Influence of Dietary Fish Oil on Granulomatous Inflammation in the Lung Following Inhalation of Silica and Infection with Bacillus Calmelte-Guerin

AbstractRecent evidence has suggested that fish oil diets, in addition to purported beneficial effects on the cardiovascular system, may also act to modulate inflammatory and immunologic reactions. These actions may be due to an increased content in fish oils of the n-3 fatty acid, eicosapentaenoic acid, which can competitively inhibit the production of arachidonic acid metabolites, forming 3-series prostaglandins and 5-series leukotrienes. In many cases these metabolites are not as biologically active as those formed from arachidonic acid. We examined the effects of dietary fish oil on granu-lomatous lesion development, pulmonary adherent cell (macrophage) activity, and arachidonic acid metabolite production following a regimen of silica inhalation and infection with Bacillus Calmette-Guerin (BCG). Mice on diets containing 10% corn oil or a mixture of 9% fish and 1% corn oils were placed in silica inhalation chambers for 6 wk, infected with BCG, and returned to inhalation chambers. Control animals, on ei...