Kisspeptin: Scientific Profile

Publicado el 12 de julio de 2026 · Actualizado el 28 de agosto de 2026

Kisspeptin (Kisspeptin-10 / KP-10; CAS 374675-21-5) is a signaling decapeptide derived from the KISS1 gene, corresponding to the C-terminal fragment 45-54 of metastin. In research models it acts as an agonist of the KISS1R receptor (GPR54), triggering the release of GnRH and regulating the reproductive axis. Material intended exclusively for research use.

Kisspeptin is a neuroendocrine peptide encoded by the KISS1 gene and recognized as one of the central regulators of the hypothalamic-pituitary-gonadal (HPG) axis. The compound most frequently studied in the laboratory is Kisspeptin-10 (KP-10), a decapeptide corresponding to residues 45-54 of the precursor protein historically known as metastin. Its chemical identity is well characterized: CAS number 374675-21-5, molecular formula C63H83N17O14, and an approximate molecular weight of 1302.46 g/mol. The sequence of the human decapeptide is Tyr-Asn-Trp-Asn-Ser-Phe-Gly-Leu-Arg-Phe with the amidated carboxyl end (YNWNSFGLRF-NH2); this C-terminal amidation, together with the Arg-Phe-NH2 motif characteristic of the RFamide peptide family, is essential for receptor affinity and activation.

From a structural standpoint, KP-10 preserves the biologically active region of the longer kisspeptins (KP-54, KP-14, and KP-13), all of which are products of proteolytic processing of the same precursor. The C-terminal decapeptide portion retains practically all of the potency at the receptor, which is why KP-10 is used as a reference tool in signaling studies. Because it is a short, non-glycosylated peptide, it is susceptible to degradation by peptidases, which conditions its relatively brief half-life in biological systems and motivates the development of analogs with greater stability.

The mechanism of action centers on the G protein-coupled receptor KISS1R, also called GPR54. The binding of kisspeptin to this receptor activates the Gq/11 pathway, with stimulation of phospholipase C beta, generation of inositol trisphosphate and diacylglycerol, mobilization of intracellular calcium, and activation of protein kinase C, in addition to MAP kinase pathways (ERK1/2). In the hypothalamus, the neurons that express KISS1R are fundamentally the neurons that produce gonadotropin-releasing hormone (GnRH). When kisspeptin activates these neurons, depolarization and release of GnRH into the hypophyseal portal system occur; this in turn stimulates the secretion of luteinizing hormone (LH) and, to a lesser extent, follicle-stimulating hormone (FSH) by the anterior pituitary. In experimental models, kisspeptin behaves as one of the most potent known stimuli for GnRH release, positioning itself "upstream" of GnRH itself in the hierarchy of the reproductive axis.

Research has also documented the role of specific neuronal populations, in particular the KNDy neurons of the arcuate nucleus, which coexpress kisspeptin, neurokinin B, and dynorphin and are considered integrators of GnRH pulse generation. The participation of the kisspeptin/KISS1R system in sex-steroid feedback, in the onset of puberty, and in peripheral signaling phenomena in tissues such as the placenta, gonads, and pancreas has also been explored. It is worth recalling that the KISS1 gene was initially described in the context of metastasis suppression (hence the name metastin), and part of the preclinical literature has examined its function in tumor biology, an area independent of the reproductive axis.

As for documented research applications, kisspeptin occupies a prominent place in experimental neuroendocrinology. It is used as a pharmacological probe to study the generation of GnRH pulses, the sensitivity of the HPG axis, and the mechanisms that govern the onset of sexual maturation. Clinical research groups—notably the one led by Waljit Dhillo at Imperial College London—have carried out human studies that characterize gonadotropin responses to kisspeptin administration, which has driven interest in its class as a tool to probe reproductive-axis disorders in a research framework. Other lines of work explore its relationship with reproductive-behavior circuits and with peripheral signaling.

The level of evidence for kisspeptin is more solid than that of many niche peptides: there is a consistent body of preclinical research and several human studies supporting its physiological role and its pharmacology at KISS1R. Nevertheless, it is worth maintaining an honest framing: much of the use remains experimental and proof-of-concept, the analogs and optimal routes of administration continue to be studied, and extrapolation between animal and human models requires caution. The chemical characterization, sequence identity and receptor mechanism are well established, while numerous specific applications remain in the phase of active research.