在衰老过程中导致mtDNA释放,并驱动SASP
Stella Victorelli1,2, Hanna Salmonowicz1,2,3,4, James Chapman3
1Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA.
Nature
|October 11, 2023
概括
细胞衰老通过与衰老相关的分泌表型 (SASP) 触发与年龄相关的功能障碍. 在老化细胞中抑制线粒体外膜通透 (MOMP) 会减少炎症并延长小鼠的健康寿命.
科学领域:
- 细胞生物学
- 老龄化研究
- 线粒体生物学
背景情况:
- 衰老细胞通过衰老相关的分泌表型 (SASP) 导致与年龄相关的组织功能障碍.
- 线粒体对SASP进行调节,但确切的机制尚不清楚.
- 线粒体外膜透 (MOMP) 是细胞亡的一个关键事件,与衰老不同.
研究的目的:
- 研究线粒体在细胞衰老和SASP中的作用.
- 阐明将线粒体动力学与SASP诱导联系在一起的机制.
- 探索针对老化中的线粒体路径的治疗策略.
主要方法:
- 在老化细胞中的线粒体外膜透性 (MOMP) 的表征.
- 在少数MOMP (miMOMP) 中分析BAX和BAK的作用.
- 评估线粒体DNA (mtDNA) 的释放和cGAS-STING通路的激活.
- 在老年小鼠体内研究,以评估MOMP抑制对炎症和健康的影响.
主要成果:
- 线粒体外膜透 (MOMP) 在线粒体的一个子集 (少数MOMP或miMOMP) 被确定为细胞衰老的特征.
- 这导致线粒体DNA (mtDNA) 释放到细胞质中.
- 细胞质mtDNA激活了cGAS-STING通路,这是SASP的一个关键调节器.
- 在体内抑制MOMP降低了炎症标志物,改善了老鼠的健康状况.
结论:
- 细胞衰老和细胞亡具有类似的线粒体依赖的调节机制.
- 潜在的线粒体亡应激,特别是miMOMP,是SASP的重要驱动因素.
- 抑制miMOMP诱导的炎症是一种潜在的治疗策略,可以改善老化中的健康状况.
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