3-Ketosphinganine provokes the accumulation of dihydroshingolipids and induces autophagy in cancer cells.

Although several reports describe the metabolic fate of sphingoid bases and their analogs, as well as their action and that of their phosphates as regulators of sphingolipid metabolizing-enzymes, similar studies for 3-ketosphinganine (KSa), the product of the first committed step in de novo sphingol...

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Detalhes bibliográficos
Autores: Ordóñez, Yadira F., González, Jèssica, Bedia, Carmen, Casas, Josefina, Abad, José Luis, Delgado Cirilo, Antonio, Fabriàs, Gemma
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2016
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositório:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/130514
Acesso em linha:http://hdl.handle.net/10261/130514
Access Level:Acceso aberto
Palavra-chave:Metabolic fate
3-ketosphinganine
KSa
Enzyme inhibition
Dihydroceramide metabolites
Descrição
Resumo:Although several reports describe the metabolic fate of sphingoid bases and their analogs, as well as their action and that of their phosphates as regulators of sphingolipid metabolizing-enzymes, similar studies for 3-ketosphinganine (KSa), the product of the first committed step in de novo sphingolipid biosynthesis, have not been reported. In this article we show that 3-ketosphinganine (KSa) and its dideuterated analog at C4 (d2KSa) are metabolized to produce high levels of dihydrosphingolipids in HGC27, T98G and U87MG cancer cells. In contrast, either direct C1 O-phosphorylation or N-acylation of d2KSa to produce dideuterated ketodihydrosphingolipids does not occur. We also show that cells respond to d2KSa treatment with induction of autophagy. Time-course experiments agree with sphinganine, sphinganine 1-phosphate and dihydroceramides being the mediators of autophagy stimulated by d2KSa. Enzyme inhibition studies support that inhibition of Des1 by 3-ketobases is caused by their dihydroceramide metabolites. However, this effect contributes to increasing dihydrosphingolipid levels only at short incubation times, since cells respond to long time exposure to 3-ketobases with Des1 overexpression. The translation of these overall effects into cell fate is discussed.