Kisspeptin

Kisspeptin is a peptide signaling system that plays a central role in reproductive neuroendocrinology through signaling at the KISS1R (GPR54) receptor. Human genetics and physiology studies support its importance in hypothalamic-pituitary-gonadal axis regulation.

Kisspeptins are peptide products of the KISS1 gene, with several biologically active fragment lengths reported in the literature (including kisspeptin-54). These peptides act through KISS1R, a G-protein-coupled receptor expressed in reproductive regulatory pathways.

Kisspeptin signaling stimulates gonadotropin-releasing hormone (GnRH) neuronal pathways and downstream luteinizing hormone (LH) release. Loss-of-function human mutations in KISS1R are linked with hypogonadotropic hypogonadism, and experimental administration in humans increases gonadotropin responses. Mechanistic details of pulsatility and desensitization remain active research topics.

Early clinical. The human translational signal is strong for reproductive hormone physiology, but therapeutic use remains indication-specific and is still being defined. Current evidence supports biological relevance more strongly than broad clinical efficacy claims across infertility contexts.

• Pubertal and reproductive axis regulation
• Hypogonadotropic hypogonadism pathophysiology
• Ovulation and assisted-reproduction hormone triggering strategies
• Neuroendocrine control of GnRH/LH pulsatility

Clinical studies are generally smaller than late-phase drug programs, and responses vary by sex, diagnosis, and dosing paradigm. Some mechanistic findings are context-dependent, and long-term comparative outcome data are limited.

• de Roux N, Genin E, Carel JC, Matsuda F, Chaussain JL, Milgrom E. Hypogonadotropic hypogonadism due to loss of function of the KiSS1-derived peptide receptor GPR54. Proceedings of the National Academy of Sciences of the USA. 2003;100(19):10972-10976. doi:10.1073/pnas.1834399100.
• Messager S, Chatzidaki EE, Ma D, et al. Kisspeptin directly stimulates gonadotropin-releasing hormone release via G protein-coupled receptor 54. Proceedings of the National Academy of Sciences of the USA. 2005;102(5):1761-1766. doi:10.1073/pnas.0409330102.
• Dhillo WS, Chaudhri OB, Patterson M, et al. Kisspeptin-54 stimulates the hypothalamic-pituitary gonadal axis in human males. Journal of Clinical Endocrinology and Metabolism. 2005;90(12):6609-6615. doi:10.1210/jc.2005-1468.