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Buonvino S, Arciero I, Melino S. Thiosulfate-Cyanide Sulfurtransferase a Mitochondrial Essential Enzyme: From Cell Metabolism to the Biotechnological Applications. Int J Mol Sci 2022; 23:ijms23158452. [PMID: 35955583 PMCID: PMC9369223 DOI: 10.3390/ijms23158452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 07/27/2022] [Accepted: 07/27/2022] [Indexed: 11/16/2022] Open
Abstract
Thiosulfate: cyanide sulfurtransferase (TST), also named rhodanese, is an enzyme widely distributed in both prokaryotes and eukaryotes, where it plays a relevant role in mitochondrial function. TST enzyme is involved in several biochemical processes such as: cyanide detoxification, the transport of sulfur and selenium in biologically available forms, the restoration of iron–sulfur clusters, redox system maintenance and the mitochondrial import of 5S rRNA. Recently, the relevance of TST in metabolic diseases, such as diabetes, has been highlighted, opening the way for research on important aspects of sulfur metabolism in diabetes. This review underlines the structural and functional characteristics of TST, describing the physiological role and biomedical and biotechnological applications of this essential enzyme.
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Jurkowska H, Wróbel M, Jasek-Gajda E, Rydz L. Sulfurtransferases and Cystathionine Beta-Synthase Expression in Different Human Leukemia Cell Lines. Biomolecules 2022; 12:biom12020148. [PMID: 35204649 PMCID: PMC8961552 DOI: 10.3390/biom12020148] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 01/14/2022] [Accepted: 01/16/2022] [Indexed: 12/17/2022] Open
Abstract
The studies concerned the expression of sulfurtransferases and cystathionine beta-synthase in six human leukemia cell lines: B cell acute lymphoblastic leukemia-B-ALL (REH cells), T cell acute lymphoblastic leukemia-T-ALL (DND-41 and MOLT-4 cells), acute myeloid leukemia—AML (MV4-11 and MOLM-14 cells), and chronic myeloid leukemia—CML (K562 cells). Reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis were performed to determine the expression of thiosulfate sulfurtransferase, 3-mercaptopyruvate sulfurtransferase, gamma-cystathionase, and cystathionine beta-synthase on the mRNA and protein level. Interestingly, we found significant differences in the mRNA and protein levels of sulfurtransferases and cystathionine beta-synthase in the studied leukemia cells. The obtained results may contribute to elucidating the significance of the differences between the studied cells in the field of sulfur compound metabolism and finding new promising ways to inhibit the proliferation of various types of leukemic cells by modulating the activity of sulfurtransferases, cystathionine beta-synthase, and, consequently, the change of intracellular level of sulfane sulfur as well as H2S and reactive oxygen species production.
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Affiliation(s)
- Halina Jurkowska
- Chair of Medical Biochemistry, Faculty of Medicine, Jagiellonian University Medical College, 7 Kopernika St., 31-034 Kraków, Poland; (M.W.); (L.R.)
- Correspondence: ; Tel.: +48-12-422-74-00
| | - Maria Wróbel
- Chair of Medical Biochemistry, Faculty of Medicine, Jagiellonian University Medical College, 7 Kopernika St., 31-034 Kraków, Poland; (M.W.); (L.R.)
| | - Ewa Jasek-Gajda
- Department of Histology, Faculty of Medicine, Jagiellonian University Medical College, 7 Kopernika St., 31-034 Kraków, Poland;
| | - Leszek Rydz
- Chair of Medical Biochemistry, Faculty of Medicine, Jagiellonian University Medical College, 7 Kopernika St., 31-034 Kraków, Poland; (M.W.); (L.R.)
