Egg intake increases peripheral blood mononuclear cell expression of ATP‐binding cassette transporter A1 in parallel with toll‐like receptor 4 as a potential mechanism to reduce cellular inflammation in metabolic syndrome

Abstract

We investigated the effects of excess dietary cholesterol from eggs on peripheral blood mononuclear cell (PBMC) expression of inflammatory mediators and HDL‐associated lipid transporters in metabolic syndrome (MetS). Thirty‐seven men and women consumed either 3 eggs (EGG, additional 534 mg of dietary cholesterol) or the equivalent amount of a cholesterol‐free egg substitute (SUB, 0 additional mg of cholesterol) in combination with a carbohydrate‐restricted diet for 12 weeks. All participants reduced body weight an average of 4.0 ¡Ó 2.8% with no difference between groups. While PBMC mRNA expression of tumor necrosis factor ƒÑ (TNF‐ƒÑ), interleukin 6 (IL‐6), and interleukin 1ƒÒ (IL‐1ƒÒ) did not change, toll‐like receptor 4 (TLR4) increased in EGG only (+75.3% vs. −6.2% in SUB). Changes in TLR4 expression were positively correlated with nuclear factor £eB (NF‐£eB) p65 DNA binding activity. ATP‐binding cassette transporter A1 (ABCA1) expression increased in EGG only (+127.0% vs. +31.5% in SUB) while ABCG1 did not change. Interestingly, changes in ABCA1 were positively correlated with changes in IL‐6, IL‐1ƒÒ, and TLR4 in EGG only, as were changes in ABCG1 and IL‐6 and IL‐1ƒÒ. These findings suggest that the increase in PBMC ABCA1 expression from egg intake is potentially due to an effort to reduce cellular inflammation in MetS. Supported by the American Egg Board and USDA Grant No. 2012–67011‐19914Grant Funding Source: USDA Grant No. 2012–67011‐19914