gyy-4137 and sodium-bisulfide

Rheumatoid arthritis (RA) and osteoarthritis (OA) are widespread rheumatic diseases characterized by persistent inflammation and joint destruction. Hydrogen sulfide (H2S) is an endogenous gas with important physiologic functions in the brain, vasculature and other organs. Recent studies have found H2S to be a mediator in inflammatory joint diseases.. This review summarizes the recent literature in this area highlighting relevant developments.. Several authors have found that H2S exhibited anti-inflammatory, anti-catabolic and/or anti-oxidant effects in rodent models of acute arthritis and in in vitro models using human synoviocytes and articular chondrocytes from RA and OA tissues. The earliest studies used fast-dissolving salts, such as NaSH, but GYY4137, which produces H2S more physiologically, shortly appeared. More recently still, new H2S-forming compounds that target mitochondria have been synthesized. These compounds open exciting opportunities for investigating the role of H2S in cell bioenergetics, typically altered in arthritides. Positive results have also been obtained when H2S is administered as a sulphurous water bath, an option meriting further study. These findings suggest that exogenous supplementation of H2S may provide a viable therapeutic option for these diseases, particularly in OA.

Topics: Animals; Arthritis, Rheumatoid; Cells, Cultured; Clinical Trials as Topic; Disease Models, Animal; Humans; Hydrogen Sulfide; Morpholines; Organothiophosphorus Compounds; Osteoarthritis; Sulfides; Treatment Outcome

Impaired polymorphonuclear leukocyte (PMNL) functions contribute to increased infections and cardiovascular diseases in chronic kidney disease (CKD). Uremic toxins reduce hydrogen sulfide (H

Topics: Cysteine; Escherichia coli; Hydrogen Sulfide; Neutrophils; Phosphatidylinositol 3-Kinases

Topics: Apoptosis; Autophagy; beta Catenin; Cell Line, Tumor; Cell Proliferation; Esophageal Neoplasms; Esophageal Squamous Cell Carcinoma; Glycogen Synthase Kinase 3 beta; Humans; Hyaluronic Acid; Hydrogen Sulfide; Morpholines; Organothiophosphorus Compounds; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Sulfides; Thiones; TOR Serine-Threonine Kinases

Hydrogen sulfide (H

Topics: AMP-Activated Protein Kinases; Animals; Autophagy; Cell Survival; Dopaminergic Neurons; Dose-Response Relationship, Drug; HEK293 Cells; Humans; Hydrogen Sulfide; Morpholines; Organothiophosphorus Compounds; PC12 Cells; Phosphorylation; Rats; Sulfides

Hydrogen sulfide donors reduce inflammatory signaling in vitro and in vivo. The biological effect mediated by H. We investigated the effects of GYY4137 and sodium hydrosulfide on the release of proinflammatory molecules such as ROS, NO and TNF-α from LPS-treated human SH-SY5Y neuroblastoma and the THP-1 promonocytic cell lines. Transcriptomic and RT-qPCR studies using THP-1 cells were performed to monitor the effects of the GYY4137 on multiple signaling pathways, including various immune-related and proinflammatory genes after combined action of LPS and GYY4137.. The GYY4137 and sodium hydrosulfide differed in the ability to reduce the production of the LPS-evoked proinflammatory mediators. The pre-treatment with GYY4137 resulted in a drastic down-regulation of many TNF-α effectors that are induced by LPS treatment in THP-1 cells. Furthermore, GYY4137 pretreatment of LPS-exposed cells ameliorates the LPS-mediated induction of multiple pro-inflammatory genes and decreases expression of immunoproteasome genes. Besides, in these experiments we detected the up-regulation of several important pathways that are inhibited by LPS.. Based on the obtained results we believe that our transcriptomic analysis significantly contributes to the understanding of the molecular mechanisms of anti-inflammatory and cytoprotective activity of hydrogen sulfide donors, and highlights their potential against LPS challenges and other forms of inflammation.

