-36. [PMID: 22137549 PMCID: PMC3264801 DOI: 10.1016/j.ymgme.2011.11.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Revised: 11/07/2011] [Accepted: 11/07/2011] [Indexed: 02/07/2023]
Abstract
This paper reports studies of two patients proven by a variety of studies to have mitochondrial depletion syndromes due to mutations in either their MPV17 or DGUOK genes. Each was initially investigated metabolically because of plasma methionine concentrations as high as 15-21-fold above the upper limit of the reference range, then found also to have plasma levels of S-adenosylmethionine (AdoMet) 4.4-8.6-fold above the upper limit of the reference range. Assays of S-adenosylhomocysteine, total homocysteine, cystathionine, sarcosine, and other relevant metabolites and studies of their gene encoding glycine N-methyltransferase produced evidence suggesting they had none of the known causes of elevated methionine with or without elevated AdoMet. Patient 1 grew slowly and intermittently, but was cognitively normal. At age 7 years he was found to have hepatocellular carcinoma, underwent a liver transplant and died of progressive liver and renal failure at age almost 9 years. Patient 2 had a clinical course typical of DGUOK deficiency and died at age 8 ½ months. Although each patient had liver abnormalities, evidence is presented that such abnormalities are very unlikely to explain their elevations of AdoMet or the extent of their hypermethioninemias. A working hypothesis is presented suggesting that with mitochondrial depletion the normal usage of AdoMet by mitochondria is impaired, AdoMet accumulates in the cytoplasm of affected cells poor in glycine N-methyltransferase activity, the accumulated AdoMet causes methionine to accumulate by inhibiting activity of methionine adenosyltransferase II, and that both AdoMet and methionine consequently leak abnormally into the plasma.
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Affiliation(s)
- S Harvey Mudd
- Laboratory of Molecular Biology, National Institute of Mental Health, Bethesda, MD 20892, USA.
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47
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Régnier V, Billard JM, Gupta S, Potier B, Woerner S, Paly E, Ledru A, David S, Luilier S, Bizot JC, Vacano G, Kraus JP, Patterson D, Kruger WD, Delabar JM, London J. Brain phenotype of transgenic mice overexpressing cystathionine β-synthase. PLoS One 2012; 7:e29056. [PMID: 22253703 PMCID: PMC3257219 DOI: 10.1371/journal.pone.0029056] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Accepted: 11/20/2011] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The cystathionine β-synthase (CBS) gene, located on human chromosome 21q22.3, is a good candidate for playing a role in the Down Syndrome (DS) cognitive profile: it is overexpressed in the brain of individuals with DS, and it encodes a key enzyme of sulfur-containing amino acid (SAA) metabolism, a pathway important for several brain physiological processes. METHODOLOGY/PRINCIPAL FINDINGS Here, we have studied the neural consequences of CBS overexpression in a transgenic mouse line (60.4P102D1) expressing the human CBS gene under the control of its endogenous regulatory regions. These mice displayed a ∼2-fold increase in total CBS proteins in different brain areas and a ∼1.3-fold increase in CBS activity in the cerebellum and the hippocampus. No major disturbance of SAA metabolism was observed, and the transgenic mice showed normal behavior in the rotarod and passive avoidance tests. However, we found that hippocampal synaptic plasticity is facilitated in the 60.4P102D1 line. CONCLUSION/SIGNIFICANCE We demonstrate that CBS overexpression has functional consequences on hippocampal neuronal networks. These results shed new light on the function of the CBS gene, and raise the interesting possibility that CBS overexpression might have an advantageous effect on some cognitive functions in DS.
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Affiliation(s)
- Vinciane Régnier
- Unité de Biologie Fonctionnelle et Adaptative, CNRS EAC 4413, Université Paris Diderot, Sorbonne Paris Cité, Paris, France.
