reported that sitagliptin, a DPP-4 inhibitor, prevents the degradation of the chemokine SDF-1α and improves the recruitment of regenerative circulating CXCR4+ progenitor cells that mediate local endothelial cell proliferation without adversely affecting the structure of the vessel wall, using a mouse carotid artery injury model, and it can promote endothelial regeneration after acute endothelial injury (13). This evidence concerns the gene CXCR4 and injury.