Abstract 706: HDL and ApoA-I Inhibit Palmitate-induced Lipid Raft Trafficking of TLR4 and Inflammatory Cytokines Expression in Adipocytes

Background: Adipose tissue inflammation induces inflammatory molecules production leading to insulin resistance and increased cardiovascular disease risk. Recently it has become apparent that innate immune system is activated by saturated fatty acids (SFAs) by a process involved in TLR4 signaling. HDL and apoA-I has anti-inflammatory effects, however the mechanisms are not well understood in adipocytes. Aims: We examined to elucidate the effect of HDL and/or ApoA-I mediated cholesterol efflux on induction of inflammatory gene expression by palmitate in adipocytes via TLR4 dependent immune system. Methods: 3T3-L1 adipocytes are exposure to 250uM palmitate for periods of up to 24 hours with or without HDL or Apo A-I. Antisense directed to ABCG-1 or ABCA-1 is added 24 hours prior to each reagent challenge. Cells were harvested and estimated for expression of Saa3 gene using real-time PCR or detection of TLR4 in raft or non raft by western blotting. Lipid rafts were purified by ultracentrifugation on disconti...