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*

ObjectiveHydrogen sulfide (HS), a gaseous signal molecule, plays a crucial role in many pathophysiologic processes in the cardiovascular system. Autophagy has been shown to participate in the occurrence of many cardiac diseases. Increasing evidences indicated that HS regulates myocardial structure and function in association with the altered autophagy and plays a "switcher" role in the autophagy of myocardial diseases. The aim of this review was to summarize these insights and provide the experimental evidence that HS targets cardiomyocyte autophagy to regulate cardiovascular function.

Data SourcesThis review was based on data in articles published in the PubMed databases up to October 30, 2017, with the following keywords: "hydrogen sulfide," "autophagy," and "cardiovascular diseases."

Study SelectionOriginal articles and critical reviews on HS and autophagy were selected for this review.

ResultsWhen autophagy plays an adaptive role in the pathogenesis of diseases, HS restores autophagy; otherwise, when autophagy plays a detrimental role, HS downregulates autophagy to exert a cardioprotective function. For example, HS has beneficial effects by regulating autophagy in myocardial ischemia/reperfusion and plays a protective role by inhibiting autophagy during the operation of cardioplegia and cardiopulmonary bypass. HS postpones cardiac aging associated with the upregulation of autophagy but improves the left ventricular function of smoking rats by lowering autophagy.

ConclusionsHS exerts cardiovascular protection by regulating autophagy. Cardiovascular autophagy would likely become a potential target of HS therapy for cardiovascular diseases.

Animals ; Autophagy ; drug effects ; Cardiovascular Diseases ; prevention & control ; Cardiovascular System ; cytology ; drug effects ; Humans ; Hydrogen Sulfide ; therapeutic use ; Myocytes, Cardiac ; cytology ; drug effects

OBJECTIVETo explore the influence of hydrogen sulfide on the intestinal biological barrier, by applying exogenous hydrogen sulfide and hydrogen sulfide synthase inhibitor for the treatment of rats with severe burn injury.

METHODSOne hundred and four SD rats were divided into sham injury (SI, n = 8), burn control (BC, n = 32), sodium hydrosulfide (SH, n = 32), and propargylglycine groups (PPG, n = 32) according to the random number table. Rats in group SI were sham injured without fluid resuscitation. Rats in the latter 3 groups were inflicted with 30% TBSA full-thickness scald (referred to as burn below) on the back and intraperitoneally injected with 40 mL/kg balanced salt solution immediately after injury. Rats in groups SH and PPG were respectively intraperitoneally injected with SH (56 µmol/kg) and PPG (45 mg/kg) within 1 hour post injury. From post injury day (PID) 2, SH (56 µmol/kg) and PPG (45 mg/kg) were respectively intraperitoneally injected once a day to rats in groups SH and PPG. Eight rats from groups BC, SH, and PPG were sacrificed on PID 2, 7, 14 and 21, and ceca samples were collected. Ceca samples were added to the appropriate culture medium after being homogenized and diluted, for the culture of Bifidobacterium, Lactobacillus, Enterococcus, Enterobacter, and Candida albicans. The content of bacteria was calculated after the bacteria number was counted. The same procedure was performed for rats in group SI. Data were processed with logarithmic function, one-way analysis of variance, analysis of variance of factorial design, and SNK-q test.

RESULTSOn each PID, the content of Bifidobacterium and Lactobacillus in the ceca of each group with burned rats was less than that of group SI (with q values from 4.12 to 20.74, P values below 0.05); while the content of Enterococcus, Enterobacter, and Candida albicans was more than that of group SI (with q values from 2.84 to 68.29, P values below 0.05). Compared with that of group BC, the content of Bifidobacterium and Lactobacillus in the ceca of rats in group SH were increased on each PID (with q values from 2.88 to 17.57, P values below 0.05). In group SH, the content of Bifidobacterium peaked as (6.54 ± 0.35) lg (CFU/g) on PID 7, the content of Lactobacillus peaked as (7.25 ± 0.71) lg (CFU/g) on PID 21. Compared with that of group BC, the content of Enterococcus, Enterobacter, and Candida albicans in the ceca of rats in group SH was reduced on each PID (with q values from 2.79 to 29.59, P values below 0.05). Compared with that of group BC, the content of Bifidobacterium and Lactobacillus in the ceca of rats in group PPG was decreased on each PID (with q values from 2.82 to 46.56, P values below 0.05); while the content of Enterococcus, Enterobacter, and Candida albicans was significantly increased on each PID (with q values from 2.93 to 41.42, P values below 0.05). In group PPG, the content of Enterococcus peaked as (9.41 ± 0.22) lg (CFU/g) on PID 21, the content of Enterobacter peaked as (9.96 ± 0.24) lg (CFU/g) on PID 14, and that of Candida albicans peaked as (3.94 ± 0.84) lg (CFU/g) on PID 14.

