Loss of p47phox Subunit Enhances Susceptibility to Biomechanical Stress and Heart Failure Because of Dysregulation of Cortactin and Actin Filaments
Loss of p47phox Subunit Enhances Susceptibility to Biomechanical Stress and Heart Failure Because of Dysregulation of Cortactin and Actin Filaments
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DOI：
10.1161/circresaha.111.300299
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发表时间：
2013-06-07
影响因子：
20.1
通讯作者：
Oudit, Gavin Y.
中科院分区：
文献类型：
--
作者：
Patel, Vaibhav B.;Wang, Zuocheng;Oudit, Gavin Y.
原理：经典的吞噬细胞烟酰胺腺嘌呤二核苷酸磷酸氧化酶(gp91(Phox)或NOX2)在心脏中表达。NOX2的激活需要p47(Phox)亚单位的膜转位，并与心力衰竭有关。目的：探讨p47(Phox)基因缺失在压力超负荷诱导的生物力学应激中的作用。方法与结果：8周龄雄性小鼠P47(Phox)基因缺失(P47(Phox)基因敲除[KO])、NOX2基因缺失(Nox2KO)和野生型小鼠造成压力超负荷。与我们的假设相反，P47(Phox)KO小鼠在横状主动脉狭窄后5周和9周表现出明显的收缩功能障碍，与野生型横状主动脉狭窄小鼠相比，压力超负荷导致收缩功能障碍明显恶化。我们发现，生物力学应力上调了P47(Phox)KO心脏N-钙粘附素和β-连环素的表达，但破坏了肌动蛋白细丝细胞骨架，减少了粘着斑激酶的磷酸化。在小鼠和人心脏中，p47(Phox)通过免疫共沉淀和双重免疫荧光染色与胞浆中的Cortactin相互作用，并在生物力学应力作用下移位到细胞膜上，在那里Cortactin与N-钙粘素相互作用，导致适应性细胞骨架重塑。然而，P47(Phox)KO心脏显示皮质蛋白与N-钙粘附素的相互作用减弱，导致生物力学应力诱导的肌动蛋白聚合和细胞骨架重塑的丧失。相反，NOX2不与皮质肌动蛋白相互作用，NOX2缺陷的心脏不受压力超负荷诱导的不利心肌和细胞内细胞骨架重构的保护。结论：我们发现P47(Phox)亚单位作为皮质肌动蛋白和适应性细胞骨架重构的调节因子具有超越和独立于烟酰胺腺嘌呤二核苷酸磷酸氧化酶活性的新作用，导致对生物机械应激和心力衰竭的易感性增强。
Rationale: The classic phagocyte nicotinamide adenine dinucleotide phosphate oxidase (gp91(phox) or Nox2) is expressed in the heart. Nox2 activation requires membrane translocation of the p47(phox) subunit and is linked to heart failure. We hypothesized that loss of p47(phox) subunit will result in decreased reactive oxygen species production and resistance to heart failure.Objective: To define the role of p47(phox) in pressure overload-induced biomechanical stress.Methods and Results: Eight-week-old male p47(phox) null (p47(phox) knockout [KO]), Nox2 null (Nox2KO), and wild-type mice were subjected to transverse aortic constriction-induced pressure overload. Contrary to our hypothesis, p47(phox)KO mice showed markedly worsened systolic dysfunction in response to pressure overload at 5 and 9 weeks after transverse aortic constriction compared with wild-type-transverse aortic constriction mice. We found that biomechanical stress upregulated N-cadherin and beta-catenin in p47(phox)KO hearts but disrupted the actin filament cytoskeleton and reduced phosphorylation of focal adhesion kinase. p47(phox) interacts with cytosolic cortactin by coimmunoprecipitation and double immunofluorescence staining in murine and human hearts and translocated to the membrane on biomechanical stress where cortactin interacted with N-cadherin, resulting in adaptive cytoskeletal remodeling. However, p47(phox)KO hearts showed impaired interaction of cortactin with N-cadherin, resulting in loss of biomechanical stress-induced actin polymerization and cytoskeletal remodeling. In contrast, Nox2 does not interact with cortactin, and Nox2-deficient hearts were protected from pressure overload-induced adverse myocardial and intracellular cytoskeletal remodeling.Conclusions: We showed a novel role of p47(phox) subunit beyond and independent of nicotinamide adenine dinucleotide phosphate oxidase activity as a regulator of cortactin and adaptive cytoskeletal remodeling, leading to a paradoxically enhanced susceptibility to biomechanical stress and heart failure.