Gemigliptin, a potent selective dipeptidyl peptidase 4 inhibitor, protects endothelial progenitor cells by oxidative stress via caspase-3 dependent pathway

Abstract

Endothelial progenitor cells (EPCs) are exclusive players in vasculogenesis and endothelial regeneration. EPCs are of two types and their differentiation is mediated by different growth factors. A decrease in EPC number and function causes cardiovascular abnormalities and reduced angiogenesis. Various studies has documented a role of EPCs in diabetes. EPCs treatment with different drugs improve insulin secretion but causes other abnormalities. In vivo and in vitro studies have reported anti glycation effect of gemigliptin but no data is available on in vitro effect of gemigliptin on EPC number and functional credibility. The current study was aimed to find an in vitro effect of gemigliptin on EPC number and function along with an effective treatment dose of gemigliptin. EPCs were isolated, cultured and phenotypically characterized using Dil- AcLDL and ulex-lectin fluorescence staining. EPCs were then treated with different doses of Zemiglo and their viability analyzed with viability assay using water-soluble tetrazolium salt (WST-1), by Annexin V and Propidium Iodide (PI) staining, senescence-associated beta-galactosidase (SA-β-gal) staining, western blot and Flow cytometric analysis of apoptotic signals. The results demonstrated that the isolated EPCs has typical endothelial phenotypes. And these EPCs were of two types based on morphology i.e., early and late EPCs. Gemigliptin dose dependently improved the EPCs morphology and increased EPCs viability, the most effective dose being the 20 μM. Gemigliptin at 10 μM, 20 μM and 50 μM significantly increased the BCL-2 levels and at 20 μM significantly decreased the Caspase-3 levels in EPCs. In conclusion, gemigliptin dose dependently effects the EPCs viability and morphology through Caspase-3 signaling. Our results are the first report of gemigliptin effect on EPC viability and morphology.

Keywords

• Endothelial progenitor cell
• Zemiglo
• EPC morphology
• Caspase-3