Health Research Institute, Diabetes Research Center, Department of Physiology, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
Department of Pharmacology, School of Medicine, Student Research Committee of Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
Biol Trace Elem Res. 2018 Mar;182(1):37-48. doi: 10.1007/s12011-017-1068-1. Epub 2017 Jun 8.
The thyroid is one of the major endocrine glands that contribute to body and fat metabolism. The present study evaluated the effects of combined exposure to chronic high-fat diet (HFD) and arsenic on thyroid function and lipid profile. In this experimental study, 72 male Naval Medical Research Institute mice were divided into six groups and fed HFD or low-fat diet (LFD) while being exposed to 25 or 50 ppm of arsenic in drinking water for 20 weeks. After 24 h of the last experimental day, blood samples were collected for hormonal and biochemical measurements. The data indicated that exposure to HFD alone increased the levels of triiodothyronine (T3), thyroid-stimulating hormone (TSH), leptin, lipid profile, reactive oxygen species (ROS), and malondialdehyde (MDA) and decreased the levels of high-density lipoprotein, albumin, adiponectin, and glutathione sulfhydryl reductase (GSH), whereas exposure to arsenic alone decreased the levels of T3 and GSH and increased the levels of TSH, leptin, ROS, MDA, and T4/T3 ratio compared to those in the control LFD group. Furthermore, concomitant administration of HFD and arsenic decreased the lipid profile and levels of T4, albumin, total protein, T3, and GSH and increased the levels of TSH, adiponectin, leptin, ROS, MDA, and T4/T3 ratio compared to those in the control LFD or HFD group. In conclusion, combined exposure to HFD and arsenic induced hypothyroidism via reduction of thyroid hormones and enhancement of plasma TSH and T3 uptake levels concomitant with hypolipidemia, hyperleptinemia, hyperadiponectinemia, induction of oxidative stress, and reduction of GSH levels.
甲状腺是参与身体和脂肪代谢的主要内分泌腺之一。本研究评估了慢性高脂肪饮食（HFD）和砷联合暴露对甲状腺功能和血脂谱的影响。在这项实验研究中，72 只雄性海军医学研究所小鼠被分为六组，分别用 HFD 或低脂饮食（LFD）喂养，并在饮用水中暴露于 25 或 50 ppm 的砷 20 周。在最后一个实验日的 24 小时后，采集血液样本进行激素和生化测量。数据表明，单独暴露于 HFD 会增加三碘甲状腺原氨酸（T3）、促甲状腺激素（TSH）、瘦素、血脂谱、活性氧（ROS）和丙二醛（MDA）的水平，降低高密度脂蛋白、白蛋白、脂联素和谷胱甘肽巯基还原酶（GSH）的水平，而单独暴露于砷会降低 T3 和 GSH 的水平，并增加 TSH、瘦素、ROS、MDA 和 T4/T3 比值，与 LFD 对照组相比。此外，同时给予 HFD 和砷会降低血脂谱和 T4、白蛋白、总蛋白、T3 和 GSH 的水平，并增加 TSH、脂联素、瘦素、ROS、MDA 和 T4/T3 比值，与 LFD 或 HFD 对照组相比。总之，HFD 和砷的联合暴露通过降低甲状腺激素和增强血浆 TSH 和 T3 摄取水平，同时伴有血脂降低、瘦素血症、脂联素血症、氧化应激诱导和 GSH 水平降低，导致甲状腺功能减退。
