基于NLRP3/Caspase-1信号通路探讨异甘草素对自身免疫性甲状腺炎小鼠的保护作用

Protective effect of isoliquiritigenin on autoimmune thyroiditis in mice based on NLRP3/Caspase-1 signaling pathway

关键词:  异甘草素  自身免疫性甲状腺炎  雷公藤多苷片  小鼠

Key words:  isoliquiritigenin  autoimmune thyroiditis  tripterygium wilfordii polyglycoside tablet  mouse

摘要:

[目的] 基于NLRP3/Caspase-1信号通路探讨异甘草素对自身免疫性甲状腺炎(AIT)小鼠的保护作用。[方法] 60只SPF级C57BL/6J小鼠随机分为空白对照组、模型组、雷公藤多苷片组以及异甘草素高中低剂量组,每组10只。通过皮下注射高碘水和猪甲状腺球蛋白混合液建立AIT小鼠模型。于造模当天给药组小鼠采用灌胃给药干预2周。实验结束后,分别检测各组小鼠血清自身免疫相关抗体[甲状腺过氧化物酶抗体(TPOAb)和甲状腺球蛋白抗体(TGAb)]和炎症因子[白细胞介素(IL)-8、IL-6和IL-23]的水平;采用HE染色法观察各组小鼠甲状腺组织的病理学情况;使用Western blot法检测各组小鼠甲状腺组织NLRP3和Caspase-1蛋白的表达水平。[结果] 与空白对照小鼠比较,模型组小鼠的血清自身免疫相关抗体(TPOAb和TGAb)和炎症因子(IL-8、IL-6和IL-23)水平显著升高(P<0.01)。此外,模型组小鼠甲状腺组织中炎症细胞浸润明显,甲状腺组织NLRP3和Caspase-1蛋白表达水平明显上调(P<0.01),提示AIT小鼠模型构建成功。与模型组比较,各给药组均明显降低血清自身免疫相关抗体(TPOAb和TGAb)和炎症因子(IL-8、IL-6和IL-23)水平(P<0.05),甲状腺组织中炎症细胞的浸润程度显著减轻,甲状腺组织NLRP3和Caspase-1蛋白的表达水平明显下调(P<0.05),其中异甘草素给药组改善小鼠AIT呈浓度依赖性。[结论] 异甘草素可能通过调控NLRP3/Caspase-1信号通路以及抑制炎症,从而改善AIT小鼠的系列症状。

Abstract:

[Objective] To observe the protective effect of isoliquiritigenin on autoimmune thyroiditis(AIT) in mice based on nucleotide-binding oligomerization domain,leucine-rich repeat and pyrin domain-containing 3(NLRP3)/Caspase-1 signaling pathway. [Methods] Sixty Specific Pathogen Free(SPF) C57BL/6J mice were randomly divided into blank control group,model group,tripterygium wilfordii polyglycoside tablet group and isoliquiritigenin high and low dose group,with 10 mice in each group. The mouse model of AIT was established by subcutaneous injection of high iodine water and pig thyroglobulin mixture. On the day of modeling,the mice in the administration group were given oral administration for 2 weeks. After the experiment,the serum levels of autoimmune antibodies including antithyroid peroxidase autoantibody(TPOAb) and anti-thyroglobulin antibodies(TGAb) and inflammatory factors including interleukin-8(IL-8),interleukin-6(IL-6) and Interleukin-23(IL-23) were detected. HE staining was used to observe the pathological changes of thyroid tissue in each group of mice. Western blot was used to detect the expression levels of NLRP3 and Caspase-1 protein in thyroid tissue of mice in each group. [Results] Compared with the blank control mice,the levels of serum autoimmune-related antibodies(TPOAb and TGAb) and inflammatory factors(IL-8,IL-6 and IL-23) in the model group were significantly higher(P<0.01). In addition,inflammatory cells infiltrated obviously in the thyroid tissue of the model group,and the expression levels of NLRP3 and Caspase-1 protein in the thyroid tissue were significantly increased(P<0.01),suggesting that the mouse model of AIT was successfully established. Compared with the model group,the levels of serum autoimmune-related antibodies(TPOAb and TGAb) and inflammatory factors(IL-8,IL-6 and IL-23) were significantly decreased in all groups(P<0.05),the infiltration of inflammatory cells in thyroid tissue was significantly reduced,and the expression levels of NLRP3 and Caspase-1 protein in thyroid tissue were significantly decreased(P<0.05). In the isoliquiritigenin group,AIT was improved in a concentration-dependent manner. [Conclusion] Isoliquiritigenin may improve the symptoms of AIT mice by regulating NLRP3/Caspase-1 signaling pathway and inhibiting inflammation.