Department of Neurological, Psychological, Morphological and Motor Sciences, Divisions of Neurology (Child Neurology) and Neuropathology, University of Verona Medical School, Verona, Italy.
Biochem Biophys Res Commun. 2011 Dec 9;416(1-2):159-64. doi: 10.1016/j.bbrc.2011.11.016. Epub 2011 Nov 11.
Neuronal ceroid lipofuscinosis (NCL) are a group of progressive neurodegenerative disorders of childhood, characterized by the endo-lysosomal storage of autofluorescent material. Impaired mitochondrial function is often associated with neurodegeneration, possibly related to the apoptotic cascade. In this study we investigated the possible effects of lysosomal accumulation on the mitochondrial compartment in the fibroblasts of two NCL forms, CLN1 and CLN6. Fragmented mitochondrial reticulum was observed in all cells by using the intravital fluorescent marker Mitotracker, mainly in the perinuclear region. This was also associated with intense signal from the lysosomal markers Lysotracker and LAMP2. Likewise, mitochondria appeared to be reduced in number and shifted to the cell periphery by electron microscopy; moreover the mitochondrial markers VDCA and COX IV were reduced following quantitative Western blot analysis. Whilst there was no evidence of increased cell death under basal condition, we observed a significant increase in apoptotic nuclei following Staurosporine treatment in CLN1 cells only. In conclusion, the mitochondrial compartment is affected in NCL fibroblasts invitro, and CLN1 cells seem to be more vulnerable to the negative effects of stressed mitochondrial membrane than CLN6 cells.
神经元蜡样脂褐质沉积症（NCL）是一组儿童进行性神经退行性疾病，其特征是内溶酶体储存自发荧光物质。线粒体功能障碍常与神经退行性变有关，可能与细胞凋亡级联有关。在这项研究中，我们研究了溶酶体积累对两种 NCL 形式（CLN1 和 CLN6）成纤维细胞中线粒体区室的可能影响。使用活体荧光标记物 Mitotracker 观察到所有细胞中的线粒体网呈片段化，主要在核周区域。这也与溶酶体标记物 Lysotracker 和 LAMP2 的强烈信号相关。同样，电子显微镜显示线粒体数量减少，并向细胞边缘转移；此外，定量 Western blot 分析显示线粒体标记物 VDCA 和 COX IV 减少。虽然在基础条件下没有证据表明细胞死亡增加，但我们观察到在用 Staurosporine 处理 CLN1 细胞后，凋亡核显著增加。总之，NCL 成纤维细胞中的线粒体区室受到影响，并且 CLN1 细胞似乎比 CLN6 细胞更容易受到应激线粒体膜的负面影响。
