The Effect of n-3 LCPUFA on Immune Function and Cardiovascular Risk Factors

The purpose of this study is to investigate the effects of long-chain n-3 polyunsaturated fatty acids (n-3 LCPUFA) on immune function and cardiovascular disease risk

In a controlled, double-blinded human intervention study the effects of fish oil versus control (olive oil) and of a high versus low consumption of n-6 polyunsaturated fatty acids are investigated. Sixty-seventy healthy men will be randomized to oil capsules and to substitute their dietary fats with one of two types of oil and butter-product that we provide. Outcome variables are ex vivo cytokine production in full blood and isolated immune cells after 24 h of stimulation with bacteria or bacterial components, blood pressure and arterial function, plasma concentrations of cholesterol, triacylglycerol, C-reactive protein and a number of other markers of endothelial function and cardiovascular risk. The hypotheses are that both increased intake of n-3 polyunsaturated fatty acids (from fish oil) and a low consumption of n-6 polyunsaturated fatty acids increase incorporation of docosahexanoic acid in immune cell membranes and that this decreases the inflammatory response and potential and improve overall cardiovascular disease risk. The mechanistic aspects of this will be further explored by in vitro studies with monocytes cultured in the presence of varying amounts of polyunsaturated fatty acids.

Fish oil, Polyunsaturated fatty acid, Immune function, Endothelial function, Cardiovascular risk factors

Ex vivo cytokine production (e.g. IL-6, TNF-α, IL-10, and interferon-γ) in whole blood and PBMC cultures after 24 h of stimulation - before and after interventions and after follow up

Plasma markers of endothelial function (e.g. VCAM-1, ICAM-1, Matrix metallo proteinases, E- & P-selectin, nitrite and endothelin-1) - before and after

Inclusion Criteria: Healthy (no chronic diseases and no regular medications) BMI >18.5 and <27.5 kg/m2 Daily use of fats and home cooking >5 d/wk Heavy exercise <7 h/wk Not daily smokers (<5 cigarets/wk) Exclusion Criteria:

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