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Kaczor-Kamińska M, Kaminski K, Wróbel M. The Expression and Activity of Rhodanese, 3-Mercaptopyruvate Sulfurtransferase, Cystathionine γ-Lyase in the Most Frequently Chosen Cellular Research Models. Biomolecules 2021; 11:biom11121859. [PMID: 34944503 PMCID: PMC8699783 DOI: 10.3390/biom11121859] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 12/01/2021] [Accepted: 12/07/2021] [Indexed: 11/16/2022] Open
Abstract
This paper provides information concerning the activity and expression levels of three sulfurtransferases (STRs): rhodanese (TST, EC: 2.8.1.1), 3-mercaptopyruvate sulfurtransferase (MPST, EC: 2.8.1.2) and cystathionine γ-lyase (CTH, EC: 4.4.1.1) in various cell lines. Since very limited data are available in the scientific literature on this subject, the available data are included in this paper. These shortages often force the researchers to carry out their own screening tests that allow them to choose an appropriate model for their further studies. This work supplements the existing deficiencies in this area and presents the activity and expression of STRs in the eight most frequently chosen cell lines: the mouse mammary gland cell line (NMuNG, ATCC: CRL-1636), mouse mammary gland tumor (4T1, ATCC: CRL-2539), mouse fibroblast (MEF, ATCC: SCRC-1008), mouse melanoma (B16-F1, ATCC: CRL-6323), human colorectal adenocarcinoma (Caco-2, ATCC: HTB-37), human embryonic kidney (HEK-293, ATCC: CRL-1573), human osteosarcoma (MG-63, ATCC: CRL-1427) and rat myocardium (H9c2, ATCC: CRL-1446). Changes in STRs activity are directly related to the bioavailability of cysteine and the sulfane sulfur level, and thus the present authors also measured these parameters, as well as the level of glutathione (its reduced (GSH) and oxidized (GSSG) form) and the [GSH]/[GSSG] ratio that determines the antioxidant capacity of the cells. STRs demonstrate diverse functionality and clinical relevance; therefore, we also performed an analysis of genetic variation of STRs genes that revealed a large number of polymorphisms. Although STRs still provide challenges in several fields, responding to them could not only improve the understanding of various diseases, but may also provide a way to treat them.
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Affiliation(s)
- Marta Kaczor-Kamińska
- Faculty of Medicine, Medical College, Chair of Medical Biochemistry, Jagiellonian University, Kopernika 7 St., 31-034 Krakow, Poland;
- Correspondence: ; Tel.: +48-12-422-7400
| | - Kamil Kaminski
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2 St., 30-387 Krakow, Poland;
| | - Maria Wróbel
- Faculty of Medicine, Medical College, Chair of Medical Biochemistry, Jagiellonian University, Kopernika 7 St., 31-034 Krakow, Poland;
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4
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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: 128] [Impact Index Per Article: 42.7] [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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5
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Yang B, Zhao W, Yin C, Bai Y, Wang S, Xing G, Li F, Bian J, Aschner M, Cai J, Shi H, Lu R. Acute acrylonitrile exposure inhibits endogenous H 2S biosynthesis in rat brain and liver: The role of CBS/3-MPST-H 2S pathway in its astrocytic toxicity. Toxicology 2021; 451:152685. [PMID: 33486070 DOI: 10.1016/j.tox.2021.152685] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 12/12/2020] [Accepted: 01/15/2021] [Indexed: 12/11/2022]
Abstract
Hydrogen sulfide (H2S) as the third gasotransmitter molecule serves various biological regulatory roles in health and disease. Acrylonitrile (AN) is a common occupational toxicant and environmental pollutant, causing brain and liver damage in mammals. The biotransformation of AN is dependent-upon reduced glutathione (GSH), cysteine and other sulfur-containing compounds. However, the effects of AN on the endogenous H2S biosynthesis pathway have yet to be determined. Herein, we demonstrated that a single exposure to AN (at 25, 50, or 75 mg/kg for 1, 6 or 24 h) decreased the endogenous H2S content and H2S-producing capacity in a dose-dependent manner, both in the cerebral cortex and liver of rats in vivo. In addition, the inhibitory effects of AN (1, 2.5, 5, 10 mM for 12 h) on the H2S content and/or the expression of H2S-producing enzymes were also found both in primary rat astrocytes and rat liver cell line (BRL cells). Impairment in the H2S biosynthesis pathway was also assessed in primary rat astrocytes treated with AN. It was found that inhibition of the cystathionine-β-synthase (CBS)/3-mercaptopyruvate sulfurtransferase (3-MPST)-H2S pathway with the CBS inhibitor or 3-MPST-targeted siRNA significantly increased the AN-induced (5 mM for 12 h) cytotoxicity in astrocytes. In turn, CBS activation or 3-MPST overexpression as well as exogenous NaHS supplementation significantly attenuated AN-induced cytotoxicity. Taken together, endogenous H2S biosynthesis pathway was disrupted in rats acutely exposed to AN, which contributes to acute AN neurotoxicity in primary rat astrocytes.
