权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

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

在从成年大鼠分离的单个心肌细胞中，我们使用新设计的荧光成像系统研究了细胞内氧浓度、线粒体氧化代谢、细胞内 ATP 浓度和线粒体膜电位的变化。在生理氧浓度（3%-5%）下，氧化磷酸化解偶联剂提高线粒体氧通量，促进坏死细胞死亡。由于这些细胞中线粒体膜电位的变化最小，因此氧通量的增加似乎严重影响细胞在缺氧条件下的存活。抑制肌酸激酶（CK）后观察到的细胞死亡明显加速。在氧通量升高的 CK 抑制心肌细胞中，细胞核心的膜电位几乎被消除，这与我们之前关于单个心肌细胞（缺氧细胞核心）内氧浓度径向梯度的发现一致。缺氧核心中线粒体膜电位的破坏会将 F_1F_0-ATP 合酶（复合体 V）转变为 ATP 酶。如果发生这种情况，不仅氧化性 ATP 生产无法进行，而且缺氧核心的线粒体中也会发生 ATP 的大量消耗。这种ATP的缺乏，尽管限制在细胞核心，很快就会扰乱ATPase依赖性的细胞内Ca^2+调节，并且Ca^2+超载最终会导致细胞死亡。然而，在正常心肌细胞中，PCr-CK系统可以通过扩散将高能磷酸盐从细胞表面（氧气充足并且氧化ATP的产生不受阻碍）供应到缺氧的细胞核心。因此，最初在细胞表面附近的线粒体中产生的PCr会向缺氧细胞核心的线粒体补充ATP，从而维持线粒体膜电位，而无需呼吸链中的电子传递。该机制可以显着延缓线粒体的功能性分解和随后的Ca 2+ 超载。因此，PCr-CK系统可能是保护呼吸心肌细胞免遭缺氧死亡的内在机制。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）

In vivo oxygen imaging using green fluorescent protein

DOI：
10.1152/ajpcell.00067.2006
发表时间：
2006-10-01
期刊：
AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY
影响因子：
5.5
作者：
Takahashi, Eiji;Takano, Tomohiro;Sato, Michihiko
通讯作者：
Sato, Michihiko

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 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

Aged mouse oocytes fail to readjust intracellular adenosine triphosphates at fertilization