脂肪细胞NCoR淘汰会降低PPARγ的酸化,并增强PPARγ活性和胰岛素敏感性
Pingping Li1, Wuqiang Fan, Jianfeng Xu
1Division of Endocrinology and Metabolism, Department of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.
Cell
|November 15, 2011
概括
核受体核心压缩器 (NCoR) 在脂肪细胞中的淘汰改善了肥胖小鼠的葡萄糖耐受性和胰岛素敏感性. 删除NCoR可以减少炎症并增强脂肪细胞功能,模仿糖尿病药物的效果.
科学领域:
- 代谢性疾病研究研究.
- 脂肪细胞生物学 脂肪细胞生物学
- 分子内分泌学分子内分泌学
背景情况:
- 肥胖和2型糖尿病的特点是胰岛素抵抗,炎症和功能障碍的脂肪组织.
- 核受体核心压缩器 (NCoR) 在调节基因表达方面发挥作用,但其在脂肪细胞中关于代谢平衡的特定功能尚未完全理解.
研究的目的:
- 研究NCoR在脂肪细胞生物学中的作用及其对全身葡萄糖和胰岛素平衡的影响.
- 阐明NCoR影响脂肪细胞功能和胰岛素敏感性的分子机制.
主要方法:
- 生成脂肪细胞特异性NCoR淘汰赛 (AKO) 鼠标.
- 评估葡萄糖耐受性,胰岛素敏感性使用紧固件研究.
- 脂肪组织炎症,巨细胞透和基因表达的分析.
- 研究NCoR,CDK5和PPARγ之间的相互作用.
主要成果:
- 尽管肥胖增加,但AKO小鼠表现出改善的葡萄糖耐受性和肝脏,肌肉和脂肪组织中增强的胰岛素敏感性.
- 在AKO小鼠中的脂肪组织显示了巨细胞透和炎症的减少.
- 在AKO小鼠中,PPARγ目标基因表达被上调,CDK5-介导的PPARγ在ser-273的酸化被降低.
- NCoR被确定为一种适应蛋白,促进CDK5-介导的PPARγ酸化.
结论:
- 脂肪细胞NCoR通过促进其酸化来转抑制PPARγ活性.
- 删除脂肪细胞NCoR会导致增强脂肪生成,减少炎症和改善全身胰岛素敏感性.
- 这些发现表明,NCoR是代谢障碍的潜在治疗标,NCoR删除可复制 thiazolidinediones (TZDs) 的作用.
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