kisspeptin13

Kisspeptin-13 (KP-13) is a peptide of 13 amino acids belonging to the kisspeptin family, derived from the Kiss1 gene. Kisspeptins are endogenous ligands for the G protein–coupled receptor GPR54 (KISS1R) and play a central role in activating the hypothalamic–pituitary–gonadal axis. KP-13 is one of several peptide products generated by proteolytic processing of Kiss1-derived precursors, including longer forms such as kisspeptin-54 and kisspeptin-14.

Mechanism of action: KP-13 binds to KISS1R on gonadotropin-releasing hormone (GnRH) neurons in the hypothalamus, promoting GnRH secretion. This leads to increased luteinizing hormone (LH) and follicle-stimulating hormone (FSH) release from the pituitary and downstream effects on gonadal function. In animal studies and some human research, kisspeptins are critical for puberty onset and for the regulation of reproductive function. The potency and pharmacology of KP-13 relative to other kisspeptin isoforms have been explored, with several reports indicating strong GnRH-stimulating activity for KP-13.

Distribution and detection: KP-13 is expressed in hypothalamic neurons and, in some contexts, has been detected in peripheral tissues or circulation, though levels can be labile and influenced by physiological state and assay sensitivity.

Clinical and research relevance: KP-13 is primarily studied as a tool to understand kisspeptin signaling and as a potential target for treating reproductive disorders. There are no approved clinical uses for KP-13 at present; much of the evidence comes from preclinical studies and early-phase human research.