CD36 deficiency ameliorates drug-induced acute liver injury in mice

Chen Zhang,Fengmeng Teng,Ting Zhao,Xiao Shi,Guozhong Ji,Chao Hu,Mengjing Li,Zhongping Su,Jinshun Pan,Tao Ling,Qiang You,Che Xu,Xianmin Mu

doi:10.1186/s10020-021-00325-z

Abstract

BackgroundAcetaminophen (APAP) overdose causes hepatotoxicity and even acute liver failure. Recent studies indicate that sterile inflammation and innate immune cells may play important roles in damage-induced hepatocytes regeneration and liver repair. The scavenger receptor CD36 has its crucial functions in sterile inflammation. However, the roles of CD36 in APAP induced acute liver injury remain unclear and warrant further investigation.MethodsWT C57BL/6 J and CD36−/− mice were intraperitoneally injected with APAP (300 mg/kg) after fasting for 16 h. Liver injury was evaluated by serum alanine aminotransferase (ALT) level and liver tissue hematoxylin and eosin (H&E) staining. Liver inflammatory factor expression was determined by real-time polymerase chain reaction (PCR). The protein adducts forming from the metabolite of APAP and the metabolism enzyme cytochrome P450 2E1 (CYP2E1) levels were measured by Western blot. Liver infiltrating macrophages and neutrophils were characterized by flow cytometry. RNA sequencing and Western blot were used to evaluate the effect of damage-associated molecular patterns (DAMP) molecule high mobility group B1 (HMGB1) on WT and CD36−/− macrophages. Moreover, PP2, a Src kinase inhibitor, blocking CD36 signaling, was applied in APAP model.ResultsThe expression of CD36 was increased in the liver of mice after APAP treatment. Compared with WT mice, APAP treated CD36−/− mice show less liver injury. There was no significant difference in APAP protein adducts and CYP2E1 expression between these two strains. However, reduced pro-inflammatory factor mRNA expression and serum IL-1β level were observed in APAP treated CD36−/− mice as well as infiltrating macrophages and neutrophils. Moreover, CD36 deficiency impaired the activation of c-Jun N-terminal kinase (JNK) caused by APAP. Interestingly, the lack of CD36 reduced the activation of extracellular regulated protein kinases (Erk) and v-akt murine thymoma viral oncogene homolog (Akt) induced by HMGB1. RNA transcription sequencing data indicated that HMGB1 has a different effect on WT and CD36−/− macrophages. Furthermore, treatment with PP2 attenuated APAP induced mouse liver injury.ConclusionOur data demonstrated that CD36 deficiency ameliorated APAP-induced acute liver injury and inflammatory responses by decreasing JNK activation. CD36 might serve as a new target to reduce acute liver injury.

Highlights

Acetaminophen (APAP) overdose causes hepatotoxicity, and even acute liver failure, which involves a series of critical events including APAP metabolite protein adduct formation, mitochondrial dysfunction, oxidant stress, peroxynitrite formation and nuclear DNA fragmentation (McGill 2012)
The cell necrosis leads to the release of damage-associated molecular patterns (DAMPs) including high mobility group B1 (HMGB1) protein, DNA fragments, and heat shock proteins, which can be recognized by the receptors on monocytes and macrophages and results in their activation and inflammatory responses (Martin-Murphy et al 2010; Jeannin et al 2008; Schwabe et al 2006)
CD36 deficiency attenuates APAP‐induced liver injury in mice In order to investigate the role of CD 36 in APAPinduced liver injury, the expression of CD36 level was determined in the livers from mice with APAP overdosage

Summary

Introduction

Acetaminophen (APAP) overdose causes hepatotoxicity, and even acute liver failure, which involves a series of critical events including APAP metabolite protein adduct formation, mitochondrial dysfunction, oxidant stress, peroxynitrite formation and nuclear DNA fragmentation (McGill 2012). Recent studies indicate that sterile inflammation and innate immune cells may play important roles in damage-induced hepatocyte regeneration and liver repair (Woolbright and Jaeschke 2017). The cell necrosis leads to the release of damage-associated molecular patterns (DAMPs) including HMGB1 protein, DNA fragments, and heat shock proteins, which can be recognized by the receptors on monocytes and macrophages and results in their activation and inflammatory responses (Martin-Murphy et al 2010; Jeannin et al 2008; Schwabe et al 2006). Recent studies indicate that sterile inflammation and innate immune cells may play important roles in damage-induced hepatocytes regeneration and liver repair. PP2, a Src kinase inhibitor, blocking CD36 signaling, was applied in APAP model

Methods

Results

Conclusion