Kisspeptin

Kisspeptin (Kisspeptin-10 / Metastin 45-54) is a neuropeptide encoded by the KISS1 gene that plays a pivotal role in the neuroendocrine regulation of reproduction through activation of the GPR54 receptor (KISS1R). It is the primary upstream regulator of GnRH (gonadotropin-releasing hormone) neurons in the hypothalamus, making it the master switch for the hypothalamic-pituitary-gonadal (HPG) axis. Kisspeptin binding to KISS1R triggers Gq/11-mediated signaling cascades in GnRH neurons, resulting in GnRH pulse generation, which subsequently drives LH and FSH secretion from the anterior pituitary. Research applications include fundamental studies on puberty onset mechanisms, the role of metabolic status in fertility (kisspeptin neurons receive leptin and insulin signals), polycystic ovary syndrome (PCOS) models, hypogonadotropic hypogonadism investigation, and the neurobiology of the GnRH pulse generator. Clinical research has utilized kisspeptin to trigger ovulation in IVF protocols and to diagnose reproductive endocrine disorders. The peptide is also being studied for its roles in placental implantation, cancer metastasis suppression (originally identified as a metastasis suppressor), and cardiovascular function.