Polyunsaturated fatty acids, inflammation, and immunity.

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Polyunsaturated fatty acids, inflammation, and immunity.

Calder PC.

Institute of Human Nutrition, University of Southampton, Southampton

5016 7PX, United Kingdom. pcc@...

The fatty acid composition of inflammatory and immune cells is sensitive

to change according to the fatty acid composition of the diet. In

particular, the proportion of different types of polyunsaturated fatty

acids (PUFA) in these cells is readily changed, and this provides a link

between dietary PUFA intake, inflammation, and immunity. The n-6 PUFA

arachidonic acid (AA) is the precursor of prostaglandins, leukotrienes,

and related compounds, which have important roles in inflammation and in

the regulation of immunity. Fish oil contains the n-3 PUFA

eicosapentaenoic acid (EPA). Feeding fish oil results in partial

replacement of AA in cell membranes by EPA. This leads to decreased

production of AA-derived mediators. In addition, EPA is a substrate for

cyclooxygenase and lipoxygenase and gives rise to mediators that often

have different biological actions or potencies than those formed from

AA. Animal studies have shown that dietary fish oil results in altered

lymphocyte function and in suppressed production of proinflammatory

cytokines by macrophages. Supplementation of the diet of healthy human

volunteers with fish oil-derived n-3 PUFA results in decreased monocyte

and neutrophil chemotaxis and decreased production of proinflammatory

cytokines. Fish oil feeding has been shown to ameliorate the symptoms of

some animal models of autoimmune disease. Clinical studies have reported

that fish oil supplementation has beneficial effects in rheumatoid

arthritis, inflammatory bowel disease, and among some asthmatics,

supporting the idea that the n-3 PUFA in fish oil are anti-inflammatory

and immunomodulatory.

PMID: 11724453 [PubMed - in process]