线粒体RNA的细胞溶液泄漏驱动SASP
Stella Victorelli1,2, Madeline Eppard1,2, Seung-Hwa Woo1,2
1Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN 55905, USA.
Research square
|September 11, 2024
概括
衰老细胞中的线粒体RNA (mtRNA) 通过RNA传感器触发炎症,驱动衰老相关的分泌表型 (SASP). 抑制这种途径和BAX/BAK等关键蛋白质减少SASP,为衰老和MASH提供治疗潜力.
科学领域:
- 细胞衰老 细胞衰老
- 炎症和衰老的作用
- 线粒体生物学 线粒体生物学
背景情况:
- 衰老细胞释放促炎因素 (SASP),导致衰老和组织功能障碍.
- 线粒体功能障碍和随后的线粒体DNA (mtDNA) 释放激活cGAS/STING通路,影响SASP.
- 其他线粒体成分,如线粒体RNA (mtRNA) 在SASP调节中的作用仍然不太清楚.
研究的目的:
- 调查线粒体RNA (mtRNA) 在诱导衰老相关分泌表型 (SASP) 中的作用.
- 确定参与mtRNA泄漏及其随后的炎症信号的细胞机制和途径.
- 评估针对mtRNA介导SASP诱导的治疗潜力.
主要方法:
- 在衰老细胞中检测和分析细胞质mtRNA积累.
- 在mtRNA释放时对RNA传感器激活 (RIG-I,MDA5) 和下游信号 (MAVS) 的研究.
- 对RNA传感器的药理抑制和BAX/BAK的遗传删除,以评估SASP的减少.
- 评估SASP表达在体外和在代谢功能障碍相关的乳脂肝炎 (MASH) 的小鼠模型中.
主要成果:
- 在衰老细胞中观察到mtRNA的细胞质积累.
- mtRNA激活RIG-I和MDA5,导致MAVS聚合和随后的SASP诱导.
- 抑制RNA传感器显著降低了SASP因子.
- BAX和BAK蛋白对于老化期间的mtRNA泄漏至关重要,它们的删除显著减少了SASP表达.
结论:
- 线粒体RNA (mtRNA) 是老化相关分泌表型 (SASP) 的关键媒介,通过激活细胞质RNA传感器.
- 依赖BAX/BAK的mtRNA泄漏导致衰老和MASH中的炎症.
- 针对mtRNA介导的信号通路,为与年龄相关的炎症和MASH治疗提供了一个有前途的治疗策略.
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