title: Effect of antioxidant supplementation on ozone-induced lung injury in human subjects.
abstract: To determine whether antioxidants can influence human susceptibility to ozone (O(3))-induced changes in lung function and airway inflammation, we placed 31 healthy nonsmoking adults (18 to 35 yr old) on a diet low in ascorbate for 3 wk. At 1 wk, subjects were exposed to filtered air for 2 h while exercising (20 L/min/m(2)), and then underwent bronchoalveolar lavage (BAL) and were randomly assigned to receive either a placebo or 250 mg of vitamin C, 50 IU of alpha-tocopherol, and 12 oz of vegetable cocktail daily for 2 wk. Subjects were then exposed to 0.4 ppm O(3) for 2 h and underwent a second BAL. On the day of the O(3) exposure, supplemented subjects were found to have significantly increased levels of plasma ascorbate, tocopherols, and carotenoids as compared with those of the placebo group. Pulmonary function testing showed that O(3)-induced reductions in FEV(1) and FVC were 30% and 24% smaller, respectively, in the supplemented cohort. In contrast, the inflammatory response to O(3) inhalation, as represented by the percent neutrophils and the concentration of interleukin-6 recovered in the BAL fluid at 1 h after O(3) exposure was not different for the two groups. These data suggest that dietary antioxidants protect against O(3)-induced pulmonary function decrements in humans.
authors.affiliation: Human Studies Division, National Health and Environmental Effects Research Laboratory, Environmental Protection Agency, Research Triangle Park, USA. samet.jim@epa.gov
authors.forename: J M
authors.initials: JM
authors.lastname: Samet
authors.forename: G E
authors.initials: GE
authors.lastname: Hatch
authors.forename: D
authors.initials: D
authors.lastname: Horstman
authors.forename: S
authors.initials: S
authors.lastname: Steck-Scott
authors.forename: L
authors.initials: L
authors.lastname: Arab
authors.forename: P A
authors.initials: PA
authors.lastname: Bromberg
authors.forename: M
authors.initials: M
authors.lastname: Levine
authors.forename: W F
authors.initials: WF
authors.lastname: McDonnell
authors.forename: R B
authors.initials: RB
authors.lastname: Devlin
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000139:chemically induced* / Q000517:prevention & control*; D008297:Male; D010126:Ozone / Q000009:adverse effects*
chemical_list: D000975:Antioxidants; D010126:Ozone