METHODS: An experimental autoimmune thyroiditis (EAT) mouse model was established with a high-iodine diet. After 8 weeks, thyroid injury was assessed using hematoxylin and eosin (H&E) staining. ELISA was employed to measure serum levels of thyroxine (T3 and T4), thyroid autoimmune antibodies (Tg-Ab and TPO-Ab), and inflammatory cytokines. Flow cytometry and multiplex fluorescence immunohistochemical (mIHC) assays were used to analyze Th17/Treg cell subsets. The CCK-8 and flow cytometry assays were used to determine cell viability and apoptosis.
RESULTS: Administration of VitD3 reduced thyroid follicle destruction, decreased lymphocyte infiltration, and lowered T3, T4, Tg-Ab, and TPO-Ab serum levels in EAT mice. VitD3 treatment also reduced the frequency of Th17 cells while promoting the Treg cell subset both in the thyroid tissue and in the splenocytes cultured in vitro. Furthermore, VitD3 administration suppressed the production of inflammatory cytokines in EAT mice. VitD3 was also found to regulate Treg cells\' differentiation, viability, and apoptosis. Mechanistically, we discovered that VitD3 treatment upregulated YAP expression and activated the JAK/STAT pathway. Rescue assays confirmed that depletion of YAP counteracted the effects of VitD3 on Treg cell differentiation and function.
CONCLUSIONS: Vitamin D3 attenuates AITD by modulating Th17/Treg cell balance via regulating the YAP/JAK1/STAT1 axis.
方法:采用高碘饮食建立实验性自身免疫性甲状腺炎(EAT)小鼠模型。8周后,使用苏木精和伊红(H&E)染色评估甲状腺损伤.ELISA检测血清甲状腺素水平(T3和T4),甲状腺自身免疫抗体(Tg-Ab和TPO-Ab),和炎性细胞因子。流式细胞术和多重荧光免疫组织化学(mIHC)测定用于分析Th17/Treg细胞亚群。CCK-8和流式细胞术测定用于确定细胞活力和凋亡。
结果:服用VitD3可减少甲状腺滤泡破坏,淋巴细胞浸润减少,降低T3,T4,Tg-Ab,和EAT小鼠的TPO-Ab血清水平。VitD3处理还降低了Thl7细胞的频率,同时促进了体外培养的甲状腺组织和脾细胞中的Treg细胞亚群。此外,VitD3给药抑制了EAT小鼠中炎性细胞因子的产生。还发现VitD3调节Treg细胞的分化,生存能力,和凋亡。机械上,我们发现VitD3治疗上调YAP表达并激活JAK/STAT通路.挽救试验证实YAP的消耗抵消了VitD3对Treg细胞分化和功能的影响。
结论:维生素D3通过调节YAP/JAK1/STAT1轴来调节Th17/Treg细胞平衡,从而减轻AITD。