To investigate the anti-inflammatory effects of aqueous extract of Orixa japonica
(AEOJ) in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells.
The expression of mRNA and protein using RT-PCR and Western blot analysis was investigated. The level of nitric oxide (NO) production was analyzed using Griess reaction. Release of prostaglandin E2 (PGE2
) and tumor necrosis factor-α (TNF-α) was determined using sandwich ELISA.
AEOJ potently inhibited the production of nitric oxide (NO), prostaglandin E2 (PGE2
), and tumor necrosis factor-α (TNF-α) in LPS-stimulated RAW 264.7 cells. Consistent with these findings, AEOJ was also found to significantly reduce LPS-induced expression of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), and TNF-α at the transcriptional level. Additionally, AEOJ attenuated LPSinduced NF-κB activity via the inhibition of IκB phosphorylation and degradation. It was also found that the NF-κB inhibitor N-acetyl cysteine (NAC) attenuated LPS-induced gene expression of iNOS, COX-2, and TNF-α. These results indicate that AEOJ attenuates LPS-induced inflammatory mediators such as NO, PGE2
, and TNF-α via suppression of NF-κB activity.
These results suggest that AEOJ has a potential activity to alleviate LPS-induced inflammation.