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Claßen R, Diener M, Pouokam E. Gasotransmitters do not prevent changes in transepithelial ion transport induced by hypoxia followed by reoxygenation. J Basic Clin Physiol Pharmacol 2024; 35:61-70. [PMID: 38263911 DOI: 10.1515/jbcpp-2023-0034] [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: 02/06/2023] [Accepted: 12/28/2023] [Indexed: 01/25/2024]
Abstract
OBJECTIVES How gaseous signalling molecules affect ion transport processes contributing to the physiological functions of the gastrointestinal tract under hypoxic conditions still needs to be clarified. The objective of the present study was to characterize the impact of gaseous signalling molecules on parameters of colonic ion transport during a hypoxia/reoxygenation cycle and the remaining secretory capacity of the epithelium after such a cycle. METHODS Short-circuit current (Isc) and tissue conductance (Gt) recordings in Ussing chamber experiments were performed on rat colon samples using CORM-2 (putative CO donor; 35 and 350 µM), sodium nitroprusside (NO donor; 100 µM), NaHS (fast H2S donor; 10 - 1,000 µM), GYY 4137 (slow H2S donor; 50 µM) and Angeli's salt (HNO donor; 100 µM) as donors for gasotransmitters. Inhibition of endogenous synthesis of H2S was operated by inhibitors of cystathionin-γ-lyase, i.e. dl-propargylglycine (1 mM) or β-cyano-l-alanine (5 mM), and the inhibitor of cystathionine-β-synthase, amino-oxyacetate (5 mM). RESULTS The fast gasotransmitter donors NaHS, sodium nitroprusside and Angeli's salt, administered 5 min before the onset of hypoxia, induced an increase in Isc. The response to the subsequently applied hypoxia was characterized by a decrease in Isc, which tended to be reduced only in the presence of the lowest concentration of NaHS (10 µM) tested. Reoxygenation resulted in a slow increase in Isc, which was unaffected by all donors or inhibitors tested. The stable acetylcholine derivative carbachol (50 µM) was administered at the end of each hypoxia/reoxygenation cycle to test the secretory capacity of the epithelium. Pretreatment of the tissue with the putative CO donor CORM-2 suppressed the secretory response induced by carbachol. The same was observed when cystathionin-γ-lyase and cystathionin-γ-synthase were inhibited simultaneously. Under both conditions, Gt drastically increased suggesting an impaired tissue integrity. CONCLUSIONS The present results demonstrate that none of the exogenous gasotransmitter releasing drugs significantly ameliorated the changes in epithelial ion transport during the hypoxia/reoxygenation cycle ex vivo. In contrast, the putative CO donor CORM-2 exerted a toxic effect on the epithelium. The endogenous production of H2S, however, seems to have a protective effect on the mucosal integrity and the epithelial transport functions, which - when inhibited - leads to a loss of the secretory ability of the mucosa. This observation together with the trend for improvement observed with a low concentration of the H2S donor NaHS suggests a moderate protective role of low concentrations of H2S under hypoxic conditions.
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Affiliation(s)
- Rebecca Claßen
- Institute for Veterinary Physiology and Biochemistry, Justus-Liebig-Universitat Giessen, Giessen, Germany
| | - Martin Diener
- Institute for Veterinary Physiology and Biochemistry, Justus-Liebig-Universitat Giessen, Giessen, Germany
| | - Ervice Pouokam
- Institute for Veterinary Physiology and Biochemistry, Justus-Liebig-Universitat Giessen, Giessen, Germany
- Department of Human Medicine, MSB Medical School Berlin, Rüdesheimer Str. 50, 14197 Berlin, Germany
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Tsai KF, Shen CJ, Cheung CW, Wang TL, Chow LWC, Leung YM, Wong KL. Lipotoxicity in human lung alveolar type 2 A549 cells: Mechanisms and protection by tannic acid. CHINESE J PHYSIOL 2021; 64:289-297. [PMID: 34975122 DOI: 10.4103/cjp.cjp_68_21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Palmitic acid (PA) is a saturated free fatty acid which, when being excessive, accounts for lipotoxicity. Using human lung A549 cells as a model for lung alveolar type 2 epithelial cells, we found that challenge of A549 cells with PA resulted in apoptotic cell death, as reflected by positive annexin V and PI staining, and also appearance of cleaved caspase-3. PA treatment also caused depletion of intracellular Ca2+ store, endoplasmic reticulum (ER) stress, and oxidative stress. Tannic acid (TA), a polyphenol present in wines and many beverages, alleviated PA-induced ER stress, oxidative stress and apoptotic death. Thus, our results suggest PA lipotoxicity in lung alveolar type 2 epithelial cells could be protected by TA.
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Affiliation(s)
- Kun-Feng Tsai
- Gastroenterology and Hepatology Section, Department of Internal Medicine, An Nan Hospital, China Medical University; Department of Medical Sciences Industry, Chang Jung Christian University, Tainan, Taiwan
| | - Chen-Jung Shen
- Endocrinology and Metabolism Section, Department of Internal Medicine, An Nan Hospital, China Medical University, Tainan, Taiwan
| | - Chi-Wai Cheung
- Department of Anesthesiology, University of Hong Kong, China
| | - Tzong-Luen Wang
- School of Medicine, Fu-Jen Catholic University; Department of Emergency Medicine, Fu-Jen Catholic University Hospital, Taipei, Taiwan
| | - Louis W C Chow
- State Key Laboratory of Quality Research in Chinese Medicines, Macau University of Science and Technology, Taipa, Macau; UNIMED Medical Institute, Hong Kong; Organisation for Oncology and Translational Research, Hong Kong, China
| | - Yuk-Man Leung
- Department of Physiology, China Medical University, Taichung, Taiwan
| | - Kar-Lok Wong
- Department of Anesthesiology, University of Hong Kong, China; Department of Anesthesiology, Kuang Tien General Hospital, Shalu, Taichung, Taiwan
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3
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Xu JW, Gao DD, Peng L, Qiu ZE, Ke LJ, Zhu YX, Zhang YL, Zhou WL. The gasotransmitter hydrogen sulfide inhibits transepithelial anion secretion of pregnant mouse endometrial epithelium. Nitric Oxide 2019; 90:37-46. [PMID: 31175932 DOI: 10.1016/j.niox.2019.05.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 05/24/2019] [Accepted: 05/29/2019] [Indexed: 01/08/2023]
Abstract
Endometrial epithelium exhibits a robust ion transport activity required for dynamical regulation of uterine fluid environment and thus embryo implantation. However, there still lacks a thorough understanding of the ion transport processes and regulatory mechanism in peri-implantation endometrial epithelium. As a gaseous signaling molecule or gasotransmitter, hydrogen sulfide (H2S) regulates a myriad of cellular and physiological processes in various tissues, including the modulation of ion transport proteins in epithelium. This study aimed to investigate the effects of H2S on ion transport across mouse endometrial epithelium and its possible role in embryo implantation. The existence of endogenous H2S in pregnant mouse uterus was tested by the detection of two key H2S-generating enzymes and measurement of H2S production rate in tissue homogenates. Transepithelial ion transport processes were electrophysiologically assessed in Ussing chambers on early pregnant mouse endometrial epithelial layers, demonstrating that H2S suppressed the anion secretion by blocking cystic fibrosis transmembrane conductance regulator (CFTR). H2S increased intracellular Cl- concentration ([Cl-]i) in mouse endometrial epithelial cells, which was abolished by pretreatment with the CFTR selective inhibitor CFTRinh-172. The cAMP level in mouse endometrial epithelial cells was not affected by H2S, indicating that H2S blocked CFTR in a cAMP-independent way. In vivo study showed that interference with H2S synthesis impaired embryo implantation. In conclusion, our study demonstrated that H2S inhibits the transepithelial anion secretion of early pregnant mouse endometrial epithelium via blockade of CFTR, contributing to the preparation for embryo implantation.
