Abstract：This experiment was to investigate the effects of threonine on the activity and proliferation of rat intestinal epithelial cells, and to explore whether threonine had regulation effect on tight junction protein expression of rat intestinal epithelial cells. Rat intestinal epithelial cell line IEC-6 cells were treated with different concentrations (0, 0.1, 0.5, 1.0, 5.0 and 10.0 mmol/L) of threonine for 24 h. The IEC-6 cell activity was determined using MTT method, the IEC-6 cell proliferation was observed through hematoxylin and eosin (HE) staining, and the expression of IEC-6 cell tight junction proteins claudin-3 and occludin were tested by Western-blot method. The results showed that different concentrations of threonine could increase the IEC-6 cell activity in varying degree, and the IEC-6 cell activity was the highest after explored to 0.5 mmol/L threonine for 24 h, and it significantly higher that the control group which not treated by threonine (P<0.05). IEC-6 cell proliferation also was enhanced by different concentrations of threonine, and the 0.5 mmol/L threonine group had best effect. Compared with the control group which not treated by threonine, threonine with the concentration of 0.1 mmol/L had no effect on the tight junction protein claudin-3 expression (P>0.05), but significantly increased the occludin expression (P<0.05). Compared with the control group which not treated by threonine, threonine with the concentrations of 0.5, 1.0, 5.0 and 10.0 mmol/L significantly increased the occludin and claudin-3 expression, the relative expression level of claudin-3 increased by 1.84, 7.08, 8.71 and 3.83 times, respectively, and the relative expression level of occluding increased by 2.65, 2.71, 2.82 and 3.88 times, respectively. In conclusion, threonine with properly concentration can improve the activity and proliferation of IEC-6, and 0.5 mmol/L threonine has the most significant effect. Meanwhile, the 0.5 mmol/L threonine up-regulates the expression of tight junction proteins claudin-3 and occludin.
任曼, 黄金歌, 靳二辉, 车传燕, 胡倩倩, 周金星, 李升和. 苏氨酸对大鼠小肠上皮细胞系IEC-6细胞活性和紧密连接蛋白表达的影响[J]. 动物营养学报, 2018, 30(10): 4081-4086.
REN Man, HUANG Jin, JIN Erhui, CHE Chuanyan, HU Qianqian, ZHOU Jinxing, LI Shenghe. Effects of Threonine on Activity and Tight Junction Protein Expression of Rat Intestinal Epithelia Cell Line IEC-6 Cell. Chinese Journal of Animal Nutrition, 2018, 30(10): 4081-4086.
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