Debbabi Meryam, Nury Thomas, Zarrouk Amira, Mekahli Nadia, Bezine Maryem, Sghaier Randa, Grégoire Stéphane, Martine Lucy, Durand Philippe, Camus Emmanuelle, Vejux Anne, Jabrane Aymen, Bretillon Lionel, Prost Michel, Moreau Thibault, Ammou Sofien Ben, Hammami Mohamed, Lizard Gérard
Team 'Biochemistry of the Peroxisome, Inflammation and Lipid Metabolism' EA 7270/INSERM, University Bourgogne Franche-Comté, 21000 Dijon, France.
Lab-NAFS 'Nutrition-Functional Food & Vascular Health', University Monastir, LR12ES05, 5000 Monastir, Tunisia.
Int J Mol Sci. 2016 Nov 25;17(12):1973. doi: 10.3390/ijms17121973.
Lipid peroxidation products, such as 7-ketocholesterol (7KC), may be increased in the body fluids and tissues of patients with neurodegenerative diseases and trigger microglial dysfunction involved in neurodegeneration. It is therefore important to identify synthetic and natural molecules able to impair the toxic effects of 7KC. We determined the impact of 7KC on murine microglial BV-2 cells, especially its ability to trigger mitochondrial and peroxisomal dysfunction, and evaluated the protective effects of α- and γ-tocopherol, Trolox, and oleic acid (OA). Multiple complementary chemical assays, flow cytometric and biochemical methods were used to evaluate the antioxidant and cytoprotective properties of these molecules. According to various complementary assays to estimate antioxidant activity, only α-, and γ-tocopherol, and Trolox had antioxidant properties. However, only α-tocopherol, γ-tocopherol and OA were able to impair 7KC-induced loss of mitochondrial transmembrane potential, which is associated with increased permeability to propidium iodide, an indicator of cell death. In addition, α-and γ-tocopherol, and OA were able to prevent the decrease in Abcd3 protein levels, which allows the measurement of peroxisomal mass, and in mRNA levels of Abcd1 and Abcd2, which encode for two transporters involved in peroxisomal β-oxidation. Thus, 7KC-induced side effects are associated with mitochondrial and peroxisomal dysfunction which can be inversed by natural compounds, thus supporting the hypothesis that the composition of the diet can act on the function of organelles involved in neurodegenerative diseases.
脂质过氧化产物，如7-酮胆固醇（7KC），在神经退行性疾病患者的体液和组织中可能会增加，并引发参与神经退行性变的小胶质细胞功能障碍。因此，识别能够削弱7KC毒性作用的合成和天然分子非常重要。我们确定了7KC对小鼠小胶质细胞BV-2的影响，特别是其引发线粒体和过氧化物酶体功能障碍的能力，并评估了α-生育酚、γ-生育酚、Trolox和油酸（OA）的保护作用。使用多种互补化学分析、流式细胞术和生化方法来评估这些分子的抗氧化和细胞保护特性。根据各种评估抗氧化活性的互补分析，只有α-生育酚、γ-生育酚和Trolox具有抗氧化特性。然而，只有α-生育酚、γ-生育酚和OA能够削弱7KC诱导的线粒体跨膜电位丧失，这与碘化丙啶通透性增加有关，碘化丙啶是细胞死亡的一个指标。此外，α-生育酚、γ-生育酚和OA能够防止参与过氧化物酶体β-氧化的两种转运蛋白编码的Abcd3蛋白水平以及Abcd1和Abcd2 mRNA水平的下降，Abcd3蛋白水平可用于测量过氧化物酶体质量。因此，7KC诱导的副作用与线粒体和过氧化物酶体功能障碍有关，天然化合物可以逆转这种功能障碍，从而支持饮食组成可作用于参与神经退行性疾病的细胞器功能这一假说。
