Department of Cell and Developmental Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
J Mol Cell Cardiol. 2011 Jun;50(6):1056-8. doi: 10.1016/j.yjmcc.2011.02.015. Epub 2011 Mar 5.
Homeodomain only protein x (Hopx) is an unusual homeodomain protein that has diverse effects on cardiac growth. Manipulation of Hopx function in murine models is associated with cardiac hypertrophy, dilation and fibrosis. In the present study, we examined the expression profile of Hopx in various models of pathologic cardiac hypertrophy and failure. Hopx expression is significantly reduced in neonatal rat cardiac myocytes after α/β adrenergic receptor agonist treatment. Cardiac hypertrophy and failure induced by transaortic constriction in mice causes marked down-regulation of Hopx expression. Interestingly, HOPX expression was significantly reduced in hearts of humans with end-stage heart failure when compared to non-failing control hearts, and HOPX levels remain low after LVAD support. Our findings suggest that HOPX/Hopx expression is reduced in multiple examples of human and murine cardiac hypertrophy and failure.
同源域仅蛋白 X（Hopx）是一种不寻常的同源域蛋白，对心脏生长有多种影响。在鼠模型中对 Hopx 功能的操作与心脏肥大、扩张和纤维化有关。在本研究中，我们检查了 Hopx 在各种病理性心脏肥大和衰竭模型中的表达谱。α/β 肾上腺素能受体激动剂处理后，新生大鼠心肌细胞中的 Hopx 表达显著降低。转主动脉缩窄引起的小鼠心脏肥大和衰竭导致 Hopx 表达明显下调。有趣的是，与非衰竭对照心脏相比，终末期心力衰竭患者的心脏中 HOPX 表达显著降低，并且在 LVAD 支持后 HOPX 水平仍然较低。我们的发现表明，Hopx 在多种人类和鼠类心脏肥大和衰竭的模型中表达减少。
