基于TLR4/MyD88/NF-κB信号通路观察白藜芦醇对炎症相关性结直肠癌的影响

Observing the effect of resveratrol on colitis-associated colorectal cancer based on TLR4/MyD88/NF-κB signaling pathway

目的基于Toll样受体4/髓样分化因子88/核转录因子κB(TLR4/MyD88/NF-κB)信号通路探究白藜芦醇(Res)对炎症相关性结直肠癌(CAC)的影响。方法小鼠随机分为对照组(Control)、模型组(Vehicle)、低浓度Res组(Res low)、高浓度Res组(Res high)。利用氧化偶氮甲烷/葡聚糖硫酸钠(AOM/DSS)构建小鼠CAC模型,并分别给予Res和蒸馏水灌胃治疗。比较各组小鼠结直肠肿瘤数目和结直肠状态;ELISA检测血清白介素(IL)-1β、IL-6、IL-10和肿瘤坏死因子-α(TNF-α)水平;免疫组化染色检测结直肠组织环氧化酶2(COX-2)、Ki-67、E-钙黏蛋白(E-cadherin)蛋白水平;qRT-PCR和Western blotting法检测结直肠组织TLR4、MyD88、NF-κB水平。结果与Control组比较,Vehicle组小鼠结直肠肿瘤增多、结肠组织损伤严重,血清TNF-α、IL-1β、IL-6水平明显升高(P<0.05),结直肠组织COX-2、Ki-67、TLR4、MyD88、NF-κB表达水平升高(P<0.05),IL-10、E-cadherin表达水平降低(P<0.05)。与Vehicle组比较,Res low组、Res high组上述指标均有所缓解,具有明显的Res剂量依赖性(P<0.05)。结论Res可通过抑制TLR4/MyD88/NF-κB通路,降低结直肠炎症反应,抑制结直肠癌的恶性增殖和转移,从而减轻CAC小鼠肠道损伤。

Objective To explore the effect of resveratrol(Res)on colitis-associated colorectal cancer(CAC)based on Toll-like receptor 4/myeloid differential factor 88/nuclear factor kappa B(TLR4/MyD88/NF-κB)signaling pathway.Methods Mice were divided into Control group,Vehicle group,low-concentration Res group(Res low)and high-concen⁃tration Res group(Res high).Azoxymethane/Dextran Sodium Sulfate(AOM/DSS)was used to construct mice CAC model.Mice in the groups were treated with Res and distilled water by gavage,respectively.The number of colorectal tumors and colorectal status of mice in each group were compared;ELISA was used to detect interleukin(IL)-1β,IL-6,IL-10 and tu⁃mor necrosis factor-α(TNF-α)levels in serum;Immunohistochemical staining was used to detect cyclooxygenase-2(COX2),Ki-67,E-cadherin protein levels in colorectal tissue;qRT-PCR and Western blotting was used to detect TLR4,MyD88,NF-κB levels in colorectal tissue.Results Compared with the Control group,the number of colorectal tumors was increased,and colon tissue damage was severe in the Vehicle group.The serum levels of TNF-α,IL-1βand IL-6 were in⁃creased in the Vehicle group,so as the expression levels of COX-2,Ki-67,TLR4,MyD88 and NF-κB in colorectal tissue.The expression levels of IL-10 and E-cadherin in colorectal tissue were decreased in the Vehicle group(P<0.05).Com⁃pared with the Vehicle group,the above indicators in Res low group and the Res high group were all relieved,which was ob⁃viously Res dose-dependent(P<0.05).Conclusion Res could reduce colonic inflammatory response,inhibit malignant pro⁃liferation and metastasis of colorectal cancer,thereby alleviating intestinal damage in CAC mice by inhibiting TLR4/MyD88/NF-κB pathway.