Majallah-i Dānishgāh-i ̒Ulūm-i Pizishkī-i Bābul (Apr 2018)
Kisspeptin: Key Regulator of Hypothalamic–Pituitary–Gonadal Axis
Abstract
BACKGROUND AND OBJECTIVE: Gonadotropin-Releasing Hormone (GnRH) neurons of hypothalamus are final output of brain for regulation of puberty onset and hypothalamic pituitary gonadal (HPG) axis functions in mammals. However, the mechanisms responsible for release of GnRH neurons are unknown. A number of various factors including neurotransmitters, neuropeptides or different signals have been identified to be involved in the regulation of the secretion of GnRH neurons. Neuronal set of kisspeptin have been recognized recently as critical upstream regulators of GnRH neurons. Given the importance of this issue, in this study a review of various studies and sources about biosynthesis, neuroanatomy, signaling, function and dysfunction of kisspeptin was performed. METHODS: In this review study, new evidence in relation to role of kisspeptin neuropeptide in the reproductive system were investigated by using various databases including pubmed, sciencedirect, nature, springer, wiley, scopus and key words such as kisspeptin, gonads, hypothalamus, GnRH and reproduction were used. FINDINGS: From 145 gained articles, 63 articles were reviewed. Kisspeptin neuropeptide signaling in hypothalamus is required for initiation of puberty and mammalian reproductive function. Kisspeptin neurons stimulate GnRH release and act as central integrator of external and internal signals. Neurones kisspeptin are sensitive to sex steroids, metabolic cues estrogen like compounds. CONCLUSION: Kisspeptin neurons play a vital role in the maturation and function of the HPG axis, including the sexual differentiation of the brain, the timing of puberty, the regulation of gonadotropin secretion and the control of fertility by hormonal and environmental cues.
