Expression of Leptin (Ob Gene Product) in Reproductive System with Special Reference to Polycystic Ovary Syndrome
Purpose: To determine serum leptin and its ob mRNA expression both in the PCOS and non-PCOS ovary, endometrium and adipose tissue in normal or polycystic ovary syndrome (PCOS) in South Indian population. PCOS (Polycystic Ovary Syndrome) and non-PCOS subject’s endometrium, ovary and adipose tissue were investigated using a reverse transcription-competitive polymerase chain reaction method to quantify the mRNA levels of leptin and compared with normal weight control adipose tissue. Results: Endometrium, ovary and adipose tissue ob mRNA levels were highly correlated with serum leptin, BMI and body fat distribution of 80 subjects (10 normal weight, 8 thin PCOS, 8 thin non-PCOS, 7 overweight PCOS, 7 overweight non-PCOS, 10 obese PCOS, 10 obese non-PCOS, 10 morbidly obese PCOS and 10 morbidly obese non-PCOS). Ob mRNA levels were positively correlated with serum levels of dehydroepiandrosterone sulphate, free testosterone, luteinizing hormone, and prolactin. Ob mRNA level was inversely correlated with SHBG and androstenedione. Conclusion: Here, we report for the first time in Indian population, that endometrium, ovary, adipose tissue ob mRNA levels and serum leptin are highly correlated and are different in expression levels in thin, obese, morbidly obese PCOS and non-PCOS, when compared to individuals with normal weight. The leptin could be a novel, independent risk factor for PCOS.
Keywords: Ob mRNA, Serum leptin, body mass index, body fat distribution, infertility, ovary.