Sex differences in postprandial plasma tumor necrosis factor-alpha, interleukin-6, and C-reactive protein concentrations

Abstract

Abdominal obesity and insulin resistance are characterized by low-level chronic inflammation most likely implicated in the increased cardiovascular disease risk associated with these conditions. However, not much is known of the acute regulation of circulating inflammatory markers in response to food intake. The aim of this study is to examine changes in inflammatory marker concentrations after the consumption of a high-fat meal in men and women. We measured tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and C-reactive protein concentrations in plasma samples collected at 0, 4, and 8 hours after consumption of the meal in 39 men and 41 women. Associations between these variations and physical as well as metabolic variables were then examined. We noted significant increases in plasma IL-6 concentrations at 4 and 8 hours after the meal in men (+34% and +107%, respectively; P < .005 vs 0 hour) and women (+78% and +153%, respectively; P < .0001 vs 0 hour). Postprandial plasma TNF-alpha concentrations significantly dropped at 4 hours after the high-fat meal in men (-9.5%, P < .0005 vs 0 hour) and women (-5.5%, P < .05 vs 0 hour). Plasma CRP concentrations were not affected by food intake in either men or women. We also found that postprandial plasma concentrations of IL-6 were lower in subjects with a normal glucose tolerance (n = 69) compared with individuals with an impaired glucose tolerance (n = 11). Results of the present study show that consumption of a high-fat meal is associated with a transient reduction in circulating concentrations of TNF-alpha in both men and women as well as an elevation of plasma IL-6 concentrations that was found to be greater in women than in men.