Topics: Anti-Inflammatory Agents; Cell Line; Cytokines; Humans; Hydrogen Sulfide; Inflammation; Lipopolysaccharides; Morpholines; Nitric Oxide; Organothiophosphorus Compounds; Reactive Oxygen Species; Signal Transduction; Sulfides; Transcriptome

Topics: Animals; Atrial Natriuretic Factor; Heart Atria; Hydrogen Sulfide; In Vitro Techniques; KATP Channels; Male; Morpholines; Nitric Oxide Synthase; Organothiophosphorus Compounds; Radioimmunoassay; Rats; Rats, Sprague-Dawley; Soluble Guanylyl Cyclase; Sulfides; Thiosulfates

Hydrogen sulfide (H

Topics: Animals; Antihypertensive Agents; Aorta, Thoracic; Female; Fetal Growth Retardation; Fetus; Hydrogen Sulfide; Hypertension; Litter Size; Malondialdehyde; Morpholines; Organothiophosphorus Compounds; Placenta; Pregnancy; Rats, Wistar; Sulfides

The study was designed to examine if the vasorelaxant effect of hydrogen sulfide was mediated by sulfhydration-associated phosphodiesterase (PDE) 5A dimerization. The thoracic aorta of rat was separated and the vasorelaxant effects were examined with in vitro vascular perfusion experiments. The dimerization and sulfhydration of PDE 5A and soluble guanylatecyclase (sGC) were measured. PDE 5A and protein kinase G (PKG) activities were tested. Intracellular cGMP content was detected by enzyme-linked immunosorbent assay (ELISA). The results showed that NaHS relaxed isolated rat vessel rings at an EC50 of (1.79 ± 0.31)×10-5mol/L, associated with significantly increased PKG activity and cGMP content in vascular tissues. Sulfhydration of sGC β1 was increased, while the levels of sGC αβ1 dimers were apparently decreased after incubation with NaHS in vascular tissues. Moreover, PDE 5A homodimers were markedly decreased, and accordingly the PDE 5A activity demonstrated by the content of 5'-GMP was significantly decreased after incubation with NaHS or GYY4137. Mechanistically, both NaHS and GYY4137 significantly enhanced the PDE 5A sulfhydration in vascular tissues. DTT partially abolished the effects of NaHS on PDE 5A activity, cGMP content and vasorelaxation. Therefore, the present study for the first time suggested that H2S exerted vasorelaxant effect probably via sulfhydration-associated PDE 5A dimerization.

Topics: Animals; Aorta; Cyclic GMP; Cyclic GMP-Dependent Protein Kinases; Cyclic Nucleotide Phosphodiesterases, Type 5; Enzyme Activation; Guanylate Cyclase; Hydrogen Sulfide; Male; Morpholines; Myocytes, Smooth Muscle; Organothiophosphorus Compounds; Protein Multimerization; Rats; Signal Transduction; Sulfides; Vasodilator Agents

Recently, the gastrointestinal microbiome, and its metabolites, has emerged as a potential regulator of host metabolism. However, to date little is known on the precise mechanisms of how this regulation occurs. Hydrogen sulfide (H2S) is abundantly produced in the colon by sulfate-reducing bacteria (SRB). H2S is a bioactive gas that plays regulatory roles in many systems, including metabolic hormone regulation. This gas metabolite is produced in close proximity to the glucagonlike peptide-1 (GLP-1)-secreting cells in the gut epithelium. GLP-1 is a peptide hormone that plays pivotal roles in both glucose homeostasis and appetite regulation. We hypothesized that H2S can directly regulate GLP-1 secretion. We demonstrated that H2S donors (NaHS and GYY4137) directly stimulate GLP-1 secretion in murine L-cells (GLUTag) and that this occurs through p38 mitogen-activated protein kinase without affecting cell viability. We then increased SRB in mice by supplementing the diet with a prebiotic chondroitin sulfate for 4 weeks. Mice treated with chondroitin sulfate had elevated Desulfovibrio piger levels in the feces and increased colonic and fecal H2S concentration. These animals also had enhanced GLP-1 and insulin secretion, improved oral glucose tolerance, and reduced food consumption. These results indicate that H2S plays a stimulatory role in GLP-1 secretion and that sulfate prebiotics can enhance GLP-1 release and its downstream metabolic actions.