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Affiliation(s)
- Jia-Wen Xu
- School of Life Sciences, Sun Yat-sen University, 510006, No. 132, Waihuan Dong Road, Higher Education Mega Center, Guangzhou, China
| | - Dong-Dong Gao
- School of Life Sciences, Sun Yat-sen University, 510006, No. 132, Waihuan Dong Road, Higher Education Mega Center, Guangzhou, China
| | - Lei Peng
- School of Life Sciences, Sun Yat-sen University, 510006, No. 132, Waihuan Dong Road, Higher Education Mega Center, Guangzhou, China
| | - Zhuo-Er Qiu
- School of Life Sciences, Sun Yat-sen University, 510006, No. 132, Waihuan Dong Road, Higher Education Mega Center, Guangzhou, China
| | - Li-Jiao Ke
- School of Life Sciences, Sun Yat-sen University, 510006, No. 132, Waihuan Dong Road, Higher Education Mega Center, Guangzhou, China
| | - Yun-Xin Zhu
- School of Life Sciences, Sun Yat-sen University, 510006, No. 132, Waihuan Dong Road, Higher Education Mega Center, Guangzhou, China
| | - Yi-Lin Zhang
- School of Life Sciences, Sun Yat-sen University, 510006, No. 132, Waihuan Dong Road, Higher Education Mega Center, Guangzhou, China.
| | - Wen-Liang Zhou
- School of Life Sciences, Sun Yat-sen University, 510006, No. 132, Waihuan Dong Road, Higher Education Mega Center, Guangzhou, China.
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Papu John AS, Kundu S, Pushpakumar S, Amin M, Tyagi SC, Sen U. Hydrogen sulfide inhibits Ca 2+-induced mitochondrial permeability transition pore opening in type-1 diabetes. Am J Physiol Endocrinol Metab 2019; 317:E269-E283. [PMID: 31039005 PMCID: PMC6732471 DOI: 10.1152/ajpendo.00251.2018] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 04/26/2019] [Accepted: 04/29/2019] [Indexed: 12/29/2022]
Abstract
Hydrogen sulfide (H2S) attenuates N-methyl-d-aspartate receptor-R1 (NMDA-R1) and mitigates diabetic renal damage; however, the molecular mechanism is not well known. Whereas NMDA-R1 facilitates Ca2+ permeability, H2S is known to inhibit L-type Ca2+ channel. High Ca2+ activates cyclophilin D (CypD), a gatekeeper protein of mitochondrial permeability transition pore (MPTP), thus facilitating molecular exchange between matrix and cytoplasm causing oxidative outburst and cell death. We tested the hypothesis of whether NMDA-R1 mediates Ca2+ influx causing CypD activation and MPTP opening leading to oxidative stress and renal injury in diabetes. We also tested whether H2S treatment blocks Ca2+ channel and thus inhibits CypD and MPTP opening to prevent renal damage. C57BL/6J and Akita (C57BL/6J-Ins2Akita) mice were treated without or with H2S donor GYY4137 (0.25 mg·kg-1·day-1 ip) for 8 wk. In vitro studies were performed using mouse glomerular endothelial cells. Results indicated that low levels of H2S and increased expression of NMDA-R1 in diabetes induced Ca2+ permeability, which was ameliorated by H2S treatment. We observed cytosolic Ca2+ influx in hyperglycemic (HG) condition along with mitochondrial-CypD activation, increased MPTP opening, and oxidative outburst, which were mitigated with H2S treatment. Renal injury biomarker KIM-1 was upregulated in HG conditions and normalized following H2S treatment. Inhibition of NMDA-R1 by pharmacological blocker MK-801 revealed similar results. We conclude that NMDA-R1-mediated Ca2+ influx in diabetes induces MPTP opening via CypD activation leading to increased oxidative stress and renal injury, and H2S protects diabetic kidney from injury by blocking mitochondrial Ca2+ permeability through NMDA-R1 pathway.
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Affiliation(s)
- A Sashi Papu John
- Department of Physiology, University of Louisville School of Medicine , Louisville, Kentucky
| | - Sourav Kundu
- Department of Physiology, University of Louisville School of Medicine , Louisville, Kentucky
| | - Sathnur Pushpakumar
- Department of Physiology, University of Louisville School of Medicine , Louisville, Kentucky
| | - Matthew Amin
- Department of Physiology, University of Louisville School of Medicine , Louisville, Kentucky
| | - Suresh C Tyagi
- Department of Physiology, University of Louisville School of Medicine , Louisville, Kentucky
| | - Utpal Sen
- Department of Physiology, University of Louisville School of Medicine , Louisville, Kentucky
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5
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Perniss A, Preiss K, Nier M, Althaus M. Hydrogen sulfide stimulates CFTR in Xenopus oocytes by activation of the cAMP/PKA signalling axis. Sci Rep 2017; 7:3517. [PMID: 28615646 PMCID: PMC5471219 DOI: 10.1038/s41598-017-03742-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Accepted: 05/05/2017] [Indexed: 12/27/2022] Open
Abstract
Hydrogen sulfide (H2S) has been recognized as a signalling molecule which affects the activity of ion channels and transporters in epithelial cells. The cystic fibrosis transmembrane conductance regulator (CFTR) is an epithelial anion channel and a key regulator of electrolyte and fluid homeostasis. In this study, we investigated the regulation of CFTR by H2S. Human CFTR was heterologously expressed in Xenopus oocytes and its activity was electrophysiologically measured by microelectrode recordings. The H2S-forming sulphur salt Na2S as well as the slow-releasing H2S-liberating compound GYY4137 increased transmembrane currents of CFTR-expressing oocytes. Na2S had no effect on native, non-injected oocytes. The effect of Na2S was blocked by the CFTR inhibitor CFTR_inh172, the adenylyl cyclase inhibitor MDL 12330A, and the protein kinase A antagonist cAMPS-Rp. Na2S potentiated CFTR stimulation by forskolin, but not that by IBMX. Na2S enhanced CFTR stimulation by membrane-permeable 8Br-cAMP under inhibition of adenylyl cyclase-mediated cAMP production by MDL 12330A. These data indicate that H2S activates CFTR in Xenopus oocytes by inhibiting phosphodiesterase activity and subsequent stimulation of CFTR by cAMP-dependent protein kinase A. In epithelia, an increased CFTR activity may correspond to a pro-secretory response to H2S which may be endogenously produced by the epithelium or H2S-generating microflora.
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Affiliation(s)
- Alexander Perniss
- Institute for Animal Physiology, Justus-Liebig-University, Giessen, Germany.,Institute for Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
| | - Kathrin Preiss
- Institute for Animal Physiology, Justus-Liebig-University, Giessen, Germany
| | - Marcel Nier
- Institute for Animal Physiology, Justus-Liebig-University, Giessen, Germany
| | - Mike Althaus
- Institute for Animal Physiology, Justus-Liebig-University, Giessen, Germany. .,School of Biology, Newcastle University, Newcastle upon Tyne, United Kingdom.
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6
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Schindele S, Pouokam E, Diener M. Hypoxia/Reoxygenation Effects on Ion Transport across Rat Colonic Epithelium. Front Physiol 2016; 7:247. [PMID: 27445839 PMCID: PMC4914783 DOI: 10.3389/fphys.2016.00247] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 06/03/2016] [Indexed: 12/04/2022] Open
Abstract
Ischemia causes severe damage in the gastrointestinal tract. Therefore, it is interesting to study how the barrier and transport functions of intestinal epithelium change under hypoxia and subsequent reoxygenation. For this purpose we simulated hypoxia and reoxygenation on mucosa-submucosa preparations from rat distal colon in Ussing chambers and on isolated crypts. Hypoxia (N2 gassing for 15 min) induced a triphasic change in short-circuit current (Isc): a transient decrease, an increase and finally a long-lasting fall below the initial baseline. During the subsequent reoxygenation phase, Isc slightly rose to values above the initial baseline. Tissue conductance (Gt) showed a biphasic increase during both the hypoxia and the reoxygenation phases. Omission of Cl− or preincubation of the tissue with transport inhibitors revealed that the observed changes in Isc represented changes in Cl− secretion. The radical scavenger trolox C reduced the Isc response during hypoxia, but failed to prevent the rise of Isc during reoxygenation. All changes in Isc were Ca2+-dependent. Fura-2 experiments at loaded isolated colonic crypts revealed a slow increase of the cytosolic Ca2+ concentration during hypoxia and the reoxygenation phase, mainly caused by an influx of extracellular Ca2+. Surprisingly, no changes could be detected in the fluorescence of the superoxide anion-sensitive dye mitosox or the thiol-sensitive dye thiol tracker, suggesting a relative high capacity of the colonic epithelium (with its low O2 partial pressure even under physiological conditions) to deal with enhanced radical production during hypoxia/reoxygenation.
