八肽胆囊收缩素抑制LPS诱导的RAW264.7细胞AP-1活性及IL-6表达

Inhibitory effect of CCK-8 on LPS-induced IL-6 expression and AP-1 activation in RAW264.7 cells

目的研究八肽胆囊收缩素(CCK-8)对LPS诱导RAW264.7细胞IL-6表达的影响及相关机制。方法用ELISA及RT-PCR法检测RAW264.7细胞IL-6蛋白及mR-NA表达;用EMSA方法检测RAW264.7细胞AP-1 DNA结合活性。结果①LPS可时间依赖性的诱导RAW264.7细胞IL-6蛋白及mRNA表达;②10-10 mol.L-1 CCK-8对LPS诱导的RAW264.7细胞IL-6表达无明显影响;10-8、10-6 mol.L-1 CCK-8浓度依赖性地抑制了LPS诱导的RAW264.7细胞IL-6表达;③10-10 mol.L-1 CCK-8未影响LPS诱导的AP-1活性,10-8、10-6 mol.L-1 CCK-8浓度依赖性地抑制了LPS诱导的AP-1活性。结论 CCK-8通过抑制AP-1 DNA结合活性而抑制了LPS诱导的RAW264.7细胞IL-6表达,这可能是CCK-8发挥抗炎作用的信号转导机制之一。

Aim To explore the inhibitory effects of cholecystokinin octapeptide（CCK-8） on LPS-induced IL-6 expression in RAW264.7 cells and its mechanism.Methods IL-6 protein and mRNA expression in LPS-induced RAW264.7 cells were assayed by ELISA and RT-PCR,and AP-1 DNA-binding activity was tested by EMSA.Results ① The expression of IL-6 protein and mRNA were induced by LPS in a time-dependent manner in RAW264.7 cells.② 10-10 mol·L-1 CCK-8 had no effect on LPS-induced IL-6 expression in RAW264.7 cells;while 10-8,10-6 mol·L-1 CCK-8 concentration-dependently inhibited LPS-induced IL-6 expression.③ CCK-8 had no effect on LPS-induced AP-1 activation in RAW264.7 cells,while 10-8,10-6 mol·L-1 CCK-8 inhibited LPS-induced AP-1 activation in a concentration-dependent manner.Conclusion CCK-8 inhibits LPS-induced IL-6 expression in RAW264.7 cells via inhibiting AP-1 DNA-binding activity,which may be one of the mechanisms of CCK-8 anti-inflammatory effects.