Oxidative stress and nitric oxide in polycystic ovary syndrome

Abstract

Polycystic ovary syndrome (PCOS) is a common endocrine disorder affecting 5–10% of premenopausal women. In addition to its well-established reproductive effects, PCOS is a metabolic disorder characterised by insulin resistance, hyperandrogenism and dyslipidaemia but the effects of these disturbances on oxidative stress and nitric oxide metabolism are not known. We thus sought to compare measures of oxidative stress and nitric oxide metabolites in patients with PCOS and healthy volunteers (HV). Preliminary data from banked frozen plasma samples obtained from a phenotypically detailed cohort of PCOS patients (age 29.4 ± 6.6 years, BMI 33.2 ± 7.4 kg/m 2 ) and age/BMI-matched HV showed similar nitrite (PCOS [ n = 25] 153 ± 16.57 nmol/l, HV [ n = 17] 187.8 ± 26.59nmol/l, p = NS) but lower nitrate levels in subjects with PCOS (PCOS [ n = 33] 7.3 ± 1.92 μmol/l, HV [ n = 27] 24.54 ± 2.59μmol/l, p < 0.001). The PCOS and control group displayed similar lipid profiles (TC: 4.79 ± 0.1 and 4.5 ± 0.06, HDL: 1.35 ± 0.1 and 1.38 ± 0.05 and LDL: 2.93 ± 0.15 and 2.76 ± 0.15, respectively). Plasma nitrite correlated inversely with LDL concentrations in subjects with PCOS ( r = −0.531, p < 0.05) but not in HVs. There were no significant relationships between plasma nitrate and lipid levels. Inspired by these results, data will be presented at this meeting from a fresh group of subjects in which these parameters are compared in the context of an increased free radical formation (detected as direct spin-trapping of lipid-derived radicals in patient blood) and ORAC status that result from dysfunctional lipid metabolism within PCOS. Abbreviatons: PCOS, polycystic ovary syndrome; HV, healthy volunteers; NS, non-significant; TC, total cholesterol; HDL, high-density lipoprotein; LDL, low-density lipoprotein; ORAC, oxygen radical absorbance capacity.