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Affiliation(s)
- Sabine Schindele
- Institute of Veterinary Physiology and Biochemistry, University Giessen Giessen, Germany
| | - Ervice Pouokam
- Institute of Veterinary Physiology and Biochemistry, University Giessen Giessen, Germany
| | - Martin Diener
- Institute of Veterinary Physiology and Biochemistry, University Giessen Giessen, Germany
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7
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Tomuschat C, O'Donnell AM, Coyle D, Dreher N, Kelly D, Puri P. Altered expression of ATP-sensitive K(+) channels in Hirschsprung's disease. J Pediatr Surg 2016; 51:948-52. [PMID: 27001456 DOI: 10.1016/j.jpedsurg.2016.02.060] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 02/26/2016] [Indexed: 01/09/2023]
Abstract
PURPOSE Hirschsprung's disease-associated enterocolitis (HAEC) is the most common cause of morbidity and mortality in Hirschsprung's disease (HSCR). Altered intestinal epithelial barrier function has been suggested to play a role in the causation of HAEC. In rodent experimental models of colitis, a decreased expression of K(ATP) channels (Subunits: Kir6.1/6.2 and SUR1/2) is reported. We designed this study to determine if K(ATP) channels exist within the human colon and to investigate the expression of different subunits in Hirschsprung's disease. METHODS We investigated Kir6.1, Kir6.2, SUR1, and SUR2 expression in ganglionic and aganglionic bowel of HD patients (n=5) and controls (n=5). Western blotting and confocal immunofluorescence were performed. MAIN RESULTS Western blot analysis revealed that Kir6.1, Kir6.2, SUR1, and SUR2 are strongly expressed in the normal human colon. Kir6.1, Kir6.2, SUR1, and SUR2 expression was significantly decreased in the aganglionic bowel compared to ganglionic bowel and controls. Kir6.1 and SUR1 expression were also significantly decreased in the ganglionic bowel of HSCR patients compared to controls. CONCLUSION We demonstrate for the first time the existence of K(ATP) channels in the human colon. The decreased K(ATP) channel expression in HSCR specimens suggests that an altered K(ATP) expression may interfere with intestinal epithelium barrier function and predispose to HAEC.
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Affiliation(s)
- Christian Tomuschat
- National Children's Research Centre, Our Lady's Children's Hospital, Crumlin, Dublin, Ireland
| | - Anne Marie O'Donnell
- National Children's Research Centre, Our Lady's Children's Hospital, Crumlin, Dublin, Ireland
| | - David Coyle
- National Children's Research Centre, Our Lady's Children's Hospital, Crumlin, Dublin, Ireland
| | - Nickolas Dreher
- National Children's Research Centre, Our Lady's Children's Hospital, Crumlin, Dublin, Ireland
| | - Danielle Kelly
- National Children's Research Centre, Our Lady's Children's Hospital, Crumlin, Dublin, Ireland
| | - Prem Puri
- National Children's Research Centre, Our Lady's Children's Hospital, Crumlin, Dublin, Ireland; School of Medicine and Medical Science and Conway Institute of Biomedical Research, University College, Dublin, Ireland.
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8
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Abstract
In recent years, it has become apparent that the gaseous pollutant, hydrogen sulphide (H2S) can be synthesised in the body and has a multitude of biological actions. This review summarizes some of the actions of this 'gasotransmitter' in influencing the smooth muscle that is responsible for controlling muscular activity of hollow organs. In the vasculature, while H2S can cause vasoconstriction by complex interactions with other biologically important gases, such as nitric oxide, the prevailing response is vasorelaxation. While most vasorelaxation responses occur by a direct action of H2S on smooth muscle cells, it has recently been proposed to be an endothelium-derived hyperpolarizing factor. H2S also promotes relaxation in other smooth muscle preparations including bronchioles, the bladder, gastrointestinal tract and myometrium, opening up the opportunity of exploiting the pharmacology of H2S in the treatment of conditions where smooth muscle tone is excessive. The original concept, that H2S caused smooth muscle relaxation by activating ATP-sensitive K(+) channels, has been supplemented with observations that H2S can also modify the activity of other potassium channels, intracellular pH, phosphodiesterase activity and transient receptor potential channels on sensory nerves. While the enzymes responsible for generating endogenous H2S are widely expressed in smooth muscle preparations, it is much less clear what the physiological role of H2S is in determining smooth muscle contractility. Clarification of this requires the development of potent and selective inhibitors of H2S-generating enzymes.
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Affiliation(s)
- William R Dunn
- Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, United Kingdom.
| | - Stephen P H Alexander
- Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, United Kingdom
| | - Vera Ralevic
- Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, United Kingdom
| | - Richard E Roberts
- Pharmacology Research Group, School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, United Kingdom
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Epithelial Electrolyte Transport Physiology and the Gasotransmitter Hydrogen Sulfide. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2016; 2016:4723416. [PMID: 26904165 PMCID: PMC4745330 DOI: 10.1155/2016/4723416] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 12/17/2015] [Indexed: 11/18/2022]
Abstract
Hydrogen sulfide (H2S) is a well-known environmental chemical threat with an unpleasant smell of rotten eggs. Aside from the established toxic effects of high-dose H2S, research over the past decade revealed that cells endogenously produce small amounts of H2S with physiological functions. H2S has therefore been classified as a "gasotransmitter." A major challenge for cells and tissues is the maintenance of low physiological concentrations of H2S in order to prevent potential toxicity. Epithelia of the respiratory and gastrointestinal tract are especially faced with this problem, since these barriers are predominantly exposed to exogenous H2S from environmental sources or sulfur-metabolising microbiota. In this paper, we review the cellular mechanisms by which epithelial cells maintain physiological, endogenous H2S concentrations. Furthermore, we suggest a concept by which epithelia use their electrolyte and liquid transport machinery as defence mechanisms in order to eliminate exogenous sources for potentially harmful H2S concentrations.
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10
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An emerging role for gasotransmitters in the control of breathing and ionic regulation in fish. J Comp Physiol B 2015; 186:145-59. [DOI: 10.1007/s00360-015-0949-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 11/04/2015] [Accepted: 11/25/2015] [Indexed: 10/22/2022]
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Hydrogen sulfide-induced itch requires activation of Cav3.2 T-type calcium channel in mice. Sci Rep 2015; 5:16768. [PMID: 26602811 PMCID: PMC4658482 DOI: 10.1038/srep16768] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 10/19/2015] [Indexed: 01/02/2023] Open
Abstract
The contributions of gasotransmitters to itch sensation are largely unknown. In this
study, we aimed to investigate the roles of hydrogen sulfide (H2S), a
ubiquitous gasotransmitter, in itch signaling. We found that intradermal injection
of H2S donors NaHS or Na2S, but not GYY4137 (a slow-releasing
H2S donor), dose-dependently induced scratching behavior in a
μ-opioid receptor-dependent and histamine-independent manner in mice.
Interestingly, NaHS induced itch via unique mechanisms that involved
capsaicin-insensitive A-fibers, but not TRPV1-expressing C-fibers that are
traditionally considered for mediating itch, revealed by depletion of
TRPV1-expressing C-fibers by systemic resiniferatoxin treatment. Moreover, local
application of capsaizapine (TRPV1 blocker) or HC-030031 (TRPA1 blocker) had no
effects on NaHS-evoked scratching. Strikingly, pharmacological blockade and
silencing of Cav3.2 T-type calcium channel by mibefradil, ascorbic acid,
zinc chloride or Cav3.2 siRNA dramatically decreased NaHS-evoked
scratching. NaHS induced robust alloknesis (touch-evoked itch), which was inhibited
by T-type calcium channels blocker mibefradil. Compound 48/80-induced itch was
enhanced by an endogenous precursor of H2S (L-cysteine) but attenuated by
inhibitors of H2S-producing enzymes cystathionine γ-lyase and
cystathionine β-synthase. These results indicated that H2S,
as a novel nonhistaminergic itch mediator, may activates Cav3.2 T-type
calcium channel, probably located at A-fibers, to induce scratching and alloknesis
in mice.
