Glycosphingolipids are cell-type-specific components of the outer leaflet of mammalian plasma membranes. Gangliosides, sialic acid-containing glycosphingolipids, are especially enriched on neuronal surfaces. As amphi-philic molecules, they comprise a hydrophilic oligosaccharide chain attached to a hydrophobic membrane anchor, ceramide. Whereas glycosphingolipid formation is catalyzed by membrane-bound enzymes along the secretory pathway, degradation takes place at the surface of intralysosomal vesicles of late endosomes and lysosomes catalyzed in a stepwise fashion by soluble hydrolases and assisted by small lipid-binding glycoproteins. Inherited defects of lysosomal hydrolases or lipid-binding proteins cause the accumulation of undegradable material in lysosomal storage diseases (GM1 and GM2 gangliosidosis; Fabry, Gaucher, and Krabbe diseases; and metachromatic leukodystrophy). The catabolic processes are strongly modified by the lipid composition of the substrate-carrying membranes, and the pathological accumulation of primary storage compounds can trigger an accumulation of secondary storage compounds (e.g., small glycosphingolipids and cholesterol in Niemann-Pick disease).

中文翻译：

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溶酶体糖鞘脂贮积病。

糖鞘脂是哺乳动物质膜外小叶的细胞类型特异性成分。神经节苷脂（含唾液酸的糖鞘脂）在神经元表面特别丰富。作为两亲性分子，它们包含连接至疏水性膜锚，神经酰胺的亲水性寡糖链。糖鞘脂的形成是由沿着分泌途径的膜结合酶催化的，而降解发生在晚期内体的溶酶体囊泡表面，而溶酶体则通过可溶性水解酶逐步催化并由小脂质结合糖蛋白协助。溶酶体水解酶或脂质结合蛋白的遗传缺陷会导致溶酶体贮积病（GM1和GM2神经节病；法布里，高歇和克拉贝病；非霍奇金淋巴瘤）中不可降解物质的积累。和变色性脑白质营养不良）。分解代谢过程被底物携带膜的脂质组成强烈修饰，并且一级贮藏化合物的病理性积累可以触发二级贮藏化合物的积累（例如，尼曼-皮克病中的小鞘糖脂和胆固醇）。