title: Pathophysiological role of the acute inflammatory response during acetaminophen hepatotoxicity.
abstract: Neutrophils are recruited into the liver after acetaminophen (AAP) overdose but the pathophysiological relevance of this acute inflammatory response remains unclear. To address this question, we compared the time course of liver injury, hepatic neutrophil accumulation and inflammatory gene mRNA expression for up to 24 h after treatment with 300 mg/kg AAP in C3Heb/FeJ and C57BL/6 mice. Although there was no relevant difference in liver injury (assessed by the increase of plasma alanine aminotransferase activities and the areas of necrosis), the number of neutrophils and the expression of several pro-inflammatory genes (e.g., tumor necrosis factor-alpha, interleukin-1beta and macrophage inflammatory protein-2) was higher in C3Heb/FeJ than in C57BL/6 mice. In contrast, the expression of the anti-inflammatory genes interleukin-10 and heme oxygenase-1 was higher in C57BL/6 mice. Despite substantial hepatic neutrophil accumulation, none of the liver sections from both strains stained positive for hypochlorite-modified proteins, a specific marker for a neutrophil-induced oxidant stress. In addition, treatment with the NADPH oxidase inhibitors diphenyleneiodonium chloride or apocynin or the anti-neutrophil antibody Gr-1 did not protect against AAP hepatotoxicity. Furthermore, although intercellular adhesion molecule-1 (ICAM-1) was previously shown to be important for neutrophil extravasation and tissue injury in several models, ICAM-1-deficient mice were not protected against AAP-mediated liver injury. Together, these data do not support the hypothesis that neutrophils aggravate liver injury induced by AAP overdose.
authors.affiliation: Liver Research Institute, University of Arizona, Tucson, AZ 85724, USA.
authors.forename: Cathleen
authors.initials: C
authors.lastname: Cover
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.forename: Anwar
authors.initials: A
authors.lastname: Farhood
authors.forename: Ernst
authors.initials: E
authors.lastname: Malle
authors.forename: Michael P
authors.initials: MP
authors.lastname: Waalkes
authors.forename: Mary Lynn
authors.initials: ML
authors.lastname: Bajt
authors.forename: Hartmut
authors.initials: H
authors.lastname: Jaeschke
mesh_terms: D000082:Acetaminophen / Q000633:toxicity*; D000208:Acute Disease; D000410:Alanine Transaminase / Q000097:blood; D018712:Analgesics, Non-Narcotic / Q000633:toxicity; D000818:Animals; D056486:Chemical and Drug Induced Liver Injury / Q000097:blood / Q000209:etiology / Q000503:physiopathology*; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D007249:Inflammation / Q000139:chemically induced / Q000235:genetics / Q000503:physiopathology*; D018799:Intercellular Adhesion Molecule-1 / Q000235:genetics; D053583:Interleukin-1beta / Q000235:genetics; D008099:Liver / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D020556:Neutrophil Infiltration / Q000187:drug effects; D000071137:Poly (ADP-Ribose) Polymerase-1; D011064:Poly Adenosine Diphosphate Ribose / Q000378:metabolism; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013045:Species Specificity; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics
chemical_list: D018712:Analgesics, Non-Narcotic; C090509:Icam1 protein, mouse; D053583:Interleukin-1beta; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D018799:Intercellular Adhesion Molecule-1; D011064:Poly Adenosine Diphosphate Ribose; D000082:Acetaminophen; C499321:Parp1 protein, mouse; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases; D000410:Alanine Transaminase