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12
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Magierowski M, Magierowska K, Kwiecien S, Brzozowski T. Gaseous mediators nitric oxide and hydrogen sulfide in the mechanism of gastrointestinal integrity, protection and ulcer healing. Molecules 2015; 20:9099-123. [PMID: 25996214 PMCID: PMC6272495 DOI: 10.3390/molecules20059099] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 04/29/2015] [Accepted: 05/13/2015] [Indexed: 12/16/2022] Open
Abstract
Nitric oxide (NO) and hydrogen sulfide (H2S) are known as biological messengers; they play an important role in human organism and contribute to many physiological and pathophysiological processes. NO is produced from l-arginine by constitutive NO synthase (NOS) and inducible NOS enzymatic pathways. This gaseous mediator inhibits platelet aggregation, leukocyte adhesion and contributes to the vessel homeostasis. NO is known as a vasodilatory molecule involved in control of the gastric blood flow (GBF) and the maintenance of gastric mucosal barrier integrity in either healthy gastric mucosa or that damaged by strong irritants. Biosynthesis of H2S in mammals depends upon two enzymes cystathionine-β-synthase and cystathionine γ-lyase. This gaseous mediator, similarly to NO and carbon monoxide, is involved in neuromodulation, vascular contractility and anti-inflammatory activities. For decades, H2S has been known to inhibit cytochrome c oxidase and reduce cell energy production. Nowadays it is generally considered to act through vascular smooth muscle ATP-dependent K+ channels, interacting with intracellular transcription factors and promote sulfhydration of protein cysteine moieties within the cell, but the mechanism of potential gastroprotective and ulcer healing properties of H2S has not been fully explained. The aim of this review is to compare current results of the studies concerning the role of H2S and NO in gastric mucosa protection and outline areas that may pose new opportunities for further development of novel therapeutic targets.
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Affiliation(s)
- Marcin Magierowski
- Department of Physiology, Jagiellonian University Medical College, Cracow 31-531, Poland.
| | - Katarzyna Magierowska
- Department of Physiology, Jagiellonian University Medical College, Cracow 31-531, Poland.
| | - Slawomir Kwiecien
- Department of Physiology, Jagiellonian University Medical College, Cracow 31-531, Poland.
| | - Tomasz Brzozowski
- Department of Physiology, Jagiellonian University Medical College, Cracow 31-531, Poland.
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13
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Kwong RWM, Perry SF. Hydrogen sulfide promotes calcium uptake in larval zebrafish. Am J Physiol Cell Physiol 2015; 309:C60-9. [PMID: 25948733 DOI: 10.1152/ajpcell.00053.2015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 05/04/2015] [Indexed: 11/22/2022]
Abstract
Hydrogen sulfide (H2S) can act as a signaling molecule for various ion channels and/or transporters; however, little is known about its potential involvement in Ca(2+) balance. Using developing zebrafish (Danio rerio) as an in vivo model system, the present study demonstrated that acute exposure to H2S donors increased Ca(2+) influx at 4 days postfertilization, while chronic (3-day) exposure caused a rise in whole body Ca(2+) levels. The mRNA expression of Ca(2+)-transport-related genes was unaffected by H2S exposure, suggesting that posttranscriptional modifications were responsible for the altered rates of Ca(2+) uptake. Indeed, treatment of fish with the protein kinase A inhibitor H-89 abolished the H2S-mediated stimulation of Ca(2+) influx, suggesting that H2S increased Ca(2+) influx by activating cAMP-protein kinase A pathways. Cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE) are two key enzymes in the endogenous synthesis of H2S. Using an antisense morpholino knockdown approach, we demonstrated that Ca(2+) influx was reduced in CBS isoform b (CBSb)- but not in CSE-deficient fish. Interestingly, the reduction in Ca(2+) influx in CBSb-deficient fish was observed only in fish that were acclimated to low-Ca(2+) water (i.e., 25 μM Ca(2+); control: 250 μM Ca(2+)). Similarly, mRNA expression of cbsb but not cse was increased in fish acclimated to low-Ca(2+) water. Results from whole-mount immunohistochemistry further revealed that CBSb was expressed in Na(+)-K(+)-ATPase-rich cells, which are implicated in Ca(2+) uptake in zebrafish larvae. Collectively, the present study suggests a novel role for H2S in promoting Ca(2+) influx, particularly in a low-Ca(2+) environment.
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Affiliation(s)
- Raymond W M Kwong
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Steve F Perry
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
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Agné AM, Baldin JP, Benjamin AR, Orogo-Wenn MC, Wichmann L, Olson KR, Walters DV, Althaus M. Hydrogen sulfide decreases β-adrenergic agonist-stimulated lung liquid clearance by inhibiting ENaC-mediated transepithelial sodium absorption. Am J Physiol Regul Integr Comp Physiol 2015; 308:R636-49. [PMID: 25632025 DOI: 10.1152/ajpregu.00489.2014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 01/19/2015] [Indexed: 01/11/2023]
Abstract
In pulmonary epithelia, β-adrenergic agonists regulate the membrane abundance of the epithelial sodium channel (ENaC) and, thereby, control the rate of transepithelial electrolyte absorption. This is a crucial regulatory mechanism for lung liquid clearance at birth and thereafter. This study investigated the influence of the gaseous signaling molecule hydrogen sulfide (H2S) on β-adrenergic agonist-regulated pulmonary sodium and liquid absorption. Application of the H2S-liberating molecule Na2S (50 μM) to the alveolar compartment of rat lungs in situ decreased baseline liquid absorption and abrogated the stimulation of liquid absorption by the β-adrenergic agonist terbutaline. There was no additional effect of Na2S over that of the ENaC inhibitor amiloride. In electrophysiological Ussing chamber experiments with native lung epithelia (Xenopus laevis), Na2S inhibited the stimulation of amiloride-sensitive current by terbutaline. β-adrenergic agonists generally increase ENaC abundance by cAMP formation and activation of PKA. Activation of this pathway by forskolin and 3-isobutyl-1-methylxanthine increased amiloride-sensitive currents in H441 pulmonary epithelial cells. This effect was inhibited by Na2S in a dose-dependent manner (5-50 μM). Na2S had no effect on cellular ATP concentration, cAMP formation, and activation of PKA. By contrast, Na2S prevented the cAMP-induced increase in ENaC activity in the apical membrane of H441 cells. H441 cells expressed the H2S-generating enzymes cystathionine-β-synthase, cystathionine-γ-lyase, and 3-mercaptopyruvate sulfurtransferase, and they produced H2S amounts within the employed concentration range. These data demonstrate that H2S prevents the stimulation of ENaC by cAMP/PKA and, thereby, inhibits the proabsorptive effect of β-adrenergic agonists on lung liquid clearance.
