The role of adiponectin in reproduction: from polycystic ovary syndrome to assisted reproduction

Abstract

Objective To summarize the effects of the adipokine adiponectin on the reproductive endocrine system, from the hypothalamic-pituitary axis to the gonads and target tissues of the reproductive system. Design A Medline computer search was performed to identify relevant articles. Setting Research institution. Intervention(s) None. Result(s) Adiponectin is a hormone secreted by adipose tissue that acts to reduce insulin resistance and atherogenic damage, but it also exerts actions in other tissues. Adiponectin mediates its actions in the periphery mainly via two receptors, AdipoR1 and AdipoR2. Adiponectin receptors are present in many reproductive tissues, including the central nervous system, ovaries, oviduct, endometrium, and testes. Adiponectin influences gonadotropin release, normal pregnancy, and assisted reproduction outcomes. Conclusion(s) Adiponectin, a beneficial adipokine, represents a major link between obesity and reproduction. Higher levels of adiponectin are associated with improved menstrual function and better outcomes in assisted reproductive cycles.

Ovarian adipocytokines are associated with early in vitro human embryo development independent of the action of ovarian insulin

“…Studies have shown that both leptin and adiponectin can regulate the hypothalamic pituitary gonadal axis independently, as well as synergistically through their interactions with each other and with other metabolically active hormones [11,18]. Specifically at the level of the human ovary, adipocytokines are implicated in the regulation of steroidogenesis by modulating the action of insulin and insulin like growth factor 1 (IGF-1) [5,12].…”

Adiponectin protects rat hippocampal neurons against excitotoxicity

“…In addition to its actions in peripheral tissues, adiponectin reportedly contributes to the central regulation of food intake and energy homeostasis ) as well as reproduction (Budak et al 2006;Michalakis and Segars 2010). Metabolic state and reproductive capacity are known to interact.…”

Adiponectine et résistine

“…En effet, l'adiponectine, AdipoR1 et AdipoR2 et la résistine sont présentes dans l'hypothalamus et l'hypophyse chez l'homme et les rongeurs (pour revue voir [18]). Des études in vitro montrent que l'adiponectine, en activant l'AMPK, réduit la sécrétion in vitro de GnRH (gonadotropin releasing hormone) par les cellules hypothalamiques GT1-7.…”

“…Une étude récente indique que l'expression d'AdipoR1 et AdipoR2 est diminuée (60 %) dans l'endomètre des femmes en échec d'implantation après une procédure de FIV (fécondation in vitro) pour infertilité comparée à l'expression dans l'endomètre de femmes fertiles [38]. D'autre part, les taux plasmatiques d'adiponectine sont fortement diminués chez des patientes atteintes de diabète gestationnel, du syndrome des ovaires polykystiques (SOPK), mais aussi d'endométriose et de cancer de l'endomètre (voir [18]). Ces études suggèrent qu'une modification de l'expression de l'adiponectine et/ou de ses récepteurs pourrait être impliquée dans la réceptivité endométriale [38,39].…”