The present study aimed to explore whether hydrogen sulfide (H₂S) improved hypoxic pulmonary hypertension (HPH) in rats by inhibiting aerobic glycolysis-pyroptosis. Male Sprague-Dawley (SD) rats were randomly divided into normal group, normal+NaHS group, hypoxia group, and hypoxia+NaHS group, with 6 rats in each group. The control group rats were placed in a normoxic (21% O₂) environment and received daily intraperitoneal injections of an equal volume of normal saline. The normal+NaHS group rats were placed in a normoxic environment and intraperitoneally injected with 14 μmol/kg NaHS daily. The hypoxia group rats were placed in a hypoxia chamber, and the oxygen controller inside the chamber maintained the oxygen concentration at 9% to 10% by controlling the N₂ flow rate. An equal volume of normal saline was injected intraperitoneally every day. The hypoxia+NaHS group rats were also placed in an hypoxia chamber and intraperitoneally injected with 14 μmol/kg NaHS daily. After the completion of the four-week modeling, the mean pulmonary artery pressure (mPAP) of each group was measured using right heart catheterization technique, and the right ventricular hypertrophy index (RVHI) was weighed and calculated. HE staining was used to observe pathological changes in lung tissue, Masson staining was used to observe fibrosis of lung tissue, and Western blot was used to detect protein expression levels of hexokinase 2 (HK2), pyruvate dehydrogenase (PDH), pyruvate kinase isozyme type M2 (PKM2), nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), GSDMD-N-terminal domain (GSDMD-N), Caspase-1, interleukin-1β (IL-1β) and IL-18 in lung tissue. ELISA was used to detect contents of IL-1β and IL-18 in lung tissue. The results showed that, compared with the normal control group, there were no significant changes in all indexes in the normal+NaHS group, while the hypoxia group exhibited significantly increased mPAP and RVHI, thickened pulmonary vascular wall, narrowed lumen, increased collagen fibers, up-regulated expression levels of aerobic glycolysis-related proteins (HK2 and PKM2), up-regulated expression levels of pyroptosis-related proteins (NLRP3, GSDMD-N, Caspase-1, IL-1β, and IL-18), and increased contents of IL-1β and IL-18. These changes of the above indexes in the hypoxia group were significantly reversed by NaHS. These results suggest that H₂S can improve rat HPH by inhibiting aerobic glycolysis-pyroptosis.
Animals ; Rats, Sprague-Dawley ; Male ; Hypertension, Pulmonary/metabolism* ; Glycolysis/drug effects* ; Hydrogen Sulfide/therapeutic use* ; Hypoxia/complications* ; Rats ; Pyroptosis/drug effects*

OBJECTIVE: To explore the protective effects and underlying mechanisms of H ₂S against lipid peroxidation-mediated carbonyl stress in the uranium-treated NRK-52E cells. METHODS: Cell viability was evaluated using CCK-8 assay. Apoptosis was measured using flow cytometry. Reagent kits were used to detect carbonyl stress markers malondialdehyde, 4-hydroxynonenal, thiobarbituric acid reactive substances, and protein carbonylation. Aldehyde-protein adduct formation and alcohol dehydrogenase, aldehyde dehydrogenase 2, aldo-keto reductase, nuclear factor E2-related factor 2 (Nrf2), and cystathionine β-synthase (CBS) expression were determined using western blotting or real-time PCR. Sulforaphane (SFP) was used to activate Nrf2. RNA interference was used to inhibit CBS expression. RESULTS: GYY4137 (an H ₂S donor) pretreatment significantly reversed the uranium-induced increase in carbonyl stress markers and aldehyde-protein adducts. GYY4137 effectively restored the uranium-decreased Nrf2 expression, nuclear translocation, and ratio of nuclear to cytoplasmic Nrf2, accompanied by a reversal of the uranium-decreased expression of CBS and aldehyde-metabolizing enzymes. The application of CBS siRNA efficiently abrogated the SFP-enhanced effects on the expression of CBS, Nrf2 activation, nuclear translocation, and ratio of nuclear to cytoplasmic Nrf2 and concomitantly reversed the SFP-enhanced effects of the uranium-induced mRNA expression of aldehyde-metabolizing enzymes. Simultaneously, CBS siRNA reversed the SFP-mediated alleviation of the uranium-induced increase in reactive aldehyde levels, apoptosis rates, and uranium-induced cell viability. CONCLUSION H ₂S induces Nrf2 activation and nuclear translocation, which modulates the expression of aldehyde-metabolizing enzymes and the CBS/H ₂S axis. Simultaneously, the Nrf2-controlled CBS/H ₂S axis may at least partially promote Nrf2 activation and nuclear translocation. These events form a cycle-regulating mode through which H ₂S attenuates the carbonyl stress-mediated NRK-52E cytotoxicity triggered by uranium.
NF-E2-Related Factor 2/genetics* ; Animals ; Hydrogen Sulfide/pharmacology* ; Rats ; Signal Transduction/drug effects* ; Lipid Peroxidation/drug effects* ; Cell Line ; Uranium/toxicity* ; Antioxidant Response Elements ; Kidney/metabolism* ; Oxidative Stress/drug effects* ; Cell Survival/drug effects* ; Apoptosis/drug effects*

