探讨补脾强力复方干预亚甲减合并实验性自身免疫性重症肌无力大鼠下丘脑-垂体-甲状腺-胸腺轴功能损伤机制研究

Preliminary Study on the Intervention Mechanism of Bupi Qiangli Decoction(补脾强力复方)on HPTT Axis Functional Injury in Rats with Subclinical-hypothyroidism and EAMG

目的探讨补脾强力复方对亚甲减合并实验性自身免疫性重症肌无力(experimental autoimmune myasthenia gravis,EAMG)大鼠下丘脑-垂体-甲状腺-胸腺(HPTT)轴功能的修复作用,为补脾强力复方从神经-内分泌-免疫角度治疗重症肌无力及其共病寻找理论依据。方法实验通过甲巯咪唑灌胃45 d及含鼠源性AchR-sα亚基97-116肽段序列(R97-116)免疫乳剂皮下注射建立合并亚甲减的EAMG大鼠模型,随机分为模型组(M组)、泼尼松组(P组)、补脾强力复方低剂量组(LBD组)、补脾强力复方中剂量组(MBD组)、补脾强力复方高剂量组(HBD组),加上正常大鼠作为对照组(C组)。C组和M组灌胃等量0.9%氯化钠溶液,其余各组大鼠给予相应药物28 d,同时进行行为学观察后分别处死取血,通过酶联免疫吸附试验(ELISA)法检测大鼠血清AchR-Ab、促甲状腺激素(TSH)、促甲状腺激素释放激素(TRH)、三碘甲状腺原氨酸(T3)、甲状腺素(T4)、游离甲状腺素(fT4)含量及肿瘤坏死因子-α(TNF-α)、转化生长因子-β1(TGF-β1)、白细胞介素-4(IL-4)、白细胞介素-17(IL-17)相关细胞因子含量。结果建模后各组大鼠体质量相对C组明显下降(P<0.01),给药后取材前M组大鼠较各治疗组体质量明显下降(P<0.01);与LBD组相比,HBD组、P组大鼠体质量明显增加,差异具有统计学意义(P<0.01)。治疗后M组大鼠Lennon评分趋势进一步升高,LBD组、MBD组较给药前症状变化不明显,HBD组与P组Lennon评分降低。与M组相比,LBD组、MBD组、HBD组、P组大鼠血清AchR-Ab、TSH、TRH、TNF-α、IL-4、IL-17均下降,TGF-β均升高(P<0.05),其中以HBD组、P组变化更为明显(P<0.01),然而T3、T4、fT4变化不明显。结论补脾强力复方各组能一定程度上改善合并亚甲减的EAMG大鼠行为学异常,包括体质量和Lennon等级,其中高剂量组能够明显改善大鼠临床症状。同时补脾强力复方能够修复损伤的HPTT轴,调节该轴各个靶器官释放的激素水平,使其向正常机体的分泌水平靠近。

Objective To explorethe role of Bupi Qiangli Decoction(补脾强力复方)in repairing hypothalamic-pituitary-thyroid-thymus(HPTT)axis function in rats with subclinical-hypothyroidism and experimental autoimmune myasthenia gravis(EAMG),and finding the theoretical basis for the treatment of myasthenia gravis comorbidity with the Bupi Qiangli Decoction from the perspecitive of neuro-endocrine-immunology.Methods In terms of animal experiments,EAMG model rats with subclinical-hypothyroidism were successfully built by gavage of methimazole for 45 days and subcutaneous injection of immunoemulsion containing r97-116 peptide sequence of mouse AchR-Sαsubunit.Rats were randomly divided into model(M)group,prednisone(P)group,low dose of Bupi Qiangli Decoction(LBD)group,middle dose of Bupi Qiangli Decoction(MBD)group,high dose of Bupi Qiangli Decoction(HBD)group,plus normal rats as control(C)group,8 rats in each group.The rats in each group were given the corresponding drug for 28 days and then sacrificed after behavioral observation,and blood was collected to detect the contents of AchR-Ab,TSH,TRH,T3,T4,TNF-α,TGF-β1,IL-4 and IL-17 related cytokines in serum of rats with Enzyme-linked immunosorbent assay(ELISA).Results After modeling,compared with that in group C,the body weight of rats in each model group decreased with statistically significant difference(P<0.01);Before sampling,the body weight of rats in group M was significantly lower than that in all treatment groups(P<0.01).Compared with group LBD,the body weight of group HBD and group P increased with statistically significant difference(P<0.01).After treatment,the trend of Lennon score in group M increased further,while the changes of symptoms in the LBD and MBD groups were not significant,while the Lennon score in the HBD and P groups decreased.Compared with M group,serum AchR-Ab,TSH,TRH,TNF-α,IL-4 and IL-17 in LBD group,MBD group,HBD group and P group were decreased,while TGF-βwas increased(P<0.05),and the above changes were more obvious in HBD group and P group(P<0.01).However,the changes of T3,T4 and fT4 were not obvious.Conclusion The group of Bupi Qiangli Decoction could improve the behavioral abnormalities of EAMG rats with subclinical-hypothyroidism to a certain extent,including body weight and Lennon grade,especially the high dose group.Bupi Qiangli Decoction can repair the damaged HPTT axis,regulate the hormone level released by each target organ of the axis,so that it is close to the secretion level of the normal body.