Effect of L-arginine on circulating endothelial progenitor cells in hypercholesterolemic rabbits

The cardiovascular disease risk factors result in endothelial cells apoptosis and injury. Recently, endothelial progenitor cells (EPCs) have been shown to participate in ongoing endothelial repair. Nitric Oxide (NO) is essential for mobilization and functional activity of EPCs. We hypothesized that L-arginine (NO precursor) supplementation may increase EPCs number in hypercholesterolemic rabbits. EPCs, plasma levels of nitrite, von Willebrand Factor (vWF) and Intima-Media thickness ratio were determined in rabbits feeding high-cholesterol diet or high-cholesterol diet with L-arginine(3% in drinking water). L-arginine supplementation had a significant effect on the nitrite levels, and EPC numbers, and inhibited vWF increment and atherosclerosis progression (p<0.05). Our results suggest that the beneficial effect of L-arginine in prevention of atherosclerosis may be due to the modulation of EPC levels.