Omega-3 polyunsaturated fatty acids and immunosenescence

Abstract

It is well known that omega-3 (ω-3) polyunsaturated fatty acids (PUFAs) are considered anti-inflammatory while omega-6 polyunsaturated fatty acids are proinflammatory. Research elucidating the mechanisms of ω-3 PUFA actions has focused largely on the T-cell. ω-3 PUFA have been shown to regulate the balance of T-cell subsets as well as the intracellular signaling pathways regulating T-cell proliferation. This results in the suppression of proinflammatory cytokines like interleukin-2 and interferon gamma in models of increased inflammation. ω-3 PUFA have also been shown to modulate T-cell function indirectly by influencing the ability of key antigen presenting cells like macrophages and dendritic cells to provide the necessary activating signals to T-cells and other immune cells. Interestingly, in the few models of immunosuppression that have been studied, ω-3 PUFA seems to increase immune function bringing the response to near normal levels. One key area where very few studies have been performed is the impact of ω-3 PUFA on the aging immune system. The important point to keep in mind in general is that regardless of the mechanisms, ω-3 PUFA feeding or supplementation has not been shown to have any clear deleterious effects in short-term (less than 6 months) studies.