TRIM32通过控制肝脏胰岛素受体降解来调节胰岛素敏感性
Shilpa Thakur1, Priya Rawat1, Budheswar Dehury2
1School of Biosciences and Bioengineering, Indian Institute of Technology Mandi, Mandi, 175005, H.P., India.
EMBO reports
|January 3, 2025
概括
三方基因含蛋白32 (TRIM32) 通过降低肝脏中的胰岛素受体 (INSR) 来驱动与肥胖相关的胰岛素耐药性. 在高脂肪饮食模型中,减少TRIM32可以改善胰岛素敏感性和肝脏健康.
科学领域:
- 代谢性疾病研究研究.
- 分子生物学分子生物学
- 肝病学 肝病学是一种肝病学.
背景情况:
- 胰岛素受体 (INSR) 信号受损导致与肥胖相关的疾病,如非酒精性脂肪肝疾病 (NAFLD) 和2型糖尿病 (T2DM).
- 在饮食引起的肥胖中,肝脏胰岛素抵抗的确切分子机制尚未完全理解.
研究的目的:
- 在高脂肪饮食 (HFD) 诱导的肥胖中确定肝脏胰岛素信号的关键调节者.
- 为了阐明三方基因含蛋白32 (TRIM32) 在饮食诱导的肝脏胰岛素耐药性中的作用.
主要方法:
- 使用高脂肪饮食 (HFD) 诱导肥胖 (DIO) 的小鼠模型.
- 研究了TRIM32在肝细胞中的表达和功能.
- 分析了胰岛素受体 (INSR) 无化和蛋白质体降解.
- 进行了肝脏特异性TRIM32敲击实验.
- 评估肝脏胰岛素敏感性和脂质积累.
主要成果:
- 高脂肪饮食 (HFD) 增加了SREBP-1c的核转移,提高了肝脏TRIM32表达的调节.
- TRIM32针对胰岛素受体 (INSR) 进行全方位化和蛋白质体降解.
- 这种TRIM32介导的INSR降解导致DIO小鼠严重的胰岛素抵抗和肝硬化.
- 肝脏特异性TRIM32敲击恢复INSR水平并改善肝脏的胰岛素敏感性.
结论:
- TRIM32是一种关键的E3无素酶,可以调解饮食诱导的肝脏胰岛素抵抗.
- 通过降解INSR,TRIM32促进胰岛素抵抗和脂肪肝.
- 准TRIM32可能为肥胖中代谢功能障碍提供治疗策略.
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