Obestatin
GI / Appetite Regulation (Controversial)Also known as: Obestatin
Ghrelin Gene ProductsResearch phase: Preclinical (controversial)Regulatory: Not approved. Research peptide with disputed function.
Mechanism
Obestatin is a peptide derived from the same gene as ghrelin that was initially claimed to suppress appetite — the opposite of ghrelin. However, this finding has been highly controversial and largely not replicated.
Technical detail
Obestatin is a 23-amino acid amidated peptide derived from preproghrelin processing. Initially reported (2005) to oppose ghrelin's orexigenic effects by activating GPR39, subsequent studies failed to reproduce the anorexigenic effects or confirm GPR39 as its receptor. Its physiological function remains disputed, though roles in adipocyte differentiation and glucose metabolism have been proposed.