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48
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Dickhout JG, Carlisle RE, Jerome DE, Mohammed-Ali Z, Jiang H, Yang G, Mani S, Garg SK, Banerjee R, Kaufman RJ, Maclean KN, Wang R, Austin RC. Integrated stress response modulates cellular redox state via induction of cystathionine γ-lyase: cross-talk between integrated stress response and thiol metabolism. J Biol Chem 2012; 287:7603-14. [PMID: 22215680 DOI: 10.1074/jbc.m111.304576] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The integrated stress response mediated by eukaryotic translation initiation factor 2α (eIF2α) phosphorylation maintains cellular homeostasis under endoplasmic reticulum (ER) stress. eIF2α phosphorylation induces activating transcription factor 4 (ATF4), a basic leucine zipper transcription factor that regulates the expression of genes responsible for amino acid metabolism, cellular redox state, and anti-stress responses. Cystathionine γ-lyase (CSE) and cystathionine β-synthase are critical enzymes in the transsulfuration pathway, which also regulate cellular redox status by modulating glutathione (GSH) levels. To determine the link between the integrated stress response and the transsulfuration pathway, we used homocysteine (Hcy) as an inducer of eIF2α phosphorylation and ATF4 gene induction. Mouse embryonic fibroblasts (MEFs) lacking ATF4 (ATF4(-/-)) had reduced GSH levels and increased reactive oxygen species and were susceptible to apoptotic cell death under normal culture conditions. Further, ATF4(-/-) MEFs were more sensitive to Hcy-induced cytotoxicity and showed significantly reduced intracellular GSH levels associated with apoptosis. ATF4(-/-) MEFs could be rescued from l-Hcy-induced apoptosis by β-mercaptoethanol medium supplementation that increases cysteine levels and restores GSH synthesis. ATF4(-/-) MEFs showed little or no CSE protein but did express cystathionine β-synthase. Further, ER stress-inducing agents, including tunicamycin and thapsigargin, induced the expression of CSE in ATF4(+/+) MEFs. Consistent with ATF4(-/-) MEFs, CSE(-/-) MEFs showed significantly greater apoptosis when treated with tunicamycin, thapsigargin, and l-Hcy, compared with CSE(+/+) MEFs. Liver and kidney GSH levels were also reduced in CSE(-/-) mice, suggesting that CSE is a critical factor in GSH synthesis and may act to protect the liver and kidney from a variety of conditions that cause ER stress.
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Affiliation(s)
- Jeffrey G Dickhout
- Department of Medicine, Division of Nephrology, McMaster University, St. Joseph's Healthcare Hamilton and Hamilton Centre for Kidney Research, Hamilton, Ontario L8N 4A6, Canada
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49
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Carrillo-Carrasco N, Venditti CP. Combined methylmalonic acidemia and homocystinuria, cblC type. II. Complications, pathophysiology, and outcomes. J Inherit Metab Dis 2012; 35:103-14. [PMID: 21748408 PMCID: PMC3529128 DOI: 10.1007/s10545-011-9365-x] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 05/27/2011] [Accepted: 06/09/2011] [Indexed: 02/07/2023]
Abstract
Combined methylmalonic acidemia and homocystinuria, cblC type, is stated to be the most common inborn error of intracellular cobalamin metabolism. The disorder can display a wide spectrum of clinical manifestations, spanning the prenatal period through late adulthood. While increased homocysteine concentrations and impaired methyl group metabolism may contribute to disease-related complications, the characteristic macular and retinal degeneration seen in many affected patients appears to be unique to cblC disease. The early detection of cblC disease by newborn screening mandates a careful assessment of therapeutic approaches and provides a new opportunity to improve the outcome of affected patients. The following article reviews the current knowledge on the complications, pathophysiology, and outcome of cblC disease in an effort to better guide clinical practice and future therapeutic trials.
