Superoxide Flashes Reveal Novel Properties of Mitochondrial Reactive   Oxygen Species Excitability in Cardiomyocytes

doi:10.1016/j.bpj.2012.01.044

CORC > 北京大学 > 生命科学学院

	Superoxide Flashes Reveal Novel Properties of Mitochondrial Reactive Oxygen Species Excitability in Cardiomyocytes
	Li, Kaitao ; Zhang, Wanrui ; Fang, Huaqiang ; Xie, Wenjun ; Liu, Jie ; Zheng, Ming ; Wang, Xianhua ; Wang, Wang ; Tan, Wenchang ; Cheng, Heping
刊名	biophysical journal
	2012
关键词	PERMEABILITY TRANSITION PORE CARDIAC MYOCYTES CA2+ SPARKS OXIDATIVE-STRESS SKELETAL-MUSCLE CALCIUM SPARKS METABOLISM RELEASE ACTIVATION DISEASE
DOI	10.1016/j.bpj.2012.01.044
英文摘要	Superoxide flash represents quantal and bursting production of mitochondrial reactive oxygen species (ROS) instigated by transient opening of the mitochondrial permeability transition pore (mPTP). Given their critical role in metabolism, ischemia-reperfusion injury, and apoptosis, characterization of flash properties would be valuable to further mechanistic and physiological studies of this newly discovered mitochondrial phenomenon. Here we developed the flash detector FlashSniper based on segmentation of two-dimensional feature maps extracted from time-lapse confocal image stacks, and on the theory for correcting optical distortion of flash-amplitude histograms. Through large-scale analysis of superoxide flashes in cardiomyocytes, we demonstrated uniform mitochondrial ROS excitability among subsarcolemmal and intermyofibrillar mitochondria, and exponential distribution of intervals between consecutive flash events. Flash ignition displayed three different patterns: an abrupt rise from quiescence (44%), a rise with an exponential foot (27%), or a rise occurring after a pedestal precursor (29%), closely resembling action-potential initiation in excitable cells. However, the optical blurring-corrected amplitudes of superoxide flashes were highly variable, as were their durations, indicating stochastic automaticity of single-mitochondrion ROS excitation. Simultaneous measurement of mitochondrial membrane potential revealed that graded, rather than all-or-none, depolarization mirrored the precursor and the primary peak of the flash. We propose that superoxide flash production is a regenerative process dominated by stochastic, autonomous recruitment of a limited number of units (e.g., mPTPs) in single mitochondria.; Biophysics; SCI(E); PubMed; 16; ARTICLE; 5; 1011-1021; 102
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/153986]
专题	生命科学学院工学院
推荐引用方式 GB/T 7714	Li, Kaitao,Zhang, Wanrui,Fang, Huaqiang,et al. Superoxide Flashes Reveal Novel Properties of Mitochondrial Reactive Oxygen Species Excitability in Cardiomyocytes[J]. biophysical journal,2012.
APA	Li, Kaitao.,Zhang, Wanrui.,Fang, Huaqiang.,Xie, Wenjun.,Liu, Jie.,...&Cheng, Heping.(2012).Superoxide Flashes Reveal Novel Properties of Mitochondrial Reactive Oxygen Species Excitability in Cardiomyocytes.biophysical journal.
MLA	Li, Kaitao,et al."Superoxide Flashes Reveal Novel Properties of Mitochondrial Reactive Oxygen Species Excitability in Cardiomyocytes".biophysical journal (2012).