甲状腺素对猪小肠上皮细胞miR-let-7a基因表达及细胞增殖的影响

miR-let-7a在动物细胞的分化、增殖与凋亡等方面发挥越来越重要的作用。甲状腺激素(TH)作用非常广泛,机体的每个细胞几乎都是TH作用的靶细胞,其可以促进组织分化、生长和成熟。本实验用甲状腺素(T4)浓度分别为(0、0.02、0.03、0.05、0.075、0.1、0.2μmol/L)在体外培养猪的小肠上皮细胞。结果表明:T4处理组的细胞体积形态相对于空白对照组没有明显变化;当T4添加浓度为0.03μmol/L时,细胞的增殖率显著低于其他组(P0.05);当T4浓度为0~0.03μmol/L时,let-7a的表达随着添加剂量的增加而升高,浓度从0.03~0.2μmol/L变化时,let-7a的表达呈现降低趋势,浓度为0.03μmol/L时表达量极显著高于其他组(P0.01)。let-7a的表达量与细胞增殖呈负相关。

Effects of Thyroxine on miR-let-7a Gene Expression and Cell Proliferation in Small Intestinal Epithelial Cells

miR-let-7a plays an important role in the differentiation, proliferation and apoptosis of animal cells. The impact of thyroid hormone is very extensive, almost every cell of the body is the target of thyroid hormone, which can promote the differentiation, growth and maturation of the tissue. In this study, The effects of thyroxine were investigatied(T4) on the regulation of miR-let-7a gene expression and proliferation of small intestinal epithelial cells. The cells were cultured in different concentrations of T4(0,0.02, 0.03, 0.05, 0.075, 0.1, 0.2 mmol/L). The results showed that the expression of let-7a increased with the increased dosage of T4 from 0 to 0.03 μmol/L, the expression decreased, from 0.03 to 0.2 μmol/L. The expression is significantly higher than that of other groups(P<0.01) at the concentration is 0.03 mmol/L, while the cell proliferation rate was significantly lower than that of other concentration group(P<0.05).The expression of let-7a was negatively correlated with the cell proliferation.