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Affiliation(s)
- Nuria Carrillo-Carrasco
- Organic Acid Research Section, Genetics and Molecular Biology Branch, National Human Genome Research Institute, National Institutes of Health, Building 49, Room 4A18, Bethesda, MD 20892, USA
| | - Charles P. Venditti
- Organic Acid Research Section, Genetics and Molecular Biology Branch, National Human Genome Research Institute, National Institutes of Health, Building 49, Room 4A18, Bethesda, MD 20892, USA
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50
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Kriebitzsch C, Verlinden L, Eelen G, van Schoor NM, Swart K, Lips P, Meyer MB, Pike JW, Boonen S, Carlberg C, Vitvitsky V, Bouillon R, Banerjee R, Verstuyf A. 1,25-dihydroxyvitamin D3 influences cellular homocysteine levels in murine preosteoblastic MC3T3-E1 cells by direct regulation of cystathionine β-synthase. J Bone Miner Res 2011; 26:2991-3000. [PMID: 21898591 PMCID: PMC3222742 DOI: 10.1002/jbmr.493] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
High homocysteine (HCY) levels are a risk factor for osteoporotic fracture. Furthermore, bone quality and strength are compromised by elevated HCY owing to its negative impact on collagen maturation. HCY is cleared by cystathionine β-synthase (CBS), the first enzyme in the transsulfuration pathway. CBS converts HCY to cystathionine, thereby committing it to cysteine synthesis. A microarray experiment on MC3T3-E1 murine preosteoblasts treated with 1,25-dihydroxyvitamin D(3) [1,25(OH)(2) D(3) ] revealed a cluster of genes including the cbs gene, of which the transcription was rapidly and strongly induced by 1,25(OH)(2) D(3) . Quantitative real-time PCR and Western blot analysis confirmed higher levels of cbs mRNA and protein after 1,25(OH)(2) D(3) treatment in murine and human cells. Moreover, measurement of CBS enzyme activity and quantitative measurements of HCY, cystathionine, and cysteine concentrations were consistent with elevated transsulfuration activity in 1,25(OH)(2) D(3) -treated cells. The importance of a functional vitamin D receptor (VDR) for transcriptional regulation of cbs was shown in primary murine VDR knockout osteoblasts, in which upregulation of cbs in response to 1,25(OH)(2) D(3) was abolished. Chromatin immunoprecipitation on chip and transfection studies revealed a functional vitamin D response element in the second intron of cbs. To further explore the potential clinical relevance of our ex vivo findings, human data from the Longitudinal Aging Study Amsterdam suggested a correlation between vitamin D status [25(OH)D(3) levels] and HCY levels. In conclusion, this study showed that cbs is a primary 1,25(OH)(2) D(3) target gene which renders HCY metabolism responsive to 1,25(OH)(2) D(3).
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Affiliation(s)
- Carsten Kriebitzsch
- Laboratory for Experimental Medicine and Endocrinology (LEGENDO), Catholic University of Leuven, Gasthuisberg O&N 1, Herestraat 49, B-3000 Leuven, Belgium
| | - Lieve Verlinden
- Laboratory for Experimental Medicine and Endocrinology (LEGENDO), Catholic University of Leuven, Gasthuisberg O&N 1, Herestraat 49, B-3000 Leuven, Belgium
| | - Guy Eelen
- Laboratory for Experimental Medicine and Endocrinology (LEGENDO), Catholic University of Leuven, Gasthuisberg O&N 1, Herestraat 49, B-3000 Leuven, Belgium
| | - Natasja M. van Schoor
- Department of Internal Medicine, Endocrine Section and EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
| | - Karin Swart
- Department of Internal Medicine, Endocrine Section and EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
| | - Paul Lips
- Department of Internal Medicine, Endocrine Section and EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
| | - Mark B. Meyer
- Department of Biochemistry, University of Wisconsin at Madison, Madison, WI, USA 53706
| | - J Wesley Pike
- Department of Biochemistry, University of Wisconsin at Madison, Madison, WI, USA 53706
| | - Steven Boonen
- Leuven University Center for Metabolic Bone Disease and Division of Geriatric Medicine, Leuven, Belgium
| | - Carsten Carlberg
- Department of Biosciences, University of Eastern Finland, FI-70211 Kuopio, Finland
| | - Victor Vitvitsky
- Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, MI, 48109-0600, USA
| | - Roger Bouillon
- Laboratory for Experimental Medicine and Endocrinology (LEGENDO), Catholic University of Leuven, Gasthuisberg O&N 1, Herestraat 49, B-3000 Leuven, Belgium
| | - Ruma Banerjee
- Department of Biological Chemistry, University of Michigan Medical Center, Ann Arbor, MI, 48109-0600, USA
| | - Annemieke Verstuyf
- Laboratory for Experimental Medicine and Endocrinology (LEGENDO), Catholic University of Leuven, Gasthuisberg O&N 1, Herestraat 49, B-3000 Leuven, Belgium
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