Mancini G M, Hoogeveen A T, Galjaard H, Mansson J E, Svennerholm L
Hum Genet. 1986 May;73(1):35-8. doi: 10.1007/BF00292661.
The uptake and catabolism of [3H-ceramide]-GM1 was followed in living fibroblasts from patient with different forms of beta-galactosidase deficiency. Gangliosides are identified according to the nomenclature of Svennerholm (1963). A total inability to metabolize the ingested substrate was found in infantile GM1-gangliosidosis whereas cells from an adult GM1-gangliosidosis variant showed a slower rate of degradation, compared with controls. Morquio B fibroblasts had a comparable catabolism of GM1 as controls. Fibroblasts from different types of galactosialidosis, a recessive disease associated with a coexistent beta-galactosidase/neuraminidase deficiency all showed degradation of ingested GM1. In view of the molecular defect in this disease, this catabolism must be due to the 10-20% of monomeric beta-galactosidase molecules present in the lysosomes. Unexpectedly, in these cells an impaired metabolism of GM3 was found. The same finding was observed when cells with an isolated neuraminidase deficiency (mucolipidosis I) were loaded with GM1. A hypothesis is presented to explain these results.
在患有不同形式β-半乳糖苷酶缺乏症患者的活成纤维细胞中，追踪了[³H-神经酰胺]-GM1的摄取和分解代谢。神经节苷脂根据斯文内霍尔姆（1963年）的命名法进行鉴定。在婴儿型GM1-神经节苷脂沉积症中发现完全无法代谢摄入的底物，而与对照组相比，来自成人GM1-神经节苷脂沉积症变体的细胞显示出较慢的降解速率。莫尔基奥B型成纤维细胞对GM1的分解代谢与对照组相当。来自不同类型半乳糖唾液酸沉积症（一种与共存的β-半乳糖苷酶/神经氨酸酶缺乏相关的隐性疾病）的成纤维细胞均显示摄入的GM1有降解。鉴于该疾病的分子缺陷，这种分解代谢必定归因于存在于溶酶体中的10%-20%的单体β-半乳糖苷酶分子。出乎意料的是，在这些细胞中发现GM3的代谢受损。当用GM1加载具有孤立神经氨酸酶缺乏症（粘脂贮积症I型）的细胞时，也观察到了相同的发现。本文提出了一个假说来解释这些结果。
