摘要
Background and aim:Overdose of acetaminophen(APAP)leads to liver injury,which is one of the most common causes of liver failure in the United States.We previously demonstrated that pharmacological activation of autophagy protects against APAP-induced liver injury in mice via removal of damaged mitochondria and APAP-adducts(APAP-ADs).Using an image-based high-throughput screening for autophagy modulators,we recently identified that chlorpromazine(CPZ),a dopamine inhibitor used for anti-schizophrenia,is a potent autophagy inducer in vitro.Therefore,the aim of the present study is to determine whether CPZ may protect against APAP-induced liver injury via inducing autophagy.Methods:Wild type C57BL/6J mice were injected with APAP to induce liver injury.CPZ was administrated either at the same time with APAP(co-treatment)or 2 h later after APAP administration(post-treat-ment).Hemotoxyline and eosin(H&E)staining of liver histology,terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling(TUNEL)staining of necrotic cell death as well as serum levels of alanine aminotransferase(ALT)were used to monitor liver injury.Results:We found that CPZ markedly protected against APAP-induced liver injury as demonstrated by decreased serum levels of ALT,liver necrotic areas as well as TUNEL-positive cells in mice that were either co-treated or post-treated with CPZ.Mechanistically,we observed that CPZ increased the number of autolysosomes and decreased APAP-induced c-Jun N-terminal kinase activation without affecting the metabolic activation of APAP.Pharmacological inhibition of autophagy by chloroquine partially weak-ened the protective effects of CPZ against APAP-induced liver injury.Conclusions:Our results indicate that CPZ ameliorates APAP-induced liver injury partially via activating hepatic autophagy and inhibiting JNK activation.
基金
This research was funded by the USA NIH R01 AA 020518,R01 DK 102142,U01 AA 024733,P20 GM 103549(COBRE),and P30 GM 118247(COBRE)。