The Role of Vitamins E and C in Maintaining Lung Health in People With Asthma

Eosinophils and neutrophils are inflammatory cells located in the airways and lungs. When they are activated, they generate oxidants, which irritates the mucosal cells in the airways. As a result, mucus develops in the lungs. Allergens can activate the inflammatory cells, thereby worsening the symptoms of asthma in allergic asthmatics. Vitamins E (alpha-tocopherol) and C (ascorbate) have been shown to decrease asthma exacerbation associated with exposure to ozone. Enhancing antioxidant and anti-inflammatory defenses in the airways and lungs is a promising approach for treating respiratory diseases aggravated by allergies. This study will determine if airway antioxidants in allergic asthmatics are enhanced with a combination of vitamin E and vitamin C therapy. Participants in this double-blind study will be randomly assigned to receive either a combination of alpha-tocopherol and ascorbate or placebo. Treatments will be administered daily for 12 weeks. Baseline assessments will measure airway and circulating antioxidant levels, inflammatory cells, lung function, respiratory symptoms, and methacholine reactivity. Allergy skin tests will also be performed to determine the state of atopy, which is a hereditary predisposition toward developing certain hypersensitivity reactions. Following baseline assessments, lung assessments will be conducted weekly for 12 weeks, sputum and blood samples will be collected bi-weekly, and methacholine reactivity will be assessed at Weeks 6 and 12.