Intraperitoneal Injection Of NaHS Research Articles

Exogenous H2S Protects against Septic Cardiomyopathy by Inhibiting Autophagy through the AMPK/mTOR Pathway

Background Given the cardioprotective role of autophagy, this study aimed to investigate the protective effect of exogenous H2S (NaHS) on infectious cardiomyopathy through the inhibition of the AMPK/mTOR pathway. Methods In this study, sepsis models were established by cecal ligation and puncture (CLP) induction in vivo and intraperitoneal injection of NaHS was performed. Autophagy- and apoptosis-related proteins were observed by western blot, isolated myocardial tissue morphology was observed by hematoxylin-eosin (H&E) staining, and myocardial apoptosis was evaluated by the tunnel method. The ultrastructure of autophagy was observed by using an electron transmission electron microscope. Results In an SD rat model of cecum ligation puncture-induced sepsis, the level of autophagy-related proteins was significantly increased, and hematoxylin and eosin staining showed irregular myocardial bands and swollen cardiomyocytes. Following NaHS treatment, the level of autophagy-related proteins decreased, and electron transmission microscopy revealed decreased autophagosomes. Echocardiography suggested an increase in ejection fraction and significant relief of myocardial inhibition. Conclusions Our results suggest that NaHS treatment can attenuate the cellular damage caused by excessive autophagy through the AMPK/mTOR pathway.

Autophagy Plays a Protective Role in Sodium Hydrosulfide-Induced Acute Lung Injury by Attenuating Oxidative Stress and Inflammation in Rats.

Sodium hydrosulfide (NaHS), as an exogenous hydrogen sulfide (H2S) donor, has been used in various pathological models. NaHS is usually considered to be primarily protective, however, the toxic effect of NaHS has not been well elucidated. The aim of this study was to investigate whether NaHS (1 mg/kg) can induce acute lung injury (ALI is a disease process characterized by diffuse inflammation of the lung parenchyma) and define the mechanism by which NaHS-induced ALI involves autophagy, oxidative stress, and inflammatory response. Wistar rats were randomly divided into three groups (control group, NaHS group, and 3-MA + NaHS group), and samples from each group were collected from 2, 6, 12, and 24 h. We found that intraperitoneal injection of NaHS (1 mg/kg) increased the pulmonary levels of H2S and oxidative stress-related indicators (reactive oxygen species, myeloperoxidase, and malondialdehyde) in a time-dependent manner. Intraperitoneal injection of NaHS (1 mg/kg) induced histopathological changes of ALI and inhibition of autophagy exacerbated the lung injury. This study demonstrates that administration of NaHS (1 mg/kg) induces ALI in rats and autophagy in response to ROS is protective in NaHS-induced ALI by attenuating oxidative stress and inflammation.

Sodium Hydrosulfide Post-conditioning Protects Hippocampal CA1 Neurons from Neuronal Cell Injury in the Rat Model of Transient Global Cerebral Ischemia Through Activation of Extracellular-regulated Kinases Signaling.

The effect of hydrogen sulfide (H2S) on global cerebral ischemia remains partially understood. This study aimed to investigate the neuroprotective effect of sodium hydrosulfide (NaHS, a donor of H2S) post-conditioning and its underlying mechanism in a transient global cerebral ischemia (tGCI) model. The tGCI rat model was established by the four-vessel occlusion method. Wistar rats were randomly assigned into 6 groups: sham, tGCI, tGCI +NaHS, tGCI+vehicle, tGCI+U0126 and tGCI+U0126+NaHS groups. Neurons survival was assessed by Nissl staining and NeuN immunostaining. Levels of extracellular extracellular-regulated kinases (ERK)1/2 and p-ERK1/2 were determined by western blot and immunohistochemistry (IHC). Intraperitoneal injection of NaHS (24 µmol/kg) at 24 h post-tGCI attenuated tGCI-induced decrease of the survival and NeuN-positive neurons in the hippocampal CA1 subregion. Compared to the sham group, tGCI significantly up-regulated p-ERK1/2 protein at 26 and 48 h post-tGCI. NaHS post-conditioning further enhanced the phosphorylation of ERK1/2 at 26, 48 and 168 h post-tGCI. Nevertheless, U0126 (an inhibitor of MEK1/2) pre-treatment reduced the p-ERK1/2 level in both the tGCI+ U0126 group and the tGCI+ U0126+ NaHS group. IHC staining revealed that p-ERK1/2-positive cell could be observed in several hippocampal subregions of the rats receiving NaHS post-conditioning. Immunofluorescence staining showed that some neurons were double-stained with p-ERK1/2 and NeuN. Furthermore, U0126 pre-treatment significantly attenuated the protective effect of NaHS post-conditioning on the neurons survival and NeuNpositive neurons in CA1 subregion. These results suggested that NaHS post-conditioning can protect hippocampal CA1 neurons from tGCI-induced injury, at least partially, through activation of ERK1/2 signaling.

