瘤坏死因子-α诱导的心力衰竭中的线粒体异常与受损的DNA修复活动有关
1Cardiovascular Institute, Center for Biological Imaging, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
Circulation
|November 14, 2001
概括
线粒体DNA修复活性降低导致过度表达TNF-alpha的小鼠心力衰竭. 这表明TNF-alpha可能通过线粒体功能障碍和DNA突变调解心脏损伤.
科学领域:
- 心血管生物学 心血管生物学
- 线粒体医学 线粒体医学
- 分子心脏病学分子心脏病学
背景情况:
- 心脏线粒体DNA (mtDNA) 突变与扩张性心肌病相关.
- 调节心脏mtDNA突变的机制基本上是未知的.
- 瘤坏死因子-α (TNF-α) 的过度表达会在小鼠中诱导心力衰竭.
研究的目的:
- 研究心脏mtDNA修复机制,损伤和线粒体结构/功能.
- 阐明TNF-alpha在心脏线粒体改变中的作用.
- 确定TNF-alpha,mtDNA突变和心力衰竭病因之间的联系.
主要方法:
- 评估mtDNA修复活性 (mtUDG,基切除修复).
- 使用Fpg蛋白消化和南方斑块量化mtDNA损伤.
- 通过电子显微镜检查线粒体超结构.
- 测量了线粒体功能 (细胞氧化酶,糖酸脱酶) 和ATP含量.
主要成果:
- 在TNF1.6小鼠心脏中显著减少mtUDG和基切除修复活动.
- 心脏mtDNA中的Fpg敏感部位增加,表明mtDNA损伤增加.
- 显著降低心脏细胞染色体c氧化酶活性和改变线粒体形态.
- 观察到从氧化酸化转变为糖解 (增加LDH,ALT,乳酸/酸盐比率).
结论:
- 减少mtDNA修复活性与TNF-α诱导的心力衰竭中的mtDNA突变和线粒体功能障碍有关.
- TNF-α对心脏的有害影响可能涉及线粒体的结构和功能变化.
- mtDNA修复缺陷可能是TNF-α介导心脏病理的一个关键因素.
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