CONCLUSIONSExogenous hydrogen sulfide can subdue the growth of pathogenic bacteria while promote that of probiotics, thus helping maintain the integrity of intestinal biological barrier of rats with burn injury.

Animals ; Burns ; drug therapy ; pathology ; Hydrogen Sulfide ; pharmacology ; therapeutic use ; Intestines ; pathology ; Rats ; Rats, Sprague-Dawley ; Soft Tissue Injuries

BACKGROUNDDyslipidemia caused by liver injury is a significant risk factor for cardiovascular complications. Previous studies have shown that hydrogen sulfide (H2S) protects against multiple cardiovascular disease states in a similar manner as nitric oxide (NO), and NO/endothelial nitric oxide synthase (eNOS) pathway is the key route of NO production. The purpose of this study was to investigate whether H2S can ameliorate the high blood pressure and plasma lipid profile in Nw-nitro-L-argininemethyl ester (L-NAME)-induced hypertensive rats by NO/eNOS pathway.

METHODSThirty-six 4-week old Sprague-Dawley (SD) male rats were randomly assigned to 6 groups (n = 6): control group, L-NAME group, control + glibenclamide group, control + NaHS group, L-NAME + NaHS group, and L-NAME + NaHS + glibenclamide group. Measurements were made of plasma triglycerides (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), total cholesterol (CHO), glutamic-pyruvic transaminase (ALT) levels after 5 weeks. Then measurements of NO level and proteins expression of eNOS, P-eNOS, AKT, P-AKT were made in liver tissue.

RESULTSAfter 5 weeks of L-NAME treatment, the blood pressure, plasma TG ((1.22±0.12) mmol/L in L-NAME group vs. (0.68±0.09) mmol/L in control group; P < 0.05) and LDL ((0.54±0.04) mmol/L in L-NAME group vs. (0.28±0.02) mmol/L in control group; P < 0.05) concentration were significantly increased, and the plasma HDL ((0.26±0.02) mmol/L in L-NAME group vs. (0.69±0.07) mmol/L in control group; P < 0.05) concentration significantly decreased. Meanwhile the rats treated with L-NAME exhibit dysfunctional eNOS, diminished NO levels ((1.36±0.09) mmol/g protein in L-NAME group vs. (2.34±0.06) mmol/g protein in control group; P < 0.05) and pathological changes of the liver. H2S therapy can markedly decrease the blood pressure ((37.25±4.46) mmHg at the fifth week; P < 0.05), and ameliorate the plasma TG ((0.59±0.06) mmHg), LDL ((0.32±0.04) mmHg), and HDL ((0.46±0.03) mmHg) concentration in L-NAME + NaHS group (all P < 0.05). H2S therapy can also restore eNOS function and NO bioavailability and attenuate the pathological changes in the liver in L-NAME-induced hypertensive rats.

CONCLUSIONH2S protects the L-NAME-induced hypertensive rats against liver injury via NO/ eNOS pathway, therefore decreases the cardiovascular risk.

Animals ; Cardiovascular Diseases ; metabolism ; prevention & control ; Hydrogen Sulfide ; therapeutic use ; Hypertension ; chemically induced ; drug therapy ; Liver ; drug effects ; metabolism ; Male ; NG-Nitroarginine Methyl Ester ; toxicity ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase Type III ; metabolism ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; drug effects

OBJECTIVETo investigate the effect of H₂S on lower limb ischemia-reperfusion (LIR) induced lung injury and explore the underlying mechanism.

