VITAMIN-E METABOLISM OF THE LUNG

Experimental and clinical data have provided evidence for the involvem ent of oxygen free radicals in the development of acute and chronic lu ng diseases. Alveolar surfactant is the prime target of oxidative air pollutants. Lung surfactant consists to 90% of lipids and contains vit amin E as most important lipophilic antioxidant. Recently, we showed t hat alveolar surfactant is supplemented with vitamin E during its synt hesis in type II pneumocytes. Hyperoxia is very often a necessary ther apeutic intervention which seems to impose oxidative stress on lung ti ssue. Hyperoxia caused an increase in vitamin E turnover, measured in type II pneumocytes, lamellar bodies and lung lavages. In contrast, th e turnover of surfactant cholesterol and surfactant lipids does not ch ange. Hyperoxia caused an increase in vitamin E uptake by type II pneu mocytes and an enrichment of vitamin E in lamellar bodies.