title: Expression of adiponectin receptors in pancreatic beta cells.
abstract: Pancreatic beta cell dysfunction is an early and crucial pathogenic factor in the development of type 2 diabetes. Free fatty acids (FFA) and adipokines released from adipose tissues lead to both the development of insulin resistance and beta cell dysfunction. Adiponectin is a novel adipokine with antidiabetic properties. Its circulating concentrations are reduced in subjects with increased visceral adiposity, insulin resistance, or type 2 diabetes. Very recently, the cloning of two adiponectin receptors AdipoR1 and AdipoR2 was reported. AdipoR1 is abundantly expressed in muscle, while AdipoR2 is predominantly expressed in liver. Here we report the marked expression of mRNAs for the adiponectin receptors AdipoR1 and AdipoR2 in human and rat pancreatic beta cells, at levels similar to liver and greater than muscle. Adiponectin receptor expression is increased by beta cell exposure to the unsaturated FFA oleate, and treatment of insulin-producing cells with globular adiponectin induces lipoprotein lipase expression. Regulated adiponectin receptor expression on pancreatic beta cells might be a novel mechanism modulating the effects of circulating adiponectin.
authors.affiliation: Laboratory of Experimental Medicine, Université Libre de Bruxelles, Brussels, Belgium.
authors.forename: Ilham
authors.initials: I
authors.lastname: Kharroubi
authors.forename: Joanne
authors.initials: J
authors.lastname: Rasschaert
authors.forename: Décio L
authors.initials: DL
authors.lastname: Eizirik
authors.forename: Miriam
authors.initials: M
authors.lastname: Cnop
mesh_terms: D052242:Adiponectin; D000818:Animals; D002478:Cells, Cultured; D005230:Fatty Acids, Nonesterified / Q000378:metabolism*; D006801:Humans; D007328:Insulin / Q000096:biosynthesis; D036341:Intercellular Signaling Peptides and Proteins; D007375:Interleukin-1 / Q000378:metabolism*; D007515:Islets of Langerhans / Q000378:metabolism*; D008074:Lipoproteins / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D009132:Muscles / Q000378:metabolism; D009928:Organ Specificity; D011506:Proteins / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D054419:Receptors, Adiponectin; D011956:Receptors, Cell Surface / Q000378:metabolism*; D013045:Species Specificity
chemical_list: C475418:ADIPOR1 protein, human; C475420:ADIPOR2 protein, human; D052242:Adiponectin; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D036341:Intercellular Signaling Peptides and Proteins; D007375:Interleukin-1; D008074:Lipoproteins; D011506:Proteins; D054419:Receptors, Adiponectin; D011956:Receptors, Cell Surface