Effect of short-term treatment with lercanidipine on circulating endothelial progenitor cells and structural alterations in retinal arterioles

Background: It has been previously demonstrated that dihydropyridine calcium channel blockers may possess antioxidant properties and might improve microvascular structure. The aim of the present study was therefore to investigate the effects of a short-term treatment with lercanidipine on structural alterations in retinal arterioles and on circulating endothelial progenitor cells (EPCs), which are bone marrow-derived cells possibly participating in neovascularization and endothelial protection and repair. Patients and Methods: Fourteen essential hypertensive patients were included in the study and treated for 4 weeks with lercanidipine 10-20 mg per day orally. Investigations were performed in basal condition, after appropriate wash out of previous treatments, and after 4 week lercanidipine treatment. EPCs were evaluated by flow cytometry as CD34+/CD133+/KDR+ cells. Non-invasive measurements of internal diameter (ID), external diameter (ED), wall thickness, wall to lumen ratio (W/L) and wall cross-sectional area (WCSA) of retinal arterioles using scanning laser doppler flowmetry (SLDF) were performed (Heidelberg Retina Flowmeter, Heidelberg Engineering), according to Harazny J et al, Hypertension 2007; 50:623-629. Results are summarized in the Table (*P<0.05, **p<0.01,***p<0.001 vs. Basal). A significant increase in circulating EPC count was observed after treatment with lercanidipine, associated with a reduction in W/L and an improvement of other indices of retinal artery structure, which, in the absence of a significant increase in ID, does not seem to be ascribed just to the vasodilator effect of the drug. Conclusions: For the first time, in this study, favourable effects on the EPCdependent endothelium-repair system and on alterations of retinal arterioles have been reported in men after treatment with a dihydropyridine calcium channel antagonist, lercanidipine, possibly related to hemodynamic and antioxidant properties.