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Affiliation(s)
- Bobo Yang
- Department of Preventive Medicine and Public Health Laboratory Science, School of Medicine, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu, 212013, China
| | - Wenjun Zhao
- Department of Preventive Medicine and Public Health Laboratory Science, School of Medicine, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu, 212013, China; Department of Clinical Laboratory, Affiliated People's Hospital to Jiangsu University School of Medicine, Zhenjiang, Jiangsu, 212002, China
| | - Changsheng Yin
- Department of Preventive Medicine and Public Health Laboratory Science, School of Medicine, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu, 212013, China
| | - Yu Bai
- Department of Preventive Medicine and Public Health Laboratory Science, School of Medicine, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu, 212013, China
| | - Suhua Wang
- Department of Preventive Medicine and Public Health Laboratory Science, School of Medicine, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu, 212013, China
| | - Guangwei Xing
- Department of Preventive Medicine and Public Health Laboratory Science, School of Medicine, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu, 212013, China
| | - Fang Li
- Department of Preventive Medicine and Public Health Laboratory Science, School of Medicine, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu, 212013, China
| | - Jinsong Bian
- Department of Pharmacology, School of Medicine, National Singapore University, 117597, Singapore
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Jiyang Cai
- Department of Physiology, College of Medicine, University of Oklahoma Health Science Center, Lindsay, Oklahoma City, OK, 73104, USA
| | - Haifeng Shi
- School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, 212013, China
| | - Rongzhu Lu
- Department of Preventive Medicine and Public Health Laboratory Science, School of Medicine, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu, 212013, China; Center for Experimental Research, Affiliated Kunshan Hospital to Jiangsu University School of Medicine, Kunshan, Suzhou, Jiangsu, 215132, China.
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The multifaceted roles of sulfane sulfur species in cancer-associated processes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1862:148338. [PMID: 33212042 DOI: 10.1016/j.bbabio.2020.148338] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 10/30/2020] [Accepted: 11/13/2020] [Indexed: 02/07/2023]
Abstract
Sulfane sulfur species comprise a variety of biologically relevant hydrogen sulfide (H2S)-derived species, including per- and poly-sulfidated low molecular weight compounds and proteins. A growing body of evidence suggests that H2S, currently recognized as a key signaling molecule in human physiology and pathophysiology, plays an important role in cancer biology by modulating cell bioenergetics and contributing to metabolic reprogramming. This is accomplished through functional modulation of target proteins via H2S binding to heme iron centers or H2S-mediated reversible per- or poly-sulfidation of specific cysteine residues. Since sulfane sulfur species are increasingly viewed not only as a major source of H2S but also as key mediators of some of the biological effects commonly attributed to H2S, the multifaceted role of these species in cancer biology is reviewed here with reference to H2S, focusing on their metabolism, signaling function, impact on cell bioenergetics and anti-tumoral properties.
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Zuhra K, Tomé CS, Masi L, Giardina G, Paulini G, Malagrinò F, Forte E, Vicente JB, Giuffrè A. N-Acetylcysteine Serves as Substrate of 3-Mercaptopyruvate Sulfurtransferase and Stimulates Sulfide Metabolism in Colon Cancer Cells. Cells 2019; 8:cells8080828. [PMID: 31382676 PMCID: PMC6721681 DOI: 10.3390/cells8080828] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 07/31/2019] [Accepted: 08/02/2019] [Indexed: 12/12/2022] Open
Abstract
Hydrogen sulfide (H2S) is an endogenously produced signaling molecule. The enzymes 3-mercaptopyruvate sulfurtransferase (MST), partly localized in mitochondria, and the inner mitochondrial membrane-associated sulfide:quinone oxidoreductase (SQR), besides being respectively involved in the synthesis and catabolism of H2S, generate sulfane sulfur species such as persulfides and polysulfides, currently recognized as mediating some of the H2S biological effects. Reprogramming of H2S metabolism was reported to support cellular proliferation and energy metabolism in cancer cells. As oxidative stress is a cancer hallmark and N-acetylcysteine (NAC) was recently suggested to act as an antioxidant by increasing intracellular levels of sulfane sulfur species, here we evaluated the effect of prolonged exposure to NAC on the H2S metabolism of SW480 colon cancer cells. Cells exposed to NAC for 24 h displayed increased expression and activity of MST and SQR. Furthermore, NAC was shown to: (i) persist at detectable levels inside the cells exposed to the drug for up to 24 h and (ii) sustain H2S synthesis by human MST more effectively than cysteine, as shown working on the isolated recombinant enzyme. We conclude that prolonged exposure of colon cancer cells to NAC stimulates H2S metabolism and that NAC can serve as a substrate for human MST.
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Affiliation(s)
- Karim Zuhra
- Department of Biochemical Sciences, Sapienza University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy
- CNR Institute of Molecular Biology and Pathology, Piazzale Aldo Moro 5, I-00185 Rome, Italy
| | - Catarina S Tomé
- Instituto de Tecnologia Química e Biológica António Xavier (ITQB NOVA), Avenida da República (EAN), 2780-157 Oeiras, Portugal
| | - Letizia Masi
- Department of Biochemical Sciences, Sapienza University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy
| | - Giorgio Giardina
- Department of Biochemical Sciences, Sapienza University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy
| | - Giulia Paulini
- Department of Biochemical Sciences, Sapienza University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy
| | - Francesca Malagrinò
- Department of Biochemical Sciences, Sapienza University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy
| | - Elena Forte
- Department of Biochemical Sciences, Sapienza University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy.
| | - João B Vicente
- Instituto de Tecnologia Química e Biológica António Xavier (ITQB NOVA), Avenida da República (EAN), 2780-157 Oeiras, Portugal.
| | - Alessandro Giuffrè
- CNR Institute of Molecular Biology and Pathology, Piazzale Aldo Moro 5, I-00185 Rome, Italy.
