Mechanisms of Cell Death in Cardiomyopathy

心肌病细胞死亡的机制

• 批准号: 6369964
• 负责人: TUAN H KUO
• 金额: $ 27.35万
• 依托单位: WAYNE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-07-01 至 2005-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6369964
• 关键词: JUN kinase; apoptosis; calcium flux; calcium transporting ATPase; cardiac myocytes; cell death; enzyme activity; gender difference; genetically modified animals; hamsters; immunoprecipitation; in situ hybridization; laboratory mouse; laboratory rat; membrane permeability; membrane transport proteins; mitochondria; molecular cloning; myocardium disorder; northern blottings; pathologic process; polymerase chain reaction; sarcoplasmic reticulum; tissue /cell culture

DESCRIPTION (provided by applicant): The long-term goal of this project is to elucidate the mechanism of Ca2+ -mediated cell death in cardiomyopathy. It is our hypothesis that altered Ca2+ homeostasis and unbalanced signal transduction can lead to mitochondrial dysfunction and cell death. We propose: 1. To study the regulation of mitochondrial Ca2+ (Cam) by the mitochondrial Na/Ca exchanger (NCE) and the permeability transition (MPT) pore in isolated organelle or cultured myocytes. 2. To study the effect of proapoptotic signal transduction on mitochondria by comparing the sensitivity to Ca2+ mediated death and mitochondrial function (Cam load, delta psi, NCE activity and MPT) in cells that overexpress the stress-activated kinase JNK with cells that expressing mutant inactive-JNK. 3. To study the development of cardiomyopathy in the Syrian hamster. The development of lesion in the myopathic heart will be followed at pre-necrotic- (1 mo), necrotic- (2 mo.) and post necrotic- (3 mo.) stage. The changes in the heart will be correlated with studies in isolated myocytes and mitochondria. The parameters to be monitored are mitochondrial Cam load, abnormal NCE activity, JNK/ERK activation, and susceptibility to Ca2+ -induced permeability transition. Intervention of cardiomyopathy will be carried out by diltiazem treatment, and heart tissue or mitochondria examined for the prevention of lesion development and for the reversal of abnormal Ca2+ homeostasis and NCE activity. 4. To study the effects of sarcolemmal Na/Ca exchanger (NCX1) overexpression on mitochondrial function and cell injury in transgenic mice. The mechanism for the gender-specific increase in susceptibility to Ca2+ -mediated injury, and the upregulation of mitochondrial NCE activity in association with NCX 1 overexpression will be tested. The direct effect of estrogen (E2) on the activation of growth promoting kinase ERK, and on Ca2+ homeostasis during metabolic stress will also be examined in normal rat myocytes and compared to transgenic myocytes. These studies are designed to advance a poorly understood topic, that is the role of mitochondrial calcium homeostasis and signal transduction in cell survival and cardiomyopathy. We will examine new aspects in the mechanism of cell death and expect the results to be highly relevant to our understanding of gender- specific myocyte function in normal and disease states.

描述（由申请人提供）：本项目的长期目标是 阐明心肌病中Ca ~（2+）介导的细胞死亡机制。是 我们的假设是，改变了Ca 2+稳态和不平衡的信号转导 会导致线粒体功能障碍和细胞死亡我们建议：1.研究 线粒体Na/Ca交换对Ca ~（2+）的调节 (NCE)和分离的细胞器中的渗透性转换（MPT）孔，或 培养的心肌细胞2.研究促凋亡信号转导通路的作用 通过比较对Ca 2+介导的死亡的敏感性， 细胞中的线粒体功能（Cam负荷、Δ psi、NCE活性和MPT） 过表达应激激活激酶JNK的细胞， 突变型失活JNK。3.目的：研究老年人心肌病的发生发展， 叙利亚仓鼠。肌病性心脏病变的发展将是 分别在坏死前（1个月）、坏死（2个月）和坏死后-（3个月） 阶段心脏的变化将与孤立的研究相关。 肌细胞和线粒体。要监测的参数是线粒体Cam 负荷、异常NCE活性、JNK/ERK激活和对Ca 2+的敏感性 - 诱导的渗透性转变。心肌病的干预将是 通过地尔硫卓治疗进行，并检查心脏组织或线粒体 预防病变发展和逆转异常Ca 2 + 稳态和NCE活性。4.研究肌膜Na/Ca比值对心肌细胞凋亡的影响， NCX 1过表达对线粒体功能和细胞损伤的影响 转基因小鼠。按性别分列的增加 对Ca 2+介导的损伤的敏感性，以及线粒体膜电位的上调， 将测试与NCX 1过表达相关的NCE活性。的 雌激素（E2）对促生长激酶激活的直接作用 ERK和代谢应激期间Ca 2+稳态的影响也将在 正常大鼠肌细胞并与转基因肌细胞进行比较。这些研究 旨在推进一个知之甚少的话题，那就是 线粒体钙稳态和细胞存活中的信号转导， 心肌病我们将研究细胞死亡机制的新方面 并期望结果与我们对性别的理解高度相关- 正常和疾病状态下的特定肌细胞功能。