Effects of an inhibitor of glucosylceramide synthase on glycosphingolipid synthesis and neurite outgrowth in murine neuroblastoma cell lines.
1-Phenyl-2-decanolyamino-3-morpholino-1-propanol (PDMP), an effective inhibitor of UDP-glucose:ceramide glucosyltransferase, caused inhibition of cell growth in murine neuroblastoma cell lines. Metabolic labeling of glycosphingolipids with [14C]galactose in NS-20Y, Neuro2a, and N1E-115 cells showed reduced incorporation of radioactivity into gangliosides and neutral glycosphingolipids when threo-PDMP was present in the medium. Treatment of NS-20Y cells with threo-PDMP resulted in a time-dependent decrease in mass levels of gangliosides and neutral glycosphingolipids. After 24 h in the presence of 50 microM threo-PDMP, neutral glycosphingolipid mass was reduced to 32%, where glucosylceramide was the most affected (90% decrease). The ganglioside mass was reduced to 57% of the original content. Neurite outgrowth from neuroblastoma cells in serum-free medium was significantly inhibited by threo-PDMP in a dose-dependent manner. Threo-PDMP also caused retraction of neurites which had been induced to extend in serum-free medium. Pretreatment of cells with GM1 partially restored the ability of NS-20Y cells for neurite outgrowth in the medium containing threo-PDMP. These results suggest a possible role for glycosphingolipids in neurite outgrowth of murine neuroblastoma cells.
Uemura
K
K
Department of Lipid Biochemistry, Shinshu University School of Medicine, Nagano.
Sugiyama
E
E
Taketomi
T
T
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D005964:Glucosyltransferases / Q000037:antagonists & inhibitors*; D006028:Glycosphingolipids / Q000096:biosynthesis*; D051379:Mice; D009025:Morpholines / Q000494:pharmacology*; D016501:Neurites / Q000187:drug effects* / Q000648:ultrastructure; D009447:Neuroblastoma / Q000378:metabolism / Q000648:ultrastructure; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure
D006028:Glycosphingolipids; D009025:Morpholines; C033110:RV 538; D005964:Glucosyltransferases; C023246:ceramide glucosyltransferase