To Study the Effect of High Fat High Carbohydrate Meal on Oxidative Load, Inflammatory Mediators and Insulin Resistance in Normal and Obese Subjects

The main objective of this research is to investigate the effect of high fat high carbohydrate (HFHC) meal on inflammatory mechanisms at the molecular level in humans, in vivo versus HFHC meal plus fiber. HFHC meal includes egg muffin, sausage muffin sandwiches and two hash browns. The Investigators have previously shown that the intake of one HFHC meal leads to an increase in reactive oxygen species (ROS) generation and the expression of p47, the key subunit of NADPH oxidase, with a concomitant increase in intranuclear nuclear factor κB (NFkB) binding. More recently, the investigators have also shown that HFHC meal leads to an increase in plasma endotoxin (lipopolysaccharide, LPS) concentrations along with an increase in the expression of Toll like receptor-4 (TLR-4), the receptor for endotoxin, and TLR-2, the receptor for several products of Gram positive bacteria. In addition, it also causes an increase in lipopolysaccharide binding protein (LBP), the protein which facilitates the binding of LPS to CD14 and TLR-4. Finally, HFHC meal also induces an increase in the expression of suppressor of cytokine signaling- 3 (SOCS-3) in the mononuclear cells (MNC) (1), which interferes with insulin signal transduction and contributes to the pathogenesis of insulin resistance. In contrast, an AHA meal does not induce these effects. These observations are important since HFHC meal not only induces oxidative stress and inflammation but also lays the foundations of (2) a potentially greater response to an inflammatory challenge through the induction of an increase in LPS concentrations and the expression of TLR-4 and TLR-2; and (3) insulin resistance through the induction of SOCS-3, TLR-4 and TLR-2.