This study was performed to investigate the effect of Aruncus dioicus var. kamtschaticus Hara (AD) ethanol extract on alcohol-induced liver injury in rat. Male Sprague-Dawley rats were randomly divided into six groups (n=6) based on six dietary categories: control (Control), ethanol (EtOH), ethanol plus 500 ppm AD (EtOH+500AD), ethanol plus 1000 ppm AD (EtOH+1000AD), ethanol plus 1500 ppm AD (EtOH+1500AD) and ethanol plus 1500 ppm silymarin (EtOH+1500SM). Lieber DeCarli ethanol liquid diet containing 5% ethanol was given to the animals to induce alcoholic liver injury for 4 weeks. Control diet was isocalorically substituted maltose-dextrin for ethanol.
Liver function, such as glutamate oxaloacetate transaminase (AST), glutamate pyruvate transaminase (ALT) and ?-glutamyl transpeptidase (?-GT) and lipid profiles, such as triglyceride (TG), total-cholestrol (TC) and HDL-cholesterol (HDL-C), were analyzed in plasma. Alcohol metabolism enzymes, such as alcohol dehydrogenase (ADH), cytochrome P450 2E1 (CYP2E1) and acetaldehyde dehydrogenase (ALDH) activities were analyzed in liver. Glutathione (GSH) and antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST) activities in blood and liver were also analyzed. The mRNA levels of key antioxidant defence system in liver were assessed by quantitative real-time polymerase chain reaction analyses. Thiobarbituric acid reactive substances (TBARS) in blood and liver were measured and histopathological changes of liver tissue was examined.
The results showed that AD supplemented diet significantly lowered ?-GT and TG in plasma, and significantly increased ADH and ALDH activities, but decreased CYP2E1 protein level in liver compared to those of EtOH group. AD supplementation resulted in a significant decrease in TBARS levels, whereas a significant increase in GSH levels in blood and liver compared to those of EtOH group. And GPx activity in liver and CAT activities in RBC and hepatic mitochondria significantly increased in rats fed AD supplemented diet compared to those of rats fed ethanol alone. Hepatic histopathological examination showed that AD administration decreased fat accumulation in liver compared to that of EtOH group. Accordingly, our present study suggests that Aruncus dioicus var. kamtschaticus Hara ethanol extract may ameliorate alcohol-induced liver injury by enhancing alcohol metabolic pathways and antioxidant defense system.