Kisspeptin across the human lifespan:evidence from animal studies and beyond

Abstract

Since its first description in 1996, the KISS1 gene and its peptide products, kisspeptins, have increasingly become recognised as key regulators of reproductive health. With kisspeptins acting as ligands for the kisspeptin receptor KISS1R (previously known as GPR54 or KPR54), recent work has consistently shown that administration of kisspeptin across a variety of species stimulates gonadotrophin release through influencing gonadotrophin-releasing hormone secretion. Evidence from both animal and human studies supports the finding that kisspeptins are crucial for ensuring healthy development, with knockout animal models, as well as proband genetic testing in human patients affected by abnormal pubertal development, corroborating the notion that a functional kisspeptin receptor is required for appropriate gonadotrophin secretion. Given the large body of evidence that exists surrounding the influence of kisspeptin in a variety of settings, this review summarises our physiological understanding of the role of these important peptides and their receptors, before proceeding to describe the varying role they play across the reproductive lifespan.

Comparison of vaginal microbial community structure of beef cattle between luteal phase and follicular phase

“…Using culture-dependent methods, it has been shown that number of vaginal Lactobacillus spp. during follicular phase was higher than during luteal phase in rats and cattle (Otero et al 1999;Clarke et al 2016). Ovarian hormones may be the reason for the difference of vaginal microflora between follicular phase and luteal phase.…”

“…It is well known that the level of ovarian steroids changes periodically during estrus cycle, in which the level of estrogen is higher during follicular phase while level of progesterone is higher during the luteal phase. Previous studies have shown that vaginal microbial community structure is significantly different between follicular and luteal phase (Otero et al 1999;Clarke et al 2016). However, these results were based on traditional culture method in which more than 99% of the microorganisms in the ecological niches could not be cultured under laboratory conditions.…”

Evolutionary Conservation of MKRN3 and Other Makorins and Their Roles in Puberty Initiation and Endocrine Functions

“…Kisspeptin, encoded by the Kiss1 gene, is a potent activator of GnRH secretion. 7 In humans, loss-of-function mutations in KISS1 and KISS1R genes have been associated with HH. 8,9 Rare activating mutations of KISS1 and KISS1R have also been identified in patients with CPP.…”

Phoenixin and Its Role in Reproductive Hormone Release

“…Kisspeptin is a hypothalamic neuropeptide that is a key regulator of GnRH secretion. In both humans and animals, kisspeptin administration potently stimulates GnRH release, 12,13 and inactivating mutations of the kisspeptin receptor result in patients who fail to progress through puberty. 14,15 Phoenixin is expressed with the arcuate nucleus where neurons express kisspeptin 16 and thus, given these observations, the relationship between phoenixin and kisspeptin was investigated by Treen et al 9 Using two cell lines, mHypoA-GnRH/GFP and mHypoA-Kiss/GFP-3 (isolated from the Arc), the authors observed that consistent with other studies, administration of 10 and 100 nM phoenixin-20 increased GnRH-R mRNA expression, in addition to GnRH secretion.…”