Kisspeptin. also known as metastin. is a naturally occurring protein in humans with crucial functions in hormone signaling during puberty and reproduction. Beyond its role in these processes. it is believed to impact mood and behavior. facilitate angiogenesis. and regulate kidney function. Furthermore. kisspeptin has been identified in the brain. where it demonstrates the ability to suppress tumor growth and metastasis (spread). However. the peptide garners the greatest scientific interest due to its notable influence on gonadotropin-releasing hormone (GnRH).