Department of Biophysics, University Hospital of Cerrahpasa, Istanbul, Turkey -
Department of Biophysics, University Hospital of Cerrahpasa, Istanbul, Turkey.
Minerva Endocrinol (Torino). 2021 Mar;46(1):107-115. doi: 10.23736/S2724-6507.20.03154-5.
Hypermetabolic state in hyperthyroidism causes oxidative stress. Erythrocytes are the cells that are involved in oxidant equilibrium in an organism and contain microRNA (miRNA). Selenium, which is an essential element for an organism, has antioxidant properties. The present study was aimed at investigating the effects of selenium supplementation in hyperthyroidism, on pro- and antioxidant enzymes, and miRNA (miR-144 and miR-451) expressions in the erythrocytes.
Forty-eight Sprague-Dawley male rats were divided into 6 groups; control group, group fed with 0.5 mg/kg sodium selenite; group fed with 1 mg/kg sodium selenite; hyperthyroid group; hyperthyroid group fed with 0.5 mg/kg sodium selenite; and hyperthyroid group fed with 1 mg/kg sodium selenite. Malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), miR-144, and miR-451 expression levels were studied in erythrocyte hemolysates.
MDA levels were increased in the hyperthyroid group compared to the control group, and the group fed with 0.5 mg/kg sodium selenite (P<0.001 and P<0.01, respectively). GSH levels were increased in the hyperthyroid group and the hyperthyroid group fed with 0.5 mg/kg sodium selenite compared to the control group (P<0.001, and P<0.05, respectively). GSH levels of the hyperthyroid group fed with 1 mg/kg sodium selenite were decreased when compared with the hyperthyroid group (P<0.05). SOD levels of the hyperthyroid group were increased when compared with the control group (P<0.05, and P<0.001, respectively). Similarly, SOD levels of the hyperthyroid group fed with 1 mg/kg sodium selenite were lower than the hyperthyroid group (P<0.01). miR-144 values were increased in the hyperthyroid group and the hyperthyroid group fed with 0.5 mg/kg sodium selenite compared to the control group (P<0.001, and P<0.05 respectively). miR-451 expression was increased significantly in the hyperthyroid group compared to the control group (P<0.05).
Our findings showed that MDA, SOD and GSH levels increased, and miR-144 and miR-451 expressions changed in hyperthyroidism. Supplementation of 1 mg/kg sodium selenite was more effective than 0.5 mg/kg sodium selenite for normalizing the MDA, GSH, SOD, and miRNA levels in the hyperthyroid group.
甲状腺功能亢进症中的高代谢状态会导致氧化应激。红细胞是参与机体氧化平衡的细胞，其中含有 microRNA（miRNA）。硒是生物体必需的元素，具有抗氧化特性。本研究旨在探讨在甲状腺功能亢进症中补充硒对红细胞中抗氧化酶和 miRNA（miR-144 和 miR-451）表达的影响。
将 48 只 Sprague-Dawley 雄性大鼠分为 6 组；对照组、给予 0.5mg/kg 亚硒酸钠的组、给予 1mg/kg 亚硒酸钠的组、甲状腺功能亢进组、给予 0.5mg/kg 亚硒酸钠的甲状腺功能亢进组和给予 1mg/kg 亚硒酸钠的甲状腺功能亢进组。研究了红细胞溶血物中的丙二醛（MDA）、超氧化物歧化酶（SOD）、谷胱甘肽（GSH）、miR-144 和 miR-451 的表达水平。
与对照组相比，甲状腺功能亢进组的 MDA 水平升高，给予 0.5mg/kg 亚硒酸钠的组（P<0.001 和 P<0.01）。与对照组相比，甲状腺功能亢进组和给予 0.5mg/kg 亚硒酸钠的甲状腺功能亢进组的 GSH 水平升高（P<0.001 和 P<0.05）。与甲状腺功能亢进组相比，给予 1mg/kg 亚硒酸钠的甲状腺功能亢进组的 GSH 水平降低（P<0.05）。与对照组相比，甲状腺功能亢进组的 SOD 水平升高（P<0.05，P<0.001）。同样，给予 1mg/kg 亚硒酸钠的甲状腺功能亢进组的 SOD 水平低于甲状腺功能亢进组（P<0.01）。与对照组相比，甲状腺功能亢进组和给予 0.5mg/kg 亚硒酸钠的甲状腺功能亢进组的 miR-144 值升高（P<0.001 和 P<0.05）。与对照组相比，甲状腺功能亢进组的 miR-451 表达显著升高（P<0.05）。
我们的研究结果表明，在甲状腺功能亢进症中，MDA、SOD 和 GSH 水平升高，miR-144 和 miR-451 的表达发生变化。与 0.5mg/kg 亚硒酸钠相比，补充 1mg/kg 亚硒酸钠对甲状腺功能亢进组 MDA、GSH、SOD 和 miRNA 水平的正常化更有效。
