IGF1 and endothelial dysfunction: IGF1 protects against endothelial dysfunction, atherosclerosis, and cardiac ischemic damage,[60] and was shown to enhance proliferation of CD34+ and mesenchymal progenitor cells.[61] In a similar manner, we and others have shown that IGFBP-3 has IGF1-independent vascular protective effects by enhancing vasoreparative functions of CD34+ cells and their mobilization from bone marrow into the circulation.[62] Increased secretion of these two factors by diabetic CD34+cells may represent a compensatory effect but clearly is not sufficient to rescue their reparative function.