AIM: To assess whether treatment with insulinsensitizing agents (ISAs) in combination with ezetimibe and valsartan have greater effect on hepatic fat content and lipid peroxidation compared to monotherapy in the methionine choline-deficient diet (MCDD) rat model of non-alcoholic fatty liver disease (NAFLD).METHODS: Rats (n = 6 per group) were treated with different drugs, including MCDD only, MCDD diet with either metformin (200 mg/kg), rosiglitazone (3 mg/kg),metformin plus rosiglitazone (M+R), ezetimibe (2 mg/kg), valsartan (2 mg/kg), or combination of all drugs for a total of 15 wk. Liver histology, lipids, parameters of oxidative stress and TNF-alpha were measured.RESULTS: Fatty liver (FL) rats demonstrated severe hepatic fatty infiltration (＞ 91% fat), with an increase in hepatic TG (+1263%, P ＜ 0.001), hepatic cholesterol (+245%, P ＜ 0.03), hepatic MDA levels (+225%, P ＜0.001), serum TNF-alpha (17.8 ± 10 vs 7.8 ± 0.0, P ＜ 0.001), but a decrease in hepatic alpha tocopherol (-74%, P ＜ 0.001) as compared to the control rats.Combination therapy with all drugs produced a significant decrease in liver steatosis (-54%), hepatic TG (-64%), hepatic cholesterol (-31%) and hepatic MDA (-70%), but increased hepatic alpha tocopherol (+443%)as compared to FL rats. Combination therapy with ISA alone produced a smaller decrease in liver steatosis (-32% vs -54%, P ＜ 0.001) and in hepatic MDA levels (-55% vs -70%, P ＜ 0.01), but a similar decrease in hepatic lipids when compared with the all drugs combination.TNF-alpha levels decreased significantly in all treatment groups except in ISA group.CONCLUSION: Combination therapies have a greater effect on liver fat content as compared to monotherapy.Rosiglitazone appears to improve hepatic steatosis to a greater extent than metformin.