Antioxidant activity of micronized diosmin on oxygen species from stimulated human neutrophils

• Published in: Biochemical pharmacology Vol. 45; no. 7; pp. 1531 - 1535
• Main Authors: Cypriani, Benoit, Limasset, Benjamin, Carrie, Marie-Luce, Le Doucen, Christian, Roussie, Martine, De Paulet, AndréCrastes, Damon, Marcelle
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 06.04.1993; Elsevier Science
• Subjects: Acridines; Antioxidants - pharmacology; Biological and medical sciences; Diosmin - pharmacology; Drug Combinations; Free Radicals; General and cellular metabolism. Vitamins; Hesperidin; Humans; Luminescent Measurements; Luminol; Medical sciences; Neutrophils - drug effects; Neutrophils - metabolism; Peroxidase; Pharmacology. Drug treatments; Reactive Oxygen Species; Tetradecanoylphorbol Acetate; G, glucose; HRP, horseradish peroxidase; PBS, phosphate-buffered saline; PKC, protein kinase C; CL, chemiluminescence; SOD, Superoxide dismutase; XO, xanthin oxidase; PMN, polymorphonuclear neutrophil; PMA, phorbol myristate acetate; MPO, myeloperoxidase; X, xanthin; GO, glucose oxidase; Human; Oxygen; Neutrophil; Antioxidant; Mechanism of action; Flavonoid; In vitro; Biological activity; Hesperidin
• ISSN: 0006-2952; 1873-2968
• DOI: 10.1016/0006-2952(93)90056-3

Flavonoids are known to reduce reactive oxygen species released by polymorphonuclear neutrophils (PMNs) in vitro. We have studied the effects of S5682 (Daflon 500 mg), a purified flavonoid fraction composed of 90% diosmin and 10% hesperidin. S5682 produced a dose-dependent inhibition of the luminol chemiluminescence (CL) induced by phorbol myristate acetate on PMNs ( ic 50 = 5 × 10 −5 M) , with no effect on Superoxide anion (O 2 −) formation and on cellular Superoxide dismutase activity as determined by lucigenin-amplified CL. The CL results were confirmed by the hydrogen peroxide (H 2O 2) determination showing that S5682 reduced H 2O 2 formed through either PMN stimulation ( ic 50 = 1.6 × 10 −6 M) or an in vitro enzymatic mechanism ( ic 50 = 2 × 10 −6 M) . S5682 inhibited luminol-dependent CL induced by H 2O 2 ( ic 50 = 5 × 10 −6 M) . However, O 2 was not formed from H 2O 2 in contact with S5682 and the UV spectrum of this compound was not modified. In contrast, S5682 inhibited luminol-dependent CL induced by H 2O 2 in the presence of horseradish peroxidase ( ic 50 = 3 × 10 −6 M) , and the UV spectrum of S5682 was modified. Luminol-dependent CL induced by hypochlorite (OCl − 10 −5 M) was also inhibited by S5682 ( ic 50 = 7 × 10 −5 M) . This inhibitory effect was similar to that of sodium azide on myeloperoxidase activity. Moreover, OCl − 5 × 10 −4 M also altered the UV spectrum of S5682 10 −4 M. These results indicate that S5682 could be active on the H 2O 2OCl −-myeloperoxidase system.