Bioimaging analysis of hypoxic cell death and its cellular defense mechanisms.

缺氧细胞死亡及其细胞防御机制的生物成像分析。

基本信息

批准号：
15390061
负责人：
TAKAHASHI Eiji
金额：
$ 7.23万
依托单位：
Yamagata University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2005
项目状态：
已结题

项目摘要

In single cardiomyocytes isolated from the adult rat, we investigated changes in intracellular oxygen concentration, mitochondrial oxidative metabolism, intracellular ATP concentration, and mitochondrial membrane potential using newly devised fluorescence imaging system. At physiological oxygen concentration (3%-5%),elevating oxygen flux to mitochondria by an uncoupler of oxidative phosphorylation promoted necrotic cell death. Because changes in the mitochondrial membrane potential in these cells were minimum, increases in the oxygen flux appeared to critically affect cell survival in hypoxia. Observed cell death was significantly accelerated after inhibition of creatine kinase (CK). In CK-inhibited cardiomyocytes with elevated oxygen flux, membrane potential was almost abolished in the cell core that is consistent with our previous findings regarding radial gradients of oxygen concentration within a single cardiomyocyte (anoxic cell core). Disruption of mitochondrial membrane potentia … More l in the anoxic core would turn the F_1F_0-ATP synthase (complex V) to an ATPase. If these happen, not only oxidative ATP production would be unable to proceed, but also massive consumption of ATP should break out in mitochondria in the anoxic core. This deficiency of ATP, albeit restricted in the cell core, quickly disturbs ATPase-dependent intracellular regulations of Ca^<2+>, and Ca^<2+> overload leading to cell death would finally commence. However, in the normal cardiomyocyte, the PCr-CK system may supply high energy phosphate from the cell surface (where oxygen is abundant and oxidative ATP production is not hampered) to the oxygen deficit cell core by diffusion. Thus, PCr originally produced in mitochondria near the cell surface would supplement ATP to the mitochondria in the anoxic cell core, so that mitochondrial membrane potential is maintained without electron transport in the respiratory chain. Functional disintegration of the mitochondria and following Ca^<2+> overload could be significantly retarded by this mechanism. Hence, the PCr-CK system may be an intrinsic mechanism that protects respiring cardiomyocytes against hypoxic death. Less

在从成年大鼠中分离出来的单个心肌细胞中，我们使用新设计的荧光成像系统研究了细胞内氧浓度，线粒体氧化物代谢，细胞内ATP浓度和线粒体膜电位的变化。在物理氧浓度（3％-5％）下，通过氧化物磷酸化的解偶联剂将氧气升高至线粒体，促进了坏死细胞死亡。由于这些细胞中线粒体膜电位的变化是最小的，因此氧气通量的增加似乎严重影响了缺氧的细胞存活。抑制创造激酶（CK）后观察到的细胞死亡显着加速。 In CK-inhibited cardiomyocytes with elevated oxygen flux, membrane potential was almost abolished in the cell core that is consistent with our previous findings regarding radial gradients of oxygen concentration within a single cardiomyocyte (anoxic cell Disruption of mitochondrial membrane potentialia … More l in the anoxic core would turn the F_1F_0-ATP synthase (complex V) to an ATPase. If these happen, not only oxidative ATP production would be unable to proceed, but also massive consumption of ATP should break out in mitochondria in the anoxic core. This deficiency of ATP, albeit restricted in the cell core, quickly disturbs ATPase-dependent intracellular regulation of Ca^<2+>, and Ca^<2+> overload leading to cell death would finally commence. However, in the normal cardiomyocyte, the PCr-CK system may supply high energy phosphate from the cell surface (where oxygen is abundant and oxidative ATP production is not hampered) to the oxygen deficient cell core by diffusion. That, PCr originally produced in mitochondria near the cell surface would supplement ATP to the mitochondria in the anoxic cell core, so that mitochondrial membrane potential is Maintained without electron transport in the respiratory chain.线粒体的功能分解和随后的CA^<2+>超负荷可能会受到这种机制的显着阻碍。因此，PCR-CK系统可能是一种固有机制，可保护呼吸心肌细胞免受低氧死亡的影响。较少的

项目成果

期刊论文数量（16）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Genetic oxygen sensor. GFP as an indicator of intracellular oxygenation.

遗传氧传感器。

DOI：
发表时间：
2005
期刊：
Adv.Exp.Med.Biol. (in press)
影响因子：
0
作者：
E.Takahashi et al.
通讯作者：
E.Takahashi et al.

Aged mouse oocytes fail to readjust intracellular adenosine triphosphates at fertilization

DOI：
10.1095/biolreprod.104.034926
发表时间：
2005-05-01
期刊：
BIOLOGY OF REPRODUCTION
影响因子：
3.6
作者：
Igarashi, H;Takahashi, T;Kurachi, H
通讯作者：
Kurachi, H

Aged mouse oocytes fail to readjust intracellular adenosine triphosphate at fertilization.

衰老的小鼠卵母细胞在受精时无法重新调整细胞内三磷酸腺苷。

DOI：
发表时间：
2005
期刊：
Biology of Reproduction 77
影响因子：
0
作者：
D.Shida;J.Kitayama;H.Yamaguchi;K.Hama;J.Aoki;H.Arai;H.Yamashita;K.Mori;A.Sako;T.Konishi;T.Watanabe;T.Sakai;R.Suzuki;H.Ohta;Y.Takuwa;H.Nagawa.;Igarashi H
通讯作者：
Igarashi H

GFP as an indicator of intracellular oxygenation.

GFP 作为细胞内氧合的指标。