Effects of nuclear translocation of tissue transglutaminase and the release of cytochrome C on hepatocyte apoptosis / 中华医学杂志(英文版)
Chinese Medical Journal
; (24): 742-746, 2003.
Article
in English
| WPRIM (Western Pacific)
| ID: wpr-324420
Responsible library:
WPRO
ABSTRACT
<p><b>OBJECTIVE</b>To assess the effects of nuclear translocation of tissue transglutaminase (TTG) and the release of cytochrome C on hepatocyte apoptosis and to reveal the mechanism of signal transduction of early apoptosis in injured hepatocytes.</p><p><b>METHODS</b>Hepatocytes isolated from tissue transglutaminase gene knock-out mice and rats were stimulated with ethanol. Proteins from whole cell, cytoplasm and nuclei were extracted for determination of TTG activity by (14)C-putrescine incorporation. Distribution of TTG throughout the entire cell, as well as just nucleus was observed under a confocal scanning microscope. The amount of cytochrome C released from mitochondria was determined by ELISA. Cell apoptosis was observed by fluorescent cytochemistry.</p><p><b>RESULTS</b>TTG activity in whole cells and nuclei was significantly increased after the hepatocytes were treated with ethanol. Cytochrome C release was remarkably increased in the cells isolated from rat and wild-type mouse after treatment with ethanol but not in TTG gene knock-out mice. Cellular apoptosis appeared in hepatocytes isolated from rats and wild-type mice but not in the hepatocytes from TTG gene knock-out mice after stimulation with ethanol.</p><p><b>CONCLUSIONS</b>Increased TTG in hepatocytes can be translocated into the nucleus and promote release of mitochondrial cytochrome C into the cytoplasm. Passing through a series of signal pathways, hepatocyte apoptosis is induced eventually.</p>
Full text:
Available
Database:
WPRIM (Western Pacific)
Main subject:
Signal Transduction
/
Cell Nucleus
/
Transglutaminases
/
Apoptosis
/
Hepatocytes
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Cytochrome c Group
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Cell Biology
/
Metabolism
Limits:
Animals
Language:
English
Journal:
Chinese Medical Journal
Year:
2003
Document type:
Article