Endothelial progenitor cells in polycystic ovary syndrome according to insulin resistance status

Aim Polycystic ovary syndrome (PCOS) is associated with increased cardiovascular disease (CVD) risk, particularly with insulin resistance (IR). Endothelial progenitor cells (EPCs) contribute to vascular repair. This study evaluated circulating EPC number in women with anovulatory PCOS with and without IR, and its relationship with cardiovascular risk markers. Methods In this cross-sectional study, 40 newly diagnosed, treatment-naïve women with anovulatory PCOS (2003 Rotterdam criteria) were divided into two groups of 20 according to the presence or absence of IR (HOMA-IR ≥2.7), and compared with 20 age- and sex-matched healthy controls. Circulating EPCs (CD34+/CD133+/VEGFR-2+ cells) were quantified by flow cytometry. Metabolic, hormonal and inflammatory parameters, together with serum VEGF, ICAM-1, VCAM-1, E-selectin and MMP-9, were measured by ELISA. Results Glucose, triglyceride, hs-CRP, fibrinogen, ferritin, E-selectin and MMP-9 were significantly higher, and HDL-cholesterol significantly lower, in the IR-positive group compared with controls (P < .05). ICAM-1 and VEGF did not differ significantly among groups. In the IR-negative group, VCAM-1 was the only inflammatory or endothelial marker significantly higher than in controls (P = .010). Circulating EPC numbers did not differ significantly between either PCOS group and controls, and EPC counts correlated weakly with FSH (Spearman rho=0.258, P = .046; exploratory). Conclusion In young, newly diagnosed women with PCOS, inflammatory and endothelial-activation markers were increased predominantly in the IR-positive group, which also had a higher BMI, so the effects of IR and adiposity cannot be separated. Circulating EPC numbers did not differ significantly between groups; larger studies with functional EPC assays are needed.