Activity of the leukocyte NADPH oxidase in whole neutrophils and cell-freeneutrophil preparations stimulated with long-chain polyunsaturated fatty acids

Fish oils are known for their anti-inflammatory effects. In this paper we i nvestigated the influence of eicosapentacnoic acid and docosahexaenoic acid (omega -3 fatty acids), as well as docosapentaenoic acid, a metabolic prod uct of omega -3 fatty acid metabolism, on O-2(-)-production catalyzed by th e NADPH oxidase in whole neutrophils and in a cell-free system consisting o f neutrophil membranes and cytosol. As a standard we used arachidonic acid (an omega -6 fatty acid) found in a high proportion in the Western diet, an d known as an effective activator of the oxidase in both systems. Our data show that with omega -3 fatty acids, the O-2(-)-production in both systems is reduced as compared to the effect of arachidonic acid. The effects are m ore pronounced with increasing carbon chain length and increasing numbers o f double bonds. Our results suggest another mechanism besides the inhibitio n of eicosanoid and cytokine production to explain the beneficial effects o f fish oils in reducing inflammation.