Role of Leptin in Reproduction

Leptin, an adipocyte hormone plays an important role in regulating energy homeostasis by inhibiting hunger, interacts with the reproductive axis of mammals at multiple sites with stimulatory effect at the hypothalamus and pituitary and its high dose has inhibitory action on steroidogenesis. As a marker whether nutrition stores are adequate, leptin may act in concert with gonadotrophins and growth hormone axis for the initiation of complex phenomenon of puberty. The expression and secretion of leptin are correlated with body fat mass and are acutely affected by feed intake. Moreover, circulating leptin increases during pubertal development in rodents and domestic animals. Effects of leptin are mediated mainly via receptor activation of the JAK-STAT pathway; however, activation of alternative pathways, such as MAP kinase, has also been reported. Leptin helps in oocyte development and maturation. It also has angiogenic, immuno-modulatory and anti inflammatory activities helps in implantation and prevents embryo rejection by the maternal immune system, invasion of trophoblast and cause mammary growth development.