Exogenous H ₂ S reverses high glucose-induced endothelial progenitor cells dysfunction via regulating autophagy

Abstract

This study aims to determine the effect of exogenous hydrogen sulfide (H 2 S) under high glucose (HG)-induced injury in endothelial progenitor cells (EPCs), and to explore the possible underlying mechanisms. Mononuclear cells were isolated from the peripheral blood of healthy volunteers by density-gradient centrifugation and identified as late EPCs by immunofluorescence and flow cytometry. EPCs were treated with high concentrations of glucose, H 2 S, Baf-A1, 3-MA or rapamycin. Cell proliferation, cell migration and tube formation were measured using cell counting kit-8, Transwell migration and tube formation assays, respectively. Cellular autophagy flux was detected by RFP-GFP-LC3, and Western blotting was used to examine the protein expression levels of LC3B, P62, and phosphorylated endothelial nitric oxide synthase (eNOS) at Thr495 (p-eNOS Thr495 ). Reactive oxygen species (ROS) levels were measured using a DHE probe. H 2 S and rapamycin significantly reversed the inhibitory effects of HG on the proliferation, migration, and tube formation of EPCs. Moreover, H 2 S and rapamycin led to an increase in the number of autophagosomes accompanied by a failure in lysosomal turnover of LC3-II or p62 and p-eNOS Thr495 expression and ROS production under the HG condition. However, Baf-A1 and 3-MA reversed the effects of H 2 S on cell behavior. Collectively, exogenous H 2 S ameliorated HG-induced EPC dysfunction by promoting autophagic flux and decreasing ROS production by phosphorylating eNOS Thr495 .

Deciphering The Emerging Role of Programmed Cell Death in Diabetic Wound Healing

“…Melatonin can promote autophagy and inhibit ECs apoptosis in an autophagy-dependent manner 93 . Ma et al reported that exogenous hydrogen sulfide ameliorated high glucose-induced EPCs dysfunction by promoting autophagy 94 . In addition, activation of autophagy also plays an important role in the induction of angiogenesis.…”

Hydrogen Sulfide: A Key Role in Autophagy Regulation from Plants to Mammalians

“…The protective effect of sulfide in several illnesses has been linked to its role promoting autophagy which may decrease ROS production. In a recent study in endothelial progenitor cells (EPCs), exogenous H 2 S ameliorated the high glucose (HG)-induced injury by promoting autophagic flux and decreasing ROS production, demonstrating the protecting role of sulfide under this dysfunction [ 62 ]. Their findings demonstrated that the phosphorylation of the endothelial nitric oxide synthase (eNOS) at Thr495 determines whether this enzyme produces either NO or superoxide, and sulfide reduced the phosphorylation level of this enzyme, decreasing NO and ROS production [ 62 ].…”