endothelin-1 and sodium-bisulfide

Hydrogen sulfide (H(2)S) has recently been identified as an endogenous gaseous signaling molecule. In the vascular system, the formation of H(2)S is catalyzed by cystathionine γ‑lyase (CSE). Previous studies have demonstrated the protective effects of H(2)S on ischemic injury in various types of tissue. However,, little is known about the role of H(2)S in diabetes-associated vascular diseases. Thus, the aim of the present study was to examine the possible role of H(2)S in high glucose-induced vascular dysfunction, and to explore the underlying mechanisms. Human umbilical vein endothelial cells (HUVECs) were isolated from human umbilical veins. The levels of H(2)S following treatment with various levels of glucose were determined and the secretion of endothelin-1 (ET-1) was measured by ELISA. The mRNA and protein expression of CSE in the HUVECs was determined by real-time RT-PCR and western blot analysis, respectively. Treatment with high glucose (25 mmol/l) for 48 h significantly increased the secretion of ET-1 by HUVECs, with the concomitant suppression of H(2)S production and CSE protein expression. The increase in exogenous H(2)S levels through the administration of sodium hydrosulfide (NaHS) attenuated the high glucose-induced downregulation of CSE protein expression, and significantly inhibited the secretion of ET-1. These results suggest that the downregulation of CSE protein expression and the subsequent decrease in H(2)S production play a role in high glucose-induced vascular dysfunction possibly by increasing the secretion of ET-1 by endothelial cells.

Topics: Cell Line; Cystathionine gamma-Lyase; Endothelin-1; Gene Expression Regulation; Glucose; Human Umbilical Vein Endothelial Cells; Humans; Hydrogen Sulfide; Sulfides

To examine the effect of H2S donor, sodium hydrosulfide (NaHS), on ET-1 level in plasma and aorta in rats with atherosclerosis (AS).. Thirty male rats, weighting 200-220 g, were randomly divided into AS, AS+NaHS and control groups, n = 10 in each group.Rats were given a single dose of vitamin D3 (700 000 U/kg) in the first three days and fed with a high-cholesterol diet for 8 weeks to induce AS. Rats in AS+NaHS group were intraperitoneally injected with an H2S donor NaHS, at a dose of 56 µmol/(kg·d) for 8 weeks. At the end of the experiment for 8 weeks, all the rats were sacrificed. The plasma was collected and the aorta and coronary tissues were isolated. The atherosclerotic lesions in both aorta and coronary arteries were detected using oil red O method. H2S concentration in plasma was determined with sulfide-sensitive electrode method. ET-1 levels in plasma and aorta were calculated by radioimmunoassay kit and the localization of ET-1 in the aorta was detected by immunohistochemistry. Plasma nitric oxide synthase (NOS), endothelial NOS (eNOS), inducible NOS (iNOS) were detected with colorimetry.. AS plaque area in root of aorta of rats in AS group, AS+NaHS group and control group were (11.6±3.3)%, (1.6±1.1)%, (0.0±0.1)% respectively. The difference in AS plaque area in root of aorta among the three groups was statistically significant (F=97.675, P < 0.05). AS plaque area in coronary artery of rats in AS group, AS+NaHS group and control group were (21.4±5.7)%, (4.8±2.5)%, (0.0±0.0)% respectively. The difference in AS plaque area in coronary artery among the three groups was statistically significant (F=97.519, P < 0.05). Plasma H2S level in rats of AS group ((22.0±3.1) µmol/L) was significantly lower than that of control group ((27.9±1.0) µmol/L) and AS+NaHS group ((33.3±6.2) µmol/L, all P < 0.05). Compared with control group ((70.0±10.7) ng/L), plasma ET-1 in rats of AS group ((89.6±14.2) ng/L) and AS+NaHS group ((93.1±15.5) ng/L, P both < 0.05) were increased. However, there was no significant difference in plasma ET-1 content in rats between AS+NaHS group and AS group (P > 0.05). Compared with control group ((3.8±1.2) ng/g), ET-1 content in aorta in rats of AS group ((11.9±4.9) ng/g) and AS+NaHS group ((8.2±2.5) ng/g, both P < 0.05) were increased, and ET-1 content in aorta in rats of AS+NaHS group was decreased compared with AS group (P < 0.05). Immunochemistry results showed that ET expression in cytoplasm in aortic endothelial cells in rats of AS group was strengthened, while ET expression in rats of control group and AS+NaHS group was weak. NOS activity of rats in control group, AS group and AS+NaHS group was (25.4±5.6), (51.8±10.0) and (27.6±6.5) U/ml, eNOS activity (15.3±6.2), (4.5±2.7) and (8.7±3.9) U/ml, and iNOS activity (9.9±4.0), (47.3±10.7) and (19.0±5.2) U/ml, respectively.Differences among the three groups were statistically significant (NOS activity: F=37.231, P < 0.05, eNOS activity: F=14.600, P < 0.05, and iNOS activity: F=72.131, P < 0.05).. H2S donor NaHS reduced the AS plaque in AS rats. The mechanisms might involve the protective effect of H2S on the vascular endothelial cell, decreasing ET-1 production in aortal endothelium of atherosclerotic rats.