Topics: Animals; Blotting, Western; Chondroitin Sulfates; Colon; Desulfovibrio; DNA, Bacterial; Eating; Feces; Gastrointestinal Microbiome; Glucagon-Like Peptide 1; Glucose Tolerance Test; Hydrogen Sulfide; Insulin; Insulin Secretion; Intestinal Mucosa; Male; Mice; Morpholines; Organothiophosphorus Compounds; Prebiotics; Real-Time Polymerase Chain Reaction; Sulfides

Autophagy plays an important role in cellular homeostasis through the disposal and recycling of cellular components. Hydrogen sulphide (H2S) is the third endogenous gas that has been shown to confer cardiac protective effects. Given the regulation of autophagy in cardioprotection, this study aimed to investigate the protective effects of H2S via autophagy during high glucose treatment.. This study investigated the content of H2S in the plasma as well as myocardial, ultrastructural changes in mitochondria and autophagosomes. This study also investigated the apoptotic rate using Hoechst/PI as well as expression of autophagy-associated proteins and mitochondrial apoptotic proteins in H9C2 cells treated with or without GYY4137. Mitochondria of cardiac tissues were isolated and RCR and ADP/O were also detected. AMPK knockdown was performed with siRNA transfection.. In a STZ-induced diabetic model, NaHS treatment not only increased the expression of p-AMPK in diabetic group but further activated cell autophagy. Following 48h high glucose, autophagosomes and cell viability were reduced. The present results showed that autophagy could be induced by H2S, which was verified by autophagic ultrastructural observation and LC3-I/LC3-II conversion. In addition, the mitochondrial membrane potential (MMP) was significantly decreased. The expressions levels of autophagic-related proteins were significantly elevated. Moreover, H2S activated the AMPK/rapamycin (mTOR) signalling pathway.. Our findings demonstrated that H2S decreases oxidative stress and protects against mitochondria injury, activates autophagy, and eventually leads to cardiac protection via the AMPK/mTOR pathway.

Topics: AMP-Activated Protein Kinases; Animals; Autophagy; Blood Glucose; Cardiotonic Agents; Cell Line; Cell Survival; Diabetes Mellitus, Experimental; Diabetic Cardiomyopathies; Disease Models, Animal; Glucose; Male; Membrane Potential, Mitochondrial; Mitochondria; Morpholines; Organothiophosphorus Compounds; Oxidative Stress; Rats; Rats, Wistar; Signal Transduction; Streptozocin; Sulfides; TOR Serine-Threonine Kinases; Ventricular Function

The effect of hydrogen sulfide (H2S) on differentiation of 3T3L1-derived adipocytes was examined. Endogenous H2S was increased after 3T3L1 differentiation. The expression of the H2S-synthesising enzymes, cystathionine γ-lyase (CSE), cystathionine β-synthase (CBS) and 3-mercaptopyruvate sulfurtransferase (3-MST), was increased in a time-dependent manner during 3T3L1 differentiation. Expression of genes associated with adipogenesis related genes including fatty acid binding protein 4 (FABP4/aP2), a key regulator of this process, was increased by GYY4137 (a slow-releasing H2S donor compound) and sodium hydrosulfide (NaHS, a classical H2S donor) but not by ZYJ1122 or time-expired NaHS. Furthermore expression of these genes were reduced by aminooxyacetic acid (AOAA, CBS inhibitor), DL-propargylglycine (PAG, CSE inhibitor) as well as by CSE small interference RNA (siCSE) and siCBS. The size and number of lipid droplets in mature adipocytes was significantly increased by both GYY4137 and NaHS, which also impaired the ability of CL316,243 (β3-agonist) to promote lipolysis in these cells. In contrast, AOAA and PAG had the opposite effect. Taken together, we show that the H2S-synthesising enzymes CBS, CSE and 3-MST are endogenously expressed during adipogenesis and that both endogenous and exogenous H2S modulate adipogenesis and adipocyte maturation.

