Transforming growth factor beta1 attenuates ceramide-induced CPP32/Yama activation and apoptosis in human leukaemic HL-60 cells.
Ceramide, a product of sphingomyelin turnover, is a novel lipid second messenger that mediates important cellular functions including proliferation, differentiation and apoptosis. This study demonstrates that the CPP32/Yama protease was activated during apoptosis induced by the membrane-permeable second messenger C2-ceramide in HL-60 cells. We also found that the addition of a specific tetrapeptide inhibitor of CPP32/Yama, Ac-DEVD-CHO, provided an effective protection against ceramide-induced cell death. These results suggested that CPP32/Yama has a central role in ceramide-mediated apoptosis. Furthermore a wide variety of cytokines were examined for their effect on ceramide-induced apoptosis. Only transforming growth factor beta1 (TGF-beta1) (1 ng/ml) exerted significant prevention of apoptosis induced by C2-ceramide, or by sphingomyelinase (increases intracellular ceramide). Consistently, TGF-beta1 abrogated the cleavage of poly(ADP-ribose) polymerase and the production of the CPP32/Yama active subunit, p17. However, TGF-beta1 treatment did not cause growth inhibition or alter the level of cyclin-dependent kinase inhibitor p27. It suggests that the preventive effect of TGF-beta1 is not mediated by growth arrest. Interestingly, we found that TGF-beta1 prevented the C2-ceramide-caused decrease of Bcl-2 protein. We thus propose that TGF-beta1 rescues ceramide-induced cell death, possibly by maintaining the constant level of Bcl-2, thereby abolishing CPP32/Yama protease activation.
Kuo
M L
ML
Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan.
Chen
C W
CW
Jee
S H
SH
Chuang
S E
SE
Cheng
A L
AL
D017209:Apoptosis / Q000187:drug effects; D053148:Caspase 3; D020169:Caspases; D018797:Cell Cycle Proteins; D002518:Ceramides / Q000378:metabolism* / Q000494:pharmacology; D050760:Cyclin-Dependent Kinase Inhibitor p27; D018844:Cyclin-Dependent Kinases / Q000037:antagonists & inhibitors; D003546:Cysteine Endopeptidases / Q000378:metabolism*; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D004789:Enzyme Activation; D018922:HL-60 Cells; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D009842:Oligopeptides / Q000494:pharmacology; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis; D013108:Sphingomyelin Phosphodiesterase / Q000378:metabolism; D013110:Sphingosine / Q000031:analogs & derivatives / Q000378:metabolism / Q000494:pharmacology; D016212:Transforming Growth Factor beta / Q000378:metabolism*; D025521:Tumor Suppressor Proteins
D018797:Cell Cycle Proteins; D002518:Ceramides; D015853:Cysteine Proteinase Inhibitors; D008869:Microtubule-Associated Proteins; C064769:N-acetylsphingosine; D009842:Oligopeptides; D019253:Proto-Oncogene Proteins c-bcl-2; D016212:Transforming Growth Factor beta; D025521:Tumor Suppressor Proteins; C099158:acetyl-aspartyl-glutamyl-valyl-aspartal; D050760:Cyclin-Dependent Kinase Inhibitor p27; D011065:Poly(ADP-ribose) Polymerases; D018844:Cyclin-Dependent Kinases; D013108:Sphingomyelin Phosphodiesterase; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases; D003546:Cysteine Endopeptidases; D013110:Sphingosine