Objective: Nuclear transcription factor kappaB (NF-kappaB) plays a key role in the inflammatory response and can be modulate by dietary fat. We have examined the effect of three diets, with different fat composition, on the activation of NF-kappaB on peripheral blood mononuclear cells (PBMCs).
Methods: Sixteen healthy men followed three 4-week diets, in a randomised crossover design: a Western diet, rich in saturated fat (SFA) [22% SFA, 12% monounsaturated fat (MUFA) and 0, 4 alpha-linolenic acid]; a Mediterranean diet [<10% SFA, 24% MUFA and 0.4% alpha-linolenic acid], and a low fat diet enriched in alpha-linolenic acid [<10% SFA, 12% MUFA and 2% alpha-linolenic acid]. NF-kappaB (electrophoretic mobility shift assay) in mononuclear cells and plasma concentrations (ELISA) of soluble vascular cellular adhesion molecule 1 (VCAM-1) were examined after either diets.
Results: Western diet increased 2.7-fold NF-kappaB compared with the Mediterranean diet (p=0.038) and 1.79-fold with the alpha-linolenic acid diet (p=0.07). No differences were found between the last two. Furthermore, an increase on plasma VCAM-1 was observed with the Western diet (p<0.05).
Conclusions: The Mediterranean diet diminished NF-kappaB activation in mononuclear cells, compared with Western diet, supporting its cardioprotective properties. The effect of the n-3 enriched diet was intermediate.