IL-33介导M2巨噬细胞在口腔黏膜上皮-间充质转化中的相关作用机制

Interleukin-33 enhances epithelial-to-mesenchymal transition through inducing M2 macrophages to activate TGF-β1/Smad signaling pathway of oral mucosa

目的探讨白细胞介素33(IL-33)介导M2巨噬细胞在口腔黏膜上皮-间充质转化(EMT)中的相关作用机制。方法将25只雄性BALB/c小鼠分为口腔黏膜成纤维化(OSF)组(20只)和对照组(5只)。OSF组通过槟榔碱刺激建立OSF小鼠模型,对照组使用PBS注射液在相同部位给药。观察口腔黏膜组织巨噬细胞表型、IL-33以及转化生长因子-β1(TGF-β1)/Smad通路表达水平;培养人口腔黏膜细胞并与M2巨噬细胞相互作用体外模型,使用IL-33添加剂和TGF-β受体抑制剂,观察EMT标志物表达水平。结果HE染色和Masson染色证实了口腔黏膜纤维化模型建立成功,与对照组比较,OSF组口腔黏膜组织中E-钙黏蛋白(E-cadherin)表达水平降低,波形蛋白(Vimentin)表达水平升高(均P<0.05)。此外,观察到IL-33和TGF-β水平升高以及TGF-β1/Smad通路激活,巨噬细胞在口腔黏膜组织中聚集且表型为M2巨噬细胞。与空白对照组比较,IL-33组E-cadherin水平降低,Vimentin的表达增高(均P<0.05);LY-2109761+IL-33组与IL-33组相比,E-cadherin的表达增高,Vimentin的水平降低(均P<0.05)。Western blot检测TGF-β、p-Smad2和Smad2的表达水平提示,与IL-33组相比,LY2109761+IL-33组IL-33对TGF-β有促进作用(P<0.05);IL-33组与空白对照组相比,p-Smad2水平显著提高(P<0.05);LY-2109761+IL-33组与IL-33组相比,p-Smad2水平显著降低(P<0.05)。结论IL-33通过介导M2巨噬细胞调控TGF-β1/Smad通路促进口腔黏膜上皮间质转化。

Objective Epithelial-to-mesenchymal transition(EMT)has been proven to be involved in the development and progression of fibrosis diseases.This study aims to investigate the related mechanism of Interleukin-33-induced EMT through M2 macrophages.Methods Twenty-five male BALB/c mice were divided into oral mucosal fibrosis(OSF)group with 20 mice and control group with 5 mice.In OSF group,the mouse model of OSF was established by arecoline stimulation,and the expression levels of macrophage phenotype,IL-33 and transforming growth factor-β1(TGF-β1)/Smad(small mothers against Decappentaplegic)in oral mucosa were observed.The human oral mucosa cells were cultured and interacted with M2 macrophages in vitro.IL-33 additive and TGF-βreceptor inhibitor were used to observe the expression level of EMT markers.Results The model of OSF mice was successfully established and confirmed by HE stain and Masson's trichrome stain.At the same time,we found evidence in support of EMT,such as decreased protein levels of E-cadherin and elevated levels of Vimentin in the oral mucosa(P<0.05).Additionally,the increasing of IL-33 and TGF-βlevels as well as TGF-β1/Smad signaling activation was observed(P<0.05).Macrophages were recruited to the oral mucosa and identified as M2 macrophages.Compared with the blank control group,level of E-cadherin in IL-33 group decreased and the expression of Vimentin increased(all P<0.05).Compared with IL-33 group,the expression of E-cadherin in LY-2109761+IL-33 group increased and the level of Vimentin decreased(all P<0.05).The expression levels of TGF-β,p-Smad2 and Smad2 were detected by Western blot.Compared with IL-33 group,IL-33 in LY2109761+IL-33 group promoted TGF-β(P<0.05).Compared with the blank control group,the level of p-Smad2 in IL-33 group was significantly increased(P<0.05).Compared with IL-33 group,the level of p-Smad2 in LY-2109761+IL-33 group decreased significantly(P<0.05).Conclusion IL-33 conducts M2 macrophages activating TGF-β1/Smad signaling pathway to promote EMT of the oral mucosa.