Figure 5: Effects of treatments with four different flavonoids on lipopolysaccharide (LPS)-induced pro-inflammatory cytokines and cyclooxygenase-2 and inducible nitric oxide synthase protein expressions. RAW264.7 cells were treated with or without 1 μg/mL LPS and 12.5 μg/mL quercetin (Q), kaempferol (K), galangin (G), or curcumin (C) for 24 h. (a-c) Levels of interleukin-1β (a), interleukin-6 (b), and tumor necrosis factor-α (c) in media were determined by ELISA. The cyclooxygenase-2 and inducible nitric oxide synthase expression levels were evaluated by Western blots (d). The expression level of each protein was quantified using ImageJ software. After normalization by β-actin, relative cyclooxygenase-2 (e) and inducible nitric oxide synthase (f) expression levels are shown. L + Q: treated with LPS and Q, L + K: treated with LPS and K, L + G: treated with LPS and G, L + C: treated with LPS and C. #P < 0.05 compared to NC *P < 0.05 compared to LPS.