Topics: 3T3-L1 Cells; Adipocytes; Adipogenesis; Animals; Cell Differentiation; Cystathionine beta-Synthase; Cystathionine gamma-Lyase; Fatty Acid-Binding Proteins; Gene Expression; Glycerol; Hydrogen Sulfide; Lipid Metabolism; Lipolysis; Mice; Morpholines; Organothiophosphorus Compounds; RNA, Messenger; Sulfides; Sulfurtransferases

Oxidative stress inducing hyperglycemia and high glucose play an important role in the development of cardiac fibrosis associated with diabetic cardiomyopathy. The endogenous gasotransmitter hydrogen sulfide (H2S) can act in a cytoprotective manner. However, whether H2S could inhibit the fibrotic process is unclear. The purpose of our study was to examine the role of H2S in the development and underlying mechanisms behind diabetic cardiomyopathy.. Diabetic cardiomyopathy was induced in rats by injection of streptozotocin (STZ). Cardiac fibrosis and proliferation of rat neonatal cardiac fibroblasts were induced by hyperglycemia and high glucose. We tested the effects of GYY4137 (a slow-releasing H2S donor), NaHS (an exogenous H2S donor) and NADPH oxidase 4 (NOX4) siRNA on reactive oxygen species (ROS) production, MMP-2,9, cystathionine-γ-lyase (CSE), NOX4, and extracellular signal-regulated kinase 1/2 (ERK1/2) to reveal the effects of H2S on the cardiac fibrosis of diabetic cardiomyopathy.. In vivo, NaHS treatment inhibited hyperglycemia-induced expression of type I and III collagen, MMP-2 and MMP-9 in diabetic hearts. Rat neonatal cardiac fibroblast migration and cell survival were inhibited by administration of GYY4137. NOX4 expression was increased by hyperglycemia and high glucose, but was reduced in cardiac fibroblasts treated by NaHS and GYY4137. ROS production, ERK1/2 phosphorylation and MMP-2 and 9 expression were decreased in rat neonatal cardiac fibroblasts treated with GYY4137 and NOX4 siRNA.. The present study shows that enhanced NOX4 expression results in cardiac fibrosis through ROS-ERK1/2-MAPkinase-dependent mechanisms in diabetic cardiomyopathy. NOX4 could be an important target for H2S to regulate redox homeostasis in cardiac fibrosis of diabetic cardiomyopathy.

Topics: Animals; Animals, Newborn; Diabetes Mellitus, Experimental; Fibroblasts; Gene Expression Regulation; Glucose; Hydrogen Sulfide; Hyperglycemia; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Morpholines; NADPH Oxidase 4; NADPH Oxidases; Organothiophosphorus Compounds; Primary Cell Culture; Rats; Rats, Wistar; Reactive Oxygen Species; RNA, Small Interfering; Signal Transduction; Streptozocin; Sulfides

Arrested alveolarization is the pathological hallmark of bronchopulmonary dysplasia (BPD), a complication of premature birth. Here, the impact of systemic application of hydrogen sulfide (H2S) on postnatal alveolarization was assessed in a mouse BPD model. Exposure of newborn mice to 85% O2 for 10 days reduced the total lung alveoli number by 56% and increased alveolar septal wall thickness by 29%, as assessed by state-of-the-art stereological analysis. Systemic application of H2S via the slow-release H2S donor GYY4137 for 10 days resulted in pronounced improvement in lung alveolarization in pups breathing 85% O2, compared with vehicle-treated littermates. Although without impact on lung oxidative status, systemic H2S blunted leukocyte infiltration into alveolar air spaces provoked by hyperoxia, and restored normal lung interleukin 10 levels that were otherwise depressed by 85% O2. Treatment of primary mouse alveolar type II (ATII) cells with the rapid-release H2S donor NaHS had no impact on cell viability; however, NaHS promoted ATII cell migration. Although exposure of ATII cells to 85% O2 caused dramatic changes in mRNA expression, exposure to either GYY4137 or NaHS had no impact on ATII cell mRNA expression, as assessed by microarray, suggesting that the effects observed were independent of changes in gene expression. The impact of NaHS on ATII cell migration was attenuated by glibenclamide, implicating ion channels, and was accompanied by activation of Akt, hinting at two possible mechanisms of H2S action. These data support further investigation of H2S as a candidate interventional strategy to limit the arrested alveolarization associated with BPD.

