Short-chain 3-ketoceramides, strong apoptosis inducers against human leukemia HL-60 cells.
Ceramides act as a second messenger of the apoptotic signaling process. The allylic alcohol portion comprising the C-3, C-4, and C-5 carbons is essential for this function. The suggestion has been made that this alcohol moiety is oxidized in mitochondria to a carbonyl moiety, with the generation of reactive oxygen species. However, there is no established precedent for the apoptotic performance of 3-ketoceramides thus presumed. In this work, we have synthesized three different types of short-chain 3-ketoceramides, that is, (2S,4E)-2-acetylamino-3-oxo-4-octadecen-1-ol (A), (2S,4E,6E)-2-acetylamino-3-oxo-4,6-octadecadien-1-ol (B), and (2S,4E)-2-acetylamino-1-methoxy-3-oxo-4-octadecene (C), and demonstrated that these 3-ketoceramides are capable of inducing effective apoptosis in human leukemia HL-60 cells. In particular, the two monoenoic compounds, A and C, are far more powerful than the corresponding alcoholic analogue, N-acetyl-D-erythro-sphingosine. Observations of DNA fragmentation, caspase-3 activation, and cytochrome c release from mitochondria provide substantiated evidence for mitochondrial apoptosis and the effects of exogenous glutathione on these phenomena are also discussed.
Azuma
Hideki
H
Department of Applied and Bioapplied Chemistry, Graduate School of Engineering, Osaka City University, Sugimoto 3-3-138, Sumiyoshi-ku, Osaka 558 8585, Japan. azumah@bioa.eng.osaka-cu.ac.jp
Ijichi
So
S
Kataoka
Mayuko
M
Masuda
Akira
A
Izumi
Takayuki
T
Yoshimoto
Tetsuya
T
Tachibana
Taro
T
D000970:Antineoplastic Agents / Q000138:chemical synthesis* / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D045744:Cell Line, Tumor; D002518:Ceramides / Q000138:chemical synthesis* / Q000494:pharmacology*; D045304:Cytochromes c / Q000378:metabolism; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D053938:DNA Fragmentation / Q000187:drug effects; D004789:Enzyme Activation / Q000187:drug effects; D005978:Glutathione / Q000494:pharmacology; D018922:HL-60 Cells; D006801:Humans; D015151:Immunoblotting; D007202:Indicators and Reagents; D008928:Mitochondria / Q000187:drug effects / Q000201:enzymology; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D013056:Spectrophotometry, Ultraviolet; D013778:Tetrazolium Salts; D013844:Thiazoles
D000970:Antineoplastic Agents; D002518:Ceramides; D007202:Indicators and Reagents; D017382:Reactive Oxygen Species; D013778:Tetrazolium Salts; D013844:Thiazoles; D045304:Cytochromes c; D053148:Caspase 3; C022616:thiazolyl blue; D005978:Glutathione