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8
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Gao M, Wang R, Yu F, Li B, Chen L. Imaging of intracellular sulfane sulfur expression changes under hypoxic stress via a selenium-containing near-infrared fluorescent probe. J Mater Chem B 2018; 6:6637-6645. [PMID: 32254872 DOI: 10.1039/c8tb01794h] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Hypoxia is a significant global issue affecting the health of organisms. Oxygen homeostasis is critical for mammalian cell survival and cellular activities. Hypoxic stress can lead to cell injury and death, which contributes to many diseases. Sulfane sulfur is involved in crucial roles in physiological processes of maintaining intracellular redox state and ameliorating oxidative damage. Therefore, real-time imaging of changes in sulfane sulfur levels is important for understanding their biofunctions in cells. In this study, we develop a new near-infrared (NIR) fluorescent probe BD-diSeH for imaging of sulfane sulfur changes in cells and in vivo under hypoxic stress. The probe includes two moieties: an NIR azo-BODIPY fluorophore equipped with a strong nucleophilic phenylselenol group (-SeH). The probe is capable of tracing dynamic changes of endogenous sulfane sulfur based on a fast and spontaneous intramolecular cyclization reaction. The probe has been successfully used for imaging sulfane sulfur in 3D-multicellular spheroid and mouse hippocampus under hypoxic stress. The overall levels of sulfane sulfur are affected by the degree and length of hypoxic stress. The results reveal a close relationship between sulfane sulfur and hypoxia in living cells and in vivo, allowing better understanding of physiological and pathological processes involving sulfane sulfur. Moreover, to investigate the effects of environmental hypoxia on aquatic animals, this probe has been applied for sulfane sulfur detection in hypoxic zebrafish.
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Affiliation(s)
- Min Gao
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China.
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9
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Berberova NT, Smolyaninov IV, Shinkar EV, Kuzmin VV, Sediki DB, Shevtsova AV. Electrosynthesis of biologically active dicycloalkyl di- and trisulfides involving an H2S—S8 redox system. Russ Chem Bull 2018. [DOI: 10.1007/s11172-018-2044-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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10
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Gao M, Wang R, Yu F, You J, Chen L. Imaging and evaluation of sulfane sulfur in acute brain ischemia using a mitochondria-targeted near-infrared fluorescent probe. J Mater Chem B 2018; 6:2608-2619. [DOI: 10.1039/c7tb03200e] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Imaging and evaluation of sulfane sulfur in acute brain ischemia using a mitochondria-targeted near-infrared fluorescent probe
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Affiliation(s)
- Min Gao
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation
- Research Centre for Coastal Environmental Engineering and Technology
- Yantai Institute of Coastal Zone Research
- Chinese Academy of Sciences
- Yantai 264003
| | - Rui Wang
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation
- Research Centre for Coastal Environmental Engineering and Technology
- Yantai Institute of Coastal Zone Research
- Chinese Academy of Sciences
- Yantai 264003
| | - Fabiao Yu
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation
- Research Centre for Coastal Environmental Engineering and Technology
- Yantai Institute of Coastal Zone Research
- Chinese Academy of Sciences
- Yantai 264003
| | - Jinmao You
- Key Laboratory of Life-Organic Analysis
- Key Laboratory of Pharmaceutical Intermediates and Analysis of Natural Medicine
- College of Chemistry and Chemical Engineering
- Qufu Normal University
- Qufu 273165
| | - Lingxin Chen
- Key Laboratory of Coastal Environmental Processes and Ecological Remediation
- Research Centre for Coastal Environmental Engineering and Technology
- Yantai Institute of Coastal Zone Research
- Chinese Academy of Sciences
- Yantai 264003
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11
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Atomic Sulfur: An Element for Adaptation to an Oxidative Environment. Molecules 2017; 22:molecules22111821. [PMID: 29072603 PMCID: PMC6150329 DOI: 10.3390/molecules22111821] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 10/24/2017] [Indexed: 11/30/2022] Open
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12
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Jurkowska H, Wróbel M, Kaczor-Kamińska M, Jasek-Gajda E. A possible mechanism of inhibition of U87MG and SH-SY5Y cancer cell proliferation by diallyl trisulfide and other aspects of its activity. Amino Acids 2017; 49:1855-1866. [PMID: 28852876 PMCID: PMC5646106 DOI: 10.1007/s00726-017-2484-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 08/18/2017] [Indexed: 01/15/2023]
Abstract
The study was conducted to elucidate the mechanism of antiproliferative and antioxidative action of diallyl trisulfide (DATS), a garlic-derived organosulfur compound. Changes in the l-cysteine desulfuration, and the levels of cystathionine and non-protein thiols in DATS-treated human glioblastoma (U87MG) and neuroblastoma (SH-SY5Y) cells were investigated. The inhibition of proliferation of the investigated cells by DATS was correlated with an increase in the inactivated form of Bcl-2. In U87MG cells, an increased level of sulfane sulfur and an increased activity of 3-mercaptopyruvate sulfurtransferase (MPST) and rhodanese, the enzymes involved in sulfane sulfur generation and transfer, suggest that DATS can function as a donor of sulfane sulfur atom, transferred by sulfurtransferases, to sulfhydryl groups of cysteine residues of Bcl-2 and in this way lower the level of active form of Bcl-2 by S-sulfuration. Diallyl trisulfide antioxidative effects result from an increased level of cystathionine, a precursor of cysteine, and an increased glutathione level. MPST and rhodanese, the level of which is increased in the presence of DATS, can serve as antioxidant proteins.
