Effect of a plant histaminase on asthmalike reaction induced by inhaled antigen in sensitized guinea pig.
This study evaluates the effects of a copper amine oxidase (histaminase) purified from the pea seedling as a free or immobilized enzyme on asthmalike reactions to inhaled antigen in actively sensitized guinea pig in vivo. Male albino guinea pigs, sensitized with ovalbumin, were challenged with the antigen given by aerosol; free histaminase or CNBr-Sepharose immobilized histaminase was given intraperitoneally (20 microg, 3 or 24 h before antigen challenge) or by aerosol (4 microg, 30 min before or during ovalbumin aerosol). The following parameters were examined: latency time for the onset of respiratory abnormalities, cough severity score, and occurrence and duration of dyspnea. We also evaluated lung histopathology, mast cell degranulation, and lung myeloperoxidase and malonydialdehyde levels. Histaminase significantly reduced the severity of cough and the occurrence of dyspnea and delayed the onset of respiratory abnormalities. Both enzymes prevented bronchial constriction, pulmonary air space inflation, leukocyte infiltration (evaluated as myeloperoxidase activity), and lipoperoxidation of cell membranes (evaluated as malonyldialdehyde production). No relevant differences in pharmacological potency were noted between free or immobilized enzyme. This study provides evidence that histaminase counteracts acute allergic asthmalike reaction in actively sensitized guinea pigs, raising the possibility of new therapeutic strategies for allergic asthma in humans.
Masini
Emanuela
E
Department of Preclinical and Clinical Pharmacology, University of Florence, Viale G. Pieraccini, 6, 50139 Florence, Italy. emanuela.masini@unifi.it
Vannacci
Alfredo
A
Giannini
Lucia
L
Befani
Olivia
O
Nistri
Silvia
S
Mateescu
Mircea Alexandru
MA
Mannaioni
Pier Francesco
PF
Mondovì
Bruno
B
Federico
Rodolfo
R
D000280:Administration, Inhalation; D000336:Aerosols; D006631:Amine Oxidase (Copper-Containing) / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D000941:Antigens / Q000008:administration & dosage*; D001249:Asthma / Q000188:drug therapy / Q000201:enzymology / Q000276:immunology; D003371:Cough / Q000188:drug therapy / Q000201:enzymology / Q000276:immunology; D004800:Enzymes, Immobilized / Q000097:blood; D006168:Guinea Pigs; D007114:Immunization / Q000379:methods; D007274:Injections, Intraperitoneal; D008168:Lung / Q000187:drug effects / Q000201:enzymology; D008297:Male; D010047:Ovalbumin / Q000008:administration & dosage / Q000276:immunology; D018532:Pisum sativum; D012129:Respiratory Function Tests; D012130:Respiratory Hypersensitivity / Q000188:drug therapy* / Q000201:enzymology* / Q000276:immunology; D036226:Seedlings
D000336:Aerosols; D000941:Antigens; D004800:Enzymes, Immobilized; D010047:Ovalbumin; D006631:Amine Oxidase (Copper-Containing)