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Affiliation(s)
- Alisa M Agné
- Institute of Animal Physiology, Department of Molecular Cell Physiology, Justus-Liebig University, Giessen, Germany
| | - Jan-Peter Baldin
- Institute of Animal Physiology, Department of Molecular Cell Physiology, Justus-Liebig University, Giessen, Germany
| | - Audra R Benjamin
- Division of Clinical Sciences, St. George's University of London, London, United Kingdom
| | - Maria C Orogo-Wenn
- Division of Clinical Sciences, St. George's University of London, London, United Kingdom
| | - Lukas Wichmann
- Institute of Animal Physiology, Department of Molecular Cell Physiology, Justus-Liebig University, Giessen, Germany
| | - Kenneth R Olson
- Department of Physiology, Indiana University School of Medicine-South Bend, South Bend, Indiana; and
| | - Dafydd V Walters
- Division of Clinical Sciences, St. George's University of London, London, United Kingdom
| | - Mike Althaus
- Institute of Animal Physiology, Department of Molecular Cell Physiology, Justus-Liebig University, Giessen, Germany;
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Gil V, Parsons S, Gallego D, Huizinga J, Jimenez M. Effects of hydrogen sulphide on motility patterns in the rat colon. Br J Pharmacol 2014; 169:34-50. [PMID: 23297830 DOI: 10.1111/bph.12100] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 11/26/2012] [Accepted: 12/17/2012] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND AND PURPOSE Hydrogen sulphide (H2 S) is an endogenous gaseous signalling molecule with putative functions in gastrointestinal motility regulation. Characterization of H2 S effects on colonic motility is crucial to establish its potential use as therapeutic agent in the treatment of colonic disorders. EXPERIMENTAL APPROACH H2 S effects on colonic motility were characterized using video recordings and construction of spatio-temporal maps. Microelectrode and muscle bath studies were performed to investigate the mechanisms underlying H2 S effects. NaHS was used as the source of H2 S. KEY RESULTS Rhythmic propulsive motor complexes (RPMCs) and ripples were observed in colonic spatio-temporal maps. Serosal addition of NaHS concentration-dependently inhibited RPMCs. In contrast, NaHS increased amplitude of the ripples without changing their frequency. Therefore, ripples became the predominant motor pattern. Neuronal blockade with lidocaine inhibited RPMCs, which were restored after administration of carbachol. Subsequent addition of NaHS inhibited RPMCs. Luminal addition of NaHS did not modify motility patterns. NaHS inhibited cholinergic excitatory junction potentials, carbachol-induced contractions and hyperpolarized smooth muscle cells, but did not modify slow wave activity. CONCLUSIONS AND IMPLICATIONS H2 S modulated colonic motility inhibiting propulsive contractile activity and enhancing the amplitude of ripples, promoting mixing. Muscle hyperpolarization and inhibition of neurally mediated cholinergic responses contributed to the inhibitory effect on propulsive activity. H2 S effects were not related to changes in the frequency of slow wave activity originating in the network of interstitial cells of Cajal located near the submuscular plexus. Luminal H2 S did not modify colonic motility probably because of epithelial detoxification.
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Affiliation(s)
- V Gil
- Department of Cell Biology, Physiology and Immunology/Neuroscience Institute, Universitat Autònoma de Barcelona (UAB), Barcelona, Spain
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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: 163] [Impact Index Per Article: 16.3] [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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Chao CC, Chan P, Kuo CS, Gong CL, Cheng TH, Liu ZM, Shen PC, Huang CC, Leung YM. Protection of differentiated neuronal NG108-15 cells from P2X7 receptor-mediated toxicity by taurine. Pharmacol Rep 2014; 66:576-84. [PMID: 24948057 DOI: 10.1016/j.pharep.2014.01.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 01/07/2014] [Accepted: 01/13/2014] [Indexed: 01/23/2023]
Abstract
BACKGROUND Strong P2X7 receptor (P2X7R) activation causes Ca(2+) overload and consequent cell death. We previously showed that depletion of Ca(2+) stores and endoplasmic reticulum (ER) stress in differentiated NG108-15 neuronal cells contributed to P2X7R-mediated cytotoxicity. In this work, we assessed whether taurine (2-aminoethanesulfonic acid) could prevent this P2X7R-mediated cytotoxicity in this neuronal cell line. METHODS Cytotoxicity markers were assessed by MTT assay and Western blotting. Cytosolic Ca(2+) and mitochondrial Ca(2+) concentrations were measured microfluorimetrically using fura-2 and rhod-2, respectively. Intracellular reactive oxygen species (ROS) production was assayed by the indicator 2',7'-dichlorodihydrofluorescein diacetate. RESULTS Selective P2X7R agonist BzATP treatment causes neuronal cell death by causing cytosolic Ca(2+) overload, depletion of Ca(2+) stores, endoplasmic reticulum (ER) stress, and caspase-3 activation (cleaved caspase 3). Remarkably, taurine (10mM) pretreatment could prevent P2X7R-mediated neuronal cell death by blocking BzATP-mediated ER stress as determined by phosphorylated eukaryotic translation initiation factor 2α (peIF2α) and C/EBP-homologous protein (CHOP). However, taurine did not block BzATP-induced Ca(2+) overload and depletion of ER Ca(2+) stores. Interestingly, P2X7R activation did not result in mitochondrial Ca(2+) overload, nor did it affect mitochondrial membrane potential. BzATP-induced generation of intracellular reactive oxygen species (ROS) was prevented by taurine. CONCLUSIONS The neuroprotective effect by taurine is attributed to the suppression of P2X7R-mediated ER stress and ROS formation.
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Affiliation(s)
- Chia-Chia Chao
- Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan
| | - Paul Chan
- Division of Cardiology, Department of Medicine, Taipei Medical University Wan Fang Hospital, Taipei, Taiwan
| | - Chang-Shin Kuo
- Graduate Institute of Neural and Cognitive Sciences, China Medical University, Taichung, Taiwan
| | - Chi-Li Gong
- Department of Physiology, China Medical University, Taichung, Taiwan
| | - Tzu-Hurng Cheng
- Department of Biological Sciences and Technology, China Medical University, Taichung, Taiwan
| | - Zhong-Min Liu
- Department of Cardiovascular Surgery, Shanghai East Hospital, Tongji University, Shanghai, China
| | - Pei-Chen Shen
- Department of Cardiology, Shanghai East Hospital, Tongji University, Shanghai, China
| | - Chieh-Chen Huang
- Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan.
| | - Yuk-Man Leung
- Graduate Institute of Neural and Cognitive Sciences, China Medical University, Taichung, Taiwan.
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Moustafa A, Habara Y. Hydrogen sulfide regulates Ca(2+) homeostasis mediated by concomitantly produced nitric oxide via a novel synergistic pathway in exocrine pancreas. Antioxid Redox Signal 2014; 20:747-58. [PMID: 24138560 PMCID: PMC3910447 DOI: 10.1089/ars.2012.5108] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
AIM The present study was designed to explore the effects of hydrogen sulfide (H2S) on Ca(2+) homeostasis in rat pancreatic acini. RESULTS Sodium hydrosulfide (NaHS; an H2S donor) induced a biphasic increase in the intracellular Ca(2+) concentration ([Ca(2+)]i) in a dose-dependent manner. The NaHS-induced [Ca(2+)]i elevation persisted with an EC50 of 73.3 μM in the absence of extracellular Ca(2+) but was abolished by thapsigargin, indicating that both Ca(2+) entry and Ca(2+) release contributed to the increase. The [Ca(2+)]i increase was markedly inhibited in the presence of NG-monomethyl L-arginine or 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO), and diaminofluorescein-2/diaminofluorescein-2 triazole (DAF-2/DAF-2T) fluorometry demonstrated that nitric oxide (NO) was also produced by H2S in a dose-dependent manner with an EC50 of 64.8 μM, indicating that NO was involved in the H2S effect. The H2S-induced [Ca(2+)]i increase was inhibited by pretreatment with U73122, xestospongin C, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, KT5823, and GP2A, indicating that phospholipase C (PLC), the inositol 1,4,5-trisphosphate (IP3) receptor, soluble guanylate cyclase (sGC), protein kinase G (PKG), and Gq-protein play roles as intermediate components in the H2S-triggered intracellular signaling. INNOVATION To our knowledge, our study is the first one highlighting the effect of H2S on intracellular Ca(2+) dynamics in pancreatic acinar cells. Moreover, a novel cascade was presumed to function via the synergistic interaction between H2S and NO. CONCLUSION We conclude that H2S affects [Ca(2+)]i homeostasis that is mediated by H2S-evoked NO production via an endothelial nitric oxide synthase (eNOS)-NO-sGC-cyclic guanosine monophosphate-PKG-Gq-protein-PLC-IP3 pathway to induce Ca(2+) release, and this pathway is identical to the one we recently proposed for a sole effect of NO and the two gaseous molecules synergistically function to regulate Ca(2+) homeostasis.