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Affiliation(s)
- Halina Jurkowska
- Chair of Medical Biochemistry, Jagiellonian University Medical College, 7 Kopernika St, 31-034, Kraków, Poland.
| | - Maria Wróbel
- Chair of Medical Biochemistry, Jagiellonian University Medical College, 7 Kopernika St, 31-034, Kraków, Poland
| | - Marta Kaczor-Kamińska
- Chair of Medical Biochemistry, Jagiellonian University Medical College, 7 Kopernika St, 31-034, Kraków, Poland
| | - Ewa Jasek-Gajda
- Department of Histology, Jagiellonian University Medical College, 7 Kopernika St, 31-034, Kraków, Poland
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13
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Gleixner AM, Hutchison DF, Sannino S, Bhatia TN, Leak LC, Flaherty PT, Wipf P, Brodsky JL, Leak RK. N-Acetyl-l-Cysteine Protects Astrocytes against Proteotoxicity without Recourse to Glutathione. Mol Pharmacol 2017; 92:564-575. [PMID: 28830914 DOI: 10.1124/mol.117.109926] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 08/17/2017] [Indexed: 02/06/2023] Open
Abstract
N-acetyl-l-cysteine (NAC) exhibits protective properties in brain injury models and has undergone a number of clinical trials. Most studies of NAC have focused on neurons. However, neuroprotection may be complemented by the protection of astrocytes because healthier astrocytes can better support the viability of neurons. Here, we show that NAC can protect astrocytes against protein misfolding stress (proteotoxicity), the hallmark of neurodegenerative disorders. Although NAC is thought to be a glutathione precursor, NAC protected primary astrocytes from the toxicity of the proteasome inhibitor MG132 without eliciting any increase in glutathione. Furthermore, glutathione depletion failed to attenuate the protective effects of NAC. MG132 elicited a robust increase in the folding chaperone heat shock protein 70 (Hsp70), and NAC mitigated this effect. Nevertheless, three independent inhibitors of Hsp70 function ablated the protective effects of NAC, suggesting that NAC may help preserve Hsp70 chaperone activity and improve protein quality control without need for Hsp70 induction. Consistent with this view, NAC abolished an increase in ubiquitinated proteins in MG132-treated astrocytes. However, NAC did not affect the loss of proteasome activity in response to MG132, demonstrating that it boosted protein homeostasis and cell viability without directly interfering with the efficacy of this proteasome inhibitor. The thiol-containing molecules l-cysteine and d-cysteine both mimicked the protective effects of NAC, whereas the thiol-lacking molecule N-acetyl-S-methyl-l-cysteine failed to exert protection or blunt the rise in ubiquitinated proteins. Collectively, these findings suggest that the thiol group in NAC is required for its effects on glial viability and protein quality control.
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Affiliation(s)
- Amanda M Gleixner
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Daniel F Hutchison
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Sara Sannino
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Tarun N Bhatia
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Lillian C Leak
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Patrick T Flaherty
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Peter Wipf
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Jeffrey L Brodsky
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
| | - Rehana K Leak
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania (A.M.G., D.F.H., T.N.B., L.C.L., P.T.F., R.K.L.); and Departments of Biological Sciences (S.S., J.L.B.) and Chemistry and Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania (P.W.)
