Currently and worldwide, a high prevalence of obesity, obesity-associated metabolic dysfunction, and vitamin D (VD) deficiency occurs. Besides participating in bone mineralization and calcium homeostasis, VD has other major functional roles. The vitamin D receptor (VDR) signaling pathway is crucial for the proper functioning of adipose tissue (AT). AT is a reservoir for VD and can activate/inactivate VD by hydroxylation. Subcutaneous and visceral AT (SAT, VAT) have different and prime roles in metabolic regulation/dysfunction. A search was done on PubMed/Medline, Web of Science, and Scopus databases using the following keywords: vitamin D, vitamin D receptor, hydroxylases, subcutaneous adipose tissue, visceral adipose tissue, obesity, and metabolic dysfunction. Our chapter focuses on human studies on VD status and expression of VDR and VD activation/inactivation enzymes in SAT and VAT in an obese environment.
Part of the book: Adiposity