Aries Anne, Paradis Pierre, Lefebvre Chantal, Schwartz Robert J, Nemer Mona
Laboratory of Cardiac Growth and Differentiation, Institut de Recherches Cliniques de Montréal, Montréal, QC, Canada H2W 1R7.
Proc Natl Acad Sci U S A. 2004 May 4;101(18):6975-80. doi: 10.1073/pnas.0401833101. Epub 2004 Apr 20.
In recent years, significant progress has been made in understanding cardiomyocyte differentiation. However, little is known about the regulation of myocyte survival despite the fact that myocyte apoptosis is a leading cause of heart failure. Here we report that transcription factor GATA-4 is a survival factor for differentiated, postnatal cardiomyocytes and an upstream activator of the antiapoptotic gene Bcl-X. An early event in the cardiotoxic effect of the antitumor drug doxorubicin is GATA-4 depletion, which in turn causes cardiomyocyte apoptosis. Mouse heterozygotes for a null Gata4 allele have enhanced susceptibility to doxorubicin cardiotoxicity. Genetic or pharmacologic enhancement of GATA-4 prevents cardiomyocyte apoptosis and drug-induced cardiotoxicity. The results indicate that GATA-4 is an antiapoptotic factor required for the adaptive stress response of the adult heart. Modulation of survival/apoptosis genes by tissue-specific transcription factors may be a general paradigm that can be exploited effectively for cell-specific regulation of apoptosis in disease states.
近年来,在理解心肌细胞分化方面取得了重大进展。然而,尽管心肌细胞凋亡是心力衰竭的主要原因,但对于心肌细胞存活的调控却知之甚少。在此我们报告,转录因子GATA-4是分化的出生后心肌细胞的存活因子,也是抗凋亡基因Bcl-X的上游激活剂。抗肿瘤药物阿霉素心脏毒性作用的早期事件是GATA-4缺失,这进而导致心肌细胞凋亡。Gata4基因无效等位基因的小鼠杂合子对阿霉素心脏毒性的易感性增强。GATA-4的基因或药理学增强可预防心肌细胞凋亡和药物诱导的心脏毒性。结果表明,GATA-4是成年心脏适应性应激反应所需的抗凋亡因子。组织特异性转录因子对存活/凋亡基因的调节可能是一种普遍模式,可有效用于疾病状态下细胞特异性凋亡调控。