Flax seed oil protection from bleomycin‐induced lung vascular damage: a rat model

Abstract

Bleomycin, a widely used antineoplastic agent has been associated with severe pulmonary toxicity through production of acute interstitial pneumonia, pulmonary vasculitis and, eventually pulmonary fibrosis. Treatment by omega‐3 fatty acid in flax seed oil may reduce bleomycin induced lung injury. To test this hypothesis 72 rats were equally divided between diets receiving 15% fat as flax seed oil or corn oil (control). These two groups were further divided to receive either 8 units/kg body weight bleomycin or vehicle, intratracheally. Lungs were harvested at 2, 7, or 21 days and tissue was fixed and stained (H&E) for histopathology. Two investigators evaluated the bleomycin induced lung responses particularly the bleomycin‐induced pulmonary vasculitis by photographing five small caliber pulmonary arteries. These arteries were measured for pulmonary lumen patency and the ratio of media diameter/adventitia diameter. At days 7 and 21, bleomycin produced a significant reduction in lumen patency (p=0.01) and of media/adventitial diameter (p=0.02 all days) which was not evident when the rats were treated with the flax seed oil diet. At day 7 the flax seed oil group also showed a delay in edema formation, inflammatory cell infiltrate and reduced pulmonary septal thickness. This model presents a dietary regime which may protect against bleomycin pulmonary toxicity.Support: Wheaton College General Endowment fund.