Neuropeptide Cyclo-Prolylglycine: Discovery, Pharmacological Effects, and Mechanism of Action

This article is a review of studies on the endogenous neuropeptide cyclo-prolylglycine (CPG), which was discovered in Russia in 1996 and subsequently confirmed by numerous international researchers. Cyclo-Pro-Gly is a prominent representative of the regulatory oligopeptide group of glyprolines, the development of which was initiated by Academician I.P. Ashmarin. The article describes the broad spectrum of pharmacological activities of CPG, including nootropic, antihypoxic, neuroprotective, anxiolytic, antidepressant-like, antithrombotic, analgesic, anti-addictive, and antitumor effects. Two possible mechanisms of action for CPG are discussed: regulation of the homeostasis of insulin-like growth factor-1 and modulation of glutamatergic AMPA receptors, followed by the activation of neurotrophin tyrosine kinase receptors.