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14
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Hydrogen sulfide in cancer: Friend or foe? Nitric Oxide 2015; 50:38-45. [PMID: 26297862 DOI: 10.1016/j.niox.2015.08.004] [Citation(s) in RCA: 145] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 07/26/2015] [Accepted: 08/17/2015] [Indexed: 01/07/2023]
Abstract
Hydrogen sulfide (H2S) is the third gaseous signaling molecule that plays important roles in cancer biological processes. Recent studies indicate that H2S has both pro-cancer and anti-cancer effects. Endogenous H2S can exert pro-cancer functions through induction of angiogenesis regulation of mitochondrial bioenergetics, acceleration of cell cycle progression, and anti-apoptosis mechanisms. Thus, the inhibition of the production of H2S in cancer cells may be a new cancer treatment strategy. In contrast to the pro-cancer effect of H2S, relatively high concentrations of exogenous H2S could suppress the growth of cancer cells by inducing uncontrolled intracellular acidification, inducing cell cycle arrest, and promoting apoptosis. Therefore, H2S donors and H2S-releasing hybrids could be designed and developed as novel anti-cancer drugs. In this review, the production and metabolism of H2S in cancer cells are summarized and the role and mechanism of H2S in cancer development and progression are further discussed.
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15
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Is development of high-grade gliomas sulfur-dependent? Molecules 2014; 19:21350-62. [PMID: 25532835 PMCID: PMC6270701 DOI: 10.3390/molecules191221350] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Revised: 12/04/2014] [Accepted: 12/12/2014] [Indexed: 01/23/2023] Open
Abstract
We characterized γ-cystathionase, rhodanese and 3-mercaptopyruvate sulfurtransferase activities in various regions of human brain (the cortex, thalamus, hypothalamus, hippocampus, cerebellum and subcortical nuclei) and human gliomas with II to IV grade of malignancy (according to the WHO classification). The human brain regions, as compared to human liver, showed low γ-cystathionase activity. The activity of rhodanese was also much lower and it did not vary significantly between the investigated brain regions. The activity of 3-mercaptopyruvate sulfurtransferase was the highest in the thalamus, hypothalamus and subcortical nuclei and essentially the same level of sulfane sulfur was found in all the investigated brain regions. The investigations demonstrated that the level of sulfane sulfur in gliomas with the highest grades was high in comparison to various human brain regions, and was correlated with a decreased activity of γ-cystathionase, 3-mercaptopyruvate sulfurtransferase and rhodanese. This can suggest sulfane sulfur accumulation and points to its importance for malignant cell proliferation and tumor growth. In gliomas with the highest grades of malignancy, despite decreased levels of total free cysteine and total free glutathione, a high ratio of GSH/GSSG was maintained, which is important for the process of malignant cells proliferation. A high level of sulfane sulfur and high GSH/GSSG ratio could result in the elevated hydrogen sulfide levels. Because of the disappearance of γ-cystathionase activity in high-grade gliomas, it seems to be possible that 3-mercaptopyruvate sulfurtransferase could participate in hydrogen sulfide production. The results confirm sulfur dependence of malignant brain tumors.
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Sanokawa-Akakura R, Ostrakhovitch EA, Akakura S, Goodwin S, Tabibzadeh S. A H2S-Nampt dependent energetic circuit is critical to survival and cytoprotection from damage in cancer cells. PLoS One 2014; 9:e108537. [PMID: 25248148 PMCID: PMC4172766 DOI: 10.1371/journal.pone.0108537] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 08/27/2014] [Indexed: 11/18/2022] Open
Abstract
We recently demonstrated that cancer cells that recover from damage exhibit increased aerobic glycolysis, however, the molecular mechanism by which cancer cells survive the damage and show increased aerobic glycolysis remains unknown. Here, we demonstrate that diverse cancer cells that survive hypoxic or oxidative damage show rapid cell proliferation, and develop tolerance to damage associated with increased production of hydrogen sulfide (H2S) which drives up-regulation of nicotinamide phosphoribosyltransferase (Nampt). Consistent with existence of a H2S-Nampt energetic circuit, in damage recovered cancer cells, H2S, Nampt and ATP production exhibit a significant correlation. Moreover, the treatment of cancer cells with H2S donor, NaHS, coordinately increases Nampt and ATP levels, and protects cells from drug induced damage. Inhibition of cystathionine beta synthase (CBS) or cystathionase (CTH), enzymes which drive generation of H2S, decreases Nampt production while suppression of Nampt pathway by FK866, decreases H2S and ATP levels. Damage recovered cells isolated from tumors grown subcutaneously in athymic mice also show increased production of H2S, Nampt and ATP levels, associated with increased glycolysis and rapid proliferation. Together, these data show that upon recovery from potential lethal damage, H2S-Nampt directs energy expenditure and aerobic glycolysis in cancer cells, leads to their exponential growth, and causes a high degree of tolerance to damage. Identification of H2S-Nampt as a pathway responsible for induction of damage tolerance in cancer cells may underlie resistance to therapy and offers the opportunity to target this pathway as a means in treatment of cancer.
