Protective effect of thyroid and restores of ovarian function of Buzhong Yiqi granule on experimental autoimmune thyroiditis in female rats.

OBJECTIVE: To observe the effects of Buzhong Yiqi granule on thyroid function and ovarian function in rats with experimental autoimmune thyroiditis (EAT).

METHODS: EAT model was replicate by using the method of mixing and injecting porcine thyroglobulin with Freund's adjuvant and high iodine. Rats were randomly divided into normal control (NC) group, EAT model (EAT) group, selenium yeast (PC) group, low dose Buzhong Yiqi (BZYQ-L) group, medium dose Buzhong Yiqi (BZYQ-M) group and high dose Buzhong Yiqi (BZYQ-H) group. After two months of drug intervention according to dosage, enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), anti-thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TGAb) in peripheral blood of rats. The pathological changes of rat thyroid tissues were observed under light microscope with HE staining; ELISA was used to determine estradiol (E2), follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone (T), anti-müllerian hormone (AMH), and the pathological changes of rat ovarian tissues were observed under light microscope with hematoxylin and eosin staining.

RESULTS: Compared with the NC group, BZYQ granule improved the thyroid and ovarian tissue morphology, and the levels of TPOAb, TGAb and TSH in the model group rats significantly increased ( P < 0.05), the thyroid tissue was severely destroyed, the levels of E2, FSH, LH, T, AMH significantly increased ( P < 0.05), and the ovary exhibited polycystic changes; Compared with the model group, TSH level in the BZYQ-L group rats decreased ( P < 0.05), FSH, T, AMH levels decreased ( P < 0.05), in the BZYQ-M group TPOAb, TSH levels decreased ( P < 0.05), FSH, LH, T, AMH levels significantly decreased ( P < 0.05), BZYQ-H group TPOAb, TGAb, TSH levels significantly decreased ( P < 0.05), FSH, LH, T, AMH levels significantly decreased ( P < 0.05), with the greatest improvement and significantly better than selenium yeast group ( P < 0.05).

CONCLUSIONS: BZYQ granule could regulate the thyroid function of EAT rats, reduce thyroid antibody titers, then act on the ovarian function, regulate hormone disorders, and alleviate the pathological damage of rat's ovarian tissues. The effect of high dose Buzhong Yiqi granule is the best.