期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1990
卷号:87
期号:9
页码:3493-3497
DOI:10.1073/pnas.87.9.3493
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Saposins (A, B, C, and D) are small glycoproteins required for the hydrolysis of sphingolipids by specific lysosomal hydrolases. Concentrations of these saposins in brain, liver, and spleen from normal humans as well as patients with lysosomal storage disease were determined. A quantitative HPLC method was used for saposin A, C, and D and a stimulation assay was used for saposin B. In normal tissues, saposin D was the most abundant of the four saposins. Massive accumulations of saposins, especially saposin A (about 80-fold increase over normal), were found in brain of patients with Tay-Sachs disease or infantile Sandhoff disease. In spleen of adult patients with Gaucher disease, saposin A and D accumulations (60- and 17-fold, respectively, over normal) were higher than that of saposin C (about 16-fold over normal). Similar massive accumulations of saposins A and D were found in liver of patients with fucosidosis (about 70- and 20-fold, respectively, over normal). Saposin D was the primary saposin stored in the liver of a patient with Niemann-Pick disease (about 30-fold over normal). Moderate increases of saposins B and D were found in a patient with GM1 gangliosidosis. Normal or near normal levels of all saposins were found in patients with Krabbe disease, metachromatic leukodystrophy, Fabry disease, adrenoleukodystrophy, I-cell disease, mucopolysaccharidosis types 2 and 3B, or Jansky-Bielschowsky disease. The implications of the storage of saposins in these diseases are discussed.