Activity of monomeric, dimeric, and trimeric flavonoids on NO production, TNF‐α secretion, and NF‐κB‐dependent gene expression in RAW 264.7 macrophages

Abstract

Flavonoids are potent antioxidants and have been associated with lowering the risk of cardiovascular diseases. In this study, the effect of flavonoids (monomers, dimers and a trimer) as well as French maritime pine bark extract, Pycnogenol, on NO production, tumor necrosis factor-K K (TNF-K K) secretion and nuclear factor (NF)-U UB activity was compared. Monomers and dimers repressed NO production, TNF-K K secretion and NF-U UB-dependent gene expression induced by interferon Q Q, whereas the trimeric procyanidin C2 and Pycnogenol enhanced these parameters. In addition, in unstimulated RAW 264.7 macrophages, both procyanidin C2 and Pycnogenol increased TNF-K K secretion in a concentration-and timedependent manner. These results demonstrate that procyanidins act as modulators of the immune response in macrophages.z 2000 Federation of European Biochemical Societies.

Polymeric proanthocyanidins from Sicilian pistachio (Pistacia vera L.) nut extract inhibit lipopolysaccharide-induced inflammatory response in RAW 264.7 cells

“…Values not sharing the same letter were significantly different (p \ 0.05, Fisher's test) PGE 2 , and TNF-a, with oligomers poorly effective with respect to polymers that contributed almost entirely to the HPE activity. These data may be the reflection of the amounts of proanthocyanidins assayed and/or indicate a different ability of oligomers and polymers to affect the macrophage response, as observed in other researches [44,[46][47][48][49]. To further highlight the role of these components, PF was also found almost effective as the whole HPE in inhibiting phosphorylation, and then activation, of IjB-a.…”

Techniques for quantifying effects of dietary antioxidants on transcription factor translocation and nitric oxide production in cultured cells

“…Second, a decrease was observed when using Pycnogenol® as a positive control. Previous studies of the effects of Pycnogenol® on NF-kB translocation in RAW 264.7 cells have given apparently contradictory effects - Park et al (2000) found it increased translocation, Cho et al (2000) found a decrease, and Virgili et al (1998) found no effect. However, these discrepancies can be explained by the use of different agents to activate the cells.…”

Potential anti-inflammatory, anti-adhesive, anti/estrogenic, and angiotensin-converting enzyme inhibitory activities of anthocyanins and their gut metabolites

“…An equal volume of the Griess reagent (1% sulfanilamide/0.1% N-(1-naphthyl)-ethylenediamine dihydrochloride/2.5% H 3 PO 4 ) and the deproteinized samples were incubated for 10 min at room temperature protected from light. The nitrite concentration was determined by measuring the absorbance at 548 nm against a standard curve for sodium nitrite (Park et al 2000).…”