Autophagy regulation of rat bone marrow-derived endothelial progenitor cells and cell functions

Objective To investigate the effect of autophagy regulation of rat bone marrow-derived endothelial progenitor cells (EPCs) on cell functions. Methods EPCs isolated from rat bone marrow were treated with rapamycin ( 10 μg/L), 3-MA (5 mmol/L) or wortmannin (50 nmol/L) for 24 hours. Cell migration was assayed using a 24-well transwell cell culture chamber. Tube formation was assayed on GFR (growth factor-reduced) -Matrigel. Angiogenic cytokine was analyzed by using corresponding ELISA kits. Expression of the autophagy marker protein LC3-Ⅱ, LAMP2A and HSC70 were analyzed by Western blotting. Results 10 μg/L rapamycin treatment inhibited EPCs migration, tube formation and secretion of angiogenic cytokines. EPCs function significantly increased following 5 mmol/L 3-MA or 50 nmol/L wortmannin treatment. Western blotting showed that rapamycin increased LC3-Ⅱprotein expression, but reduced LAMP2A and HSC70 expression. 3-MA or wortmannin treatment reduced LC3-Ⅱprotein expression (P<0.05), while increased LAMP2A and HSC70 expression. Conclusions Moderate inhibition of autophagy promotes the function of EPCs probably by reducing LC3-Ⅱprotein levels. Key words: Autophagy; Animals experimention; Endothelial progenitor cells