Abdominal subcutaneous fat gene expression and circulating levels of leptin and adiponectin in polycystic ovary syndrome

Abstract

To determine leptin and adiponectin serum levels and gene expression in subcutaneous adipose tissue from women with polycystic ovary syndrome (PCOS) and nonhirsute, ovulatory women; and leptin/adiponectin (L/A) ratio. Case-control study. University hospital gynecologic endocrinology unit. Thirty-one women with PCOS and 57 controls. Anthropometric, hormonal, and metabolic assessment; subcutaneous adipose tissue biopsy. Leptin and adiponectin serum levels, L/A ratio, controlled by age, and gene expression in women with PCOS and controls, stratified by body mass index and variables associated with androgen excess and insulin resistance. Serum leptin was higher in overweight/obese patients with PCOS than in all normal-weight control women. Adiponectin levels were similar in all subgroups. The L/A ratio was lower in normal-weight controls (1.80; range 0.94-3.72) than in overweight/obese controls (5.27; range 2.66-13.58) and patients with PCOS (7.73; range 3.81-15.04). Subcutaneous leptin messenger RNA was higher in overweight/obese women with PCOS than in normal-weight controls (2.316 [range 1.987-2.580] vs. 1.687 [range 1.518-2.212]). Adiponectin gene expression was similar in all groups. Positive correlations were found between serum and messenger RNA levels for both leptin and adiponectin. On multiple regression analysis, percentage of body fat contributed significantly to L/A ratio in PCOS, independently of body mass index and free androgen index. In PCOS, altered adipocyte secretion seems to relate to adiposity rather than to androgen excess.