Flavonoid modulation of human neutrophil function.
Flavonoids are naturally occurring plant compounds that have been demonstrated to possess a variety of anti-inflammatory effects. We studied the effects of flavonoids on three aspects of neutrophil function that are commonly considered to be associated with inflammation: the release of lysosomal enzymes, the chemiluminescence (CL) response, and the production of superoxide anion. Quercetin and eight other flavonoids at a 10(-5)M concentration inhibited the neutrophil CL response to opsonized zymosan particles by approximately 60% or more. In contrast, the release of lysosomal beta-glucuronidase from neutrophils stimulated with opsonized zymosan was only inhibited by two flavonoids, quercetin and chalcone, and only at concentrations of 1.5 X 10(-4)M to 2 X 10(-4)M. Quercetin also inhibited the generation of superoxide anion by neutrophils but to a lesser degree than its effect on CL. The present studies demonstrated that certain flavonoids are not uniformly active in inhibiting neutrophil CL, beta-glucuronidase release, or superoxide generation. The effects of flavonoids on neutrophil functions probably depend on many variables including the response measured, the activating stimulus, and specific flavonoid structural features.
D000242:Cyclic AMP / Q000097:blood; D005419:Flavonoids / Q000494:pharmacology*; D005966:Glucuronidase / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000517:prevention & control*; D008163:Luminescent Measurements; D009504:Neutrophils / Q000187:drug effects*; D010101:Oxygen Consumption / Q000187:drug effects; D010587:Phagocytosis; D011794:Quercetin / Q000494:pharmacology; D013481:Superoxides / Q000096:biosynthesis; D015054:Zymosan / Q000494:pharmacology
D005419:Flavonoids; D013481:Superoxides; D015054:Zymosan; D011794:Quercetin; D000242:Cyclic AMP; D005966:Glucuronidase