Dataset Information

FokI polymorphism in vitamin D receptor gene: Differential expression of TNFα in peripheral mononuclear cells of type 2 diabetic subjects.

ABSTRACT:

Introduction

FokI polymorphism has been associated with obesity and type 2 diabetes (T2D) in some populations.

Objective

To investigate the frequencies of a genetic polymorphism of Vitamin D receptor (FokI) in patients with T2D and control subjects and investigate the role of 1,25(OH)₂D₃ in the expression of pro-inflammatory markers in peripheral blood mononuclear cells (PBMCs).

Methods

The case-control study was conducted in 160 patients with T2D and 160 control subjects, men and women (30-74 years old). The genotype and allele frequency of FokI polymorphisms were determined in these subjects. Subsequently a subgroup of 40 subjects was included from which PBMCs were removed. In vitro, the culture medium was supplemented with two different concentrations of 1,25(OH)₂D₃(10^- 8 M and 10^- 10 M). The expression profiles of TNFα and mRNA were analysed by qPCR, and GAPDH and β-actin were used as housekeeping genes.

Results

The control subjects have an increased frequency of the FF genotype. In subjects with T2D, the ff genotype was associated with higher HOMA-IR values than individuals with genotype Ff (p = 0.021). In vitro study in PBMCs showed differential expression of TNFα mRNA by FokI genotype, with a lower expression of this marker of inflammation in FF genotype subjects at a concentration of 10^- 8 M of 1,25(OH)₂D₃.

Conclusion

Our data suggest that VDR FokI polymorphism is associated with T2D, and the genotypes Ff and ff of this variant show a reduced response or resistance to the anti-inflammatory action of VitD, which could indicate a functional role of FokI polymorphism of VDR.

SUBMITTER: Angel B

PROVIDER: S-EPMC5963422 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Publications

<i>FokI</i> polymorphism in vitamin D receptor gene: Differential expression of TNFα in peripheral mononuclear cells of type 2 diabetic subjects.

Angel Bárbara B Lera Lydia L Sánchez Hugo H Oyarzún Amaya A Albala Cecilia C

Meta gene 20151027

<h4>Introduction</h4><i>FokI</i> polymorphism has been associated with obesity and type 2 diabetes (T2D) in some populations.<h4>Objective</h4>To investigate the frequencies of a genetic polymorphism of Vitamin D receptor (<i>FokI</i>) in patients with T2D and control subjects and investigate the role of 1,25(OH)<sub>2</sub>D<sub>3</sub> in the expression of pro-inflammatory markers in peripheral blood mononuclear cells (PBMCs).<h4>Methods</h4>The case-control study was conducted in 160 patients ...[more]

PMID: 30941281

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