IL-22对肠上皮细胞肠三叶因子的调控作用

Effect of IL-22 on expression of intestinal trefoil factor in intestinal epithelial cells

目的:研究白介素-22(interleukin-22,IL-22)对大鼠小肠上皮细胞(intestinal epithelial cells6,IEC-6)肠三叶因子(trefoil factor family 3TFF3)表达的影响,并探讨其可能调控机制.方法:采用不同浓度的重组大鼠IL-22(recom binant rat interleukin,rr IL-22)(1、10、100 ng m L)处理IEC-6细胞,分别培养(12、24、48 h后,RT-PCR法检测并比较处理前(0 h)及处理后不同时间点TFF3、信号转导及转录活化因子3(signal transducer and activator of transcription 3STAT3)、STAT6、细胞核因子κB(nuclear factorkappa B,NF-κB)m RNA表达变化.结果:1 ng/m L的IL-22干预IEC-6细胞12、24、48 h后TFF3和STAT3 m RNA与干预前(0 h)比较,各组间差异无统计学意义(P>0.05)10 n g/m L的I L-22干预后,随着干预时间的延长,TFF3 m RNA表达升高(P<0.05),但干预24 h与48 h差异不大;STAT3 m RNA表达量随时间的延长而升高,12 h与0 h比较差异不大(P>0.05),其余各组间比较差异有统计学意义(P<0.05).100 ng/m L组,TFF3 m RNA表达量随时间延长而显著升高,各组比较差异有统计学意义(P<0.05);STAT3 m RNA表达与干预时间的关系与10 ng/m L组相似.不同浓度组共培养12 h时,IL-22浓度100 ng/m L干预后TFF3 m RNA表达量显著升高(P<0.05),而实验中10 ng/m L干预后与1 ng/m L干预后比较表达量无明显升高(P>0.05);STAT3m R N A表达随I L-22浓度升高差异均无统计学意义(P>0.05).共培养24、48 h后,随着IL-22浓度升高,TFF3 m RNA表达量显著升高(P<0.05);STAT3 m RNA表达量随IL-22浓度升高同样升高,但100 ng/m L与10 ng/m L干预后表达量差异无统计学意义(P>0.05)而分别与1 ng/m L干预后表达量相比差异有统计学意义(P<0.05).我们尚未能测到STAT6m RNA表达,NF-κB m RNA表达量与处理前相比差异均无统计学意义(P>0.05).结论:IL-22可能通过STAT3信号转导途径上调IEC-6细胞TFF3表达,且呈明显的时间、浓度依赖性:IL-22干预的时间延长、浓度升高,STAT3和TFF3表达升高且两者升高趋势基本同步.

AIM： To investigate the effect of interleukin-22（IL-22） on the intestinal trefoil factor（ITF/TFF3） expression in IEC-6 cells and discuss the possible mechanism. METHODS： IEC-6 cells were treated with IL-22 at different concentrations（1, 10, or 100 ng/m L） for 12, 24, or 48 h. The m RNA expression of TFF3, signal transducer and activator of transcription 3（STAT3）, STAT6 and nuclear factor-κB（NF-κB） in IEC-6 cells was measured by RT-PCR.RESULTS： The m RNA expression of TFF3 and STAT3 in IEC-6 cells treated with 1 ng/m L IL-22 was not significantly up-regulated when incubated for 0, 12, 24 or 48 h（P〈0.05）. With time increasing, the m RNA expression of TFF3 in IEC-6 cells treated with 10 ng/m L IL-22 increased and the comparison between any two time points of 0, 12, 24 and 48 h showed significant differences（P〈0.05） except the comparison between the time points of 12 and 24 h; the m RNA expression of STAT3 also increased, and there were significant differences in any two time points（P〈0.05）, except between 0 and 12 h（P〈0.05）. When treated with 100 ng/m L IL-22, the m RNA expression of TFF3 in IEC-6 cells showed obvious upregulation with time increasing, and the comparison between any two time points was statistically different（P〈0.05）; the relationship between the m RNA expression of STAT3 and treatment time was the same as the group of 10 ng/m L. When IEC-6 cells were treated for 12 h, the m RNA expression of TFF3 was significantly higher in the 100 ng/m L group compared with the 1 ng/m L and 10 ng/m L groups（P〈0.05）, although there was no statistical difference between the groups of 1 ng/m L and 10 ng/m L; the m RNA expression of STAT3 did notshow a statistical difference（P〈0.05）. The m RNA expression of TFF3 in IEC-6 cells for 24 and 48 h was significantly up-regulated as the concentration of IL-22 increased, and the comparison between any two concentrations of IL-22 showed a significant difference（P〈0.05）; the m RNA expression of STAT3 was also up-regulated, showing a significant difference between any two concentrations of IL-22 except the comparison between the groups of 10 ng/m L and 100 ng/m L. We could not measure the expression of STAT6 m RNA, and the m RNA expression of NF-κB did not show a significant difference among the groups（P〈0.05）. CONCLUSION： IL-22 may up-regulate the mRNA expression of TFF3 in IEC- 6 cells through the STAT3 signal transduction pathway in a time- and dose-dependent fashion.