Topics: Animals; Aorta; Atherosclerosis; Coronary Vessels; Disease Models, Animal; Endothelin-1; Hydrogen Sulfide; Male; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Random Allocation; Rats; Sulfides

To explore the impact of hydrogen sulfide (H2S) donor, sodium hydrosulfide (NaHS), on pulmonary vascular structure and vasoactive peptides in rats with pulmonary hypertension induced by high pulmonary blood flow.. Thirty-two male Wistar rats, weighing 120-140 g, were randomly divided into shunt group (n=8), shunt + NaHS group (n=8), sham group (n=8), and sham + NaHS group (n=8). Rats in shunt group and shunt + NaHS group were subjected to an abdominal aorta-inferior vena cava shunt to create an animal model of high pulmonary flow. In the sham group and sham + NaHS group, rats experienced the same experimental processes except the shunting procedure. Rats in shunt + NaHS group and sham + NaHS group were intraperitoneally injected with an exogenous H2S donor--NaHS, at a dose of 56 micromol/(kg x d). Meanwhile, rats in shunt group and sham group were injected with the same volume of physiological saline. After 11 weeks of experiment, systolic pulmonary artery pressure (SPAP) of each rat was evaluated by using a right cardiac catheterization procedure. Heart tissues were separated as right ventricular (RV) and left ventricular plus septum (LV + SP), and the ratio of RV to LV + SP [RV/(LV + SP)] was calculated. The morphologic changes including micro-and ultra-structural changes of pulmonary arteries of rats were observed under optical microscope and electro-microscope, respectively. The percentage of muscular artery (MA) in small pulmonary arteries was calculated. The change of relative medial thickness (RMT) of pulmonary arteries was examined. H2S concentration in plasma was evaluated by modified sulfide electrode method. Endothelin-1 (ET-1), atrial natriuretic peptide (ANP), calcitonin gene related peptide (CGRP), and proadrenomedullin peptide (PAMP) were calculated by radioimmunoassay kit.. After 11 weeks of shunt, compared with sham group, SPAP increased by 48.63% (P < 0.01 ) and RV/ (LV + SP) increased by 21.95% (P < 0.01). Plasma H2S decreased significantly (P < 0.01). The percentage of MA increased significantly (P < 0.01); RMT increased significantly (P < 0.01). The changes of ultra-structure of pulmonary arteries showed that endothelial cells became swollen and desquamation, internal elastic lamina became irregular, and smooth muscular cells increased in size, showing synthetic phenotype. After the rats with shunt was administered with NaHS for 11 weeks, plasma H2S increased significantly (P < 0.01). SPAP decreased by 19.82% and RV/(LV + SP) decreased by 7.31% (P < 0.01). The percentage of MA decreased significantly and RMT decreased significantly (P < 0.01). The changes of ultra-structure of the pulmonary arteries showed lighten significantly. Plasma ET-1, ANP, and CGRP decreased significantly (all P < 0.01), whereas PAMP increased significantly than that of shunt group (P < 0.01).. The reduced production of endogenous H2S is one of mechanism of pulmonary hypertension and pulmonary vascular structure remodeling in rats with high pulmonary blood flow. H2S plays an important regulatory effect on vasoactive peptide ET-1,+ ANP, CGRP and PAMP.

Topics: Animals; Atrial Natriuretic Factor; Calcitonin Gene-Related Peptide; Disease Models, Animal; Endothelin-1; Hydrogen Sulfide; Hypertension, Pulmonary; Lung; Male; Peptides; Pulmonary Circulation; Random Allocation; Rats; Rats, Sprague-Dawley; Sulfides