title: Glucagon-like peptide-1 receptor and proglucagon expression in mouse skin.
abstract: Glucagon-like peptide-1 (GLP-1) is an insulinotropic hormone expressed by alternative post-translational processing of proglucagon in the intestines, endocrine pancreas, and brain. The multiple antidiabetogenic actions of GLP-1 include stimulation of the proliferation and differentiation of the insulin-producing beta cells in the pancreas. The GLP-1 receptor is widely distributed and has been identified in the endocrine pancreas, intestinal tract, brain, lung, kidney, and heart. Here we report the expression of the GLP-1 receptor and proglucagon in the skin of newborn mice located predominantly in the hair follicles, as well as in cultures of skin-derived cells that also express nestin, a marker of cultured cells that have dedifferentiated by epithelial to mesenchymal transition. In cultured skin cells, GLP-1 activates the MAPK/ERK signal transduction pathway, associated with cellular proliferation, differentiation, and cytoprotection. No evidence was found for the activation of cAMP or Ca2+ signaling pathways. Further, redifferentiation of cultured skin-derived cells by incubation in differentiation medium containing GLP-1 induced expression of the proinsulin-derived peptide, C-peptide. These findings suggest a possible paracrine/autocrine role for GLP-1 and its receptor in skin development and possibly also in folliculogenesis.
authors.affiliation: Laboratory of Molecular Endocrinology, Massachusetts General Hospital, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02114, United States.
authors.forename: James F
authors.initials: JF
authors.lastname: List
authors.forename: Huile
authors.initials: H
authors.lastname: He
authors.forename: Joel F
authors.initials: JF
authors.lastname: Habener
mesh_terms: D000818:Animals; D002096:C-Peptide / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D015870:Gene Expression; D052216:Glucagon-Like Peptide 1 / Q000494:pharmacology; D000067757:Glucagon-Like Peptide-1 Receptor; D007381:Intermediate Filament Proteins / Q000096:biosynthesis; D051379:Mice; D008810:Mice, Inbred C57BL; D009419:Nerve Tissue Proteins / Q000096:biosynthesis; D064231:Nestin; D052336:Proglucagon / Q000096:biosynthesis*; D018027:Receptors, Glucagon / Q000096:biosynthesis*; D012867:Skin / Q000378:metabolism*
chemical_list: D002096:C-Peptide; C000593834:Glp1r protein, mouse; D000067757:Glucagon-Like Peptide-1 Receptor; D007381:Intermediate Filament Proteins; D009419:Nerve Tissue Proteins; C577485:Nes protein, mouse; D064231:Nestin; D018027:Receptors, Glucagon; D052336:Proglucagon; D052216:Glucagon-Like Peptide 1; D048049:Extracellular Signal-Regulated MAP Kinases