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Affiliation(s)
- Amira Moustafa
- 1 Laboratory of Physiology, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University , Sapporo, Japan
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19
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Pouokam E, Bell A, Diener M. Actions of Angeli's salt, a nitroxyl (HNO) donor, on ion transport across mucosa—submucosa preparations from rat distal colon. Eur J Pharmacol 2013; 715:133-41. [DOI: 10.1016/j.ejphar.2013.05.031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 05/03/2013] [Accepted: 05/20/2013] [Indexed: 10/26/2022]
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Flannigan KL, Ferraz JGP, Wang R, Wallace JL. Enhanced synthesis and diminished degradation of hydrogen sulfide in experimental colitis: a site-specific, pro-resolution mechanism. PLoS One 2013; 8:e71962. [PMID: 23940796 PMCID: PMC3733965 DOI: 10.1371/journal.pone.0071962] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 07/06/2013] [Indexed: 11/18/2022] Open
Abstract
Hydrogen sulfide (H2S) is produced throughout the gastrointestinal tract, and it contributes to maintenance of mucosal integrity, resolution of inflammation, and repair of damaged tissue. H2S synthesis is elevated in inflamed and damaged colonic tissue, but the enzymatic sources of that synthesis are not completely understood. In the present study, the contributions of three enzymatic pathways to colonic H2S synthesis were determined, with tissues taken from healthy rats and rats with colitis. The ability of the colonic tissue to inactivate H2S was also determined. Colonic tissue from rats with hapten-induced colitis produced significantly more H2S than tissue from healthy controls. The largest source of the H2S synthesis was the pathway involving cysteine amino transferase and 3-mercaptopyruvate sulfurtransferase (an α-ketoglutarate-dependent pathway). Elevated H2S synthesis occurred specifically at sites of mucosal ulceration, and was not related to the extent of granulocyte infiltration into the tissue. Inactivation of H2S by colonic tissue occurred rapidly, and was significantly reduced at sites of mucosal ulceration. This correlated with a marked decrease in the expression of sulfide quinone reductase in these regions. Together, the increased production and decreased inactivation of H2S at sites of mucosal ulceration would result in higher H2S levels at these sites, which promotes of resolution of inflammation and repair of damaged tissue.
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Affiliation(s)
- Kyle L. Flannigan
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Jose G. P. Ferraz
- Inflammation Research Network, University of Calgary, Calgary, Alberta, Canada
| | - Rui Wang
- Department of Biology, Lakehead University, Thunder Bay, Ontario, Canada
| | - John L. Wallace
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, Ontario, Canada
- Inflammation Research Network, University of Calgary, Calgary, Alberta, Canada
- * E-mail:
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21
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Wu B, Teng H, Yang G, Wu L, Wang R. Hydrogen sulfide inhibits the translational expression of hypoxia-inducible factor-1α. Br J Pharmacol 2013; 167:1492-505. [PMID: 22831549 DOI: 10.1111/j.1476-5381.2012.02113.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND AND PURPOSE The accumulation of hypoxia-inducible factor-1α (HIF-1α) is under the influence of hydrogen sulfide (H(2) S), which regulates hypoxia responses. The regulation of HIF-1α accumulation by H(2) S has been shown, but the mechanisms for this effect are largely elusive and controversial. This study aimed at addressing the controversial mechanisms for and the functional importance of the interaction of H(2) S and HIF-1α protein. EXPERIMENTAL APPROACH HIF-1α protein levels and HIF-1α transcriptional activity were detected by Western blotting and luciferase assay. The mechanisms for H(2) S-regulated HIF-1α protein levels were determined using short interfering RNA transfection, co-immunoprecipitation and 7-methyl-GTP sepharose 4B pull-down assay. Angiogenic activity was evaluated using tube formation assay in EA.hy926 cells. KEY RESULTS The accumulation of HIF-1α protein under hypoxia (1% O(2) ) or hypoxia-mimetic conditions was reversed by sodium hydrosulfide (NaHS). This effect of NaHS was not altered after blocking the ubiquitin-proteasomal pathway for HIF-1α degradation; however, blockade of protein translation with cycloheximide abolished the effect of NaHS on the half-life of HIF-1α protein. Knockdown of eukaryotic translation initiation factor 2α (eIF2α) suppressed the effect of NaHS on HIF-1α protein accumulation under hypoxia. NaHS inhibited the expression of VEGF under hypoxia. It also decreased in vitro capillary tube formation and cell proliferation of EA.hy926 cells under hypoxia, but stimulated the tube formation under normoxia. CONCLUSIONS AND IMPLICATIONS H(2) S suppresses HIF-1α translation by enhancing eIF2α phosphorylation under hypoxia. The interaction of H(2) S and HIF-1α inhibits the angiogenic activity of vascular endothelial cells under hypoxia through the down-regulation of VEGF.
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Affiliation(s)
- Bo Wu
- Department of Pathophysiology, Harbin Medical University, Harbin, China Department of Biology, Lakehead University, Thunder Bay, ON, Canada
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22
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Park SJ, Kim TH, Lee SH, Ryu HY, Hong KH, Jung JY, Hwang GH, Lee SH. Expression levels of endogenous hydrogen sulfide are altered in patients with allergic rhinitis. Laryngoscope 2013; 123:557-63. [PMID: 23303708 DOI: 10.1002/lary.23466] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Revised: 04/04/2012] [Accepted: 05/04/2012] [Indexed: 11/06/2022]
Abstract
OBJECTIVES/HYPOTHESIS Hydrogen sulfide (H(2) S), the third endogenous gaseous transmitter, may be a crucial mediator in airway hyper-responsiveness and airway inflammation, including asthma. To elucidate the role of H(2) S in allergic rhinitis, the present study was undertaken to determine the level of expression of H(2) S in healthy nasal mucosa and mild and moderate/severe persistent allergic nasal mucosa as well as peripheral blood obtained from each patient. The expression and distribution pattern of the H(2) S-synthesizing enzymes cystathione γ-lyase (CSE) and cystathione β-synthase (CBS) were investigated in healthy and allergic nasal mucosa. STUDY DESIGN Controlled, prospective study. METHODS The concentration of H(2) S in nasal mucosa and plasma was determined by zinc trap spectrophotometry. The expression levels and patterns of distribution of CSE and CBS mRNA and proteins were evaluated using real time polymerase chain reaction, Western blot, and immunohistochemistry. RESULTS The levels of expression of H(2) S in nasal mucosa and plasma were increased in patients with mild and moderate/severe persistent allergic rhinitis compared with healthy controls. CSE was localized in vascular endothelium and surrounding muscles, and submucosal glands, whereas CBS was exclusively distributed in the superficial epithelium and submucosal glands. Their expression levels were increased in mild and moderate/severe persistent allergic rhinitis. CONCLUSIONS The current findings indicate that, in parallel with increased expression levels of CSE and CBS, H(2) S is upregulated in nasal mucosa and plasma of allergic patients. Based on localization of CSE and CBS, H(2) S may play multiple functions in human nasal mucosa, contributing to the development of allergic symptoms such as rhinorrhea, sneezing, and nasal stuffiness.
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Affiliation(s)
- Se Jin Park
- Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Korea University, Seoul, South Korea
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Pouokam E, Bader S, Brück B, Schmidt B, Diener M. ATP-sensitive K(+) channels in rat colonic epithelium. Pflugers Arch 2012; 465:865-77. [PMID: 23262522 DOI: 10.1007/s00424-012-1207-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 12/10/2012] [Accepted: 12/10/2012] [Indexed: 11/30/2022]
Abstract
ATP-sensitive K(+) (KATP) channels couple the metabolic state of a cell to its electrical activity. They consist of a hetero-octameric complex with pore-forming Kir6.x (Kir6.1, Kir6.2) and regulatory sulfonylurea receptor (SUR) subunits. Functional data indicate that KATP channels contribute to epithelial K(+) currents at colonic epithelia. However, their molecular identity and their properties are largely unknown. Therefore, changes in short-circuit current (I sc) induced by the KATP channel opener pinacidil (5 10(-4) mol l(-1)) were measured in Ussing chambers under control conditions and in the presence of different blockers of KATP channels. The channel subunits expressed by the colonic epithelium were identified by immunohistochemistry and by RT-PCR. The K(+) channel opener, when administered at the serosal side, induced an increase in I sc consistent with the induction of transepithelial Cl(-) secretion after activation of basolateral K(+) channels, whereas mucosal administration of pinacidil resulted in a negative I sc. The increase in I sc evoked by serosal pinacidil was inhibited by serosal administration of glibenclamide (5 10(-4) mol l(-1)) and gliclazide (10(-6) mol l(-1)), but was resistant even against a high concentration (10(-2) mol l(-1)) of tolbutamide. In contrast, none of these inhibitors (administered at the mucosal side) reduced significantly the negative I sc induced by mucosal pinacidil. Instead, pinacidil inhibited Cl(-) currents across apical Cl(-) channels in basolaterally depolarized epithelia indicating that the negative I sc induced by mucosal pinacidil is due to a transient inhibition of Cl(-) secretion. In mRNA prepared from isolated colonic crypts, messenger RNA for both pore-forming subunits, Kir6.1 and Kir6.2, and two regulatory subunits (SUR1 and SUR2B) was found. Expression within the colonic epithelium was confirmed for these subunits by immunohistochemistry. In consequence, KATP channels are present in the basolateral membrane of the colonic epithelium; their exact subunit composition, however, has still to be revealed.
