Kisspeptin-10 is a naturally occurring protein in humans that plays an important role in hormone signalling during puberty and reproduction. It is also thought to alter mood and behaviour, promote angiogenesis, and regulate kidney function. The peptide has also been found in the brain and suppresses tumour growth and metastasis (spread). The peptide is of greatest scientific interest for its ability to influence gonadotropin-releasing hormone (GnRH).