Fas/FasL play a central role in pancreatitis-induced hepatocyte apoptosis.
Liver injury is a clinical prognostic indicator in acute pancreatitis (AP). We have demonstrated that Kupffer cell-derived FasL mediates liver injury during AP and sought to determine its role in AP-induced hepatocyte apoptosis. AP was induced in National Institutes of Health (NIH) Swiss mice, C57/C57, and Fas-/-, FasL-/- mice by a choline-deficient ethionine-supplement diet. Liver Fas, FasL, p38-mitogen activated phosphokinase (p38-MAPK), poly-ADP ribose polymerase (PARP), and cytochrome C were measured by immunoblotting. Apoptosis was assessed by terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) and DNA fragmentation (ELISA). AP upregulated liver FasL (4280 +/- 580 vs. 733 +/- 336), Fas (2866 +/- 595 vs. 649 +/- 111), cytochrome C (6980 +/- 237 vs. 903 +/- 156), and PARP (6393 +/- 591 vs. 466 +/- 261) as well as increased TUNEL staining (40 +/- 2 vs. 14 +/- 1) and DNA fragmentation (all P < 0.03 vs. control). In FasL-/- and Fas-/- mice, AP-induced upregulation of p38-MAPK, PARP, and cytochrome C was significantly attenuated (all P < 0.01 compared to C57/C57 control). In addition, AP-induced DNA fragmentation was reduced 60% in Fas-/- and FasL-/- mice (P < 0.01 vs. C57/C57). AP induces apoptosis by transcriptional activation of Fas/FasL. AP-induced apoptosis was significantly reduced in Fas and FasL knockout mice along with downregulation of p38-MAPK, PARP, and cytochrome C, thereby suggesting a central role for Fas/FasL in hepatocyte apoptosis. The manipulation of interactions between Kupffer cell-derived FasL and hepatocytes may have important therapeutic implications.
Gallagher
Scott F
SF
Departments of Surgery, James A. Haley Veterans Affairs Medical Center, University of South Florida Health Sciences Center, Tampa, Florida, USA.
Peng
Yanhua
Y
Haines
Krista
K
Baksh
Kathryn
K
Epling-Burnette
P K
PK
Yang
Jun
J
Murr
Michel M
MM
D000208:Acute Disease; D000818:Animals; D017209:Apoptosis; D015153:Blotting, Western; D045304:Cytochromes c / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D053222:Fas Ligand Protein; D005260:Female; D022781:Hepatocytes / Q000378:metabolism*; D020287:In Situ Nick-End Labeling; D007728:Kupffer Cells / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D010195:Pancreatitis / Q000378:metabolism / Q000503:physiopathology*; D018124:Receptors, Tumor Necrosis Factor / Q000378:metabolism*; D015854:Up-Regulation; D019014:fas Receptor; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
D053222:Fas Ligand Protein; C491899:Fas protein, mouse; C505658:Fasl protein, mouse; D008562:Membrane Glycoproteins; D018124:Receptors, Tumor Necrosis Factor; D019014:fas Receptor; D045304:Cytochromes c; D048051:p38 Mitogen-Activated Protein Kinases