Adiponectin: A New Regulator of Female Reproductive System

Abstract

Adiponectin is the hormone that belongs to the group of adipokines, chemical agents mainly derived from the white adipose tissue. The hormone plays pleiotropic roles in the organism, but the most important function of adiponectin is the control of energy metabolism. The presence of adiponectin and its receptors in the structures responsible for the regulation of female reproductive functions, such as hypothalamic-pituitary-gonadal (HPG) axis, indicates that adiponectin may be involved in the female fertility regulation. The growing body of evidence suggests also that adiponectin action is dependent on the actual and hormonal status of the animal. Present study presents the current knowledge about the presence and role of adiponectin system (adiponectin and its receptors: AdipoR1 and AdipoR2) in the ovaries, oviduct, and uterus, as well as in the hypothalamus and pituitary, the higher branches of HPG axis, involved in the female fertility regulation.

Adipokines: A gear shift in puberty

“…Thus, high levels of leptin promote onset of puberty in girls via secretion of kisspeptin, and estrogen stimulates leptin secretion additionally. Moreover, adiponectin can affect the HPG axis due to the expression of adiponectin receptors in the hypothalamus, pituitary gland, and gonads . In detail, adiponectin is a regulator of puberty onset as it inhibits the secretion of kisspeptin and GnRH in the hypothalamus and the release of GH and LH in the pituitary gland, and thereby inhibiting the onset of puberty (Figure ) .…”

“…Moreover, adiponectin can affect the HPG axis due to the expression of adiponectin receptors in the hypothalamus, pituitary gland, and gonads . In detail, adiponectin is a regulator of puberty onset as it inhibits the secretion of kisspeptin and GnRH in the hypothalamus and the release of GH and LH in the pituitary gland, and thereby inhibiting the onset of puberty (Figure ) . Individuals with obesity often have low levels of adiponectin .…”

“…In detail, adiponectin is a regulator of puberty onset as it inhibits the secretion of kisspeptin and GnRH in the hypothalamus and the release of GH and LH in the pituitary gland, and thereby inhibiting the onset of puberty (Figure ) . Individuals with obesity often have low levels of adiponectin . Sitticharoon et al showed that total adiponectin was significantly lower, whereas high molecular weight (HMW) adiponectin was significantly higher in girls with central precocious puberty (CPP) .…”

“…High leptin and low adiponectin levels can stimulate the HPG axis and therewith an early onset of puberty in boys. Nevertheless, leptin can inhibit the production of testosterone from the testes, and fat tissue can convert testosterone to estrogen (Figure ) . Both processes might result in the delay of the development of secondary sex characteristics in boys .…”

Expression and localization of adiponectin and its receptors in ovarian follicles during different stages of development and the modulatory effect of adiponectin on steroid production in water buffalo

“…Pieces of evidence also indicated the role of adiponectin in the regulation of reproduction. Studies have also demonstrated that adiponectin plays a role in the regulation of reproduction at both central and peripheral level (Dobrzyn et al, ). At the central level, adiponectin receptors AdipoR1 and AdipoR2 are expressed in hypothalamus and pituitary in human (Kubota et al, ; Rodriguez‐Pacheco et al, ).…”