Dysregulation of very long chain acyl-CoA dehydrogenase coupled with lipid peroxidation
Dysregulation of very long chain acyl-CoA dehydrogenase coupled with lipid peroxidation
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DOI：
10.1152/ajpcell.00231.2009
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发表时间：
2010-01-01
影响因子：
5.5
通讯作者：
Homma, Yoshimi
中科院分区：
文献类型：
--
作者：
Kabuyama, Yukihito;Suzuki, Toshiyuki;Homma, Yoshimi
[10]张文忠，张文忠.极长链酰基辅酶A脱氢酶调节异常伴脂质过氧化。美国生理学杂志细胞生理学298：C107-C113，2010年。首次发表于2009年11月4日; doi：10.1152/ajpcell.00231.2009。特发性肺纤维化（IPF）是一种病因不明的慢性进行性肺部疾病。我们先前揭示了在从患有IPF的病变肺组织建立的培养细胞系中增加的氧化应激和抗氧化蛋白的高表达（Kabuyama Y，Oshima K，Kitamura T，Homma M，Yamaki J，Munakata M，Homma Y. Genes Cells 12：1235-1244，2007）。在这项研究中，我们表明，IPF细胞含有高水平的游离胆固醇和其过氧化形式相比，正常的TIG 7肺成纤维细胞，这表明，自由基氧物种（ROS）内产生特定的细胞器。为了理解IPF细胞中ROS产生的分子基础，我们对来自TIG和IPF细胞的线粒体蛋白进行了蛋白质组学分析。该分析显示极长链酰基-CoA脱氢酶（VLCAD）的Ser 586的磷酸化在IPF细胞中显著降低。用抗-pS586抗体进行免疫印迹得到类似的结果。来自IPF细胞的对含有Ser 586的肽的激酶活性显著低于来自TIG细胞的激酶活性。此外，磷酸化阴性突变体（S586 A）VLCAD显示出降低的电子传递活性和对脂肪酸β-氧化的强显性负效应。S586 A突变体的异位表达诱导人胚肾（HEK）293细胞产生显著高量的氧化脂质和过氧化氢。表达S586 A突变体的HEK 293细胞表现出细胞生长的减少和细胞凋亡的增强。这些结果表明，一种新的调节机制，稳态VLCAD活动，其失调可能参与生产的氧化应激和IPF的发病机制。
Kabuyama Y, Suzuki T, Nakazawa N, Yamaki J, Homma MK, Homma Y. Dysregulation of very long chain acyl-CoA dehydrogenase coupled with lipid peroxidation. Am J Physiol Cell Physiol 298: C107-C113, 2010. First published November 4, 2009; doi:10.1152/ajpcell.00231.2009.-Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease of unknown etiology. We previously revealed increased oxidative stress and high expression of antioxidant proteins in culture cell lines established from lesional lung tissues with IPF (Kabuyama Y, Oshima K, Kitamura T, Homma M, Yamaki J, Munakata M, Homma Y. Genes Cells 12: 1235-1244, 2007). In this study, we show that IPF cells contain high levels of free cholesterol and its peroxidized form as compared with normal TIG7 lung fibroblasts, suggesting that radical oxygen species (ROS) are generated within specific organelles. To understand the molecular basis underlying the generation of ROS in IPF cells, we performed proteomic analysis of mitochondrial proteins from TIG and IPF cells. This analysis shows that the phosphorylation of Ser586 of very long chain acyl-CoA dehydrogenase (VLCAD) is significantly reduced in IPF cells. Similar results are obtained from immunoblotting with anti-pS586 antibody. Kinase activity toward a peptide containing Ser586 from IPF cells is significantly lower than that from TIG cells. Furthermore, a phosphorylation-negative mutant (S586A) VLCAD shows reduced electron transfer activity and a strong dominant-negative effect on fatty acid beta-oxidation. The ectopic expression of the S586A mutant induced human embryonic kidney (HEK) 293 cells to produce significantly high amounts of oxidized lipids and hydrogen peroxide. HEK293 cells expressing the S586A mutant exhibit a reduction in cell growth and an enhancement in apoptosis. These results suggest a novel regulatory mechanism for homeostatic VLCAD activity, whose dysregulation might be involved in the production of oxidative stress and in the pathogenesis of IPF.