代谢过程. S- 化将与肥胖相关的炎症与内质网膜功能障碍联系在一起
Ling Yang1, Ediz S Calay1, Jason Fan1
1Department of Genetics and Complex Diseases and Sabri Ülker Center, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA.
概括
肥胖症的炎症通过可诱导的氧化合成酶 (iNOS) 活动损害了内分泌网膜 (ER) 的应激反应. 这会损害ER平衡和蛋白质功能,导致与肥胖相关的并发症.
科学领域:
- 细胞生物学
- 分子生物学
- 代谢疾病
背景情况:
- 慢性炎症和内质网膜 (ER) 压力与各种疾病有关.
- 慢性炎症对未折叠蛋白反应 (UPR) 和慢性病的ER稳态的调节作用尚不清楚.
研究的目的:
- 调查慢性炎症调节肥胖症中UPR和ER平衡的机制.
- 确定诱导性氧化合成酶 (iNOS) 和IRE1α在肥胖期间的ER压力中的作用.
主要方法:
- 在小鼠中利用遗传 (ob/ob) 和饮食 (高脂肪饮食) 的肥胖模型.
- 评估了iNOS活动对IRE1α S- 化和XBP1拼接的影响.
- 使用肝脏特异性IRE1α缺乏的小鼠和耐化IRE1α变体.
主要成果:
- 在肥胖小鼠中,iNOS活性增加导致IRE1α的S- 化,从而损害其功能.
- 这导致XBP1拼接活性降低,并损害了ER平衡.
- 在肥胖小鼠中恢复耐化IRE1α改善了XBP1拼接和葡萄糖代谢.
结论:
- 炎症途径,特别是INOS介导的IRE1α的S- 化,在肥胖症中破坏了UPR功能.
- 这种机制有助于IRE1α活动的缺陷,ER功能受损,以及肥胖中持续的ER压力.
- 针对这种途径可能为与肥胖相关的代谢功能障碍提供治疗策略.
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