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Affiliation(s)
- Ervice Pouokam
- Institute for Veterinary Physiology and Biochemistry, Justus-Liebig-University, Frankfurter Str. 100, Giessen, Germany
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Althaus M, Urness KD, Clauss WG, Baines DL, Fronius M. The gasotransmitter hydrogen sulphide decreases Na⁺ transport across pulmonary epithelial cells. Br J Pharmacol 2012; 166:1946-63. [PMID: 22352810 DOI: 10.1111/j.1476-5381.2012.01909.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND AND PURPOSE The transepithelial absorption of Na(+) in the lungs is crucial for the maintenance of the volume and composition of epithelial lining fluid. The regulation of Na(+) transport is essential, because hypo- or hyperabsorption of Na(+) is associated with lung diseases such as pulmonary oedema or cystic fibrosis. This study investigated the effects of the gaseous signalling molecule hydrogen sulphide (H(2) S) on Na(+) absorption across pulmonary epithelial cells. EXPERIMENTAL APPROACH Ion transport processes were electrophysiologically assessed in Ussing chambers on H441 cells grown on permeable supports at air/liquid interface and on native tracheal preparations of pigs and mice. The effects of H(2)S were further investigated on Na(+) channels expressed in Xenopus oocytes and Na(+) /K(+)-ATPase activity in vitro. Membrane abundance of Na(+) /K(+)-ATPase was determined by surface biotinylation and Western blot. Cellular ATP concentrations were measured colorimetrically, and cytosolic Ca(2+) concentrations were measured with Fura-2. KEY RESULTS H(2)S rapidly and reversibly inhibited Na(+) transport in all the models employed. H(2)S had no effect on Na(+) channels, whereas it decreased Na(+) /K(+)-ATPase currents. H(2)S did not affect the membrane abundance of Na(+) /K(+)-ATPase, its metabolic or calcium-dependent regulation, or its direct activity. However, H(2)S inhibited basolateral calcium-dependent K(+) channels, which consequently decreased Na(+) absorption by H441 monolayers. CONCLUSIONS AND IMPLICATIONS H(2) S impairs pulmonary transepithelial Na(+) absorption, mainly by inhibiting basolateral Ca(2+)-dependent K(+) channels. These data suggest that the H(2)S signalling system might represent a novel pharmacological target for modifying pulmonary transepithelial Na(+) transport.
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Affiliation(s)
- M Althaus
- Institute of Animal Physiology, Justus-Liebig University of Giessen, Giessen, Germany.
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Steidle J, Würner L, Diener M. Altered response to hydrogen sulphide during experimental colitis in rats. J Anim Physiol Anim Nutr (Berl) 2012; 97:942-50. [PMID: 22963333 DOI: 10.1111/jpn.12000] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Hydrogen sulphide (H2 S) is produced in the intestine by sulphate-reducing bacteria and during metabolism of L-cysteine within the mucosa. This gasotransmitter induces anion secretion by stimulating enteric neurons and by a direct effect on epithelial cells. As H2 S is discussed to exert both pro- and anti-inflammatory actions, we aimed to investigate the role of H2 S during experimental colitis by comparing the effects of blockade of H2 S-forming endogenous enzymes with the effect of a S-reduced diet to diminish microbial production of H2 S. Rectal application of trinitrobenzenesulfonic acid (TNBS) was used to induce chronic colitis. The level of inflammation was assessed macroscopically and histologically. In Ussing chamber experiments, colonic specimens from TNBS-treated animals exhibited a higher tissue conductance, that is, a higher epithelial permeability, and a slightly reduced basal short-circuit current (a measure of net ion transport) in relation to non-inflamed control tissue. Analgetic treatment with flupirtine, a central antinociceptive analgetic, did not interfere with the induction of the inflammatory response so that all animals were treated with flupirtine to reduce pain and distress during the development of colitis. The secretory response evoked by an exogenous H2 S donor, NaHS, was significantly decreased after induction of colitis, whereas the response to Ca(2+) - or cAMP-dependent secretagogues was unaltered. This downregulation was not observed in the colitis group fed on a S-reduced diet. The decreased NaHS response indicates a desensitization of the tissue by inflammation, which might be explained by an upregulation of colonic H2 S production as described in some models of inflammation.
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Affiliation(s)
- J Steidle
- Institute for Veterinary Physiology and Biochemistry, Justus-Liebig-University Giessen, Giessen, Germany
| | - L Würner
- Institute for Veterinary Physiology and Biochemistry, Justus-Liebig-University Giessen, Giessen, Germany
| | - M Diener
- Institute for Veterinary Physiology and Biochemistry, Justus-Liebig-University Giessen, Giessen, Germany
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Linden DR, Furne J, Stoltz GJ, Abdel-Rehim MS, Levitt MD, Szurszewski JH. Sulphide quinone reductase contributes to hydrogen sulphide metabolism in murine peripheral tissues but not in the CNS. Br J Pharmacol 2012; 165:2178-90. [PMID: 21950400 DOI: 10.1111/j.1476-5381.2011.01681.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND AND PURPOSE Hydrogen sulphide (H(2) S) is gaining acceptance as a gaseous signal molecule. However, mechanisms regarding signal termination are not understood. We used stigmatellin and antimycin A, inhibitors of sulphide quinone reductase (SQR), to test the hypothesis that the catabolism of H(2) S involves SQR. EXPERIMENTAL APPROACH H(2) S production and consumption were determined in living and intact mouse brain, liver and colonic muscularis externa using gas chromatography and HPLC. Expressions of SQR, ethylmalonic encephalopathy 1 (Ethe1) and thiosulphate transferase (TST; rhodanese) were determined by RT-PCR and immunohistochemistry. KEY RESULTS In the colonic muscularis externa, H(2) (35) S was catabolized to [(35) S]-thiosulphate and [(35) S]-sulphate, and stigmatellin reduced both the consumption of H(2) (35) S and formation of [(35) S]-thiosulphate. Stigmatellin also enhanced H(2) S release by the colonic muscularis externa. In the brain, catabolism of H(2) (35) S to [(35) S]-thiosulphate and [(35) S]-sulphate, which was stigmatellin-insensitive, partially accounted for H(2) (35) S consumption, while the remainder was captured as unidentified (35) S that was probably bound to proteins. Levels of mRNA encoding SQR were higher in the colonic muscularis externa and the liver than in the brain. CONCLUSIONS AND IMPLICATIONS These data support the concept that termination of endogenous H(2) S signalling in the colonic muscularis externa occurs via catabolism to thiosulphate and sulphate partially via a mechanism involving SQR. In the brain, it appears that H(2) S signal termination occurs partially through protein sequestration and partially through catabolism not involving SQR. As H(2) S has beneficial effects in animal models of human disease, we suggest that selective inhibition of SQR is an attractive target for pharmaceutical development.
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Affiliation(s)
- D R Linden
- Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, MN, USA.