Hydrogen sulphide poisoning is an acute poisoning event that occurs frequently in summer. A case of acute hydrogen sulphide poisoning in a confined space in August 2018 was investigated and clinical data were analyzed. This is a typical case of acute hydrogen sulfide gas poisoning in a confined space. The main cause of the accident is the lack of occupational protection and illegal rescue. Among the 5 patients, 3 died, 1 patient had long-term sequelae of nervous system damage such as cortical blindness, and 1 patient was cured.
Accidents ; Accidents, Occupational ; Confined Spaces ; Gas Poisoning ; Humans ; Hydrogen Sulfide ; Poisoning

Vascular calcification is a common pathological process in patients with diabetes, chronic kidney disease, and cardiovascular disease, manifested by the deposition of hydroxyapatite on the walls of blood vessels. Hydrogen sulfide is the third gas signal molecule found in mammals after nitric oxide and carbon monoxide, which has anti-inflammatory, antioxidant stress and other effects in the cardiovascular system. In recent years, it has been recognized that hydrogen sulfide has an anti-vascular calcification effect, and supplementation with hydrogen sulfide and its donors can alleviate vascular calcification. In this review, we discussed the various evidence of the protective effect of hydrogen sulfide on vascular calcification, and highlighted the hydrogen sulfide metabolism changes and the potential regulatory mechanisms of hydrogen sulfide on the pathophysiological changes in vascular calcification.
Animals ; Humans ; Hydrogen Sulfide/metabolism* ; Cardiovascular Diseases ; Carbon Monoxide ; Antioxidants ; Nitric Oxide ; Mammals/metabolism*

Objective: To investigate the effects of exogenous hydrogen sulfide (H₂S) on pulmonary vascular reactivity induced by endotoxic shock (ES) in rabbits. Methods: In this experiment, the model of endotoxic shock (ES) was induced by injection of lipopolysaccharides (LPS) to New Zealand big eared white rabbit through jugular vein (8 mg/0.8 ml/kg), the intervention was performed by H₂S donor(sodium hydrosulfide, NaHS) which was injected intraperitoneally (28 μmol/kg) 15 min in advance. New Zealand rabbits were randomly divided into 4 groups(n=8):control group, LPS group, LPS+NaHS group and NaHS group. The changes of mean arterial pressure (MAP) and mean pulmonary arterial pressure (MPAP) were detected. The tension of pulmonary artery ring (PARs) was detected byin vitro vascular ring technique. The ultrastructure of pulmonary artery wall and pulmonary artery endothelial cells were observed by light microscope and scanning electron microscope. Results: ①MAP was decreased while MPAP was increased in rabbits after LPS injection, and ES animal model was established successfully. Compared with LPS group, mPAP of rabbit in LPS+NaHS group was decreased significantly (all P＜0.05). ②Compared with normal control group, pulmonary artery of rabbits in LPS group had an increased contractile response to phenylephrine (PE) and a decreased relaxation response to acetylcholine (ACh) (both P＜0.01); Compared with LPS group, pulmonary artery of rabbits in LPS+NaHS group had a decreased contractile response to PE and an increased relaxation response to ACh (both P＜0.05). ③Under light microscope, the structure of vascular endothelial cells was continuous in the normal control group, the elastic fibers were intact in the subcutaneous layer, and the smooth muscle layer was arranged neatly. LPS can shed some of the pulmonary artery endothelial cells, break the subcutaneous elastic fibers, and disorder the smooth muscle layer structure. Compared with LPS group, the injury of pulmonary artery wall in LPS+NaHS group was ameliorated. The morphology of pulmonary artery wall was normal in NaHS group. It is showed that some endothelial cells of pulmonary artery were missing in LPS group by Scanning electron microscopy. The morphology of pulmonary artery endothelial cells in LPS+NaHS group was similar to that in the control group: slightly widened intercellular space was observed, and no cell exfoliation was observed. Conclusion: These results suggest that exogenous H₂S can protect pulmonary artery endothelial cells and regulate the reactivity changes of pulmonary artery during ES, which may be one of the mechanisms reducing PAH in ES rabbits.
Animals ; Endothelial Cells ; Hydrogen Sulfide/pharmacology* ; Hypertension, Pulmonary ; Lipopolysaccharides/adverse effects* ; Pulmonary Artery ; Rabbits ; Shock, Septic

