Scavengers of active oxygen species prevent cigarette smoke-induced asbestos fiber penetration in rat tracheal explants.

It was previously shown that rat tracheal explants first exposed to cigarette smoke and then to amosite asbestos take up more asbestos fibers than explants exposed to air and asbestos. To examine the mechanism of this process, the same experimental design was followed but test groups were added in which the asbestos was mixed with catalase or superoxide dismutase, scavengers of active oxygen species, or deferoxamine, an iron chelator that prevents formation of hydroxyl radical. All three agents protected against the cigarette smoke effect. Heat inactivated catalase or superoxide dismutase was not protective. These observations indicate that active oxygen species, probably derived from the cigarette smoke, play a role in smoke-mediated fiber transport into tracheobronchial epithelia.