Vitamin D Receptor Gene Expression in Adipose Tissue of Obese Individuals is Regulated by miRNA and Correlates with the Pro-Inflammatory Cytokine Level

: Given the role that vitamin D (VD) plays in the regulation of the inflammatory activity of adipocytes, we aimed to assess whether obesity changes the expression of VD-related genes in adipose tissue and, if so, to investigate whether this phenomenon depends on microRNA interference and how it may influence the local inflammatory milieu. : The expression of genes encoding VD 1α-hydroxylase ( ), 24-hydroxylase ( ) and receptor ( ), selected interleukins and microRNAs was evaluated by real-time PCR in visceral (VAT) and in subcutaneous (SAT) adipose tissues of 55 obese (BMI > 40 kg/m ) and 31 normal-weight (BMI 20-24.9 kg/m ) individuals. : mRNA levels were higher, while levels were lower in adipose tissues of obese patients than in those of normal-weight controls (VAT: = 0.04, SAT: < 0.0001 and VAT: = 0.004, SAT: = 0.016, respectively). The expression of in VAT of obese subjects correlated negatively with levels of miR-125a-5p ( = 0.0006, r = -0.525), miR-125b-5p ( = 0.001, r = -0.495), and miR-214-3p ( = 0.009, r = -0.379). Additionally, mRNA concentrations in visceral adipose tissues of obese subjects correlated positively with mRNA levels of interleukins: 1β, 6 and 8. : We observed obesity-associated up-regulation of and down-regulation of mRNA levels in adipose tissue. expression correlates with the expression of pro-inflammatory cytokines and may be regulated by miRNAs.