Fish again for dinner! The role of fish and other dietary oils in the therapy of skin disease

Abstract

Adequate levels of polyunsaturated fatty acids are necessary for the normal functioning of most mammalian cells, both to provide fluidity to the cell membrane lipid bilayer and to function as precursors for the synthesis of the regulatory eicosanoids, prostaglandins, and leukotrienes. The omega-6 class of polyunsaturated fatty acids, such as linoleic and arachidonic acids, are of special importance as precursors for eicosanoid synthesis. The skin is a particularly good organ in which to study the effects of polyunsaturated fatty acids metabolism, inasmuch as either deficiencies of specific PUFA or overproduction of polyunsaturated fatty acids-derived prostaglandin and leukotriene result in specific, clinically recognizable cutaneous diseases. To help understand the pathogenesis of these diseases, polyunsaturated fatty acids metabolism is reviewed here, with emphasis on clinical manifestations of both deficiency syndromes and overproduction of proinflammatory eicosanoids. A rationale is presented for a therapeutic approach to inflammatory disease by dietary manipulation and substitution of omega-6 fatty acids by the unique omega- 3 class of polyunsaturated fatty acids found in fish. Evidence for the efficacy of fish oil in the therapy of specific inflammatory diseases is reviewed, as are the caveats regarding its therapeutic use. Dietary manipulations, specifically fish oil additives, appear to hold promise as therapeutic tools for cutaneous diseases.