Influence of anti-inflammatory flavonoids on degranulation and arachidonic acid release in rat neutrophils.

We assessed the effects of 24 flavonoid derivatives, reported as anti-inflammatory, on lysosomal enzyme secretion and arachidonic acid release in rat neutrophils. Amentoflavone, quercetagetin-7-O-glucoside, apigenin, fisetin, kaempferol, luteolin and quercetin were the most potent inhibitors of beta-glucuronidase and lysozyme release. The first compound was also able to inhibit basal release. These flavonoids besides chrysin and to a reduced extent, naringenin, significantly inhibited arachidonic acid release from membranes. A correlation between degranulation and arachidonic acid release was found for this series of compounds. Structure-activity relationships and implications for the anti-inflammatory effects of these flavonoids were discussed.