Overexpression of the phosphoprotein enriched in diabetes gene product (Ped/pea-15) in women with polycystic ovary syndrome

OBJECTIVE To evaluate Ped/pea-15 (phosphoprotein enriched in diabetes) expression in polycystic ovary syndrome (PCOS) women. DESIGN AND PATIENTS Thirty PCOS women were studied and compared with other 30 age- and body mass index (BMI)-matched women, considered as the control group. Both patients and controls were divided according to BMI. All subjects underwent endocrine and metabolic investigation and Ped/pea-15 expression was evaluated by western blot analysis. Insulin resistance was assessed by HOMA model and insulin sensitivity index (ISI) composite. RESULTS Insulin resistance, evaluated by HOMA-R and ISI composite, was significantly higher in PCOS women and in obese controls than in normal weight controls. Ped/pea-15 expression (%) was higher in PCOS women than in controls (440.4 +/- 220.7 vs. 163.0 +/- 45.5; P < 0.001; range 145.5-987% and 97-281%, respectively), and was positively correlated with insulin, BMI, total testosterone, HOMA index, and family history (P < 0.001). In patients with PCOS univariate analysis of variance showed no effect of BMI variation (P = 0.13) on Ped/pea-15 expression levels. On multiple linear regression analysis, the major determinants of Ped/pea-15 overexpression were family history, insulin, and PCOS status independent of BMI. CONCLUSION These preliminary data (1) highlight the overexpression of Ped/pea-15 in PCOS compared to normal controls, independent of obesity; (2) suggest that Ped/pea-15 overexpression might be an early component of the metabolic syndrome in PCOS; and (3) support the hypothesis that Ped/pea-15 represents a possible useful tool to assess the presence of a genetic condition associated with insulin resistance in PCOS.