Exogenous hydrogen sulfide protects human umbilical vein endothelial cells against high glucose‑induced injury by inhibiting the necroptosis pathway

Abstract

Hyperglycemia is a key factor in the development of diabetic complications, including the processes of atherosclerosis. Receptor-interacting protein 3 (RIP3), a mediator of necroptosis, is implicated in atherosclerosis development. Additionally, hydrogen sulfide (H2S) protects the vascular endothelium against hyperglycemia-induced injury and attenuates atherosclerosis. On the basis of these findings, the present study aimed to confirm the hypothesis that necroptosis mediates high glucose (HG)-induced injury in human umbilical vein endothelial cells (HUVECs), and that the inhibition of necroptosis contributes to the protective effect of exogenous H2S against this injury. The results revealed that exposure of HUVECs to 40 mM HG markedly enhanced the expression level of RIP3, along with multiple injuries, including a decrease in cell viability, an increase in the number of apoptotic cells, an increase in the expression level of cleaved caspase-3, generation of reactive oxygen species (ROS), as well as dissipation of the mitochondrial membrane potential (MMP). Treatment of the cells with sodium hydrogen sulfide (NaHS; a donor of H2S) prior to exposure to HG significantly attenuated the increased RIP3 expression and the aforementioned injuries by HG. Notably, treatment of cells with necrostatin-1 (Nec-1), an inhibitor of necroptosis, prior to exposure to HG ameliorated the HG-induced injuries, leading to a decrease in ROS generation and a loss of MMP. However, pre-treatment of the cells with Nec-1 enhanced the HG-induced increase in the expression levels of cleaved caspases-3 and -9. By contrast, pre-treatment with Z-VAD-FMK, a pan-caspase inhibitor, promoted the increased expression of RIP3 by HG. Taken together, the findings of the present study have demonstrated, to the best of our knowledge for the first time, that exogenous H2S protects HUVECs against HG-induced injury through inhibiting necroptosis. The present study has also provided novel evidence that there is a negative interaction between necroptosis and apoptosis in the HG-treated HUVECs.

<p>Hydrogen Sulfide Protects Against High Glucose-Induced Human Umbilical Vein Endothelial Cell Injury Through Activating PI3K/Akt/eNOS Pathway</p>

“…56 In a recent research, it was demonstrated that exogenous H 2 S can effectively attenuate HG-induced multiple injuries in endothelial cells. 57 Consistent with previous studies, we observed in the present research that NaHS-treatment can distinctly reduce HG-induce cytotoxicity, apoptosis, oxidative stress and inflammation in HUVECs. The present study is the first to demonstrate that HG-triggered ER stress in HUVECs can be suppressed by treatment with exogenous H 2 S. There is a recent report showing that exogenous H 2 S can alleviate cardiovascular injury by inhibiting ER stress in diabetic rats, which is consistent with our observation.…”

“…The PI3K/AKT/eNOS pathway may be not the only pathway responsible for the protective role of NaHS on glucotoxicity, and necroptosis signaling has been shown to involve in the protective role of NaHS. 57 On the other hand, PI3K/AKT/eNOS pathway is an important signaling pathway for ER stress, ROS production, inflammation and apoptosis in endothelial cells. [61][62][63][64] LY294002 had no effects on the functions of the HUVECs, which is consistent with previous findings.…”

Role of Endothelial Dysfunction in Cardiovascular Diseases: The Link Between Inflammation and Hydrogen Sulfide

“…Exposure to high glucose results in elevated ROS production and apoptosis, as well as decreased superoxide dismutase activity in endothelial cells, and all the above responses could be eliminated by pretreatment with H 2 S (Guan et al, 2012). Exogenous H 2 S alleviated the ROS overproduction and apoptosis in hyperglycemic endothelial cells through inhibiting necroptosis (Lin et al, 2018). In the aortas of diabetic rats, the connexin (Cx) 43 and 40 expressions are downregulated, while protein kinase C (PKC) and nicotinamide adenine dinucleotide phosphate-oxidase (NADPH) oxidase subunits are upregulated, H 2 S appears to be effective in attenuating these abnormalities (Zheng et al, 2010).…”

Hydrogen Sulfide (H2S)-Releasing Compounds: Therapeutic Potential in Cardiovascular Diseases

“…Endothelial dysfunction is a vital event event in the early stages of atherosclerosis ( Peng et al, 2017 ). Hyperglycemia is a key factor in the development of diabetic complications, such as atherosclerosis ( Lin J. et al, 2018 ). Receptor interacting protein 3 (RIP3) mediates necrotic apoptosis and is involved in the development of atherosclerosis.…”

“…Receptor interacting protein 3 (RIP3) mediates necrotic apoptosis and is involved in the development of atherosclerosis. NaHS significantly attenuated high-glucose (HG)-induced apoptosis of HUVECs by inhibiting the expression of RIP3 ( Lin J. et al, 2018 ). NaHS also reduces atherosclerotic plaque in rats by protecting vascular endothelial cells and reducing the production of aortic endothelium ET-1 ( Li et al, 2015d ).…”