AimTo explore whether SIRT1 interacts with liver X receptor-α, the level of liver X receptor-α acetylation and the relationship between liver X receptor-α acetylation and intracellular cholesterol content during THP-1 macrophages foam-cell formation.MethodsTHP-1 macrophages were used to build foam-cell model, the changes of intracellular cholesterol content was detected by high performance liquid chromatography, the level of liver X receptor-α acetylation, the level of SIRT1 expression, and the interaction between liver X receptor-α and SIRT1 were detected by western blot and co-immunoprecipitation respectively.Results After oxidized low-density lipoprotein treated for 12 h, 24 h, 48 h, the cellular cholesterol content of THP-1 macrophages cell was increased gradually, SIRT1 interact with liver X receptor-α, liver X receptor-α acetylation decreased, whereas SIRT1 expression increased.ConclusionDuring THP-1 macrophages foam-cell formation, decreased level of acetylated liver X receptor-α was related to up-regulated expression of SIRT1.