Abstract: ObjectiveTo investigate the effects of lycopene on inflammatory responses to lipopolysaccharide(LPS) in RAW264.7 macrophages.MethodsReverse transcription-PCR(RT-PCR)was used to detect inducible nitric oxide synthase(iNOS)and interleukin-6(IL-6)gene expression.Western blot was used to analyze iNOS protein expression.Additionally,the LPS-induced nitric oxide(NO)and IL-6 release in macrophages were assayed with Griess and enzymelinked immunosorbert assay(ELISA).ResultsThe NO contents of moderate and high dose lycopene treatment groups were 40.6±1.5 and 26.6±1.3μmol/L and significantly lower than that of control group(56.3±2.5μmol/L;F=18.3, P<0.01).The contents of IL-6 were 508.3±39.5,469.2±66.9,and 335.5±72.9 pg/mL for low moderate,and high dose lycopene treatment groups,respectively,and significantly lower than that of the control group(603.4±16.8;F=92.6, P<0.05).Lycopene inhibited LPS-induced iNOS and IL-6 expression with NO and IL-6 release in macrophages.ConclusionLycopene can cause inhibition of LPS-induced iNOS and IL-6 at mRNA and protein levels together with the decreases in NO and IL-6 production,indicating that it can be used as a potential anti-inflammatory reagent to treat inflammatory-related diseases such as atherosclerosis.