METHODSWistar rats were randomly divided into control group, IR group, IR+ Sodium Hydrosulphide (NaHS) group and IR+ DL-propargylglycine (PPG) group. IR group as lung injury model induced by LIR were given 4 h reperfusion following 4 h ischemia of bilateral hindlimbs with rubber bands. NaHS (0.78 mg/kg) as exogenous H₂S donor and PPG (60 mg/kg) which can suppress endogenous H₂S production were administrated before LIR, respectively. The lungs were removed for histologic analysis, the determination of wet-to-dry weight ratios and the measurement of mRNA and protein levels of aquaporin-1 (AQP₁), aquaporin-5 (AQP₅) as indexes of water transport abnormality, and mRNA and protein levels of Toll-like receptor 4 (TLR₄), myeloid differentiation primary-response gene 88 (MyD88) and p-NF-κB as indexes of inflammation.

RESULTSLIR induced lung injury was accompanied with upregulation of TLR₄-Myd88-NF-κB pathway and downregulation of AQP1/AQP₅. NaHS pre-treatment reduced lung injury with increasing AQP₁/AQP₅ expression and inhibition of TLR₄-Myd88-NF-κB pathway, but PPG adjusted AQP₁/AQP₅ and TLR4 pathway to the opposite side and exacerbated lung injury.

CONCLUSIONEndogenous H₂S, TLR₄-Myd88-NF-κB pathway and AQP₁/AQP₅ were involved in LIR induced lung injury. Increased H₂S would alleviate lung injury and the effect is at least partially depend on the adjustment of TLR₄-Myd88-NF-κB pathway and AQP₁/AQP₅ expression to reduce inflammatory reaction and lessen pulmonary edema.

Acute Lung Injury ; complications ; pathology ; prevention & control ; Animals ; Aquaporins ; metabolism ; Drug Evaluation, Preclinical ; Edema ; etiology ; pathology ; Hydrogen Sulfide ; pharmacology ; therapeutic use ; Inflammation ; prevention & control ; Lung ; pathology ; Male ; Myeloid Differentiation Factor 88 ; metabolism ; NF-kappa B ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Reperfusion Injury ; complications ; pathology ; prevention & control ; Toll-Like Receptor 4 ; metabolism ; Water ; metabolism

BACKGROUNDAcute lung injury (ALI) is a common syndrome associated with high morbidity and mortality in emergency medicine. Cell apoptosis plays a key role in the pathogenesis of ALI. Hydrogen sulfide (H(2)S) plays a protective role during acute lung injury. We designed this study to examine the role of H(2)S in the lung alveolar epithelial cell apoptosis in rats with ALI.

METHODSSixty-nine male Sprague Dawley rats were used. ALI was induced by intra-tail vein injection of oleic acid (OA). NaHS solution was injected intraperitonally 30 minutes before OA injection as the NaHS pretreatment group. Single sodium hydrosulfide pretreatment group and control group were designed. Index of quantitative assessment (IQA), wet/dry weight (W/D) ratio and the percentage of polymorphonuclear leukocyte (PMN) cells in the bronchoalveolar lavage fluid (BALF) were determined. H(2)S level in lung tissue was measured by a sensitive sulphur electrode. Apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining and Fas protein was measured by immunohistochemical staining.

RESULTSThe level of endogenous H(2)S in lung tissue decreased with the development of ALI induced by OA injection. Apoptosis and Fas protein in alveolar epithelial cells increased in the ALI of rats but NaHS lessened apoptosis and Fas protein expression in alveolar epithelial cells of rats with ALI.

CONCLUSIONEndogenous H(2)S protects rats from oleic acid-induced ALI, probably by inhibiting cell apoptosis.