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Althaus M. Gasotransmitters: novel regulators of epithelial na(+) transport? Front Physiol 2012; 3:83. [PMID: 22509167 PMCID: PMC3321473 DOI: 10.3389/fphys.2012.00083] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Accepted: 03/20/2012] [Indexed: 11/13/2022] Open
Abstract
The vectorial transport of Na(+) across epithelia is crucial for the maintenance of Na(+) and water homeostasis in organs such as the kidneys, lung, or intestine. Dysregulated Na(+) transport processes are associated with various human diseases such as hypertension, the salt-wasting syndrome pseudohypoaldosteronism type 1, pulmonary edema, cystic fibrosis, or intestinal disorders, which indicate that a precise regulation of epithelial Na(+) transport is essential. Novel regulatory signaling molecules are gasotransmitters. There are currently three known gasotransmitters: nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H(2)S). These molecules are endogenously produced in mammalian cells by specific enzymes and have been shown to regulate various physiological processes. There is a growing body of evidence which indicates that gasotransmitters may also regulate Na(+) transport across epithelia. This review will summarize the available data concerning NO, CO, and H(2)S dependent regulation of epithelial Na(+) transport processes and will discuss whether or not these mediators can be considered as true physiological regulators of epithelial Na(+) transport biology.
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Affiliation(s)
- Mike Althaus
- Institute of Animal Physiology, Justus Liebig University of Giessen Giessen, Germany
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Gil V, Gallego D, Jiménez M. Effects of inhibitors of hydrogen sulphide synthesis on rat colonic motility. Br J Pharmacol 2012; 164:485-98. [PMID: 21486289 DOI: 10.1111/j.1476-5381.2011.01431.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND AND PURPOSE The role of hydrogen sulphide (H₂S) as a putative endogenous signalling molecule in the gastrointestinal tract has not yet been established. We investigated the effect of D,L-propargylglycine (PAG), an inhibitor of cystathionine γ-lyase (CSE), amino-oxyacetic acid (AOAA) and hydroxylamine (HA), inhibitors of cystathionine β-synthase (CBS) on rat colonic motility. EXPERIMENTAL APPROACH Immunohistochemistry, H₂S production, microelectrode and organ bath recordings were performed on rat colonic samples without mucosa and submucosa to investigate the role of endogenous H₂S in motility. KEY RESULTS CSE and CBS were immunolocalized in the colon. H₂S was endogenously produced (15.6 ± 0.7 nmol·min⁻¹·g⁻¹ tissue) and its production was strongly inhibited by PAG (2 mM) and AOAA (2 mM). PAG (2 mM) caused smooth muscle depolarization and increased spontaneous motility. The effect was still recorded after incubation with tetrodotoxin (TTX, 1 µM) or N(ω) -nitro-L-arginine (L-NNA, 1 mM). AOAA (2 mM) caused a transient (10 min) increase in motility. In contrast, HA (10 µM) caused a 'nitric oxide-like effect', smooth muscle hyperpolarization and relaxation, which were antagonized by 1H-[1,2,4]oxadiazolo[4,3-α]quinoxalin-1-one (ODQ, 10 µM). Neither spontaneous nor induced inhibitory junction potentials were modified by AOAA or PAG. CONCLUSIONS AND IMPLICATIONS We demonstrated that H₂S is endogenously produced in the rat colon. PAG and AOAA effectively blocked H₂S production. Our data suggest that enzymatic production of H₂S regulates colonic motility and therefore H₂S ight be a third gaseous inhibitory signalling molecule in the gastrointestinal tract. However, possible non-specific effects of the inhibitors should be considered.
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Affiliation(s)
- V Gil
- Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona (UAB), Bellaterra, Spain
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Gil V, Gallego D, Jiménez M. Effects of inhibitors of hydrogen sulphide synthesis on rat colonic motility. Br J Pharmacol 2012. [PMID: 21486289 DOI: 10.1111/j.1476-5381.2011.01431.x/pdf] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND AND PURPOSE The role of hydrogen sulphide (H₂S) as a putative endogenous signalling molecule in the gastrointestinal tract has not yet been established. We investigated the effect of D,L-propargylglycine (PAG), an inhibitor of cystathionine γ-lyase (CSE), amino-oxyacetic acid (AOAA) and hydroxylamine (HA), inhibitors of cystathionine β-synthase (CBS) on rat colonic motility. EXPERIMENTAL APPROACH Immunohistochemistry, H₂S production, microelectrode and organ bath recordings were performed on rat colonic samples without mucosa and submucosa to investigate the role of endogenous H₂S in motility. KEY RESULTS CSE and CBS were immunolocalized in the colon. H₂S was endogenously produced (15.6 ± 0.7 nmol·min⁻¹·g⁻¹ tissue) and its production was strongly inhibited by PAG (2 mM) and AOAA (2 mM). PAG (2 mM) caused smooth muscle depolarization and increased spontaneous motility. The effect was still recorded after incubation with tetrodotoxin (TTX, 1 µM) or N(ω) -nitro-L-arginine (L-NNA, 1 mM). AOAA (2 mM) caused a transient (10 min) increase in motility. In contrast, HA (10 µM) caused a 'nitric oxide-like effect', smooth muscle hyperpolarization and relaxation, which were antagonized by 1H-[1,2,4]oxadiazolo[4,3-α]quinoxalin-1-one (ODQ, 10 µM). Neither spontaneous nor induced inhibitory junction potentials were modified by AOAA or PAG. CONCLUSIONS AND IMPLICATIONS We demonstrated that H₂S is endogenously produced in the rat colon. PAG and AOAA effectively blocked H₂S production. Our data suggest that enzymatic production of H₂S regulates colonic motility and therefore H₂S ight be a third gaseous inhibitory signalling molecule in the gastrointestinal tract. However, possible non-specific effects of the inhibitors should be considered.
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Affiliation(s)
- V Gil
- Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona (UAB), Bellaterra, Spain
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Pouokam E, Diener M. Modulation of ion transport across rat distal colon by cysteine. Front Physiol 2012; 3:43. [PMID: 22403551 PMCID: PMC3291876 DOI: 10.3389/fphys.2012.00043] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Accepted: 02/17/2012] [Indexed: 12/29/2022] Open
Abstract
The aim of this study was to identify the actions of stimulation of endogenous production of H(2)S by cysteine, the substrate for the two H(2)S-producing enzymes, cystathionine-β-synthase and cystathionine-γ-lyase, on ion transport across rat distal colon. Changes in short-circuit current (Isc) induced by cysteine were measured in Ussing chambers. Free cysteine caused a concentration-dependent, transient fall in Isc, which was sensitive to amino-oxyacetate and β-cyano-L-alanine, i.e., inhibitors of H(2)S-producing enzymes. In contrast, Na cysteinate evoked a biphasic change in Isc, i.e., an initial fall followed by a secondary increase, which was also reduced by these enzyme inhibitors. All responses were dependent on the presence of Cl(-) and inhibited by bumetanide, suggesting that free cysteine induces an inhibition of transcellular Cl(-) secretion, whereas Na cysteinate - after a transient inhibitory phase - activates anion secretion. The assumed reason for this discrepancy is a fall in the cytosolic pH induced by free cysteine, but not by Na cysteinate, as observed in isolated colonic crypts loaded with the pH-sensitive dye, BCECF. Intracellular acidification is known to inhibit epithelial K(+) channels. Indeed, after preinhibition of basolateral K(+) channels with tetrapentylammonium or Ba(2+), the negative Isc induced by free cysteine was reduced significantly. In consequence, stimulation of endogenous H(2)S production by Na cysteinate causes, after a short inhibitory response, a delayed activation of anion secretion, which is missing in the case of free cysteine, probably due to the cytosolic acidification. In contrast, diallyl trisulfide, which is intracellularly converted to H(2)S, only evoked a monophasic increase in Isc without the initial fall observed with Na cysteinate. Consequently, time course and amount of produced H(2)S seem to strongly influence the functional response of the colonic epithelium evoked by this gasotransmitter.
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Affiliation(s)
- Ervice Pouokam
- Institute for Veterinary Physiology and Biochemistry, University Giessen Giessen, Germany
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Pouokam E, Steidle J, Diener M. Regulation of Colonic Ion Transport by Gasotransmitters. Biol Pharm Bull 2011; 34:789-93. [DOI: 10.1248/bpb.34.789] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Ervice Pouokam
- Institute for Veterinary Physiology, University of Giessen
| | - Julia Steidle
- Institute for Veterinary Physiology, University of Giessen
| | - Martin Diener
- Institute for Veterinary Physiology, University of Giessen
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