Hydrogen sulfide is one of the most important signal transduction molecules in the body. Its anabolism and catabolism in the gastrointestinal tract(GT) are extremely high, and its role in the physiological and pathological process of the GT is fairly complicated. The study reviewed recent literature on hydrogen sulfide and GT, and proposed that hydrogen sulfide exerted dual modulating effects in the GT; specifically, it promoted the functions of the GT at low concentrations while damaged the GT at high concentrations. Hydrogen sulfide donors or metabolic modifiers exerted their therapeutic effects by restoring the metabolic homeostasis of hydrogen sulfide, and extended their efficacy to other tissues through hydrogen sulfide related gut-axis. Additionally, drugs could deviate hydrogen sulfide metabolism from the normal state due to their instability of structure, local over exposure and/or excessive pharmacological effects, thus inducing toxic and side effects or transforming therapeutic effects into toxic and side effects. This study provided references for the deep research on physiological and pathological mechanisms of hydrogen sulfide and facilitated the development of hydrogen sulfide-related drugs and discovery of their toxicity and efficacy mechanism.
Gastrointestinal Tract ; Hydrogen Sulfide/pharmacology* ; Signal Transduction

OBJECTIVE: To investigate the protective effects and underlying mechanisms of Xuebijing Injection (XBJ) on the lung endothelial barrier in hydrogen sulfide (H METHODS: Sprague-Dawley rats were exposed to H RESULTS: The morphological investigation showed that XBJ attenuated H CONCLUSIONS XBJ ameliorated H
Animals ; Claudin-5 ; Drugs, Chinese Herbal ; Endothelial Cells ; Hydrogen Sulfide ; Phosphatidylinositol 3-Kinases ; Rats ; Rats, Sprague-Dawley ; Respiratory Distress Syndrome/drug therapy*

Stomatal density is important for crop yield. In this paper, we studied the epidermal pattern factors (EPFs) related to stomatal development. Prokaryotic expression vectors were constructed to obtain EPFs. Then the relationship between EPFs and hydrogen sulfide (H2S) was established. First, AtEPF1, AtEPF2 and AtEPFL9 were cloned and constructed to pET28a vectors. Then recombinant plasmids pET28a-AtEPF1, pET28a-AtEPF2 and pET28a-AtEPFL9 were digested and sequenced, showing successful construction. Finally, they were transformed into E. coli BL21(DE3) separately and induced to express by isopropyl β-D-galactoside (IPTG). The optimized expression conditions including IPTG concentration (0.5, 0.3 and 0.05 mmol/L), temperature (28 °C, 28 °C and 16 °C) and induction time (16 h, 16 h and 20 h) were obtained. The bands of purified proteins were about 18 kDa, 19 kDa and 14.5 kDa, respectively. In order to identify their function, the purified AtEPF2 and AtEPFL9 were presented to Arabidopsis thaliana seedlings. Interestingly, the H2S production rate decreased or increased compared with the control, showing significant differences. That is, EPFs affected the production of endogenous H2S in plants. These results provide a foundation for further study of the relationship between H2S and EPFs on stomatal development, but also a possible way to increase the yield or enhance the stress resistance.
Arabidopsis ; genetics ; metabolism ; Arabidopsis Proteins ; genetics ; isolation & purification ; metabolism ; Escherichia coli ; genetics ; Genetic Vectors ; genetics ; Hydrogen Sulfide ; metabolism ; Plasmids ; genetics ; Seedlings ; metabolism

