Multiple influences of blood flow on cardiomyocyte hypertrophy in the embryonic zebrafish heart
Multiple influences of blood flow on cardiomyocyte hypertrophy in the embryonic zebrafish heart
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DOI：
10.1016/j.ydbio.2011.12.005
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发表时间：
2012-02-15
影响因子：
2.7
通讯作者：
Yelon, Deborah
中科院分区：
文献类型：
--
作者：
Lin, Yi-Fan;Swinburne, Ian;Yelon, Deborah
心肌细胞肥大是一种复杂的细胞行为，涉及细胞大小扩张和肌原纤维含量增加的协调。在这里，我们研究了心肌细胞肥大对心室出现的贡献，在此过程中原始心管转变为形态上不同的心室并增加其收缩强度。着眼于斑马鱼心室的出现，我们观察到细胞表面积和肌原纤维含量增加的趋势。为了检查这些趋势在多大程度上反映了单个心室心肌细胞的协调肥大，我们开发了一种跟踪活胚胎中细胞表面积变化和肌原纤维动态的方法。我们的数据揭示了心室出现过程中心室心肌细胞行为的先前未被认识到的异质性：尽管心肌细胞肥大很普遍，但许多细胞在观察到的时间范围内并未增加其表面积或肌原纤维含量。尽管细胞行为存在异质性，但我们经常发现肥大细胞彼此相邻。接下来，我们研究了血流对这一发育阶段心肌细胞行为调节的影响。当流经心室的血流量减少时，细胞表面积的扩张和肌原纤维含量的增加都会受到抑制，并且邻近细胞的行为似乎不协调。总之，我们的研究提出了一个模型，其中血流动力学对心室出现具有多种影响：促进心肌细胞增大和肌原纤维成熟，增强心肌细胞肥大的程度，并促进邻近细胞行为的协调。 (C) 2011 Elsevier Inc. 保留所有权利。
Cardiomyocyte hypertrophy is a complex cellular behavior involving coordination of cell size expansion and myofibril content increase. Here, we investigate the contribution of cardiomyocyte hypertrophy to cardiac chamber emergence, the process during which the primitive heart tube transforms into morphologically distinct chambers and increases its contractile strength. Focusing on the emergence of the zebrafish ventricle, we observed trends toward increased cell surface area and myofibril content. To examine the extent to which these trends reflect coordinated hypertrophy of individual ventricular cardiomyocytes, we developed a method for tracking cell surface area changes and myofibril dynamics in live embryos. Our data reveal a previously unappreciated heterogeneity of ventricular cardiomyocyte behavior during chamber emergence: although cardiomyocyte hypertrophy was prevalent, many cells did not increase their surface area or myofibril content during the observed timeframe. Despite the heterogeneity of cell behavior, we often found hypertrophic cells neighboring each other. Next, we examined the impact of blood flow on the regulation of cardiomyocyte behavior during this phase of development. When blood flow through the ventricle was reduced, cell surface area expansion and myofibril content increase were both dampened, and the behavior of neighboring cells did not seem coordinated. Together, our studies suggest a model in which hemodynamic forces have multiple influences on cardiac chamber emergence: promoting both cardiomyocyte enlargement and myofibril maturation, enhancing the extent of cardiomyocyte hypertrophy, and facilitating the coordination of neighboring cell behaviors. (C) 2011 Elsevier Inc. All rights reserved.