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Effect of Vitamin C on Transient Increase of Bronchial Responsiveness in Conditions Affecting the Airways
Author(s) -
BUCCA C.,
ROLLA G.,
FARINA J. C.
Publication year - 1992
Publication title -
annals of the new york academy of sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.712
H-Index - 248
eISSN - 1749-6632
pISSN - 0077-8923
DOI - 10.1111/j.1749-6632.1992.tb17098.x
Subject(s) - medicine
The recent growth in our knowledge of the metabolic properties of vitamin C has provided clues for investigating its effectiveness in conditions of increased bronchial reactivity (BR). The term increased BR describes the exaggerated bronchoconstrictive response to a variety of physical or chemical stimuli, typically shown by asthmatic patients.'-4 The mechanisms by which vitamin C may counteract increased BR include its ability to shift prostaglandin biosynthesis from constrictor PGF?, to dilator PGE,,5 to promote nonenzymatic histamine degradation,6 to stimulate catecholamine bio~ynthesis,~ to decrease smooth muscle contractilit^,^.^ and to mantain the lung redox state.'O Acute and short-term effects of vitamin C on increased BR of asthmatic patients have been investigated, with conflicting results."-'4 These contrasts might depend on the great interindividual variability in the pathologic manifestations of asthma: airway inflammationI5 and damage of bronchial epithelium. I 6 We reasoned that vitamin C, by its metabolic properties, could better display its protective effect in conditions in which increased BR is of recent onset. Actually, the extensive use of nonspecific bronchial challenges in recent years has shown that several conditions, besides asthma, may induce a shift in BR. These include viral infections of the upper respiratory t r a ~ t , ' ~ ? ~ atopic rhiniti~,?''~ exposure to air-borne pollutant^,?^-^^ and cigarette ~moking .?~ .?~ Although the increase in BR in these conditions is usually milder than that observed in asthma, they share some pathogenetic mechanisms in common with asthma, such as airway i n f l a m m a t i ~ n , ' ~ ~ * ~ , ~ ~ ~ ' with release of mediators and toxic oxygen radicals. To explore this hypothesis, we performed a series of investigations on the effects of large doses of vitamin C on lung function and bronchial reactivity to histamine in subjects with viral infections of the upper respiratory tract,)* in patients with seasonal allergic r h i n i t i ~ , ~ ~ in policemen with occupational exposure to urban air p o l l ~ t a n t s , ~ ~ and in heavy cigarette smoker^.^'