人們都知道鍛煉身體可以促進新陳代謝,，有益于心血管健康,，但此前科學(xué)家對運動究竟如何影響心臟卻所知甚少。美國哈佛大學(xué)醫(yī)學(xué)院的研究人員日前報告說,，他們首次從分子水平發(fā)現(xiàn)運動有益心臟健康的機理,，這一發(fā)現(xiàn)將有助于開發(fā)出治療心血管疾病的新療法。
研究人員通過小鼠實驗發(fā)現(xiàn),，經(jīng)常運動可以使小鼠體內(nèi)的C／EBPb轉(zhuǎn)錄因子水平顯著下降,，其結(jié)果會促進小鼠心臟肌肉細(xì)胞增殖，有益于心臟生長,。此外,，研究人員還發(fā)現(xiàn)，體內(nèi)C／EBPb水平較低的小鼠對心力衰竭具有抵抗能力,。
研究人員表示,，這項研究對心臟肌肉再生的潛力有了深入理解。參與研究的哈佛大學(xué)醫(yī)學(xué)院教授安東尼·羅森茨魏希表示,，通過這項研究可以開發(fā)出針對那些無法運動的心臟病患者的療法,。
這項研究成果發(fā)表在新一期美國《細(xì)胞》雜志上。（生物谷Bioon.com）
生物谷推薦原文出處：
Cell doi：10.1016/j.cell.2010.11.036
C/EBPβ Controls Exercise-Induced Cardiac Growth and Protects against Pathological Cardiac Remodeling
Authors
Pontus Bostr?m, Nina Mann, Jun Wu, Pablo A. Quintero, Eva R. Plovie, Daniela Panáková, Rana K. Gupta, Chunyang Xiao, Calum A. MacRae, Anthony Rosenzweig, Bruce M. Spiegelman
Highlights
Endurance exercise of mice induces cardiomyocyte proliferation
Endurance exercise causes a reduction of C/EBPβ expression and an increase of CITED4
Reduction of C/EBPβ in vitro induces cellular hypertrophy and proliferation via CITED4
Genetic reduction of C/EBPβ in vivo results in a phenocopy of the exercised heart
Summary
The heart has the ability to grow in size in response to exercise, but little is known about the transcriptional mechanisms underlying physiological hypertrophy. Adult cardiomyocytes have also recently been proven to hold the potential for proliferation, a process that could be of great importance for regenerative medicine. Using a unique RT-PCR-based screen against all transcriptional components, we showed that C/EBPβ was downregulated with exercise, whereas the expression of CITED4 was increased. Reduction of C/EBPβ in vitro and in vivo resulted in a phenocopy of endurance exercise with cardiomyocyte hypertrophy and proliferation. This proliferation was mediated, at least in part, by the increased CITED4. Importantly, mice with reduced cardiac C/EBPβ levels displayed substantial resistance to cardiac failure upon pressure overload. These data indicate that C/EBPβ represses cardiomyocyte growth and proliferation in the adult mammalian heart and that reduction in C/EBPβ is a central signal in physiologic hypertrophy and proliferation.
