Study on effect of astragaloside Ⅳ on apoptosis of thyroid cells in rats with Hashimoto's thyroiditis and RhoA/ROCK2 pathway / 中国免疫学杂志

ABSTRACT

Objective:To investigate the effect of astragaloside Ⅳ on the apoptosis of thyroid cells in Hashimoto's thyroiditis(HT)rats and Ras homolog gene family member A(RhoA)/Rho-associated coiled-coil containing kinase 2(ROCK2)pathway.Methods:The HT rat model was induced by subcutaneous injection of thyroglobulin combined with high iodine drinking water and randomly divided into model group,astragaloside(80 mg/kg)group,Rhosin(RhoA inhibitor,40 mg/kg)group,astragaloside Ⅳ(80 mg/kg)+ Rhosin(40 mg/kg)group(12 rats in each group),another 12 SD rats were selected and drank water normally and injected the same dose of saline subcutaneously as control group.After the drugs were grouped and processed,the serum anti-thyroglobulin antibody(TGAb),anti-thyroid peroxidase antibody(TPOAb)levels and the inflammatory factors IL-6,IL-17,IL-1β contents were measured by ELISA kits;the pathological changes of thyroid tissue in each group were detected by hematoxylin-eosin(HE)staining;the apopto-sis rate of rat thyroid cells in each group were detected by TUNEL staining;the expressions of RhoA/ROCK2 pathway proteins in thy-roid tissues of rats in each group were detected by Western blot.Results:Compared with the control group,the thyroid follicles in the model group had abnormal structure,some atrophy or disappearance,disordered arrangement,surrounding inflammatory cell infiltra-tion,and obvious pathological damage to the thyroid tissue,the serum TGAb,TPOAb,IL-6,IL-17 and IL-1β levels,thyroid cell apoptosis rate,and thyroid tissue RhoA and ROCK2 protein expression levels were significantly increased(P<0.05);compared with model group,the pathological damage of the thyroid tissue of rats in the drug intervention group were reduced,the serum TGAb,TPOAb,IL-6,IL-17 and IL-1β levels,thyroid cell apoptosis rate,and thyroid tissue RhoA and ROCK2 protein expression levels were decreased(P<0.05);compared with astragaloside Ⅳ group and the Rhosin group respectively,the pathological damage of the thyroid tissue of rats in the astragaloside Ⅳ+Rhosin group were further reduced,the serum TGAb,TPOAb,IL-6,IL-17 and IL-1β levels,thyroid cell apoptosis rate,thyroid tissue RhoA and ROCK2 protein expression levels were decreased(P<0.05).Conclusion:Astragaloside Ⅳ may down-regulate the expression of RhoA/ROCK2 pathway to reduce the inflammatory injury of thyroid tissue,inhib-it thyroid cell apoptosis,and improve the symptoms of HT in rats.