This study determined whether free radical formation by the liver, tumor necrosis factor (TNF)-α production by isolated Kupffer cells, and plasma endotoxin are affected by dietary saturated fat. Rats were fed enteral ethanol and corn oil (E-CO) or medium-chain triglycerides (E-MCT) and control rats received corn oil (C-CO) or medium-chain triglycerides (C-MCT) for 2 wk. E-CO rats developed moderate fatty infiltration and slight inflammation; however, E-MCT prevented liver injury. Serum aspartate aminotransferase levels, gut permeability, and plasma endotoxin doubled with E-CO but were blunted ∼50% with E-MCT. In Kupffer cells from E-CO rats, intracellular calcium was elevated by lipopolysaccharide (LPS) in a dose-dependent manner. In cells from E-MCT rats, increases were blunted by ∼40–50% at all concentrations of LPS. The LPS-induced increase in TNF-α production by Kupffer cells was dose dependent and was blunted by 40% by MCT. E-CO increased radical adducts and was reduced ∼50% by MCT. MCT prevent early alcohol-induced liver injury, in part, by inhibition of free radical formation and TNF-α production by inhibition of endotoxin-mediated activation of Kupffer cells.
Metabolic Effects in Lambs Intravenously Infused with Xylitol, Medium Chain Triglycerides, and Corn Oil
