Endothelial dysfunction underlies the basic pathophysiology of microvascular complications of diabetes. Endothelial dysfunction is associated with impaired nitric oxide (NO) availability. Since NO production is tightly regulated by endothelial nitric oxide synthase (eNOS), several therapeutic strategies have been investigated and proposed to improve eNOS bioavailability in the vasculature. The findings of Cheng et al. suggest that increased availability of eNOS may be an effective strategy in restoring endothelial function in patients with diabetic nephropathy.