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Affiliation(s)
- Reiko Sanokawa-Akakura
- Frontiers in Bioscience Research Institute in Aging and Cancer, Irvine, California, United States of America
| | - Elena A. Ostrakhovitch
- Frontiers in Bioscience Research Institute in Aging and Cancer, Irvine, California, United States of America
| | - Shin Akakura
- Frontiers in Bioscience Research Institute in Aging and Cancer, Irvine, California, United States of America
| | - Scott Goodwin
- Dept of Radiological Sciences, University of California Irvine, Irvine, California, United States of America
| | - Siamak Tabibzadeh
- Frontiers in Bioscience Research Institute in Aging and Cancer, Irvine, California, United States of America
- Dept of Radiological Sciences, University of California Irvine, Irvine, California, United States of America
- * E-mail:
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Ramalho RT, Aydos RD, Schettert I, Cassino PC. Histopathological evaluation of tumor necrosis and volume after cyanogenic chemotherapy. Acta Cir Bras 2014; 29 Suppl 2:38-42. [DOI: 10.1590/s0102-8650201400140008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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18
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Ramalho RT, Aydos RD, Schettert I, Assis PVD, Cassino PC. Sulfane sulfur deficiency in malignant cells, increasing the inhibiting action of acetone cyanohydrin in tumor growth. Acta Cir Bras 2013; 28:728-32. [DOI: 10.1590/s0102-86502013001000007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Accepted: 09/12/2013] [Indexed: 11/22/2022] Open
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19
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Li Q, Lancaster JR. Chemical foundations of hydrogen sulfide biology. Nitric Oxide 2013; 35:21-34. [PMID: 23850631 DOI: 10.1016/j.niox.2013.07.001] [Citation(s) in RCA: 204] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 06/22/2013] [Accepted: 07/02/2013] [Indexed: 12/16/2022]
Abstract
Following nitric oxide (nitrogen monoxide) and carbon monoxide, hydrogen sulfide (or its newer systematic name sulfane, H2S) became the third small molecule that can be both toxic and beneficial depending on the concentration. In spite of its impressive therapeutic potential, the underlying mechanisms for its beneficial effects remain unclear. Any novel mechanism has to obey fundamental chemical principles. H2S chemistry was studied long before its biological relevance was discovered, however, with a few exceptions, these past works have received relatively little attention in the path of exploring the mechanistic conundrum of H2S biological functions. This review calls attention to the basic physical and chemical properties of H2S, focuses on the chemistry between H2S and its three potential biological targets: oxidants, metals and thiol derivatives, discusses the applications of these basics into H2S biology and methodology, and introduces the standard terminology to this youthful field.
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Affiliation(s)
- Qian Li
- Department of Anesthesiology, University of Alabama at Birmingham, United States; Center for Free Radical Biology, University of Alabama at Birmingham, United States.
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20
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Abstract
SIGNIFICANCE An abundance of experimental evidence suggests that hydrogen sulfide (H(2)S) plays a prominent role in physiology and pathophysiology. Many targets exist for H(2)S therapy. The molecular targets of H(2)S include proteins, enzymes, transcription factors, and membrane ion channels. RECENT ADVANCES Novel H(2)S precursors are being synthesized and discovered that are capable of releasing H(2)S in a slow and sustained manner. This presents a novel and advantageous approach to H(2)S therapy for treatment of chronic conditions associated with a decline in endogenous H(2)S, such as diabetes and cardiovascular disease. CRITICAL ISSUES While H(2)S is cytoprotective at physiological concentrations, it is not universally cytoprotective, as it appears to have pro-apoptotic actions in cancer cells and is well known to be toxic at supraphysiological concentrations. Many of the pleiotropic effects of H(2)S on health are associated with the inhibition of inflammation and upregulation of prosurvival pathways. The powerful anti-inflammatory, cytoprotective, immunomodulating, and trophic effects of H(2)S on the vast majority of normal cells seem to be mediated mainly by its actions as an extremely versatile direct and indirect antioxidant and free radical scavenger. While the overall effects of H(2)S on transformed (i.e., malignant) cells can be characterized as pro-oxidant and pro-apoptotic, they contrast sharply with the cytoprotective effects on most normal cells. FUTURE DIRECTIONS H(2)S has become a molecule of great interest, and several slow-releasing H(2)S prodrugs are currently under development. We believe that additional agents regulating H(2)S bioavailability will be developed during the next 10 years.