Topics: Animals; Animals, Newborn; Bronchopulmonary Dysplasia; Cytokines; Disease Models, Animal; Hydrogen Sulfide; Hyperoxia; Lung; Mice; Morpholines; Organothiophosphorus Compounds; Oxygen; Proto-Oncogene Proteins c-akt; Pulmonary Alveoli; Sulfides; Wound Healing

Many disparate studies have reported the ambiguous role of hydrogen sulfide (H2 S) in cell survival. The present study investigated the effect of H2 S on the viability of cancer and non-cancer cells.. Cancer and non-cancer cells were exposed to H2 S [using sodium hydrosulfide (NaHS) and GYY4137] and cell viability was examined by crystal violet assay. We then examined cancer cellular glycolysis by in vitro enzymatic assays and pH regulator activity. Lastly, intracellular pH (pHi ) was determined by ratiometric pHi measurement using BCECF staining.. Continuous, but not a single, exposure to H2 S decreased cell survival more effectively in cancer cells, as compared to non-cancer cells. Slow H2 S-releasing donor, GYY4137, significantly increased glycolysis, leading to overproduction of lactate. H2 S also decreased anion exchanger and sodium/proton exchanger activity. The combination of increased metabolic acid production and defective pH regulation resulted in an uncontrolled intracellular acidification, leading to cancer cell death. In contrast, no significant intracellular acidification or cell death was observed in non-cancer cells.. Low and continuous exposure to H2 S targets metabolic processes and pH homeostasis in cancer cells, potentially serving as a novel and selective anti-cancer strategy.

Topics: Antineoplastic Agents; Cell Line; Cell Line, Tumor; Cell Survival; Glucose; Glycolysis; Humans; Hydrogen Sulfide; Hydrogen-Ion Concentration; Morpholines; Neoplasms; Organothiophosphorus Compounds; Sulfides

Hydrogen sulfide (H2S), the third gasotransmitter together with NO and CO, is emerging as a regulator of inflammation. To test if it might offer therapeutic value in the treatment of osteoarthritis (OA) we evaluated the effects of two exogenous sources of H2S, NaSH and GYY4137, on inflammation and catabolic markers that characterize OA.. Human chondrocytes (CHs) were isolated from OA tissue. Cells were stimulated with a pro-inflammatory cytokine (interleukin-1β, IL1β, 5 ng/ml) and the ability of the two H2S sources to ameliorate its effects on the cells was tested. Nitric oxide (NO) production was quantified through the Griess reaction. Protein levels of inducible NO synthase (NOS2) and matrix metalloproteinase 13 (MMP13) were visualized through immunocytochemistry (ICC). Relative mRNA expression was quantified with qRT-PCR. Prostaglandin-2 (PGE-2), interleukin 6 (IL6) and MMP13 levels were measured with specific EIAs. NFκB nuclear translocation was visualized with immunofluorescence.. Both H2S sources led to significant reductions in NO, PGE-2, IL6 and MMP13 released by the cells and at the protein level. This was achieved by downregulation of relevant genes involved in the synthesis routes of these molecules, namely NOS2, cyclooxigenase-2 (COX2), prostaglandin E synthase (PTGES), IL6 and MMP13. NFκB nuclear translocation was also reduced.. NaSH and GYY4137 show anti-inflammatory and anti-catabolic properties when added to IL1β activated osteoarthritic CHs. Supplementation with exogenous H2S sources can regulate the expression of relevant genes in OA pathogenesis and progression, counteracting IL1β pro-inflammatory signals that lead to cartilage destruction in part by reducing NFκB activation.

Topics: Aged; Aged, 80 and over; Biomarkers; Cartilage, Articular; Cells, Cultured; Chondrocytes; Dinoprostone; Female; Humans; Hydrogen Sulfide; Inflammation; Interleukin-1beta; Interleukin-6; Male; Matrix Metalloproteinase 13; Metabolism; Morpholines; NF-kappa B; Nitric Oxide; Nitric Oxide Synthase; Organothiophosphorus Compounds; Osteoarthritis; Sulfides

Cerebral malaria (CM) is a potentially fatal cerebrovascular disease of complex pathogenesis caused by Plasmodium falciparum. Hydrogen sulfide (HS) is a physiological gas, similar to nitric oxide and carbon monoxide, involved in cellular metabolism, vascular tension, inflammation, and cell death. HS treatment has shown promising results as a therapy for cardio- and neuro- pathology. This study investigates the effects of fast (NaHS) and slow (GYY4137) HS-releasing drugs on the growth and metabolism of P. falciparum and the development of P. berghei ANKA CM. Moreover, we investigate the role of free plasma thiols and cell surface thiols in the pathogenesis of CM.. P. falciparum was cultured in vitro with varying doses of HS releasing drugs compared with artesunate. Growth and metabolism were quantified. C57Bl/6 mice were infected with P. berghei ANKA and were treated with varying doses and regimes of HS-releasing drugs. Free plasma thiols and cell surface thiols were quantified in CM mice and age-matched healthy controls.. HS-releasing drugs significantly and dose-dependently inhibited P. falciparum growth and metabolism. Treatment of CM did not affect P. berghei growth, or development of CM. Interestingly, CM was associated with lower free plasma thiols, reduced leukocyte+erythrocyte cell surface thiols (infection day 3), and markedly (5-fold) increased platelet cell surface thiols (infection day 7).. HS inhibits P. falciparum growth and metabolism in vitro. Reduction in free plasma thiols, cell surface thiols and a marked increase in platelet cell surface thiols are associated with development of CM. HS drugs were not effective in vivo against murine CM.

Topics: Animals; Antimalarials; Artemisinins; Artesunate; Blood Platelets; Dose-Response Relationship, Drug; Erythrocytes; Humans; Hydrogen Sulfide; Malaria, Cerebral; Mice; Mice, Inbred C57BL; Morpholines; Organothiophosphorus Compounds; Plasmodium berghei; Plasmodium falciparum; Species Specificity; Sulfhydryl Compounds; Sulfides

Hydrogen sulfide (H2S) is suggested to act as a gaseous signaling molecule in a variety of physiological processes. Its molecular mechanism of action was proposed to involve protein S-sulfhydration, that is, conversion of cysteinyl thiolates (Cys-S(-)) to persulfides (Cys-S-S(-)). A central and unresolved question is how H2S-that is, a molecule with sulfur in its lowest possible oxidation state (-2)-can lead to oxidative thiol modifications.. Using the lipid phosphatase PTEN as a model protein, we find that the "H2S donor" sodium hydrosulfide (NaHS) leads to very rapid reversible oxidation of the enzyme in vitro. We identify polysulfides formed in NaHS solutions as the oxidizing species, and present evidence that sulfane sulfur is added to the active site cysteine. Polysulfide-mediated oxidation of PTEN was induced by all "H2S donors" tested, including sodium sulfide (Na2S), gaseous H2S, and morpholin-4-ium 4-methoxyphenyl(morpholino) phosphinodithioate (GYY4137). Moreover, we show that polysulfides formed in H2S solutions readily modify PTEN inside intact cells.. Our results shed light on the previously unresolved question of how H2S leads to protein thiol oxidation, and suggest that polysulfides formed in solutions of H2S mediate this process.. This study suggests that the effects that have been attributed to H2S in previous reports may in fact have been mediated by polysulfides. It also supports the notion that sulfane sulfur rather than sulfide is the actual in vivo agent of H2S signaling.

