Departamento De Farmacología and CIBER, Facultad De Medicina, Universidad De Valencia, Valencia, Spain.
FISABIO, Valencia, Spain.
J Steroid Biochem Mol Biol. 2020 Sep;202:105720. doi: 10.1016/j.jsbmb.2020.105720. Epub 2020 Jun 18.
The synonymous single nucleotide polymorphism (SNP) rs731236, located in the vitamin D receptor (VDR) gene (Taq I) has been associated with both decreased levels of the protein in peripheral blood mononuclear cells and a fibrosis-related complication in Crohn´s disease (CD). Interactions between VDR and a protein-disulfide isomerase-associated 3 (PDIA3) in the regulation of extracellular matrix have been reported and we aim to analyze the relevance of the VDR genotypes and the effects of Vitamin D (VD) in the expression of VDR, PDIA3 and proliferation of intestinal fibroblasts. Human intestinal fibroblasts were isolated from the non-affected surgical resections of colorectal patients and classified according to the VDR genotype. In some cases, cells were transfected with specific PDIA3 siRNA. Basal and VD-stimulated expression of VDR, PDIA3 and Collagen 1A1 (COL1A1) as well as fibroblast migration/proliferation were analyzed. Our data show that intestinal fibroblasts homozygous for the C allele in the VDR gene exhibited lower VDR protein levels and higher proliferation than cells homozygous for the T allele. VD increased VDR and attenuated the accelerated proliferation of CC fibroblasts. The diminished VDR level detected in CC cells was associated with increased levels of both PDIA3 and COL1A1 expression and the transient silencing of PDIA3 significantly reduced COL1A1 expression. We conclude that intestinal fibroblasts homozygous for the C allele in the VDR gene exhibited: reduced VDR protein levels, increased proliferation and increased PDIA3/COL1A1 expression. Treatment with VD increased VDR and attenuated proliferation of these cells.
同义单核苷酸多态性（SNP）rs731236 位于维生素 D 受体（VDR）基因（Taq I）中，与外周血单个核细胞中蛋白水平降低以及克罗恩病（CD）的纤维化相关并发症有关。已经报道了 VDR 与细胞外基质调节中的蛋白质二硫键异构酶相关 3（PDIA3）之间的相互作用，我们旨在分析 VDR 基因型的相关性以及维生素 D（VD）对 VDR、PDIA3 和肠成纤维细胞增殖表达的影响。从结直肠患者的非病变手术切除部位分离出人肠成纤维细胞，并根据 VDR 基因型进行分类。在某些情况下，用特异性 PDIA3 siRNA 转染细胞。分析基础状态和 VD 刺激下 VDR、PDIA3 和胶原 1A1（COL1A1）的表达以及成纤维细胞迁移/增殖。我们的数据表明，VDR 基因中 C 等位基因纯合的肠成纤维细胞的 VDR 蛋白水平较低，增殖速度高于 T 等位基因纯合的细胞。VD 增加了 VDR，并减弱了 CC 成纤维细胞的加速增殖。在 CC 细胞中检测到的 VDR 水平降低与 PDIA3 和 COL1A1 表达水平的增加有关，而 PDIA3 的瞬时沉默显著降低了 COL1A1 的表达。我们得出结论，VDR 基因中 C 等位基因纯合的肠成纤维细胞表现出：VDR 蛋白水平降低、增殖增加和 PDIA3/COL1A1 表达增加。VD 治疗增加了 VDR 并减弱了这些细胞的增殖。
