Butter and walnuts, but not olive oil, elicit postprandial activation of nuclear transcription factor KB in peripheral blood mononuclear cells from healthy men

Background: Nuclear transcription factor kappaB (NF-kappaB) plays an important role in atherosclerosis by modulating gene expression. Postprandial lipemia has been correlated with an increase in NF-kappaB activation in vascular cells and it is associated with an increase in postprandial triacylglycerol-rich lipoproteins, which are involved in the development of atherosclerotic plaque. Objective: The objective of this study was to determine the effect of the intakes of 3 different foods with different fat compositions on the postprandial activation of monocyte NF-kappaB. Design: Eight healthy men followed a 4-wk baseline diet and then consumed 3 fat-load meals consisting of 1 g fat/kg body wt (65% fat) according to a randomized crossover design. Each meal had a different fatty acid composition, and the consumption of each meal was separated by 1 wk. The compositions of the 3 test meals were as follows: olive oil meal [22% saturated fatty acids (SFAs), 38% monounsaturated fatty acids (MUFAs), 4% polyunsaturated fatty acids (PUFAs), and 0.7% a-linolenic acid], butter meal (38% SFAs, 22% MUFAs, 4% PUFAs, and 0.7% a-linolenic acid), and walnut meal (20% SFAs, 24% MUFAs, 16% PUFAs, and 4% a-linolenic acid). Results: Ingestion of the olive oil meal did not elicit NF-KB activation compared with ingestion of either the butter meal at 3 h (P < 0.05) or the walnut meal at 9 h (P < 0.05). There was no significant difference in the postprandial triacylglycerol response between the 3 meals. Conclusions: Consumption of an olive oil-enriched meal does not activate NF-KB in monocytes as do butter and walnut-enriched meals. This effect could enhance the cardioprotective effect of olive oil-enriched diets.