ABSTRACT
【Objective】 To investigate the in-vitro anti-inflammatory mechanism of luteolin by observing the effect of luteolin on nuclear factor-kappa B(NF?B) and COX-2 expression as well as DNA-binding activity of NF-?B in RAW264.7 cells activated by lipopolysaccharides(LPS).【Methods】RAW264.7 cells at logarithmic growth phase were allocated to blank control group,model group(treated with LPS) and luteolin groups(treated with 5,15,and 45 ?mol/L luteolin respectively).After being treated with luteolin for 30 min and then incubated with 1?g/mL LPS for 12 hours,the change of prostaglandin E2(PGE2) level was observed by enzyme immunoassay(EIA),DNA-binding activity of NF-?B was detected by electrophoretic mobility shift assay(EMSA),mRNA expression of COX-2 was examined by reverse transcription polymerase chain reaction(RT-PCR),and NF-?B and COX-2 protein expression in RAW264.7 cells was analysed by Western blotting.【Results】Luteolin obviously inhibited the formation of PGE2,decreased DNA-binding activity of NF-?B and down-regulated mRNA expression of COX-2 as well as NF-?B and COX-2 protein expression in RAW264.7 cells activated by LPS.【Conclusion】The antiinflammatory mechanism of luteolin may be related with the down-regulation of COX-2 expression by inhibiting the expression of NF-?B and DNA-binding activity.
