樟芝多糖通过CD4+CD25+Foxp3+调节性T细胞对小鼠非酒精性脂肪性肝病的保护作用

Protective Effect of Polysaccharide from Antrodia Camphorata on NAFLD Mice via CD4+CD25+Foxp3+ Treg

关键词:  樟芝多糖  调节性T细胞  非酒精性脂肪性肝病

Key words:  antrodia camphorate  regulatory T-cell (Treg)  non-alcoholic fatty liver disease(NAFLD)

摘要:

目的 研究樟芝多糖通过CD4⁺CD25⁺Foxp3⁺调节性T细胞（Treg）的调控对小鼠非酒精性脂肪性肝病（NAFLD）的保护作用。方法 高脂饮食构建小鼠NAFLD模型，设置对照组、模型组、低剂量组、高剂量组。樟芝多糖干预1~4周中每周流式细胞术检测外周血Treg细胞的比例，谷丙转氨酶（ALT）、谷草转氨酶（AST）的表达，外周血中转化生长因子β（TGF-β）、白介素-6（IL-6）的表达。樟芝多糖干预4周后，小鼠处死，取肝脏进行油红染色，Western blot法检测肝组织中TGF-β和Foxp3、Smad3蛋白的表达，RT-qPCR检测IL-6、TGF-β、Foxp3、Smad3的mRNA表达。结果 高脂饮食喂养4周后成功构建NAFLD小鼠模型，且模型组中Terg比例显著低于对照组（P<0.05），樟芝多糖干预后Treg比例相比模型组显著增高（P<0.05），小鼠肝功能得到显著改善，外周血中TGF-β表达上调、IL-6的表达下调，肝组织中TGF-β和Foxp3、Smad3蛋白和mRNA均上调，而IL-6的mRNA表达下调。结论 樟芝多糖可以通过Treg和TGF-β-Smad3信号对NAFLD起到保护作用，作用机制和免疫改善有关。

Abstract:

OBJECTIVE To study the protective effect of polysaccharide from antrodia camphorata on nonalcoholic fatty liver disease (NAFLD) in mice by regulatory T-cell (Treg) controled. METHODS The model of NAFLD mice was established by high fat diet, and setted up the control group, model group, low dose group and high dose group. The proportion of Treg cells in peripheral blood were detected by flow cytometry and detect the expression of alanine aminotransferase (ALT), aspartate aminotransferase (AST), transforming growth factor beta (TGF-β) and interleukin-6 (IL-6) expression in 1-4 weeks. After 4 weeks, the mice were killed and the liver was stained with oil red staining. The expression of TGF-β, Foxp3 and Smad3 proteins in liver tissue were detected by Western blot. RT-qPCR was used to detect the mRNA expression of IL-6, TGF-b, Foxp3 and Smad3. RESULTS NAFLD mice model was successfully constructed after 4 weeks fed with high fat diet, and the proportion of Treg in model group was significantly lower than that in control group(P<0.05). Compared with the model group, the proportion of Treg increased significantly(P<0.05). The liver function of mice was significantly improved. The expression of TGF-β increased and IL-6 decreased in peripheral blood. The levels of TGF-β, Foxp3, Smad3 mRNA were up-regulated in liver tissues, whereas the expression of IL-6 mRNA was down. CONCLUSION The polysaccharide from antrodia camphorata can protect NAFLD via Treg and TGF-β-Smad3 signal pathway. The mechanism of action is related to immune improvement.