Hydrogen sulfide stimulates the development of rat glioblastoma

To address the hypothesis that hydrogen sulfide (H(2)S) is a functionally significant stimulator in the development of glioblastoma (GBM) and explore the mechanism of stimulation. Forty adult Sprague-Dawley (SD) rats were given intracerebral injection of rat C6 glioma cell suspension, and an intraperitoneal injection of sodium hydrosulfide (NaHS), an exogenous H(2)S donor. The 40 rats were randomly divided into 4 groups of 10 rats in each: the control group, NaHS group, C6 glioma group (intracerebral implantation of C6 glioma cells) and C6-NaHS group (intracerebral implantation of C6 glioma cells and intraperitoneal injection of NaHS). Food and water were freely available during all phases of the experiment. Physical symptoms were observed and the tumor size was measured. Histological changes were examined by pathology. Immunohistochemical staining was used to analyze the expression of HIF-1α and integrated optical density (IOD) was used to determine the tumor microvessel density (MVD). The H(2)S content in the brain was measured. The physical symptoms of tumor-bearing rats became more serious after NaHS injection. The H(2)S level in the C6 glioma group was higher than that in the control group [(35.25 ± 1.03) nmol/g vs. (29.12 ± 0.94) nmol/g, P < 0.05], and the highest H(2)S level was found in the C6-NaHS group. The pathological examination showed that the implanted tumors were predominantly spheroid with a distinct border and no capsule could be detected. Neovascular proliferation was also observed. Foci of tumor necrosis, intratumoral hemorrhage, pseudopalisades and tumor cavity were clearly observed. The glioma cells had scant eosinophilic cytoplasm and enlarged hyperchromatic nuclei. All these phenomena were more markedly in the C6-NaHS group compared with that in other three groups. The mean tumor volume was significantly different between the C6 and C6-NaHS rats [(32.0 ± 6.9) mm(3) vs. (67.8 ± 11.9) mm(3), P < 0.001]. Immunohistochemical analysis exhibited that the hypoxia-inducible factor-1alpha (HIF-1α) and CD34 expression were significantly increased after the intraperitoneal injection of NaHS in the C6-NaHS rats (comparing the IOD between C6-NaHS group and C6 group, HIF-1α: 133 962.9 ± 451.4 vs. 38 569.8 ± 408.6, P < 0.001; CD34: 73 368.6 ± 404.8 vs. 14 570.6 ± 748.7, P < 0.001). Moreover, compared with the C6 group, there were higher MVD in the C6-NaHS group [(41.2 ± 7.9)/mm(2) vs. (97.0 ± 10.8)/mm(2), P < 0.001]. H(2)S serves as a stimulator in the development of rat glioblastoma and exogenous H(2)S strongly promotes the tumor growth. The stimulating mechanisms include the increase of HIF-1α expression and neovascular formation. H(2)S may be a significant regulator in the development of tumor.

Effects of hydrogen sulfide on the expressions of nuclear factor-κB and intercellular adhesion molecule 1 in pulmonary tissue of rats with acute lung injury

