VEGFA and ischemia: The results of this study show that, with the affection of the endogenous factors of ischemia and vascular injury in the D-gal aging mice model and exogenous factor such as electrical acupuncture excitation, EPCs are able to migrate to the site of vascular damage from the tail vein, differentiate into mature endothelial cells, and then secrete VEGF and other cytokines, thereby promoting the angiogenesis, repairing vascular injury, maintaining the environmental balance of the body, and eventually delaying aging (see Figures 4 and 5).