title: Dehydroepiandrosterone increases beta-cell mass and improves the glucose-induced insulin secretion by pancreatic islets from aged rats.
abstract: The effect of dehydroepiandrosterone (DHEA) on pancreatic islet function of aged rats, an animal model with impaired glucose-induced insulin secretion, was investigated. The following parameters were examined: morphological analysis of endocrine pancreata by immunohistochemistry; protein levels of insulin receptor, IRS-1, IRS-2, PI 3-kinase, Akt-1, and Akt-2; and static insulin secretion in isolated pancreatic islets. Pancreatic islets from DHEA-treated rats showed an increased beta-cell mass accompanied by increased Akt-1 protein level but reduced IR, IRS-1, and IRS-2 protein levels and enhanced glucose-stimulated insulin secretion. The present results suggest that DHEA may be a promising drug to prevent diabetes during aging.
authors.affiliation: Department of Physiology and Biophysics, ICB, USP, São Paulo, SP, CEP05389-970, Brazil.
authors.forename: Mayrin C
authors.initials: MC
authors.lastname: Medina
authors.forename: Lílian C
authors.initials: LC
authors.lastname: Souza
authors.forename: Luciana C
authors.initials: LC
authors.lastname: Caperuto
authors.forename: Gabriel F
authors.initials: GF
authors.lastname: Anhê
authors.forename: Angélica M
authors.initials: AM
authors.lastname: Amanso
authors.forename: Vicente P A
authors.initials: VP
authors.lastname: Teixeira
authors.forename: Silvana
authors.initials: S
authors.lastname: Bordin
authors.forename: Angelo R
authors.initials: AR
authors.lastname: Carpinelli
authors.forename: Luiz R G
authors.initials: LR
authors.lastname: Britto
authors.forename: Renato L
authors.initials: RL
authors.lastname: Barbieri
authors.forename: Maria I
authors.initials: MI
authors.lastname: Borella
authors.forename: Carla R O
authors.initials: CR
authors.lastname: Carvalho
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000375:Aging / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D000818:Animals; D048429:Cell Size / Q000187:drug effects*; D003687:Dehydroepiandrosterone / Q000008:administration & dosage*; D003920:Diabetes Mellitus / Q000188:drug therapy / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D007328:Insulin / Q000378:metabolism*; D055504:Insulin Receptor Substrate Proteins; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000378:metabolism* / Q000473:pathology; D047908:Intracellular Signaling Peptides and Proteins; D008297:Male; D019869:Phosphatidylinositol 3-Kinases / Q000096:biosynthesis; D010750:Phosphoproteins / Q000096:biosynthesis; D051057:Proto-Oncogene Proteins c-akt; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000276:Adjuvants, Immunologic; C526292:IRS1 protein, human; C526297:IRS2 protein, human; D007328:Insulin; D055504:Insulin Receptor Substrate Proteins; D047908:Intracellular Signaling Peptides and Proteins; C526296:Irs1 protein, rat; C526299:Irs2 protein, rat; D010750:Phosphoproteins; D003687:Dehydroepiandrosterone; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt