Abstract
Purpose: :
To assess vascular endothelial function in patients with ocular hypertension (OHT) or primary open-angle glaucoma (POAG) measuring generic circulating progenitor cells (CPC) and endothelial circulating progenitor cells (EPC).
Methods: :
Twenty-five patients with OHT, 25 with POAG and 25 healthy age- and gender-matched controls. underwent blood sampling for evaluation of CPC and EPC by flow cytometry. Six phenotypes of circulating progenitor cells were measured based on the surface expression of three antigens (CD34, CD133, and KDR). The population of CD34+, CD133+ and CD34+CD133+ cells were considered CPC, because expressing stem cell antigens, but lacking the endothelial lineage marker KDR. CD34+KDR+, CD133+KDR+ and CD34+CD133+KDR+ cells were considered EPCs due to the expression of the endothelial antigen.
Results: :
A marked reduction of all EPCs was found in OHT (p<0.0001) and POAG (p <0.0001) patients as compared with controls. No significant difference was detected between the OHT and the POAG groups. The reduction of CD34+KDR+ EPC, which is the most reliable EPC phenotype, in POAG (24.3±3.4) and OHT (28.0±5.0) patients as compared with controls (73.1±8.1) remained significant after adjusting for all potential confounders including age, gender, family history for cardiovascular disease (CVD), body composition, blood pressure, lipid profile, and plasma glucose and 10-year CVD risk. The level of CPC was not significantly different among the three groups. EPC levels were inversely correlated (p= 0.03) with baselineintraocular pressure.
Conclusions: :
CD34+KDR+ EPC, the most reliable EPC phenotype indicator of vascular systemic endothelial dysfunction, is severely reduced in OHT/POAG patients, without CVD or cardiovascular risk factors and no advanced age.
Keywords: intraocular pressure • flow cytometry • ischemia