Differential effects of organic nitrates of endothelial progenitor cells

T. Thum. Hannover Medical School, IFB, Molecular and Translational Therapeutic Strategies, 30625, Germany

Endothelial progenitor cells (EPCs) are a circulating cell population participating in vascular homeostasis in a nitric oxide-dependent manner. We investigated the effects of the nitric oxide donors isosorbide dinitrate (ISDN) and pentaerythritol tetranitrate (PETN) on EPC and endothelial function in patients with symptomatic coronary artery disease CAD. PETN treatment substantially increased numbers of circulating CD34(+)/KDR(+) EPCs (p = 0.02), whereas no effects were observed in patients treated with ISDN. EPC function assessed by formation of endothelial colonies was enhanced by twofold (p = 0.04) in patients treated with PETN. No changes were observed after ISDN treatment. Endothelial function, assessed by peripheral arterial tonometry, remained unchanged during PETN treatment, but was significantly impaired in patients treated with ISDN. Treatment of symptomatic CAD patients with PETN for 14 days significantly increased levels of circulating EPC and improved markers for EPC function, whereas ISDN was without effects on EPCs and worsened endothelial function. In the second part of the presentation we will highlight new developments about microRNA-mediated changes in EPC biology and present new miRNA-mediated treatment strategies for diseases with impaired angiogenesis