Details

Autor(en) / Beteiligte

• Best, Cora M
• Riley, Devon V
• Laha, Thomas J
• Pflaum, Hannah
• Zelnick, Leila R
• Hsu, Simon
• Thummel, Kenneth E
• Foster-Schubert, Karen E
• Kuzma, Jessica N
• Cromer, Gail
• Larson, Ilona
• Hagman, Derek K
• Heshelman, Kelly
• Kratz, Mario
• de Boer, Ian H
• Hoofnagle, Andrew N

Titel

Vitamin D in human serum and adipose tissue after supplementation

Ist Teil von

• The American journal of clinical nutrition, 2021-01, Vol.113 (1), p.83-91

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2021

Quelle

Oxford Journals 2020 Medicine

Beschreibungen/Notizen

• Serum 25-hydroxyvitamin D [25(OH)D] concentration is an indicator of vitamin D exposure, but it is also influenced by clinical characteristics that affect 25(OH)D production and clearance. Vitamin D is the precursor to 25(OH)D but is analytically challenging to measure in biological specimens. We aimed to develop and validate a liquid chromatography–tandem mass spectrometry (LC-MS/MS) method for quantification of vitamins D3 and D2 in serum and to explore the potential of circulating vitamin D as a biomarker of exposure in supplementation trials. The method was validated using guideline C62-A from the Clinical and Laboratory Standards Institute and was applied in 2 pilot clinical trials of oral vitamin D3 supplementation. Pilot study 1 included 22 adults randomly assigned to placebo or 2000 IU/d. Blood was collected at baseline, 1, 3, 6, and 12 mo. Pilot study 2 included 15 adults randomly assigned to 2000 or 4000 IU/d. Blood and subcutaneous (SUBQ) adipose tissue were collected at baseline and 3 mo. In study 1, mean change (baseline to 3 mo) in serum vitamin D3 was −0.1 ng/mL in the placebo group and 6.8 ng/mL in the 2000 IU/d group (absolute difference: 6.9; 95% CI: 4.5, 9.3 ng/mL). In study 2, mean change (baseline to 3 mo) in serum vitamin D3 was 10.4 ng/mL in the 2000 IU/d group and 22.2 ng/mL in the 4000 IU/d group (fold difference: 2.15; 95% CI: 1.40, 3.37). Serum and adipose tissue vitamin D3 concentrations were correlated, and the dose-response of vitamin D3 in adipose mirrored that in serum. We validated a sensitive, robust, and high-throughput LC-MS/MS method to quantify vitamins D3 and D2 in serum. Serum and SUBQ adipose tissue vitamin D3 concentrations increased proportionally to dose with 3 mo of daily supplementation. These trials were registered at clinicaltrials.gov as NCT00552409 (pilot study 1) and NCT01477034 (pilot study 2). ▪