title: Effects of anti-allergy drugs on fMet-Leu-Phe-stimulated superoxide generation in human neutrophils.
abstract: We examined effects of six oral anti-allergy drugs used to treat bronchial asthma on fMet-Leu-Phe (N-formyl-methionyl-leucyl-phenylalanine)-induced superoxide (O2-) generation and mobilization of intracellular free calcium ([Ca2+]i) in human neutrophils. We also evaluated the direct action of these drugs on NADPH (reduced nicotinamide-adenine dinucleotide phosphate)-oxidase activity in cell lysate (cell-free system). Ketotifen (25 approximately 200 microM) enhanced fMet-Leu-Phe-stimulated O2- generation and [Ca2+]i mobilization, although it directly inhibited NADPH oxidase in the cell-free study. Low concentrations of oxatomide (5-20 microM) enhanced O2- generation, but concentrations > 25 microM inhibited O2- generation. In concentrations below 20 microM, oxatomide had no effects on fMet-Leu-Phe-stimulated [Ca2+]i mobilization, but at concentrations above 25 microM, it inhibited [Ca2+]i mobilization. Oxatomide inhibited NADPH oxidase activity at all concentrations examined. Azelastine, pemirolast, tranilast, and repirinast inhibited O2- generation and [Ca2+]i mobilization. Azelastine and pemirolast directly inhibited NADPH oxidase, but tranilast and repirinast did not. Our results indicated that except for ketotifen and low concentration of oxatomide, oral anti-allergy drugs used to treat bronchial asthma inhibited fMet-Leu-Phe-induced O2- generation in human neutrophils. Based on IC50 values, potency of drugs was as follows: oxatomide > azelastine > tranilast > pemirolast > repirinast.
authors.affiliation: Department of Pediatrics, Saga Medical School, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Hojo
authors.forename: Y
authors.initials: Y
authors.lastname: Hamasaki
authors.forename: I
authors.initials: I
authors.lastname: Fujita
authors.forename: H
authors.initials: H
authors.lastname: Koga
authors.forename: S
authors.initials: S
authors.lastname: Matsumoto
authors.forename: S
authors.initials: S
authors.lastname: Miyazaki
mesh_terms: D000328:Adult; D002118:Calcium / Q000378:metabolism; D005260:Female; D006634:Histamine H1 Antagonists / Q000627:therapeutic use; D006635:Histamine H2 Antagonists / Q000627:therapeutic use; D006801:Humans; D006967:Hypersensitivity / Q000188:drug therapy*; D008297:Male; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology*; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D019255:NADPH Oxidases; D009504:Neutrophils / Q000378:metabolism*; D013481:Superoxides / Q000378:metabolism*
chemical_list: D006634:Histamine H1 Antagonists; D006635:Histamine H2 Antagonists; D013481:Superoxides; D009240:N-Formylmethionine Leucyl-Phenylalanine; D009247:NADH, NADPH Oxidoreductases; D019255:NADPH Oxidases; D002118:Calcium