title: Ghrelin stimulates angiogenesis in human microvascular endothelial cells: Implications beyond GH release.
abstract: Ghrelin, a peptide hormone isolated from the stomach, releases growth hormone and stimulates appetite. Ghrelin is also expressed in pancreas, kidneys, cardiovascular system and in endothelial cells. The precise role of ghrelin in endothelial cell functions remains unknown. We examined the expression of ghrelin and its receptor (GHSR1) mRNAs and proteins in human microvascular endothelial cells (HMVEC) and determined whether ghrelin affects in these cells proliferation, migration and in vitro angiogenesis; and whether MAPK/ERK2 signaling is important for the latter action. We found that ghrelin and GHSR1 are constitutively expressed in HMVEC. Treatment of HMVEC with exogenous ghrelin significantly increased in these cells proliferation, migration, in vitro angiogenesis and ERK2 phosphorylation. MEK/ERK2 inhibitor, PD 98059 abolished ghrelin-induced in vitro angiogenesis. This is the first demonstration that ghrelin and its receptor are expressed in human microvascular endothelial cells and that ghrelin stimulates HMVEC proliferation, migration, and angiogenesis through activation of ERK2 signaling.
authors.affiliation: Department of Medicine, Division of Gastroenterology, VA Long Beach Healthcare System, The University of California, Irvine, 5901 E 7th Street, Long Beach, CA 90822, USA.
authors.forename: Aihua
authors.initials: A
authors.lastname: Li
authors.forename: Guangli
authors.initials: G
authors.lastname: Cheng
authors.forename: Geng Hui
authors.initials: GH
authors.lastname: Zhu
authors.forename: Andrzej S
authors.initials: AS
authors.lastname: Tarnawski
mesh_terms: D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000187:drug effects / Q000502:physiology*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D054439:Ghrelin; D013006:Growth Hormone / Q000378:metabolism*; D006801:Humans; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000502:physiology*; D008833:Microcirculation / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D018919:Neovascularization, Physiologic / Q000187:drug effects / Q000502:physiology*; D036361:Peptide Hormones / Q000008:administration & dosage* / Q000378:metabolism*; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*; D054440:Receptors, Ghrelin
chemical_list: D054439:Ghrelin; D036361:Peptide Hormones; D043562:Receptors, G-Protein-Coupled; D054440:Receptors, Ghrelin; D013006:Growth Hormone; D048049:Extracellular Signal-Regulated MAP Kinases