线粒体调节成年心脏肌细胞的增殖
Gregory B Waypa1,2, Kimberly A Smith1,2, Paul T Mungai1,2
1Department of Pediatrics.
The Journal of clinical investigation
|May 9, 2024
概括
科学家将成人心脏细胞逆转为胎儿状态,恢复它们分裂和再生的能力. 这一发现为新的心脏再生疗法提供了潜力,通过增强葡萄糖利用率和减少线粒体功能.
科学领域:
- 心血管生物学 心血管生物学
- 线粒体功能的功能
- 细胞的新陈代谢
背景情况:
- 成年心肌细胞失去了细胞分裂的能力,转变为依赖于线粒体氧化酸化的表型.
- 这种从胎儿的糖溶性表型转变为成人的氧化表型限制了心脏的再生潜力.
研究的目的:
- 调查是否将成年心肌细胞恢复到胎儿的糖解状态可以恢复它们的增殖能力.
- 探索这种表型逆转背后的机制及其对心脏再生的影响.
主要方法:
- 在成年小鼠心脏中删除Uqcrfs1 (线粒体Rieske铁硫蛋白,RISP) 以损害线粒体功能.
- 对心脏重塑,细胞能量代谢,基因表达 (RNA测序) 和表观遗传修饰 (代谢学) 的分析.
主要成果:
- 减少RISP导致线粒体功能的减少和葡萄糖利用率的增加,促进了高可塑性重塑,其中心肌细胞数量在不增多的情况下翻了一番.
- 没有AMP激活蛋白激酶 (AMPK) 的激活,而哺乳动物的目标拉巴胺素 (mTOR) 的激活是明显的.
- 缺血性心脏中的RISP缺失促进了新的心肌细胞迁移到心脏病发作区域,RNA测序揭示了心脏发育和增殖基因的上调.
- 代谢分析表明,表观遗传修饰的基质改变,S-adenosylmethionine增加和α-ketoglutarate减少,与基因开始部位附近的CpG甲基化增加相关.
结论:
- 减少线粒体功能和增加葡萄糖利用率可以恢复成年心肌细胞的线粒体容量.
- 这个过程产生了新的心脏细胞,可能是通过表观遗传修饰来调节增殖基因.
- 这些发现表明通过操纵心肌细胞代谢和表观遗传状态来进行心脏再生的新治疗策略.
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