帕尔米酸诱导的胰岛素耐药性会导致行为丝硬化和GLUT4错误排序,而不会改变Akt信号传输
Victoria L Tokarz1,2, Sivakami Mylvaganam2,3, Amira Klip1,3
1Department of Physiology, University of Toronto, Ontario, M5S 1A8, Canada.
Journal of cell science
|October 10, 2023
概括
像棕酸盐这样的和脂肪会扰乱肌肉细胞中的葡萄糖运输体4型 (GLUT4) 运动,导致胰岛素抵抗. 这在不影响关键信号通路的情况下发生,突出显示了一种新的细胞机制,有助于2型糖尿病.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 代谢疾病 代谢疾病
背景情况:
- 骨肌肉对胰岛素的抵抗是2型糖尿病的主要驱动因素.
- 胰岛素抵抗的特点是由于缺陷的葡萄糖载体4型 (GLUT4) 转位而导致葡萄糖吸收受损.
- 和脂肪诱导胰岛素抵抗的确切机制尚不清楚.
研究的目的:
- 为了研究和脂肪的棕酸 (PA) 是如何导致骨肌细胞的胰岛素抵抗.
- 为了阐明由palmitate诱导的缺陷GLUT4转位背后的分子机制.
- 确定改善肌肉葡萄糖吸收的潜在治疗点.
主要方法:
- 利用骨肌肉的肌囊细胞和肌管来建模胰岛素抵抗.
- 在暴露于palmitate后评估GLUT4转位和局部化.
- 检查了胰岛素信号通路,包括Akt2和AS160 (TBC1D4).
- 研究了蛋白质棕化和内质网膜 (ER) 应激在调解棕酸盐效应中的作用.
- 分析了actin丝的刚度和Rac1活动.
主要成果:
- 帕尔米他因损害GLUT4转位而引起胰岛素耐药性,而不会影响Akt2或AS160信号传输.
- 帕尔米改变了基底状态GLUT4局部化,促进了周核积累.
- 帕尔米增加了雅丁丝的刚性,抑制了Rac1依赖的雅丁重塑.
- 蛋白质棕化和ER压力被确定为棕酸盐触发的关键机制.
结论:
- 像棕酸盐这样的和脂肪破坏了肌肉细胞中GLUT4转位的基本机制.
- 这些干扰涉及改变的GLUT4细胞内分类和受损的actin动态.
- 这些发现揭示了细胞自主失调,该失调使肌肉产生胰岛素抵抗,独立于正规的胰岛素信号缺陷.
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