The Effects of Leptin and Irisin on Steroidogenic Enzyme Gene Expression in Human Ovarian Granulosa Cells - Initial Studies

Fertility and energy metabolism are closely associated, and the cytokines produced by the adipose and muscle tissue play a role in this association. Leptin, predominantly produced by the white adipose tissue, and irisin, produced by the brown adipose and skeletal muscle tissues, are cytokines that are important in balancing energy metabolism. This study aimed to investigate the effects of leptin and irisin on steroidogenic enzyme gene expression in human ovarian granulosa cells in vitro. Granulosa cells were retrieved and isolated from ovarian follicular fluid during in vitro fertilization (IVF) procedures. Cells were placed in primary in vitro cultures and treated with increasing concentrations of leptin (25, 50, 100, 200, and 400 ng/ml) or irisin (125, 250, 500, 1,000, and 2,000 ng/ml) for 24, 48, and 72 hours. mRNA expression levels of CYP11A1, CYP19A1, CYP21A2, HSD3B1, and HSD17B3 were measured by qRT-PCR analysis. Leptin treatment of granulosa cells resulted in significant upregulation of CYP21A2 mRNA levels, while irisin significantly downregulated mRNA levels of CYP11A1, CYP19A1, and HSD3B1. Taken together, these early experiments demonstrate that leptin and irisin may affect steroid hormone production in the ovary by targeting the gene expression of key steroidogenic enzymes. Additional experiments are in progress.