Muazzez Alireza, Shimi Ghazaleh, Balam Farinaz H, Ghorbani Arman, Zand Hamid
Department of Cellular and Molecular Nutrition, Faculty of Nutrition Science and Food Technology, National Nutrition and Food Technology Research Institute, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Indian J Endocrinol Metab. 2024 May-Jun;28(3):320-326. doi: 10.4103/ijem.ijem_400_23. Epub 2024 Jun 26.
Energy status can alter thyroid hormone signalling in different tissues. Little is known about the effect of fasting on the local thyroid hormone metabolism under high-fat diet (HFD)-induced obesity. We aimed to investigate the fasting effect on deiodinase type 3 (DIO3) and thyroid hormone receptors (TRs) expression in liver and visceral adipose tissue (VAT) of HFD-induced obese mice.
The 30 male C57BL/6 mice were divided into three groups ( = 10/group): control (CON) group, obese (OB) group, and fasted obese (OBF) group.
In a 14-week study, the expression levels of DIO3 and TRs in the liver and VAT of mice were measured by real-time polymerase chain reaction. Gene expression results were shown as fold changes defined by 2 Comparison between groups was performed by using one-way-ANOVA or Kruskal-Wallis ANOVA test.
In the liver, there was a significantly lower expression of DIO3 and higher expression of TRs in obese fasted mice compared to obese mice. Compared to the lean mice, OBF mice had significantly lower expression of DIO3 and higher expression of TRβ. In the VAT, mRNA expression of DIO3 was significantly increased in OBF and OB groups compared to the CON group. There were no significant differences in the mRNA expression of TRs between groups.
Our findings suggest that fasting may be more effective in improving thyroid hormone metabolism in the liver rather than the VAT of obese mice.
能量状态可改变不同组织中的甲状腺激素信号传导。关于禁食对高脂饮食（HFD）诱导的肥胖状态下局部甲状腺激素代谢的影响，目前所知甚少。我们旨在研究禁食对HFD诱导的肥胖小鼠肝脏和内脏脂肪组织（VAT）中3型脱碘酶（DIO3）和甲状腺激素受体（TRs）表达的影响。
将30只雄性C57BL/6小鼠分为三组（每组n = 10）：对照组（CON）、肥胖组（OB）和禁食肥胖组（OBF）。
在一项为期14周的研究中，通过实时聚合酶链反应测量小鼠肝脏和VAT中DIO3和TRs的表达水平。基因表达结果以2-ΔΔCt定义的倍数变化表示。组间比较采用单因素方差分析或Kruskal-Wallis方差分析检验。
在肝脏中，与肥胖小鼠相比，肥胖禁食小鼠的DIO3表达显著降低，TRs表达升高。与瘦小鼠相比，OBF小鼠的DIO3表达显著降低，TRβ表达升高。在VAT中，与CON组相比，OBF组和OB组的DIO3 mRNA表达显著增加。各组之间TRs的mRNA表达没有显著差异。
我们的研究结果表明，禁食可能对改善肥胖小鼠肝脏而非VAT中的甲状腺激素代谢更有效。