Acute Lung Injury ; chemically induced ; drug therapy ; metabolism ; Animals ; Apoptosis ; physiology ; Epithelial Cells ; drug effects ; Hydrogen Sulfide ; metabolism ; In Situ Nick-End Labeling ; Male ; Oleic Acid ; toxicity ; Rats ; Rats, Sprague-Dawley ; Sulfides ; pharmacology ; therapeutic use

OBJECTIVETo investigate the protective effect of H2S pretreatment after cerebral schemia/reperfusion injury and its mechanisms in rats.

METHODSThe rat model of global cerebral ischemia/reperfusion injury was established by bilateral common carotid arteries occlusion combined with hemorrhagic hypotension.30 rats were randomly divided into four groups(1)sham group(n=5),in which rats received sham surgery only,with their bilateral vertebral artery and bilateral common carotid artery exposed but without ischemia treatment;(2)global cerebral ischemia/reperfusion model group(IR group,n=5),in which the global cerebral ischemia was induced by 10-min occlusion of bilateral common carotid arteries combined with hypotension;(3)H2S pretreatment group(n=15),in which H2S(12,24,48 Μmol/kg)was intraperitoneally injected before operation;(4)NaCl pretreatment group(n=5),in which the rats were intraperitoneally injected with saline 30 minutes before operation.The activities of superoxide dismutase(SOD)and the levels of malondialdeehyde(MDA)in brain were measured by spectrophotometry.Brain water content was detected.The expression of heat shock protein 70(HSP70) in the hippocampus was determined by Western blotting.

RESULTSThe SOD activities were significant increased in groups pretreated with 12Μmol/kg H2S(P=0.042),24Μmol/kg H2S(P=0.002),and 48Μmol/kg H2S(P=0.000),and the SOD activity was significantly lower in the ischemia group than in the Sham group(P=0.003).The MDA activities in the 24Μmol/kg group(P=0.026)and the 48Μmol/kg group(P=0.015)groups were significantly lower than in the IR group.The brain water content was decreased in H2S pretreatment group(24Μmol/kg and 48 Μmol/kg)compared with IR group(P=0.018,P=0.008),and it was also significantly higher in the IR group than in the sham group(P=0.009).The expression of HSP70 were decreased in H2S pretreatment group(24 Μmol/kg)compared with the IR group(P=0.000),and the expression of HSP70 were significantly higher in the IR group than in HSP70 group(P=0.000).The expression of HSP70 also significantly differed between NaCl group and HSP70 group(P=0.000).

CONCLUSIONH2S has protective effects on cerebral ischemia and reperfusion,which may be achieved by improving SOD activity,removing oxygen free radicals,inhibiting lipid peroxidation,and down-regulating the expression of HSP70 in the hippocampus.

Animals ; Brain Ischemia ; metabolism ; Free Radicals ; metabolism ; HSP70 Heat-Shock Proteins ; metabolism ; Hippocampus ; metabolism ; Hydrogen Sulfide ; administration & dosage ; therapeutic use ; Male ; Random Allocation ; Rats ; Reperfusion Injury ; metabolism ; prevention & control ; Superoxide Dismutase ; metabolism

OBJECTIVE: To determine the effect of exogenous hydrogen sulfide on experimental hepatic fibrosis in rats and its mechanism. METHODS: Wistar male rats were randomly divided into three groups: a normal control group (n=8), a model group (n=8), and a hydrogen sulfide prevention group (n=8). The rat model of hepatic fibrosis was reduced by intraperitoneal injection of carbon tetrachloride (CCl4). The prevention group, in addition to intraperitoneal injection of 40% CCl4, was intraperitoneally administered H2S once a day until 8th week. After the experiment, the liver function and liver fibrosis were assayed. Liver tissue samples were used for histopathological changes. The expression of TGF-β1 in liver tissue was detected by RT-PCR and Western blot. RESULTS: Compared with the model group, the levels of ALT, AST, HA, LN, and PC III in the sulfide group were significantly reduced (P<0.01 or P<0.05), ALB content was increased (P<0.05) in the serum, TGF-β1 expression was obviously reduced, and the degree of liver fibrosis was improved (P<0.05). CONCLUSION Exogenous hydrogen sulfide can effectively inhibit the development of hepatic fibrosis, reduce the expression of TGF-β1, and decrease the the sediment of extracellular matrix in the liver tissues.
Animals ; Carbon Tetrachloride ; Extracellular Matrix ; metabolism ; Hydrogen Sulfide ; pharmacology ; therapeutic use ; Liver ; pathology ; Liver Cirrhosis ; chemically induced ; pathology ; prevention & control ; Male ; Rats ; Rats, Wistar ; Transforming Growth Factor beta1 ; antagonists & inhibitors ; metabolism

