Toll Like Receptor 3 Plays a Critical Role in the Progression and Severity of Acetaminophen-Induced Hepatotoxicity

作者：Cavassani Karen A^*; Moreira Ana Paula; Habiel David; Ito Toshihiro; Coelho Ana Lucia; Allen Ron M; Hu Bin; Raphelson Janna; Carson William F; Schaller Matthew A; Lukacs Nicholas W; Omary M Bishr; Hogaboam Cory M; Kunkel Steven L

来源：PLos One, 2013, 8(6): e65899.

DOI：10.1371/journal.pone.0065899

Toll-like receptor (TLR) activation has been implicated in acetaminophen (APAP)-induced hepatotoxicity. Herein, we hypothesize that TLR3 activation significantly contributed to APAP-induced liver injury. In fasted wildtype (WT) mice, APAP caused significant cellular necrosis, edema, and inflammation in the liver, and the de novo expression and activation of TLR3 was found to be necessary for APAP-induced liver failure. Specifically, liver tissues from similarly fasted TLR3-deficient (tlr3(-/-)) mice exhibited significantly less histological and biochemical evidence of injury after APAP challenge. Similar protective effects were observed in WT mice in which TLR3 was targeted through immunoneutralization at 3 h post-APAP challenge. Among three important death ligands (i.e. TNF alpha, TRAIL, and FASL) known to promote hepatocyte death after APAP challenge, TNF alpha was the only ligand that was significantly reduced in APAP-challenged tlr3(-/-) mice compared with APAP-challenged WT controls. In vivo studies demonstrated that TLR3 activation contributed to TNFa production in the liver presumably via F4/80(+) and CD11c(+) immune cells. In vitro studies indicated that there was cooperation between TNF alpha and TLR3 in the activation of JNK signaling in isolated and cultured liver epithelial cells (i.e. nMuLi). Moreover, TLR3 activation enhanced the expression of phosphorylated JNK in APAP injured livers. Thus, the current study demonstrates that TLR3 activation contributes to APAP-induced hepatotoxicity.

• 出版日期2013-6-7