title: Vitamin D Storage in Adipose Tissue of Obese and Normal Weight Women.
abstract: Although vitamin D deficiency is prevalent among obese individuals, its cause is poorly understood. Few studies have measured vitamin D concentrations in adipose of obese (OB) subjects, and none have included normal weight controls (C). The goal of this study was to investigate whether the relationship between body composition, serum 25-hydroxyvitamin D (25OHD), vitamin D in subcutaneous (SQ) and omental (OM) adipose, and total adipose stores of vitamin D differ among OB and C. Obese women undergoing bariatric surgery and normal-weight women undergoing abdominal surgery for benign gynecologic conditions were enrolled. Subjects had measurements of serum 25OHD by high-performance liquid chromatography (HPLC) and body composition by dual-energy X-ray absorptiometry (DXA). Vitamin D concentrations in SQ and OM adipose were measured by mass spectroscopy. Thirty-six women were enrolled. Serum 25OHD was similar between groups (OB 27 ± 2 versus C 26 ± 2 ng/mL; p = 0.71). Adipose vitamin D concentrations were not significantly different in either SQ (OB 34 ± 9 versus C 26 ± 12 ng/g; p = 0.63) or OM compartments (OB 51 ± 13 versus C 30 ± 18 ng/g; p = 0.37). The distribution of vitamin D between SQ and OM compartments was similar between groups. Serum 25OHD was directly related to adipose vitamin D in both groups. Total body vitamin D stores were significantly greater in OB than in C (2.3 ± 0.6 versus 0.4 ± 0.8 mg, respectively; p < 0.01). In summary, although OB had significantly greater total vitamin D stores than C, the relationship between serum 25OHD and fat vitamin D and the overall pattern of distribution of vitamin D between the OM and SQ fat compartments was similar. Our data demonstrate that obese subjects have greater adipose stores of vitamin D. They support the hypotheses that the enlarged adipose mass in obese individuals serves as a reservoir for vitamin D and that the increased amount of vitamin D required to saturate this depot may predispose obese individuals to inadequate serum 25OHD. © 2016 American Society for Bone and Mineral Research.
authors.affiliation: Division of Endocrinology, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Angela
authors.initials: A
authors.lastname: Carrelli
authors.affiliation: Division of Endocrinology, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Mariana
authors.initials: M
authors.lastname: Bucovsky
authors.affiliation: Heartland Assays, LLC, Ames, IA, USA.
authors.forename: Ronald
authors.initials: R
authors.lastname: Horst
authors.affiliation: Departments of Pathology & Cell Biology and Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Serge
authors.initials: S
authors.lastname: Cremers
authors.affiliation: Division of Endocrinology, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Chengchen
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Division of Endocrinology, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Marc
authors.initials: M
authors.lastname: Bessler
authors.affiliation: Division of Endocrinology, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Beth
authors.initials: B
authors.lastname: Schrope
authors.affiliation: Division of Endocrinology, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: John
authors.initials: J
authors.lastname: Evanko
authors.affiliation: Division of Endocrinology, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Jody
authors.initials: J
authors.lastname: Blanco
authors.affiliation: Division of Endocrinology, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Shonni J
authors.initials: SJ
authors.lastname: Silverberg
authors.affiliation: Division of Endocrinology, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Emily M
authors.initials: EM
authors.lastname: Stein
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D050154:Adiposity; D000328:Adult; D001835:Body Weight; D005260:Female; D006801:Humans; D009765:Obesity / Q000378:metabolism*; D009852:Omentum / Q000378:metabolism; D050151:Subcutaneous Fat / Q000378:metabolism; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood / Q000378:metabolism*
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: BONE-FAT INTERACTIONS; DISORDERS OF CALCIUM/PHOSPHATE METABOLISM; NUTRITION