二十碳五烯酸通过调节线粒体功能来防止神经酰胺对 C6 神经胶质瘤细胞的毒性作用。

Functional modulation of mitochondria by eicosapentaenoic acid provides protection against ceramide toxicity to C6 glioma cells.

机构信息

Department of General Surgery, Cathay General Hospital, Taipei 106, Taiwan.

出版信息

J Agric Food Chem. 2009 Dec 23;57(24):11455-62. doi: 10.1021/jf902021h.

DOI:10.1021/jf902021h

PMID:19921818

Abstract

Mitochondrial dysfunction and associated apoptosis have been reported in the pathogenesis of neuron degeneration. The effects of eicosapentaenoic acid (EPA) and arachidonic acid (AA) on the mitochondrial membrane potential, mitochondrial biogenesis, and mitochondrial function of rat C6 glioma cells were determined in this study. Increased cytochrome c release and activated caspase-3 expression were determined in cells treated with >20 microM C(2) ceramide. There were significant repressive effects on ceramide-induced cell death with 25-100 microM EPA and 25 microM AA pretreatment. However, significantly increased membrane potentials were detected in cells pretreated with 25 and 50 microM EPA compared to ceramide-treated cells, but not in AA pretreatment groups. In cells pretreated with EPA, ATP production loss was prevented from ceramide-induced mitochondrial dysfunction. In mitochondrial biogenesis related assay, both EPA and AA enhanced peroxisome proliferator-activated receptor gamma-coactivator-1alpha (PGC-1alpha) and mitochondrial transcription factor A (Tfam) transcriptional activities. However, elevated PGC-1alpha transcriptional activities in groups pretreated with 25, 50, and 100 microM EPA and only in the 100 microM AA group were analyzed. The Tfam transcriptional activities were enhanced in groups pretreated with 25 and 50 microM EPA and AA. Increased NADH dehydrogenase subunit 6 (ND6) mRNA expression was determined in cells pretreated with 25 and 50 microM EPA and 25 microM AA. Elevated protein levels of Tfam, flavoprotein, and cytochrome oxidase subunit III (COX III) were determined in cells pretreated with 25 and 50 microM EPA. The EPA-provided a more protective effect than AA against ceramide-induced cell death, which might mainly be due to maintaining the membrane potential and sustaining the mitochondrial ATP production function. EPA has more potential to elevate mitochondrial biogenesis through enhanced PGC-1alpha, and Tfam transcriptional activities may provide partial protection against ceramide cytotoxicity.

摘要

线粒体功能障碍和相关的细胞凋亡已被报道参与神经元退行性病变的发病机制。本研究旨在探讨二十碳五烯酸（EPA）和花生四烯酸（AA）对大鼠 C6 神经胶质瘤细胞线粒体膜电位、线粒体生物发生和线粒体功能的影响。用＞20μM C2 神经酰胺处理细胞后，检测到细胞色素 c 释放增加和半胱天冬酶-3 激活表达。用 25-100μM EPA 和 25μM AA 预处理可显著抑制神经酰胺诱导的细胞死亡。然而，与神经酰胺处理组相比，用 25 和 50μM EPA 预处理的细胞检测到明显增加的膜电位，但在 AA 预处理组中未检测到。在 EPA 预处理的细胞中，ATP 产生的损失被阻止，从而防止了由神经酰胺诱导的线粒体功能障碍。在线粒体生物发生相关的测定中，EPA 和 AA 均增强过氧化物酶体增殖物激活受体γ共激活因子-1α（PGC-1α）和线粒体转录因子 A（Tfam）的转录活性。然而，仅在 100μM AA 组和用 25、50 和 100μM EPA 预处理的组中分析到 PGC-1α转录活性的升高。用 25 和 50μM EPA 和 AA 预处理的组中 Tfam 的转录活性增强。在用 25 和 50μM EPA 和 25μM AA 预处理的细胞中，NADH 脱氢酶亚单位 6（ND6）mRNA 表达增加。在用 25 和 50μM EPA 预处理的细胞中，Tfam、黄素蛋白和细胞色素氧化酶亚基 III（COX III）的蛋白水平升高。EPA 对神经酰胺诱导的细胞死亡提供了比 AA 更强的保护作用，这可能主要是由于维持了膜电位并维持了线粒体 ATP 产生功能。EPA 通过增强 PGC-1α 更有潜力提高线粒体生物发生，Tfam 的转录活性可能对神经酰胺细胞毒性提供部分保护。