Chronic Exposure of Human Endothelial Progenitor Cells to Diabetic Condition Abolished the Regulated Kinetics Activity of Exosomes

摘要

By virtue of lifestyle change, incidence of type 2 diabetes is increasingly being raised with different up-surging pathologies. This condition found to disqualify endothelial progenitor cells during neo-vascularization. Besides to an aborted differentiation property, malfunctioned paracrine activities exacerbate vascular abnormalities. It is found nano-scaled exosomes play essential roles on reciprocal cell-cell cross-talk harboring bioactive molecules. To address the effect of diabetic serum on exosome secretion capacity, human endothelial progenitor cells were isolated from healthy volunteer and exposed to both healthy and diabetic sera for 7 days. Cell survival was assessed by the conventional MTT and Annexin V/PI staining protocol. In addition, an in vitro tubulogenesis assay, migration and LDL uptake capacity were investigated. We also measured the amount of exosomes by acetylcholine esterase activity and then expression profiles of three genes involved in exosome signaling pathway, including CD63, Alix and Rab27a, revealed by Real-time PCR method. Flow cytometry analysis showed that compared with control group necrosis level was increased by 1.6 folds in EPCs exposed to diabetic sera after 7 day (p0.01). Data showed diabetic sera not only abolished the in vitro tubulogenesis (p0.001), migration (p0.001) and LDL uptake (p0.01) properties, but also decreased release of exosomes (p0.01) and the expression of related genes (p0.01). This study shed lights on the adverse effect of diabetic condition on exosome kinetics in endothelial progenitor cells. Our findings show that diabetic condition suppresses the exosome secretion capacity by down-regulation of CD63, Alix and Rab27a genes, participating in exosome biosynthesis, trafficking and abscission, respectively.