茶多酚对兔动脉粥样斑块中免疫因素的影响

Effect of tea polyphenols on the immune factors in the atherosclerotic plaque lesion in rabbits

目的:通过建立动脉粥样硬化(Atherosclerosis,AS)兔模型探讨茶多酚(Tea polyphenols,TP)具有的免疫调节作用对动脉粥样斑块中IgG、IgM型免疫复合物(Immune complex,IC)、巨噬细胞(Microphage,M(?))等免疫因素的影响。方法:将40只纯种新西兰大白兔随机分为正常对照组(NC)、动脉粥样硬化模型对照组(ASC)、低剂量TP组(LTP)、高剂量TP组(HTP)及辛伐他汀组(Sim),共喂养12周。苏木精伊红(HE)染色、免疫组化染色分析AS斑块病变程度、IgG及IgM型IC的沉积、M(?)的浸润,以及TP干预对此过程的影响。结果:模型在高脂饲料喂养12周后形成明显的AS斑块,IgG型IC在斑块中大量沉积,主要沉积在斑块的脂质核心及斑块肩部,而IgM型IC在斑块中沉积不明显,M(?)在斑块内亦大量浸润。IgG及M(?)的表达在ASC组明显高于其他组(P<0.05),高、低剂量TP能抑制IgG及M(?)在斑块内表达,高剂量TP较低剂量TP抑制程度更大(P<0.05),与辛伐他汀的抑制程度相似。结论:AS斑块内存在以IgG为主的IC,它与AS的发生发展密切相关,茶多酚能通过其免疫调节作用抑制IC及M(?)在斑块内的表达,并具有一定的量效关系。

Objective：To evaluate the effect on immunomodulation of tea polyphenols（TP）, and to study the influence of tea polyphenols on the immune factor in the atherosclerotic plaque lesion in rabbits. Methods ： Forty male true-bred New Zealand rabbits were randomly divided into five groups： normal control group（ NC ）, atherosclerosis model control group （ASC）, low dose of TP group （LTP）, high dose of TP group （HTP） and simvastatin group （Sire）. The structural change of artery, the deposit of IgG and IgM and the infiltration of macrophage in plaque lesions of AS were analyzed by hematoxylin and eosin staining and immunohistochemistry. Results ： Plaque lesions of AS were obvious after 12-week high-cholestrol feeding. The IC of IgG accumulated in plaque lesions, while the IC of IgM was not detected. The IC of IgG mainly localized in the core and the shoulder of mature plaque lesions and macrophage were greatly infiltrated in the plaque lesions. In comparison with other groups, the expression of IgG and macrophage in the plaque lesions were stronger in atherosclerosis model group（P〈0.05 ）. High and low dose of TP could depress the expression of IgG and macrophage in the plaque lesions. The depressing amplitude in HTP group was more than that in LTP group（P〈0.05 ）, but there was no difference between HTP group and Sire group. Conclusion： The IC of IgG and the macrophage exist in the plaque lesions of AS. The IC and the macrophage are closely related to the origin and progress of AS. The tea polyphenols can inhibit the formation of IC and depress the expression of macrophage in the plaque lesions through its effect on immunomodulation, and to some degree, the effect has dose-effect relationship.