Department of Endocrinology and Metabolism, Institute of Endocrinology, First Affiliated Hospital, China Medical University, Shenyang, China.
Endocr J. 2010;57(7):595-601. doi: 10.1507/endocrj.k10e-063. Epub 2010 Apr 27.
Selenium (Se) is required for thyroid hormone synthesis and metabolism. Se treatment reduces serum thyroidspecific antibody titers in patients with autoimmune thyroiditis (AIT), but the exact mechanism is not clear. We investigated the effects of Se treatment on CD4(+)CD25(+)Foxp3(+) regulatory T cells (Treg) in a iodine-induced autoimmune thyroiditis model. NOD.H-2(h4) mice were randomly divided into control, AIT untreated, and AIT with Se treatment groups. Mice were fed with 0.005% sodium iodine (NaI) water for 8 weeks to induce AIT. Se-treated mice received 0.3 mg/L sodium selenite in drinking water. The AIT mice had fewer Treg cells and reduced Foxp3 mRNA expression in splenocytes compared with the controls (p < 0.01). The percentage of Treg cells and expression of Foxp3 mRNA were increased by Se treatment (as compared with untreated AIT mice, p < 0.05). Mice that received Se supplementation also had lower serum thyroglobulin antibody (TgAb) titers and reduced lymphocytic infiltration in thyroids than untreated AIT mice. These data suggest that CD4(+)CD25(+) T cells play an important role in the development of AIT. Se supplementation may restore normal levels of CD4(+)CD25(+) T cells by up-regulating the expression of Foxp3 mRNA in mice with AIT.
硒（Se）是甲状腺激素合成和代谢所必需的。硒治疗可降低自身免疫性甲状腺炎（AIT）患者的血清甲状腺特异性抗体滴度，但确切机制尚不清楚。我们研究了硒治疗对碘诱导的自身免疫性甲状腺炎模型中 CD4+CD25+Foxp3+调节性 T 细胞（Treg）的影响。NOD.H-2（h4）小鼠随机分为对照组、AIT 未治疗组和 AIT 加硒治疗组。用 0.005%碘化钠（NaI）水喂养小鼠 8 周以诱导 AIT。硒治疗组小鼠饮用含 0.3mg/L 亚硒酸钠的水。与对照组相比，AIT 小鼠的 Treg 细胞较少，脾细胞中 Foxp3 mRNA 表达降低（p<0.01）。硒治疗增加了 Treg 细胞的比例和 Foxp3 mRNA 的表达（与未治疗的 AIT 小鼠相比，p<0.05）。接受硒补充的小鼠的血清甲状腺球蛋白抗体（TgAb）滴度也较低，甲状腺中的淋巴细胞浸润减少。这些数据表明 CD4+CD25+T 细胞在 AIT 的发展中起重要作用。硒补充可能通过上调 AIT 小鼠 Foxp3 mRNA 的表达来恢复 CD4+CD25+T 细胞的正常水平。
