Biomaterial Database

Role of the ceramide-signaling pathways in ionizing radiation-induced apoptosis. 2003

Jean-Philippe Vit, and Filippo Rosselli

1UPR 2169 CNRS, Institut Gustave Roussy IFR 54, 39 rue Camille Desmoulins, 94805 Villejuif Cedex, France.

Ionizing radiations (IR) exposure leads to damage on several cellular targets. How signals from different targets are integrated to determine the cell fate remains a controversial issue. Understanding the pathway(s) responsible(s) for the cell killing effect of the IR exposure is of prime importance in light of using radiations as anticancer agent or as diagnostic tool. In this study, we have established that IR-induced cell damage initiates two independent signaling pathways that lead to a biphasic intracellular ceramide increase. A transitory increase of ceramide is observed within minutes after IR exposure as a consequence of DNA damage-independent acid sphingomyelinase activation. Several hours after irradiation, a second wave of ceramide accumulation is observed depending on the DNA damage-dependent activation of ceramide synthase, which requires a signaling pathway involving ATM. Importantly, we have demonstrated that the late ceramide accumulation is also dependent on the first one and is rate limiting for the apoptotic process induced by IR. In conclusion, our observations suggest that ceramide is a major determinant of the IR-induced apoptotic process at the cross-point of different signal transduction pathways.

UI	MeSH Term	Description	Entries
D009542	Niemann-Pick Diseases	A group of autosomal recessive disorders in which harmful quantities of lipids accumulate in the viscera and the central nervous system. They can be caused by deficiencies of enzyme activities (SPHINGOMYELIN PHOSPHODIESTERASE) or defects in intracellular transport, resulting in the accumulation of SPHINGOMYELINS and CHOLESTEROL. There are various subtypes based on their clinical and genetic differences.	ASM Deficiency,ASM-Deficient Niemann-Pick Disease,Acid Sphingomyelinase Deficiency,Acid Sphingomyelinase-deficient Niemann-Pick Disease,Niemann-Pick Disease,ASM Deficiencies,ASM Deficient Niemann Pick Disease,ASM-Deficient Niemann-Pick Diseases,Acid Sphingomyelinase deficient Niemann Pick Disease,Deficiencies, ASM,Deficiencies, Acid Sphingomyelinase,Deficiency, ASM,Deficiency, Acid Sphingomyelinase,Disease, ASM-Deficient Niemann-Pick,Diseases, ASM-Deficient Niemann-Pick,Niemann Pick Disease,Niemann Pick Diseases,Niemann-Pick Disease, ASM-Deficient,Niemann-Pick Diseases, ASM-Deficient,Sphingomyelinase Deficiencies, Acid,Sphingomyelinase Deficiency, Acid
D010088	Oxidoreductases	The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)	Dehydrogenases,Oxidases,Oxidoreductase,Reductases,Dehydrogenase,Oxidase,Reductase
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D002518	Ceramides	Members of the class of neutral glycosphingolipids. They are the basic units of SPHINGOLIPIDS. They are sphingoids attached via their amino groups to a long chain fatty acyl group. They abnormally accumulate in FABRY DISEASE.	Ceramide
D004249	DNA Damage	Injuries to DNA that introduce deviations from its normal, intact structure and which may, if left unrepaired, result in a MUTATION or a block of DNA REPLICATION. These deviations may be caused by physical or chemical agents and occur by natural or unnatural, introduced circumstances. They include the introduction of illegitimate bases during replication or by deamination or other modification of bases; the loss of a base from the DNA backbone leaving an abasic site; single-strand breaks; double strand breaks; and intrastrand (PYRIMIDINE DIMERS) or interstrand crosslinking. Damage can often be repaired (DNA REPAIR). If the damage is extensive, it can induce APOPTOSIS.	DNA Injury,DNA Lesion,DNA Lesions,Genotoxic Stress,Stress, Genotoxic,Injury, DNA,DNA Injuries
D004268	DNA-Binding Proteins	Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.	DNA Helix Destabilizing Proteins,DNA-Binding Protein,Single-Stranded DNA Binding Proteins,DNA Binding Protein,DNA Single-Stranded Binding Protein,SS DNA BP,Single-Stranded DNA-Binding Protein,Binding Protein, DNA,DNA Binding Proteins,DNA Single Stranded Binding Protein,DNA-Binding Protein, Single-Stranded,Protein, DNA-Binding,Single Stranded DNA Binding Protein,Single Stranded DNA Binding Proteins
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D015398	Signal Transduction	The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.	Cell Signaling,Receptor-Mediated Signal Transduction,Signal Pathways,Receptor Mediated Signal Transduction,Signal Transduction Pathways,Signal Transduction Systems,Pathway, Signal,Pathway, Signal Transduction,Pathways, Signal,Pathways, Signal Transduction,Receptor-Mediated Signal Transductions,Signal Pathway,Signal Transduction Pathway,Signal Transduction System,Signal Transduction, Receptor-Mediated,Signal Transductions,Signal Transductions, Receptor-Mediated,System, Signal Transduction,Systems, Signal Transduction,Transduction, Signal,Transductions, Signal
D017209	Apoptosis	A regulated cell death mechanism characterized by distinctive morphologic changes in the nucleus and cytoplasm, including the endonucleolytic cleavage of genomic DNA, at regularly spaced, internucleosomal sites, i.e., DNA FRAGMENTATION. It is genetically programmed and serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.	Apoptosis, Extrinsic Pathway,Apoptosis, Intrinsic Pathway,Caspase-Dependent Apoptosis,Classic Apoptosis,Classical Apoptosis,Programmed Cell Death,Programmed Cell Death, Type I,Apoptoses, Extrinsic Pathway,Apoptoses, Intrinsic Pathway,Apoptosis, Caspase-Dependent,Apoptosis, Classic,Apoptosis, Classical,Caspase Dependent Apoptosis,Cell Death, Programmed,Classic Apoptoses,Extrinsic Pathway Apoptoses,Extrinsic Pathway Apoptosis,Intrinsic Pathway Apoptoses,Intrinsic Pathway Apoptosis
D017346	Protein Serine-Threonine Kinases	A group of enzymes that catalyzes the phosphorylation of serine or threonine residues in proteins, with ATP or other nucleotides as phosphate donors.	Protein-Serine-Threonine Kinases,Serine-Threonine Protein Kinase,Serine-Threonine Protein Kinases,Protein-Serine Kinase,Protein-Serine-Threonine Kinase,Protein-Threonine Kinase,Serine Kinase,Serine-Threonine Kinase,Serine-Threonine Kinases,Threonine Kinase,Kinase, Protein-Serine,Kinase, Protein-Serine-Threonine,Kinase, Protein-Threonine,Kinase, Serine-Threonine,Kinases, Protein Serine-Threonine,Kinases, Protein-Serine-Threonine,Kinases, Serine-Threonine,Protein Kinase, Serine-Threonine,Protein Kinases, Serine-Threonine,Protein Serine Kinase,Protein Serine Threonine Kinase,Protein Serine Threonine Kinases,Protein Threonine Kinase,Serine Threonine Kinase,Serine Threonine Kinases,Serine Threonine Protein Kinase,Serine Threonine Protein Kinases