Protective Effects Of Soy Isoflavone And Soyasaponin Against Acute Alcohol-induced Liver Injury

Objective: Alcohol consumption increased rapidly along with the great economic growth of china since the 1980s, health problems caused by alcohol consumption include alcoholic liver disease became more and more serious, meanwhile. The prevalence of alcoholic liver disease in china has increased markedly according to the epidemiological data. Oxidative stress, inflammatory and immunological injury are the main pathogeny of alcoholic liver disease, while soy isoflavone and soyasaponin have been confirmed to have high antioxidant effects. Researches from our laboratary before also show these two phytochemicals have protective effects against the liver injury of carbon tetrachloride. This study will investigate the effects of soy isoflavone and soyasaponin on acute alcohol-induced liver injury using ICR mice as the alcoholic liver injury exeperimental model.Methods: According to"Norms on Health-Care Food Examination and Technology Assessment"of China's Ministry of Health, 80 ICR adult female mouse were divided into 6 groups randomly by weight, including normal group, model group, low dosage soy isoflavone group(30 mg/kg·bw), high dosage soy isoflavone group(60 mg/kg·bw), low dosage soyasaponin group(30 mg/kg·bw) and high dosage soyasaponin group(60 mg/kg·bw), During the experiment, the four test groups were intragastrically administered soy isoflavone or soyasaponin solution every day, and the normal group and the model group were administered the same Volume of dissolvent. After 30 days of administration, mouse of all groups except the normal group were administered water alcohol solution containing 50% of alcohol at a dose of 12~14ml per kg of bodyweight, then all mouse were fasted for 12 hours and killed. Then liver index, liver and brain malondialdehyde content, liver and plasma reduced glutathione content, liver triglyceride content were assayed and liver pathological examination was also implemented.Results: There was no difference in body weight and weight gain during the experiment among groups. The liver index of the model group was higher than that of the normal group, ?but had no difference from the indexs of the four test groups. Compared with the model group, the liver malondialdehyde content was much lower in normal group and all the test groups, but there was no difference among the test groups. The liver reduced glutathione content of the model group decreased compared with the normal group, and it was significantly lower than the test groups′except the low dosage soyasaponin group′s index. The plasma reduced glutathione content of the model group was lower than that of the normal group, but only the high dosage soyasaponin group had significantly higher plasma reduced glutathione content than the model group did. The liver triglyceride content of the model group was much higher compared with the normal group, the liver triglyceride content of all the test groups was significantly lower than that of the model group. The liver pathological examination showed that there was evident steatosis in the liver of the model group, lipid droplets could be seen widely distributed. Steatosis in the liver of the test groups decreased significantly compared with the model group.Conclusions: In this research, both of soy isoflavone and soyasaponin exert antioxidant activity via reducing the lipid peroxidation and antioxidation system depletion induced by alcohol. They also can reduce the steatosis in acute alcohol-induced liver injury.In short, soy isoflavone and soyasaponin both have protective effects against acute alcohol-induced liver injury.