title: Insulin requires A1 adenosine receptors expression to reverse gestational diabetes-increased L-arginine transport in human umbilical vein endothelium.
abstract: Gestational diabetes mellitus (GDM) associates with increased L-arginine transport and extracellular concentration of adenosine in human umbilical vein endothelial cells (HUVECs). In this study we aim to determine whether insulin reverses GDM-increased L-arginine transport requiring adenosine receptors expression in HUVECs. Primary cultured HUVECs from full-term normal (n = 38) and diet-treated GDM (n = 38) pregnancies were used. Insulin effect was assayed on human cationic amino acid transporter 1 (hCAT1) expression (protein, mRNA, SLC7A1 promoter activity) and activity (initial rates of L-arginine transport) in the absence or presence of adenosine receptors agonists or antagonists. A1 adenosine receptors (A1AR) and A2AAR expression (Western blot, quantitative PCR) was determined. Experiments were done in cells expressing or siRNA-suppressed expression of A1AR or A2AAR. HUVECs from GDM exhibit higher maximal transport capacity (maximal velocity (V max)/apparent Michaelis Menten constant (K m), V max/K m), which is blocked by insulin by reducing the V max to values in cells from normal pregnancies. Insulin also reversed the GDM-associated increase in hCAT-1 protein abundance and mRNA expression, and SLC7A1 promoter activity for the fragment -606 bp from the transcription start point. Insulin effects required A1AR, but not A2AAR expression and activity in this cell type. In the absence of insulin, GDM-increased hCAT-1 expression and activity required A2AAR expression and activity. HUVECs from GDM pregnancies exhibit a differential requirement of A1AR or A2AAR depending on the level of insulin, a phenomenon that represent a condition where adenosine or analogues of this nucleoside could be acting as helpers of insulin biological effects in GDM.
authors.affiliation: Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago, 8330024, Chile.|Faculty of Health Sciences, Universidad San Sebastián, Concepción, 4080871, Chile.
authors.forename: Enrique
authors.initials: E
authors.lastname: Guzmán-Gutiérrez
authors.affiliation: Faculty of Health Sciences, Universidad San Sebastián, Concepción, 4080871, Chile.
authors.forename: Axel
authors.initials: A
authors.lastname: Armella
authors.affiliation: Department of Basic Sciences, Faculty of Sciences, Universidad del Bío-Bío, Chillán, 3780000, Chile.
authors.forename: Fernando
authors.initials: F
authors.lastname: Toledo
authors.affiliation: Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago, 8330024, Chile.
authors.forename: Fabián
authors.initials: F
authors.lastname: Pardo
authors.affiliation: Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago, 8330024, Chile.
authors.forename: Andrea
authors.initials: A
authors.lastname: Leiva
authors.affiliation: Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago, 8330024, Chile. sobrevia@med.puc.cl.|Department of Physiology, Faculty of Pharmacy, Universidad de Sevilla, Seville, E-41012, Spain. sobrevia@med.puc.cl.|University of Queensland Centre for Clinical Research (UQCCR), Faculty of Medicine and Biomedical Sciences, University of Queensland, Herston, QLD, 4029, Australia. sobrevia@med.puc.cl.
authors.forename: Luis
authors.initials: L
authors.lastname: Sobrevia
mesh_terms: D000293:Adolescent; D000328:Adult; D001120:Arginine / Q000378:metabolism*; D027201:Cationic Amino Acid Transporter 1 / Q000096:biosynthesis / Q000235:genetics; D016640:Diabetes, Gestational / Q000178:diet therapy / Q000188:drug therapy* / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism*; D033721:Equilibrative Nucleoside Transporter 1 / Q000378:metabolism; D005260:Female; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007231:Infant, Newborn; D007328:Insulin / Q000494:pharmacology*; D008297:Male; D011247:Pregnancy; D061251:Primary Cell Culture; D043682:Receptor, Adenosine A1 / Q000187:drug effects / Q000378:metabolism*; D014471:Umbilical Veins / Q000187:drug effects / Q000378:metabolism*; D055815:Young Adult
chemical_list: D027201:Cationic Amino Acid Transporter 1; D033721:Equilibrative Nucleoside Transporter 1; D007004:Hypoglycemic Agents; D007328:Insulin; D043682:Receptor, Adenosine A1; C420825:SLC7A1 protein, human; D001120:Arginine
keywords: Adenosine receptor; Diabetes; Endothelium; Fetal; Insulin