Topics: Catalytic Domain; Cell Line; Cysteine; Enzyme Activation; Humans; Hydrogen Sulfide; Kinetics; Morpholines; Organothiophosphorus Compounds; Oxidation-Reduction; Proteins; PTEN Phosphohydrolase; Solutions; Sulfhydryl Compounds; Sulfides

Hydrogen sulfide (H(2)S) is a novel signaling molecule with both pro- or anti-inflammatory effect. The present study aimed to: (i) characterize the in vitro effects of H(2)S on human keratinocyte's proliferation and death; (ii) investigate the ability of H(2)S to modulate VEGF and NO production; (iii) examine the intracellular signaling pathways involved in VEGF and NO modulatory effect. We found that exogenous application of H(2)S (NaHS and GYY4137 as H(2)S donors) significantly enhances NO through increase of iNOS, in a manner Akt-dependent. The increment in NO down-regulates ERK1/2 activation thereby resulting in the decrease of VEGF release. We suggest that H(2)S-releasing agents may be promising therapeutics for chronic inflammatory disorders of the skin, i.e. psoriasis, in which NO increases as well as anti-VEGF treatments have been suggested to be novel effective approaches.

Topics: Cell Line; Cell Proliferation; Cell Survival; Humans; Hydrogen Sulfide; Keratinocytes; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Morpholines; Nitric Oxide; Nitric Oxide Synthase Type II; Organothiophosphorus Compounds; Proto-Oncogene Proteins c-akt; Sulfides; Vascular Endothelial Growth Factor A

Better tocolytics are required to help prevent preterm labour. The gaseotransmitter Hydrogen sulphide (H(2)S) has been shown to reduce myometrial contractility and thus is of potential interest. However previous studies used NaHS, which is toxic and releases H(2)S as a non-physiological bolus and thus alternative H(2)S donors are sought. GYY4137 has been developed to slowly release H(2)S and hence better reflect endogenous physiological release. We have examined its effects on spontaneous and oxytocin-stimulated contractility and compared them to NaHS, in human and rat myometrium, throughout gestation. The effects on contractility in response to GYY4137 (1 nM-1 mM) and NaHS (1 mM) were examined on myometrial strips from, biopsies of women undergoing elective caesarean section or hysterectomy, and from non-pregnant, 14, 18, 22 day (term) gestation or labouring rats. In pregnant rat and human myometrium dose-dependent and significant decreases in spontaneous contractions were seen with increasing concentrations of GYY4137, which also reduced underlying Ca transients. GYY4137 and NaHS significantly reduced oxytocin-stimulated and high-K depolarised contractions as well as spontaneous activity. Their inhibitory effects increased as gestation advanced, but were abruptly reversed in labour. Glibenclamide, an inhibitor of ATP-sensitive potassium (K(ATP)) channels, abolished the inhibitory effect of GYY4137. These data suggest (i) H(2)S contributes to uterine quiescence from mid-gestation until labor, (ii) that H(2)S affects L-type calcium channels and K(ATP) channels reducing Ca entry and thereby myometrial contractions, (iii) add to the evidence that H(2)S plays a physiological role in relaxing myometrium, and thus (iv) H(2)S is an attractive target for therapeutic manipulation of human myometrial contractility.

Topics: Adult; Animals; Calcium Channels, L-Type; Dose-Response Relationship, Drug; Female; Glyburide; Humans; Hydrogen Sulfide; KATP Channels; Labor, Obstetric; Middle Aged; Morpholines; Myometrium; Obstetric Labor, Premature; Organothiophosphorus Compounds; Oxytocics; Oxytocin; Pregnancy; Rats; Sulfides; Tocolytic Agents; Uterine Contraction

