Serum asymmetric dimethylarginine, apelin, and tumor necrosis factor-α levels in non-obese women with polycystic ovary syndrome

Abstract

Polycystic ovary syndrome (PCOS) is associated with multiple risk factors for cardiovascular disease (CVD), including insulin resistance, type 2 diabetes mellitus, obesity, hypertension, and dyslipidemia. In addition, hyperandrogenism may contribute to the pathogenesis of CVD, independent of obesity and insulin resistance. We investigated serum levels of asymmetric dimethylarginine (ADMA), apelin, and tumor necrosis factor (TNF)-α as CVD risk markers and their relationship with hyperandrogenism in non-obese women with PCOS. In this study were included 82 non-obese women with PCOS and 33 controls. Women with PCOS were further divided into two groups: women with hyperandrogenism (HA-PCOS, n=37) and those without hyperandrogenism (NA-PCOS, n=45). Serum ADMA, apelin, and TNF-α levels were compared among the three groups and their relationship with hyperandrogenism was evaluated. Serum ADMA levels were significantly higher in the HA-PCOS group than in the NA-PCOS and control groups (0.45±0.09 vs. 0.38±0.08 vs. 0.40±0.07; P<0.0005). Serum TNF-α levels were significantly higher among women with PCOS compared with controls (2.91±1.25 vs. 1.74±0.77; P<0.001) and in the HA-PCOS group compared with the NA-PCOS group (3.21±1.24 vs. 2.60±1.24; P<0.0001). Both PCOS groups had significantly lower serum apelin levels compared with controls (1.31±0.54 vs. 1.16±0.34 vs. 2.78±1.10; P<0.0001). ADMA and TNF-α were positively correlated with total testosterone (r=0.219, P=0.022; r=0.332, P<0.001, respectively) and free androgen index (r=0.287, P=0.002; r=0.289, P=0.002, respectively), whereas apelin was negatively correlated with these parameters (r=−0.362, P<0.001; r=−0.251, P=0.008). These findings may indicate that non-obese women with PCOS are at an increased risk for CVD, which is further aggravated by hyperandrogenism.