Serum 25-Hydroxyvitamin D and Adipose Tissue Vitamin D Receptor Gene Expression: Relationship With Obesity and Type 2 Diabetes

• Published in: The journal of clinical endocrinology and metabolism Vol. 100; no. 4; pp. E591 - E595
• Main Authors: Clemente-Postigo, Mercedes, Muñoz-Garach, Araceli, Serrano, Marta, Garrido-Sánchez, Lourdes, Bernal-López, M. Rosa, Fernández-García, Diego, Moreno-Santos, Inmaculada, Garriga, Nuria, Castellano-Castillo, Daniel, Camargo, Antonio, Fernández-Real, Jose M., Cardona, Fernando, Tinahones, Francisco J., Macías-González, Manuel
• Format: Journal Article
• Language: English
• Published: United States Oxford University Press 01.04.2015; Copyright by The Endocrine Society
• Subjects: 25-Hydroxyvitamin D; Adipose tissue; Adipose Tissue - metabolism; Adult; Aged; Body fat; Body Mass Index; Calcitriol; Carbohydrate metabolism; Cells, Cultured; Cohort Studies; Diabetes; Diabetes mellitus (non-insulin dependent); Diabetes Mellitus, Type 2 - blood; Diabetes Mellitus, Type 2 - genetics; Explants; Female; Gene Expression; Glucose metabolism; Homeostasis; Humans; Insulin resistance; Male; Metabolism; Middle Aged; Obesity; Obesity - blood; Obesity - genetics; Overweight - blood; Overweight - genetics; Parathyroid hormone; Prediabetic State - blood; Prediabetic State - genetics; Receptors, Calcitriol - genetics; Receptors, Calcitriol - metabolism; Vitamin D; Vitamin D - analogs & derivatives; Vitamin D - blood; Vitamin D Deficiency - blood; Vitamin D Deficiency - genetics; Vitamin D receptors; Vitamin D3; Vitamin deficiency
• DOI: 10.1210/jc.2014-3016
• ISSN: 0021-972X; 1945-7197

Context: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.Design and Patients: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/m2) 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.Setting:University Hospital.Main Outcome Measures: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.