Effect of a single high-fat meal on endothelial function in patients with the metabolic syndrome: Role of tumor necrosis factor-α

Abstract

Background and aims A single high-fat meal may induce endothelial activation and dysfunction in both normal subjects and in patients with type 2 diabetes. The aim of this study was to assess the effect of a high-fat meal on endothelial function in patients with the metabolic syndrome. Methods and results Twenty-five patients with the metabolic syndrome (ATP III criteria) were matched for sex, age and body mass index with 25 subjects without the metabolic syndrome. All subjects ate under supervision a high fat meal (760 calories) with 59% energy from fat, 12% energy from protein and 29% energy from carbohydrates. Compared with the control group, subjects with the metabolic syndrome had reduced endothelial function, as assessed with the l-arginine test, and higher circulating levels of TNF-α. Following the high-fat meal, both triglyceride and TNF-α levels increased more in subjects with the metabolic syndrome than in subjects without, while endothelial function decreased more in subjects with the metabolic syndrome. There was a significant relation between increases in TNF-α levels and decreases in endothelial function score in subjects with the metabolic syndrome ( r = −0.39, P = 0.03). Conclusion TNF-α levels are increased in subjects with the metabolic syndrome; moreover, a high-fat meal produces further increase in its levels associated with endothelial dysfunction.