补中益气汤对自身免疫性甲状腺炎模型大鼠甲状腺抗体及Th相关细胞因子的影响

Effects of Buzhong Yiqi Tang on thyroid antibodies and Th-related cytokines in autoimmune thyroiditis model rats

目的观察补中益气汤对实验性自身免疫性甲状腺炎(EAT)模型大鼠甲状腺抗体、Th相关细胞因子和甲状腺组织病理形态的影响。方法运用猪甲状腺球蛋白和弗氏佐剂混合免疫注射法,联合高碘喂养法复制EAT大鼠模型,将36只SD大鼠随机分为模型组、硒酵母组、补中益气汤组、空白组,每组9只。硒酵母组灌胃西药硒酵母(20.67μg/kg),补中益气汤组灌胃补中益气颗粒(0.93 g/kg),空白组和模型组灌胃等体积的动物饮用水。灌胃干预56 d后,采用酶联免疫吸附(ELISA)法测定大鼠外周血游离三碘甲状腺原氨酸(FT3)、游离甲状腺素(FT4)、三碘甲状腺原氨酸(T3)、甲状腺素(T4)、血清促甲状腺素(TSH)、甲状腺过氧化物酶抗体(TPOAb)、甲状腺球蛋白抗体(TGAb)、白细胞介素-4(IL-4)、白细胞介素-38(IL-38)、γ干扰素(IFN-γ)水平,HE染色法光镜下观察大鼠甲状腺组织病理改变。结果与空白组比较,模型组大鼠FT3、FT4、T3、T4、TSH、TPOAb、TGAb、IFN-γ、IFN-γ/IL-4水平升高(P<0.05),IL-4、IL-38水平下降(P<0.05),甲状腺组织中大量淋巴细胞浸润;与模型组比较,补中益气汤组和硒酵母组FT3、FT4、T3、T4、TGAb、TPOAb、IFN-γ、IFN-γ/IL-4水平下降(P<0.05),IL-4、IL-38水平升高(P<0.05);补中益气汤组与硒酵母组比较TGAb、TPOAb水平下降(P<0.05)。各给药组大鼠甲状腺组织淋巴细胞的浸润程度较模型组明显减轻,淋巴细胞浸润改善程度补中益气汤组优于硒酵母组。结论补中益气汤通过调节甲状腺自身免疫功能,改善EAT大鼠甲状腺功能,降低TGAb、TPOAb水平,减轻甲状腺组织淋巴细胞的浸润;硒酵母和补中益气汤均能通过调节Th1/Th2平衡与IL-38水平来改善EAT,补中益气汤效果略优于硒酵母。

Objective To observe the effects of Buzhong Yiqi Tang(Center-supplementing and Qi-boosting Decoction,BZYQT)on thyroid antibody,Th-related cytokines and histopathological morphology of experimental autoimmune thyroiditis(EAT)model rats.Methods The EAT rat model was replicated using a mixed immunoinjection method of pig thyroglobulin and Fredrin’s adjuvant combined with high iodine feeding method,and the rats were randomly divided into the model group,selenium yeast group,BZYQT group,and blank group,with nine rats in each group.Selenium yeast group was given selenium yeast(20.67μg/kg),while BZYQT group was given Buzhong Yiqi Granules(0.93 g/kg),and the blank and model groups were given equal volums of drinking water.After 56 days of the intervention,free triiodothyronine(FT3),free thyroxine(FT4),triiodothyronine(T3),thyroxine(T4),thyroid-stimulating hormone(TSH),thyroperoxidase antibody(TPOAb),thyroglobulin antibody(TGAb),interleukin-4(IL-4),interleukin-38(IL-38),interferon-γ(IFN-γ)were detected in the peripheral blood of rats by enzyme-linked immunosorbent(ELISA)determination,and the histopathological changes of rat thyroid were observed under light microscope by HE staining.Results Compared with the blank group,FT3,FT4,T3,T4,TPOAb,TGAb,IFN-γand IFN-γ/IL-4 increased(P<0.05),while IL-4 and IL-38 decreased(P<0.05),and a large number of lymphocytes were infiltrated in thyroid tissue in the model group.Compared with the model group,FT3,FT4,T3,T4,TGAb,TPOAb,IFN-γand IFN-γ/IL-4 in BZYQT group and selenium yeast group decreased(P<0.05),while IL-4 and IL-38 increased(P<0.05).Compared with selenium yeast group,TGAb and TPOAb in BZYQT group decreased(P<0.05).Under light microscope,the degree of lymphocyte infiltration in the thyroid tissue of rats in the two groups significantly reduced compared with that in the model group,and the improvement of infiltration in the BZYQT group was better than that in the selenium yeast group.Conclusion BZYQT can improve the thyroid function of EAT rats by regulating the autoimmune function,reduce the levels of TGAb and TPOAb,and alleviate the lymphocyte infiltration in thyroid tissues.Both selenium yeast and BZYQD can improve EAT by regulating Th1/Th2 balance and IL-38 level,and the effect of BZYQD is slightly better than that of selenium yeast.