Article

Hepatoprotective role of endogenous interleukin-13 in a murine model of acetaminophen-induced liver disease

Molecular and Cellular Toxicology Section, Laboratory of Molecular Immunology, National Heart, Lung, and Blood Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland 20892, USA.
Chemical Research in Toxicology (Impact Factor: 4.19). 06/2007; 20(5):734-44. DOI: 10.1021/tx600349f
Source: PubMed

ABSTRACT Recent evidence suggests that a deficiency in one or more hepatoprotective regulatory mechanisms may contribute to determining susceptibility in drug-induced liver disease. In the present study, we investigated the role of interleukin (IL)-13 in acetaminophen (APAP)-induced liver disease (AILD). Following APAP (200 mg/kg) administration to male C57BL/6 wild-type (WT) mice, hepatotoxicity developed up to 24 h post-APAP, with a concomitant increase in serum IL-13 concentration. Pretreatment of these mice with an IL-13-neutralizing antibody exacerbated liver injury, as did APAP administration to IL-13 knockout (KO) mice in comparison to WT mice. No difference was observed in either overall APAP-protein adduct formation or liver glutathione levels between KO and WT mice following APAP administration, suggesting that the increased susceptibility of IL-13 KO mice to AILD was not due to enhanced APAP bioactivation but rather injurious downstream events. In this regard, multiplex antibody arrays were used to identify potential IL-13-regulated biomarkers, including various cytokines and chemokines, as well as nitric oxide (NO), associated with AILD that were present at higher concentrations in the sera of APAP-treated IL-13 KO mice than in WT mice. Subsequent inhibition studies determined interferon-gamma, NO, neutrophils, natural killer cells, and natural killer cells with T-cell receptors had pathologic roles in AILD in IL-13 KO mice. Taken together, these results suggest that IL-13 is a critical hepatoprotective factor modulating the susceptibility to AILD and may provide hepatoprotection, in part, by down-regulating protoxicant factors and cells associated with the innate immune system.

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