Effect of Zuojin Pill on HIF-1α expression and apoptosis of thyroid cells in rats with autoimmune thyroiditis / 国际中医中药杂志

ABSTRACT

Objective:To investigate the effect of Zuojin Pill on the expression of hypoxia inducible factor-1α (HIF-1α) and apoptosis of thyroid cells in rats with autoimmune thyroiditis (AIT). Methods:Ninetysix rats were divided into control group, model group, standarlized protocol and low, medium and high dose Zuojin Pill groups. Except the control group, the rats in other groups were produced as AIT model. After successful modeling, rats in low-, medium-, and high-dose groups were intragastrically administered with 0.63, 1.26, and 2.52 g/kg Zuojin Pill respectively, standarlized protocol was given 6.25 mg/kg Tripterygium wilfordii polyglycoside, and the control group and model group were given the same amount of normal saline. The levels of tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10), thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TGAb) were detected by enzyme-linked immunosorbent assay (ELISA); the activity of SOD and the content of MDA in thyroid tissue were detected by kit; the pathological changes of thyroid tissue were observed by HE staining; the apoptosis of thyroid cells was detected by TUNEL; the expression of HIF-1α, B-cell lymphoma-2 (Bcl-2), Bcl-2-related X protein (Bax) and Cleaved caspase-3 in thyroid tissues was detected by Western blot. Results:Compared with the model group, the content of TNF-α, TPOAb and TGAb in serum of rats in the low, medium and high dose Zuojin Pill groups significantly decreased, the content of IL-10 in serum significantly increased ( P<0.05). The SOD activity significantly increased, and the MDA content significantly decreased in the low, medium and high dose Zuojin Pill groups ( P<0.05). The apoptosis rate significantly decreased in the low, medium and high dose Zuojin Pill groups ( P<0.05). The expression of HIF-1α (0.48 ± 0.05, 0.63 ± 0.06, 0.86 ± 0.06 vs. 0.33 ± 0.03), Bcl-2 (0.48 ± 0.04, 0.59 ± 0.05, 0.68 ± 0.04 vs. 0.37 ± 0.04) significantly increased, the expression of Bax (0.67 ± 0.05, 0.53 ± 0.05, 0.40 ± 0.05 vs. 0.80 ± 0.06), Cleaved caspase-3 (0.64 ± 0.06, 0.51 ± 0.03, 0.36 ± 0.03 vs. 0.77 ± 0.05) significantly decreased in the low, medium and high dose Zuojin Pill groups ( P<0.05). Conclusion:Zuojin Pill could enhance the expression of HIF-1α, regulate the secretion of inflammatory factors, reduce the level of oxidative stress and thyroid autoantibody, and inhibit the apoptosis of thyroid cells.