Figure 1

DPPH-scavenging activity, NO-scavenging activity, metal chelation and serum oxidationA: DPPH-scavenging activity of BWE and rutin. Ascorbic acid was used as the positive control, and values are expressed as mean ± standard deviation, n = 5. B: Nitric oxide-scavenging activity of BWE and rutin. Ascorbic acid was used as the positive control, and values are expressed as mean ± standard deviation, n = 5. C: Chelating activity of BWE and rutin; values are expressed as mean ± standard deviation, n = 5. D: Effects of BWE and rutin on serum lipid oxidation. *P<0.05, **P<0.01, vs control (sample-untreated but CuSO4-treated). Butylated hydroxytoluene was used as positive control; values are expressed as mean ± standard deviation, n = 5. DPPH: 1,1-diphenyl-2-picryl hydrazyl; NO: nitric oxide; BWE: buckwheat extract; BHT: butylated hydroxytoluene; TBARS: thiobarbituric acid reactive substance."

Figure 2

Viability of RAW264.7 cells and NO production RAW264.7 cells were pre-treated with samples for 1 h followed by stimulation of the cells with LPS for additional 24 h. A: The cell viability was determined by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. B: NO production was measured by using Griess reagent. Values are expressed as mean ± standard deviation, n = 3. *P<0.05, **P<0.01, vs control (LPS-treated, sample-untreated). NO: nitric oxide; BWE: buckwheat extract; LPS: lipopolysaccharide."

Figure 3

iNOS and COX-2 expressionRAW264.7 cells were pre-treated with samples for 1 h followed by stimulation of the cells with LPS for additional 24 h. Then, the expression of iNOS and COX-2 was determined by Western blot analysis. b-actin was used for normalization. Values are expressed as mean ± standard deviation, n = 3. *P<0.05 , **P<0.01, vs control (LPS-treated, sample-untreated). iNOS: inducible nitric oxide synthase; COX-2: cyclooxygenase-2; BWE: buckwheat extract; LPS: lipopolysaccharide."

Figure 4

TNF-α and IL-6 production RAW264.7 cells were pre-treated with samples for 1 h followed by stimulation of the cells with LPS for additional 24 h. The levels of TNF-α and IL-6 in supernatant were measured by using enzyme-linked immunosorbent assay. Values are expressed as mean ± standard deviation, n = 3. *P<0.05, **P<0.01, vs control (LPS-treated, sample-untreated). TNF-α: tumor necrosis factor-α; IL-6: interleukin-6; BWE: buckwheat extract; LPS: lipopolysaccharide."

Figure 5

NF-κB translocationRAW264.7 cells were pre-treated with samples for 1 h followed by stimulation of the cells with LPS for additional 30 min. The expression of NF-κB p65 subunit in the cytosolic and nuclear fractions was determined by Western blot analysis. Values are expressed as mean ± standard deviation, n = 3. *P<0.05, **P<0.01, vs control (LPS-treated, sample-untreated). NF-κB: nuclear factor-kappa B; PCNA: proliferating cell nuclear antigen; BWE: buckwheat extract; LPS: lipopolysaccharide."