Aa-LPS诱导下兔肝巨噬细胞膜表面受体及氧化应激反应的影响

Effects of Aa-LPS on the expression of membrane surface rece-ptors and oxidative stress response of hepatic macrophage

目的探讨伴放线聚集杆菌-脂多糖(Aa-LPS)对不同血脂状态下肝巨噬细胞免疫反应的影响及可能的作用机制。方法高脂新西兰兔建模成功后,分离纯化高脂和普通饮食组肝巨噬细胞,加入Aa-LPS刺激培养24 h,检测肝巨噬细胞膜受体CD14、TLR4、TLR2、SR-A和MHC-ⅡmRNA表达的变化和活性氧水平以及NO释放量。结果Aa-LPS刺激24 h后,高脂组CD14、TLR2、TLR4、SRA和MHC-ⅡmRNA表达量升高(P<0.05),普通饮食组TLR4 mRNA降低(P<0.05)。Aa-LPS、大肠杆菌-LPS刺激后2组兔肝巨噬细胞的活性氧和NO释放增加,且高脂组活性氧和NO释放量显著高于普通饮食组(P<0.05)。不同血脂状态下,大肠杆菌-LPS组NO、活性氧释放量均显著低于Aa-LPS组(P<0.05)。结论高脂饮食影响肝巨噬细胞的氧化还原状态,在牙周常见致病菌Aa-LPS诱导下2组参与信号启动的模式识别受体激活途径不一致,高脂状态下发生更高的氧化应激反应,且可能与TLR2/4相关。

Objective Explore the effect of Actinobacillus actinomycetemcomitans-lipopolysaccharide(Aa-LPS)on the immune reaction of hepatic macrophages under different blood lipid states and its possible mecha-nism.Methods After a successful modeling of high-fat New Zealand rabbits,macrophage in the high-fat diet(HFD)and the normal diet(RD)groups were isolated and purified,and stimulated by Aa-LPS for 24 h;the mRNA expression of macrophage membrane receptors CD14,TLR2,TLR4,SR-A and MHC-,and reactive oxygen species(ROS)level,and nitric oxide(NO)release were detected.Results After the 24 h stimulation with Aa-LPS,the expression of membrane surface receptors of macrophage the CD14,TLR2,TLR4,SRA and MHC-mRNA in the HFD group was raised(P<0.05),while TLR4 mRNA decreased in the RD group(P<0.05).The release of ROS and NO increased after a stimulation with Aa-LPS and Escherichia coli-LPS,and the release of ROS and NO in the HFD group was significantly higher than that in the RD group(P<0.05).Under different blood lipid status,the release of NO and ROS in the Escherichia coli-LPS group was significantly lower than that in the Aa-LPS group(P<0.05).Conclusion HFD can affect the redox state of liver macrophages.Under the induction of common periodontal pathogen Aa-LPS,the activation pathway of pattern recognition receptors involved in signal initiation in the two groups is inconsistent,and a higher oxidative stress reaction occurs in a high fat state,and probably related to TLR 2/4.