The purpose of the present study is to investigate the effect of L-cysteine on colonic motility and the underlying mechanism. Immunohistochemical staining and Western blot were used to detect the localization of the HS-generating enzymes cystathionine-β-synthase (CBS) and cystathionine-γ-lyase (CSE). Organ bath system was used to observe the muscle contractile activities. Whole-cell patch-clamp technique was applied to record ionic channels currents in colonic smooth muscle cells. The results showed that both CBS and CSE were localized in mucosa, longitudinal and circular muscle and enteric neurons. L-cysteine had a dual effect on colonic contraction, and the excitatory effect was blocked by pretreatment with CBS inhibitor aminooxyacetate acid (AOAA) and CSE inhibitor propargylglycine (PAG); L-cysteine concentration-dependently inhibited L-type calcium channel current (I) without changing the characteristic of L-type calcium channel (P < 0.01); In contrast, the exogenous HS donor NaHS increased I at concentration of 100 μmol/L, but inhibited I and modified the channel characteristics at concentration of 300 μmol/L (P < 0.05); Furthermore, L-cysteine had no effect on large conductance calcium channel current (I), but NaHS significantly inhibited I (P < 0.05). These results suggest that L-cysteine has a potential dual effect on colonic smooth muscle and the inhibitory effect might be directly mediated by L-type calcium channel while the excitatory effect might be mediated by endogenous HS.
Cystathionine beta-Synthase ; Cystathionine gamma-Lyase ; Cysteine ; pharmacology ; Hydrogen Sulfide ; Muscle, Smooth

Objective To explore the effect of hydrogen sulfide on inflammatory factors and energy metabolism of mitochondria after limbs reperfusion injury in rats. Methods Sixty rats were divided into three groups:sham operation group,control group(ischemia-reperfusion injury + saline group),and experimental group(ischemia-reperfusion injury + HS group).Wistar rat models of limb ischemia-reperfusion injury were established.Skeletal muscle samples were collected to determine the levels of necrosis decomposition products [including myoglobin(MB),lipoprotein complex(LPC)and lipid peroxide(LPO)];blood samples were collected to determine the levels of interleukin(IL)-1,IL-6 and tumor necrosis factor-α(TNF-α);mitochondria were extracted for mitochondrial transmembrane potential measurement and ATP content detection.Statistical analysis was made on the test results. Results After ischemia reperfusion injury,the levels of MB,LPO,and LPC in skeletal muscle,liver,lung and renal tissues of the control group were significantly increased(MB:P =0.003,P =0.001,P =0.001,P =0.001;LPO:P =0.001,P =0.001,P =0.001,P =0.002;LPC:P =0.000,P =0.002,P =0.002,P =0.003),and hydrogen sulfide treatment during ischemia reperfusion significantly inhibited the production of MB,LPO,and LPC(MB:P =0.021,P =0.036,P =0.005;LPO:P =0.003,P =0.008,P =0.010,P =0.015;LPC:P =0.002,P =0.026,P =0.007,P =0.006).Ischemia/reperfusion of lower extremity in rats resulted in increased levels of IL-1,IL-6,and TNF-α in the serum of rats,and the levels of IL-1,IL-6,and TNF-increased over time,with statistically significant differences in IL-1,IL-6,and TNF-α among groups at 3 h(IL-1:P =0.019,P =0.011,P =0.009,$P_{12_{h}}$=0.008,and P =0.002;IL-6:P =0.026,P =0.009,P =0.002, $P_{12_{h}}$=0.002,P =0.003;TNF-α:P =0.002,P =0.002,P =0.005,$P_{12_{h}}$=0.002,P =0.003).The levels of IL-1,IL-6,and TNF-α in serum were significantly inhibited during ischemia reperfusion(IL-1:P =0.035,P =0.039,P =0.012,$P_{12_{h}}$=0.005,P =0.006;IL-6:P =0.042,P =0.025,P =0.023,$P_{12_{h}}$=0.006,P =0.005;TNF-α:P =0.005,P =0.003,P =0.022,$P_{12_{h}}$=0.005,P =0.005),and such inhibitory effects became even more obvious over time.After limb ischemia and reperfusion in the control group,the mitochondrial transmembrane potential of skeletal muscle cells significantly decreased compared with that of the sham group(t=6.698;P=0.001).After hydrogen sulfide treatment,the mitochondrial membrane potential energy of the experimental group was significantly higher than that of the control group(t=7.507,P = 0.000).The ATP level in the mitochondria of ischemia reperfusion rats in the control group was significantly lower than that in the sham group(t=7.526,P = 0.000).The content of mitochondrial ATP in the experimental group was significantly higher than that in the control group after hydrogen sulfide treatment(t=8.604,P = 0.000). Conclusions Hydrogen sulfide can alleviate the injury of skeletal muscle and distal organs after limb ischemia-reperfusion and reduce local inflammatory reaction.In addition,it is valuable in alleviating mitochondrial transmembrane potential and energy metabolism disorders during reperfusion injury.
Animals ; Energy Metabolism ; Hydrogen Sulfide ; pharmacology ; Inflammation ; metabolism ; Interleukin-6 ; metabolism ; Mitochondrial Diseases ; pathology ; Rats ; Rats, Wistar ; Reperfusion Injury ; Tumor Necrosis Factor-alpha ; metabolism