乳酸菌对IPEC-J2细胞黏着斑激酶磷酸化及紧密连接蛋白Occludin表达的影响

Study of Lactobacillus Influence the FAK Phosphorylation and Tight Junction Protein Occludin Expression of IPEC-J2 Cells

本试验旨在探讨嗜酸乳杆菌(LAB1)如何影响黏着斑激酶(FAK)磷酸化及紧密连接蛋白Occludin的表达。用高(1.0×109 CFU·mL-1)、中(1.0×108 CFU·mL-1)、低(1.0×107 CFU·mL-1)3种浓度的致病性大肠杆菌(Escherichia coli,E.coli)和霍乱沙门菌(Salmonella choleraesuis,S.cho)对猪空肠上皮细胞系(IPEC-J2)进行感染后,用高、中、低3种浓度的LAB1作用于感染后的IPEC-J2(模拟治疗试验),用Western blotting检测FAK第397位酪氨酸磷酸化水平;用ELISA方法检测Occludin表达水平。结果显示:在LAB1模拟治疗S.cho感染的试验中,FAK磷酸化水平和Occludin的表达量与LAB1浓度呈正浓度效应,而与S.cho浓度呈负浓度效应;3种浓度的LAB1处理中、低浓度S.cho感染时,组间相互比较差异显著(P<0.05)。在LAB1模拟治疗E.coli感染的试验中,FAK磷酸化水平和Occludin表达量与LAB1浓度呈正浓度效应,3种浓度的LAB1处理低浓度E.coli感染时,组间相互比较差异显著(P<0.05)。结论:LAB1激活受E.coli和S.cho抑制的FAK磷酸化,并能上调细胞紧密连接蛋白Occludin的表达。

This experiment was conducted to study the influence of Lactobacillus acidophilus（LAB1） on the focal adhesion kinase（FAK） phosphorylation and tight junction protein occludin expression.IPEC-J2 cells were infected by three concentrations of pathogenic Escherichia coli（E.coli） and Salmonella choleraesuis（S.cho）,and then treated with LAB1.Occludin protein level was detected by ELISA,and FAK（Y397） phosphorylation was detected by Western blotting.Results were as follows： In LAB1 treated S.cho test,Occludin protein and FAK phosphorylation levels were positive correlated with the LAB1 concentration,but were negative correlated with S.cho concentration,and the differences were significant among groups that treated by mid and low concentrations of S.cho（P0.05）;In LAB1 treated E.coli test,Occludin protein and the level of FAK phosphorylation were positively correlated with LAB1 concentration,and the differences were significant among groups that treated by low concentrations of E.coli（P0.05）.Conclusion： LAB1 can activate the phosphorylation of FAK which inhibited by E.coli and S.cho,and raise regulate the cells occludin expression.