Chalcone Derivative L6H21 Reduces EtOH+LPS-Induced Liver Injury Through Inhibition of NLRP3 Inflammasome Activation.

Abstract

Chronic alcohol intake increases circulating endotoxin levels causing excessive inflammation that aggravates the liver injury. (E)-2,3-dimethoxy-4'-methoxychalcone (L6H21), a derivative of chalcone, has been found to inhibit inflammation in cardiac diseases and nonalcoholic fatty liver disease. However, the use of L6H21 in alcoholic liver disease to inhibit exotoxin-associated inflammation has not been explored. In this study, we examined the effects of L6H21 on EtOH+LPS-induced hepatic inflammation, steatosis, and liver injury and investigated the underlying mechanisms. C57BL6 mice were treated with 5% EtOH for 10days, and LPS was given to the mice 6hours before sacrificing. One group of mice was supplemented with L6H21 with EtOH and LPS. RAW264.7 cells were used to analyze the effects of L6H21 on macrophage activation. EtOH+LPS treatment significantly increased hepatic steatosis and serum levels of alanine transaminase (ALT) and aspartate transaminase (AST), which were reduced by L6H21 treatment. EtOH+LPS treatment increased hepatic inflammation, as shown by the increased hepatic protein levels of Toll-like receptor-4, p65, and p-IκB, and increased oxidative stress, as shown by protein carbonyl levels and reactive oxygen species formation, which were reduced by L6H21 treatment. In addition, L6H21 treatment markedly inhibited EtOH+LPS-elevated hepatic protein levels of NLRP3, cleaved caspase-1, cleaved IL-1β, and caspase-1-associated apoptosis. Our results demonstrate that L6H21 treatment inhibits EtOH+LPS-induced liver steatosis and injury through suppression of NLRP3 inflammasome activation. L6H21 may be used as an alternative strategy for ALD prevention/treatment.