Neuropeptide Y (NPY) is a 36-amino-acid polypeptide belonging to the pancreatic polypeptide family; it is widely distributed throughout the mammalian central and peripheral nervous systems and ranks among the most abundant neuropeptides. It was first identified in porcine brain tissue by Tatemoto et al. in 1982. NPY exerts a wide range of physiological functions by binding to G protein-coupled receptors; the receptor subtypes identified in humans include Y1R, Y2R, Y4R, and Y5R. NPY is one of the most potent orexigenic (appetite-stimulating) factors known and plays a central role in the hypothalamic regulation of energy balance.
Furthermore, it plays significant roles in learning and memory, epilepsy, stress responses, neuroprotection, and the regulation of cardiovascular function. Recent research has highlighted NPY receptors as promising targets for anti-obesity drugs, with studies on their structure and function providing a crucial foundation for the development of novel therapies. In the periphery, NPY has also been found to exert anti-obesity effects by maintaining thermogenic adipose tissue. Pathologically, NPY is closely associated with various conditions-such as hypertension, neurodegenerative diseases (e.g., Alzheimer's disease and Parkinson's disease), and obstructive sleep apnea syndrome-demonstrating potential as both a disease biomarker and a therapeutic target.
