Effects Of Down-Regulating Aquaporin3Gene Expression On Intestinal Mucosal Barrier By RNA Interference

Objective：To explore the effect of down-regulating AQP3gene expression onintestinal mucosal barrier by RNA interference and the possible mechanism.Methods：AQP3expression in Caco-2cells were analyzed. A lentiviral vectorinterfering AQP3expression was constructed and infected Caco-2cells. Stabletransfected Caco-2cell line was established and the interference efficiency of AQP3was identified by quantitative RT-PCR and Western blot. Intestinal mucosal barrierwas established in vitro and Caco-2cells were divided into three groups: CON group,NC group, RNAi group. TEER、Lucifer yellow permeability and E.coli C25crossingthe monolayer were measured at7,14,21days respectively. Western blot andimmunocytochemistry were used to check the expression of Occludin, Claudin-1proteins.Results: The analysis of quantitative RT-PCR and Western blotting showed that theexpression of AQP3was substantially down-regulated by RNAi．Compare withBLANK group, TEER was decreased at7,14,21days, Lucifer yellow permeabilityand the amount of bacterial (E.coli C25) crossing the monolayer were increasedsignificantly（P﹤0.05). Western blot analysis revealed the expression level ofOccludin and Claudin-1protein were significantly decreased. Immunocytochemistryshowed Occludin and Claudin-1were mainly distributed in the cytoplasm and cytomembrane and the structure of the tight junction was destroyed.Conclusions: Targeted AQP3gene silence could decrease the intestinal mucosalbarrier integrity significantly. Paving the way for further explore the treatment ofintestinal mucosal barrier injury.