title: Ceramide generation by two distinct pathways in tumor necrosis factor alpha-induced cell death.
abstract: Ceramide accumulation in the cell can occur from either hydrolysis of sphingomyelin or by de novo synthesis. In this study, we found that blocking de novo ceramide synthesis significantly inhibits ceramide accumulation and subsequent cell death in response to tumor necrosis factor alpha. When cells were pre-treated with glutathione, a proposed cellular regulator of neutral sphingomyelinase, inhibition of ceramide accumulation at early time points was achieved with attenuation of cell death. Inhibition of both pathways achieved near-complete inhibition of ceramide accumulation and cell death indicating that both pathways of ceramide generation are stimulated. This illustrates the complexity of ceramide generation in cytokine action.
authors.affiliation: Department of Pediatrics, American University of Beirut, Lebanon. gdbaibo@aub.edu.lb
authors.forename: G S
authors.initials: GS
authors.lastname: Dbaibo
authors.forename: W
authors.initials: W
authors.lastname: El-Assaad
authors.forename: A
authors.initials: A
authors.lastname: Krikorian
authors.forename: B
authors.initials: B
authors.lastname: Liu
authors.forename: K
authors.initials: K
authors.lastname: Diab
authors.forename: N Z
authors.initials: NZ
authors.lastname: Idriss
authors.forename: M
authors.initials: M
authors.lastname: El-Sabban
authors.forename: T A
authors.initials: TA
authors.lastname: Driscoll
authors.forename: D K
authors.initials: DK
authors.lastname: Perry
authors.forename: Y A
authors.initials: YA
authors.lastname: Hannun
mesh_terms: D017209:Apoptosis / Q000502:physiology*; D002518:Ceramides / Q000096:biosynthesis*; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism* / Q000502:physiology
chemical_list: D002518:Ceramides; D014409:Tumor Necrosis Factor-alpha; D005978:Glutathione