Expression of DNase gamma during Fas-independent apoptotic DNA fragmentation in rodent hepatocytes.
Endonuclease-induced DNA fragmentation is a hallmark of apoptosis. DNase gamma (DNase gamma) was recently identified as one of the endonucleases responsible for apoptotic DNA fragmentation. In this study, immunohistochemistry for DNase gamma was performed on paraffin sections of rodent liver in well-defined models of hepatocyte apoptosis induced by Fas antibody (Fas) or cycloheximide (CHX), and necrosis induced by lipopolysaccharide (LPS) or carbon tetrachloride (CCl4). DNase gamma immunoreactivity was compared with TdT-mediated dUTP nick-end labeling (TUNEL) reactivity. Our results showed TUNEL reactivity in both apoptotic and necrotic hepatocytes. DNase gamma immunoreactivity was not detected during LPS-induced or CCl4-induced hepatocyte necrosis. In contrast, it was evident during CHX-induced, but not Fas-induced, apoptotic DNA fragmentation. These findings suggest that DNase gamma plays an important role in Fas-independent apoptotic DNA fragmentation in hepatocytes.
Higami
Yoshikazu
Y
Department of Pathology and Gerontology, Nagasaki University Graduate School of Biomedical Science, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan. higami@net.nagasaki-u.ac.jp
Tsuchiya
Tomoshi
T
To
Kazuo
K
Chiba
Takuya
T
Yamaza
Haruyoshi
H
Shiokawa
Daisuke
D
Tanuma
Sei-ichi
S
Shimokawa
Isao
I
D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D002251:Carbon Tetrachloride; D053938:DNA Fragmentation / Q000187:drug effects / Q000235:genetics*; D004706:Endodeoxyribonucleases / Q000378:metabolism*; D022781:Hepatocytes / Q000187:drug effects / Q000201:enzymology*; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D008070:Lipopolysaccharides; D008099:Liver / Q000201:enzymology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009336:Necrosis / Q000139:chemically induced / Q000201:enzymology / Q000503:physiopathology; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D051381:Rats; D011916:Rats, Inbred F344; D019014:fas Receptor / Q000378:metabolism*
D000906:Antibodies; D008070:Lipopolysaccharides; D011500:Protein Synthesis Inhibitors; D019014:fas Receptor; D002251:Carbon Tetrachloride; D004706:Endodeoxyribonucleases; C105124:deoxyribonuclease gamma