title: Serum 25-hydroxyvitamin D and adipose tissue vitamin D receptor gene expression: relationship with obesity and type 2 diabetes.
abstract: BACKGROUND
  The relationship between 25-hydroxyvitamin D [25(OH)D] and obesity and type 2 diabetes is not completely understood. Vitamin D receptor (VDR) expression in adipose tissue (AT) is related to obesity and might be regulated by 1,25-dihydroxyvitamin D3 [1,25(OH)2D3].
  
  
  OBJECTIVE
  To analyze serum 25(OH)D and VDR gene expression in AT according to body mass index (BMI) and glycemic status and the effect of 1,25(OH)2D3 on AT according to BMI.
  
  
  METHODS
  Two cohorts were studied: 1) 118 subjects classified according to their BMI (lean, overweight, obese, or morbidly obese [MO]) and their glycemic status (normoglycemic [NG] and prediabetic and diabetic [P&D]); and 2) 30 obese subjects (BMI > 30 kg/m(2)) classified as NG and P&D. VDR gene expression was analyzed during preadipocyte differentiation and in vitro stimulation with 1,25(OH)2D3 of AT explants from donors with different BMI values.
  
  
  METHODS
  University Hospital.
  
  
  METHODS
  Serum 25(OH)D, parathyroid hormone (PTH), and AT VDR gene expression.
  
  
  RESULTS
  25(OH)D levels were lower in P&D than NG subjects, significantly so in the lean and MO groups (P < .05). 25(OH)D levels correlated negatively with homeostasis model of assessment for insulin resistance (HOMA-IR) (r = -0.200; P = .032) and glucose (r = -0.295; P = .001), but not with BMI. VDR gene expression was higher in MO than in the other BMI groups (P < .05). 1,25(OH)2D3 increased VDR gene expression in AT from obese patients (P < .05) but not from lean subjects.
  
  
  CONCLUSIONS
  25(OH)D levels are diminished in P&D compared to NG subjects, independently of BMI, and are closely related to glucose metabolism variables, suggesting that vitamin D deficiency is associated more with carbohydrate metabolism than with obesity. Moreover, AT has a different response to 1,25(OH)2D3 depending on the degree of obesity.
authors.affiliation: Unidad de Gestión Clínica Endocrinología y Nutrición (M.C.-P., A.M.-G., L.G.-S., D.F.-G., D.C.-C., F.C., F.J.T., M.M.-G.), Instituto de Investigación Biomédica de Málaga (IBIMA), Complejo Hospitalario de Málaga (Virgen de la Victoria)/Universidad de Málaga, 29010 Málaga, Spain; Centro de Investigación Biomédica En Red, Pathophysiology of Obesity and Nutrition (CB06/03) (M.C.-P., L.G.-S., D.F.-G., A.C., J.M.F.-R., F.C., F.J.T., M.M.-G.), 28029, Madrid, Spain; Service of Diabetes, Endocrinology, and Nutrition (M.S., N.G., J.M.F.-R.), Institut d'Investigació Biomédica de Girona, 17007 Girona, Spain; Biomedical Research Laboratory (M.R.B.-L.), Internal Medicine Department, IBIMA, Regional University Hospital of Malaga (Carlos Haya Hospital), Universidad de Málaga, 29010 Málaga, Spain; Área del Corazón del Complejo Hospitalario de Málaga (Virgen de la Victoria) (I.M.-S.), IBIMA/Universidad de Malaga, Red de Investigación Cardiovascular, 29010 Málaga, Spain; and Lipid and Atherosclerosis Research Unit (IMIBIC) (A.C.), Reina Sofia University Hospital, University of Cordoba, 14004 Cordoba, Spain.
authors.forename: Mercedes
authors.initials: M
authors.lastname: Clemente-Postigo
authors.forename: Araceli
authors.initials: A
authors.lastname: Muñoz-Garach
authors.forename: Marta
authors.initials: M
authors.lastname: Serrano
authors.forename: Lourdes
authors.initials: L
authors.lastname: Garrido-Sánchez
authors.forename: M Rosa
authors.initials: MR
authors.lastname: Bernal-López
authors.forename: Diego
authors.initials: D
authors.lastname: Fernández-García
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Moreno-Santos
authors.forename: Nuria
authors.initials: N
authors.lastname: Garriga
authors.forename: Daniel
authors.initials: D
authors.lastname: Castellano-Castillo
authors.forename: Antonio
authors.initials: A
authors.lastname: Camargo
authors.forename: Jose M
authors.initials: JM
authors.lastname: Fernández-Real
authors.forename: Fernando
authors.initials: F
authors.lastname: Cardona
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Tinahones
authors.forename: Manuel
authors.initials: M
authors.lastname: Macías-González
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D000328:Adult; D000368:Aged; D015992:Body Mass Index; D002478:Cells, Cultured; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000235:genetics*; D005260:Female; D015870:Gene Expression; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood* / Q000235:genetics*; D050177:Overweight / Q000097:blood / Q000235:genetics; D011236:Prediabetic State / Q000097:blood / Q000235:genetics; D018167:Receptors, Calcitriol / Q000235:genetics* / Q000378:metabolism; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000235:genetics
chemical_list: D018167:Receptors, Calcitriol; D014807:Vitamin D; C104450:25-hydroxyvitamin D