Humans ; Hydrogen Sulfide ; poisoning ; Male ; Methylene Blue ; therapeutic use ; Poisoning ; therapy ; Young Adult

BACKGROUNDAtherosclerosis is an important cardiovascular disease, becoming a major and increasing health problem in developed countries. However, the possible underlying mechanisms were not completely clear. In 2009, our research group first discovered that hydrogen sulfide (H(2)S) as a novel gastrotransmitter played an important anti-atherosclerotic role. The study was designed to examine the regulatory effect of hydrogen sulfide (H(2)S) on endoplasmic reticulum stress (ERS) in apolipoprotein E knockout (apoE(-/-)) mice fed a Western type diet.

METHODSC57BL/6 mice and homozygous apoE(-/-) mice were fed a Western type diet. C57BL/6 mice were injected intraperitoneally with normal saline (5 ml/kg per day) as control group. The apoE(-/-) mice were treated with the same dose of normal saline as the apoE(-/-) group, injected intraperitoneally with sodium hydrosulfide (NaHS, an H(2)S donor, 56 µmol/kg per day) as the apoE(-/-) + NaHS group and injected intraperitoneally with DL-propargylglycine (PPG, a cystathionine-γ-lyase inhibitor, 50 mg/kg, per day) as the apoE(-/-) + PPG group. After 10 weeks, the mice were sacrificed and the plasma lipids were detected. Sections of aortic root from these animals were examined for atherosclerotic lesions by HE and oil red O staining. The aortic ultrastructure and microstructure were analyzed with the help of light and electronic microscope. Glucose-regulated protein 78 (GRP78), caspase-12, copper-andzinc-containing superoxide dismutase (Cu/ZnSOD) and Mn-containing superoxide dismutase (MnSOD) protein expression in aortic tissues were detected with immunohistochemistry. The level of intracellular reactive oxygen species (ROS) were measured by using a commercial assay kit.

RESULTSCompared with control mice, apoE(-/-) mice showed increased plasma levels of total cholesterol (TC), triglyceride (TG) and low density lipoprotein (LDL), decreased high density lipoprotein (HDL), increased aortic plaque size, destroyed ultra-structure of aortic tissue, and increased expression of GRP78 and caspase-12 proteins. Compared with apoE(-/-) mice, H(2)S donor-treated apoE(-/-) mice showed a decreased plasma LDL level, lessened plaque necrosis and attenuated aortic ultra-structural disorder. H(2)S donor-treatment induced GRP78 expression but suppressed caspase-12 expression in aortic lesions. However, compared with apoE(-/-) mice, PPG treated apoE(-/-) mice showed enlarged plaque size, more severe ultrastructural disorder of the aortic tissue and reduced GRP78 staining in aortic lesions. The plasma lipids and the staining of caspase-12 in apoE(-/-) + PPG rats did not significantly differ from those in the apoE-/-mice. Consistently, H(2)S induced SOD expression, accompanied by a reduced level of ROS.

CONCLUSIONH(2)S plays a regulatory role in aortic ERS and reduces atherosclerotic lesions in apoE(-/-) mice fed with a Western type diet.

Animals ; Apolipoproteins E ; genetics ; metabolism ; Atherosclerosis ; blood ; Body Weight ; drug effects ; Cholesterol ; blood ; Endoplasmic Reticulum Stress ; drug effects ; Hydrogen Sulfide ; metabolism ; Lipoproteins, HDL ; blood ; Lipoproteins, LDL ; blood ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Microscopy, Electron, Transmission ; Reactive Oxygen Species ; metabolism ; Sulfides ; pharmacology ; therapeutic use ; Triglycerides ; blood