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Affiliation(s)
- Benjamin Lee Predmore
- Department of Surgery-Cardiothoracic Surgery, Emory University School of Medicine, Atlanta, Georgia, USA
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21
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Sulpizio M, Falone S, Amicarelli F, Marchisio M, Di Giuseppe F, Eleuterio E, Di Ilio C, Angelucci S. Molecular basis underlying the biological effects elicited by extremely low-frequency magnetic field (ELF-MF) on neuroblastoma cells. J Cell Biochem 2011; 112:3797-806. [DOI: 10.1002/jcb.23310] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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22
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Toohey JI. Sulfur signaling: is the agent sulfide or sulfane? Anal Biochem 2011; 413:1-7. [PMID: 21303647 DOI: 10.1016/j.ab.2011.01.044] [Citation(s) in RCA: 213] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Revised: 01/28/2011] [Accepted: 01/31/2011] [Indexed: 12/31/2022]
Affiliation(s)
- John I Toohey
- Cytoregulation Research, Elgin, Ontario, Canada K0G 1E0.
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Jurkowska H, Placha W, Nagahara N, Wróbel M. The expression and activity of cystathionine-γ-lyase and 3-mercaptopyruvate sulfurtransferase in human neoplastic cell lines. Amino Acids 2010; 41:151-8. [PMID: 20446008 DOI: 10.1007/s00726-010-0606-3] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2010] [Accepted: 04/17/2010] [Indexed: 10/19/2022]
Abstract
The expression and activity of cystathionine γ-lyase (CST) and 3-mercaptopyruvate sulfurtransferase (MPST) were investigated in the human neoplastic cells lines: astrocytoma U373, neuroblastoma SH-SY5Y, melanoma A375, and melanoma WM35. Gene expression analysis demonstrated that the investigated neoplastic cells showed the expression of MPST and what is particularly interesting, the expression of CST. The presence of CST in these cells was confirmed using RT-PCR and western blot analysis. However, in U373 cells, a very low activity of CST was detected. In all the investigated cell lines, the activity of MPST was higher than that of CST, which suggests that in these cells, the main pathway of sulfane sulfur formation is the MPST-catalyzed reaction. RP-HPLC analysis showed a large disparity between the level of cystathionine and GSH in the investigated neoplastic cells. In SH-SY5Y cells, the low level of GSH and low GSH/GSSG ratio corresponded with the highest CST activity. Further investigations could aim at verifying whether the stimulation of CST, at the level of protein or gene expression, could change the proliferation of neoplastic cells.
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Potential therapeutic advantage of ribose-cysteine in the inhibition of astrocytoma cell proliferation. Amino Acids 2010; 41:131-9. [DOI: 10.1007/s00726-010-0593-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2009] [Accepted: 04/02/2010] [Indexed: 02/07/2023]
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25
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Li X, Bazer FW, Gao H, Jobgen W, Johnson GA, Li P, McKnight JR, Satterfield MC, Spencer TE, Wu G. Amino acids and gaseous signaling. Amino Acids 2009; 37:65-78. [DOI: 10.1007/s00726-009-0264-5] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2009] [Accepted: 02/12/2009] [Indexed: 01/08/2023]
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26
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Ishigami M, Hiraki K, Umemura K, Ogasawara Y, Ishii K, Kimura H. A source of hydrogen sulfide and a mechanism of its release in the brain. Antioxid Redox Signal 2009; 11:205-14. [PMID: 18754702 DOI: 10.1089/ars.2008.2132] [Citation(s) in RCA: 376] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Hydrogen sulfide (H2S) is recognized as a neuromodulator as well as neuroprotectant in the brain. H2S can be produced from cysteine by enzymes such as cystathionine beta-synthase. However, a mechanism for releasing H2S under physiologic conditions has not been identified. Here we show that H2S is released from bound sulfur, an intracellular store of sulfur, in neurons and astrocytes of mice and rats in the presence of physiologic concentrations of endogenous reducing substances glutathione and cysteine. The highest pH to release H2S from another sulfur store, acid-labile sulfur, which is localized mainly in mitochondria, is 5.4. Because mitochondria are not in the acidic condition, acid-labile sulfur may not be a physiologic source of H2S. Free H2S is immediately absorbed and stored as bound sulfur. Our novel method, using silver particles to measure free H2S, shows that free H2S is maintained at a low level in basal conditions. Alkalinization of the cytoplasm is required for effective release of H2S from bound sulfur, and this condition is achieved in astrocytes by the high concentrations of extracellular K+ that are normally present when nearby neurons are excited. These data present a new perspective on the regulation of H2S in the brain.
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Affiliation(s)
- Mari Ishigami
- National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
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