Hydrogen sulfide (H(2)S) is synthesized intracellularly by the enzymes cystathionine-γ-lyase and cystathionine-β-synthase (CBS), and is proposed to be a gasotransmitter with effects in modulating inflammation and cellular proliferation. We determined a role of H(2)S in airway smooth muscle (ASM) function. ASM were removed from resection or transplant donor lungs and were placed in culture. Proliferation of ASM was induced by FCS and the proinflammatory cytokine, IL-1β. Proliferation of ASM and IL-8 release were measured by bromodeoxyuridine incorporation and ELISA, respectively. Exposure of ASM to H(2)S "donors" inhibited this proliferation and IL-8 release. Methemoglobin, a scavenger of endogenous H(2)S, increased DNA synthesis induced by FCS and IL-1β. In addition, methemoglobin increased IL-8 release induced by FCS, but not by IL-1β, indicating a role for endogenous H(2)S in these systems. Inhibition of CBS, but not cystathionine-γ-lyase, reversed the inhibitory effect of H(2)S on proliferation and IL-8 release, indicating that this is dependent on CBS. CBS mRNA and protein expression were inhibited by H(2)S donors, and were increased by methemoglobin, indicating that CBS is the main enzyme responsible for endogenous H(2)S production. Finally, we found that exogenous H(2)S inhibited the phosphorylation of extracellular signal-regulated kinase-1/2 and p38, which could represent a mechanism by which H(2)S inhibited cellular proliferation and IL-8 release. In summary, H(2)S production provides a novel mechanism for regulation of ASM proliferation and IL-8 release. Therefore, regulation of H(2)S may represent a novel approach to controlling ASM proliferation and cytokine release that is found in patients with asthma.

Topics: Bronchi; Cell Proliferation; Cells, Cultured; Cystathionine beta-Synthase; Cystathionine gamma-Lyase; Dose-Response Relationship, Drug; Enzyme-Linked Immunosorbent Assay; Humans; Hydrogen Sulfide; Interleukin-1beta; Interleukin-8; Methemoglobin; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Morpholines; Myocytes, Smooth Muscle; Organothiophosphorus Compounds; p38 Mitogen-Activated Protein Kinases; Protein Kinase Inhibitors; Serum; Sulfides

Hydrogen sulfide (H(2)S) has recently been reported to be a signaling molecule in plants. It has been well established that is has such roles in animals and it has been suggested that it is included into the group of gasotransmitters. We have recently shown that hydrogen sulfide causes stomatal opening in the model plant Arabidopsis thaliana. H(2)S can be supplied to the plant tissues from donors such as sodium hydrosulfide (NaSH) or more recently from slow release H(2)S donor molecules such as GYY4137. Both give similar effects, that is, they cause stomatal opening. Furthermore both H(2)S donors reduced the accumulation of nitric oxide (NO) induced by abscisic acid (ABA) treatment of leaf tissues. Here similar work has been repeated in a crop plant, Capsium anuum, and similar data has been obtained, suggesting that such effects of hydrogen sulfide on plants is not confined to model species.

Topics: Capsicum; Hydrogen Sulfide; Morpholines; Nitric Oxide; Organothiophosphorus Compounds; Plant Stomata; Sulfides

The role of hydrogen sulfide (H(2)S) in inflammation is controversial, with both pro- and antiinflammatory effects documented. Many studies have used simple sulfide salts as the source of H(2)S, which give a rapid bolus of H(2)S in aqueous solutions and thus do not accurately reflect the enzymatic generation of H(2)S. We therefore compared the effects of sodium hydrosulfide and a novel slow-releasing H(2)S donor (GYY4137) on the release of pro- and antiinflammatory mediators in lipopolysaccharide (LPS)-treated murine RAW264.7 macrophages. For the first time, we show that GYY4137 significantly and concentration-dependently inhibits LPS-induced release of proinflammatory mediators such as IL-1beta, IL-6, TNF-alpha, nitric oxide (*NO), and PGE(2) but increased the synthesis of the antiinflammatory chemokine IL-10 through NF-kappaB/ATF-2/HSP-27-dependent pathways. In contrast, NaHS elicited a biphasic effect on proinflammatory mediators and, at high concentrations, increased the synthesis of IL-1beta, IL-6, NO, PGE(2) and TNF-alpha. This study clearly shows that the effects of H(2)S on the inflammatory process are complex and dependent not only on H(2)S concentration but also on the rate of H(2)S generation. This study may also explain some of the apparent discrepancies in the literature regarding the pro- versus antiinflammatory role of H(2)S.

Topics: Activating Transcription Factor 2; Air Pollutants; Animals; Cell Line; HSP27 Heat-Shock Proteins; Hydrogen Sulfide; Inflammation Mediators; Lipopolysaccharides; Macrophages; Mice; Morpholines; NF-kappa B; Organothiophosphorus Compounds; Sulfides