Ghrelin is an endogenous gastrointestinal hormone and neuropeptide that binds to the growth hormone (GH) secretagogue receptor (GHS-R).1,2 Ghrelin requires an n-octanoyl modification at serine 3 for binding to the growth hormone (GH) secretagogue receptor (GHS-R).3 (Des-octanoyl)-ghrelin (human) is a form of ghrelin that is lacking the octanoyl group at serine 3. It is located in the mouse stomach and is expressed at a lower level than octanoyl ghrelin.4 (Des-octanoyl)-ghrelin activates GHS-R by only 41% when used at 10 µM (IC50 = >10,000 nM; EC50 = >10,000 nM for increasing calcium accumulation).5 It induces bone marrow adipogenesis in rat models of growth hormone deficiency.6 (Des-octanoyl)-ghrelin also inhibits cell proliferation in estrogen-dependent MCF-7 breast cancer cells (EC50 = 0.81 µM) but induces proliferation of a somatotroph pituitary tumor cell line, an effect that can be blocked by MAPK, PKC, and tyrosine kinase inhibitors.7,8WARNING This product is not for human or veterinary use.
