Effects of dimethylsulfoxide on sphingomyelinase activities in normal and Niemann-Pick type A, B and C fibroblasts.

Abstract

The effects of dimethylsulfoxide (DMSO) on sphingomyelinase activity measured at pH range 3.5-8.0 were examined in normal and Niemann-Pick disease type A, B and C fibroblasts culture. In normal cells, a minor activity was observed at pH 7.5, which was 3- to 4-fold lower than a major one at pH 5.0. Both activities at pH 5.0 and 7.5 were Mg2+-independent and localized to lysosomes. Niemann-Pick type C cells had 30-50% residual sphingomyelinase activity at both pH 5.0 and 7.5, as compared to normal control cells, whereas type A and B cells exhibited virtually no activity over the entire pH range examined. Treatment with 2% DMSO caused a marked increase in sphingomyelinase activities at pH 5.0 and 7.5 in normal and Niemann-Pick disease type C cells, while in type A and B cells, both activities remained virtually unchanged after DMSO treatment. The increase in sphingomyelinase activity at pH 5.0 induced in normal cells by DMSO resulted in an increase in the Vmax without a substantial change in the Km and was inhibited by the simultaneous addition of 10 micrograms/ml of cycloheximide. By comparison, a less than 2-fold increase in other lysosomal hydrolase activities was observed after DMSO treatment in all cell lines examined.

• Authors: M Sato, Y Yoshida, N Sakuragawa, M Arima
• Journal: Biochimica et biophysica acta (Biochim Biophys Acta) Vol. 962 Issue 1 Pg. 59-65 (Sep 02 1988) ISSN: 0006-3002 [Print] Netherlands
• PMID: 2843241 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Cycloheximide
• Phosphoric Diester Hydrolases
• Sphingomyelin Phosphodiesterase
• Dimethyl Sulfoxide

Topics

• Cell Line
• Cycloheximide (pharmacology)
• Dimethyl Sulfoxide (pharmacology)
• Enzyme Activation (drug effects)
• Fibroblasts (drug effects, enzymology, pathology)
• Humans
• Hydrogen-Ion Concentration
• Intracellular Fluid (drug effects, enzymology)
• Lysosomes (drug effects, enzymology)
• Niemann-Pick Diseases (classification, enzymology, pathology)
• Phosphoric Diester Hydrolases (metabolism)
• Sphingomyelin Phosphodiesterase (antagonists & inhibitors, metabolism)