To explore the potential effects of hydrogen sulfide (H(2)S) on nuclear factor kappa B (NF-κB) and intercellular adhesion molecule 1 (ICAM-1) in lung tissue with oleic acid (OA)-induced acute lung injury (ALI) in rats. Forty-two rats were randomly divided into 3 groups: control (n = 6), OA (n = 18) and OA + NaHS (n = 18). Rats in the OA group received an intra-tail vein injection of oleic acid 0.1 ml/kg while those in the OA + NaHS group an intraperitoneal injection of NaHS 56 µmol/kg at 30 mins before OA injection. The OA and OA + NaHS groups were subdivided into 3 subgroups depending on the therapeutic duration: 2 h (n = 6), 4 h (n = 6) and 6 h (n = 6). Rats in the control group received an intra-tail vein injection of normal saline 0.1 ml/kg. Bronchioalveolar lavage fluid (BALF) was collected and the leucocytic differential count of sediment examined. The extent of lung injury was evaluated by the index of quantitative assessment (IQA). The H(2)S level in lung tissue was measured by sensitive sulphur electrode. The nuclear translocation of NF-κB and the expression of ICAM-1 in alveolar epithelial cells were measured by immunohistochemical staining. Compared with the control group, the BALF percentage of polymorphonuclear (PMN) cell was significantly higher at 2, 4 and 6 h in the OA-treated rats [(74.5 ± 3.0)%, (80.2 ± 2.0)%, (87.2 ± 2.7)% vs (3.1 ± 1.6)%, all P < 0.01]. And the value of IQA increased significantly versus those at 2, 4 and 6 h in the control group (5.2 ± 0.8, 6.4 ± 0.6, 6.8 ± 0.8 vs 0.4 ± 0.6, all P < 0.01). And the levels of H(2)S in lung tissue decreased at 2, 4 and 6 h [(21.20 ± 0.38) µmol/g, (20.80 ± 0.53) µmol/g, (18.92 ± 0.75) µmol/g vs (26.81 ± 0.65) µmol/g, all P < 0.01]. Moreover, the nuclear expression of NF-κB and the membranous expression of ICAM-1 in the alveolar epithelial cells in OA group rats was significantly higher than those of the control group (all P < 0.05). After the dosing of H(2)S donor (NaHS), the BALF percentage of PMN cell and the lung IQA decreased in the three subgroup rats (2, 4 and 6 h) versus the OA group. And the concentration of H(2)S increased significantly in the 4 h and 6 h subgroups versus the OA group at the corresponding time points. Simultaneously, the nuclear expression of NF-κB and the membranous expression of ICAM-1 in alveolar epithelial cells were significantly lower than that of the OA group at 4 h and 6 h subgroups (all P < 0.05). H(2)S may play a protective role in the ALI rats through the suppression of lung inflammation. And the inhibited expression of alveolar epithelial cell NF-κB mediates the anti-inflammatory effects of H(2)S.

Hydrogen sulfide downregulates the aortic l-arginine/nitric oxide pathway in rats

The aim of the present study was to investigate the effect of hydrogen sulfide (H(2)S) signaling by nitric oxide (NO) in isolated rat aortas and cultured human umbilical vein endothelial cells (HUVECs). Both administration of H(2)S and NaHS, as well as endogenous H(2)S, reduced NO formation, endothelial nitric oxide synthase (eNOS) activity, eNOS transcript abundance, and l-arginine (l-Arg) transport (all P < 0.01). The kinetics analysis of eNOS activity and l-Arg transport showed that H(2)S reduced V(max) values (all P < 0.01) without modifying K(m) parameters. Use of selective NOS inhibitors verified that eNOS [vs. inducible NOS (iNOS) and neuronal NOS (nNOS)] was the specific target of H(2)S regulation. H(2)S treatment (100 micromol/l) reduced Akt phosphorylation and decreased eNOS phosphorylation at Ser1177. H(2)S reduced l-Arg uptake by inhibition of a system y+ transporter and decreased the CAT-1 transcript. H(2)S treatment reduced protein expression of eNOS but not of nNOS and iNOS. Pinacidil (K(ATP) channel opener) exhibited the similar inhibitory effects on the l-Arg/NOS/NO pathway. Glibenclamide (K(ATP) channel inhibitor) partly blocked the inhibitory effect of H(2)S and pinacidil. An in vivo experiment revealed that H(2)S downregulated the vascular l-Arg/eNOS/NO pathway after intraperitoneal injection of NaHS (14 micromol/kg) in rats. Taken together, our findings suggest that H(2)S downregulates the vascular l-Arg/NOS/NO pathway in vitro and in vivo, and the K(ATP) channel could be involved in the regulatory mechanism of H(2)S.