Effect of Leptin on the Steroidogenesis of Cultured Human Granulosa Cells

Abstract

Objective: To elucidate the location of leptin and leptin receptors of ovary specimens obtained from patients undergoing hysterectomy by immunohistochemical staining and to determine the effect of leptin on the steroidogenesis of cultured granulose cells. Method: In the culturing process of the granulose cells, FSH (1 IU/ml) and leptin (50 ng/ml), IGF-I (50 ng/ml) was administered to each study group (Group 1: FSH; Group II: FSH, leptin; Group III: FSH, IGF-I; Group IV: FSH, IGF-I, leptin), and the levels of estradiol, progesterone, androstenedione in the culture media was measured by radioimmunoassay. Statistical analysis was conducted by one-way ANOVA with Scheffe test. Results: The results showed that leptin and leptin receptors were both found to be strongly stained in granulose and theca cells, and also in some interstitial cells, and also in some interstitial cells. Lepin receptors were also observed in cultured granulose cells. While there was no statistically significant difference in the androstenedione concentrations between the groups, estradiol concentrations was significantly decreased in Group IV (2202.0±151.14 pg/ml) compared to Group III (2859,0±122.6 pg/ml), and progesterone concentrations were also significantly decreased in Group II (4696.3±190.6 ng/ml) and Group IV (4517±206.78 ng/ml) compared to Group III (5546.0±179,5 ng/ml). Conclusion: The study result of this study suggest that leptin is directly involved in the regulation of ovarian functions, in particular steroidogenesis.