Conjugated linoleic acid can prevent tumor necrosis factor gene expression by inhibiting nuclear factor binding activity in peripheral blood mononuclear cells from weaned pigs challenged with lipopolysaccharide

Abstract

Twenty-four weanling barrows were fed corn-soybean diets supplemented with 2% conjugated linolenic acid (CLA) or soybean oil. On day 14 and 21, pigs were injected intraperitoneally with lipopolysaccharide (LPS) or sterile saline. Plasma samples were collected 2 h after injection. Peripheral blood mononuclear cells (PBMC) were also collected on day 21, 2 h after injection to determine tumor necrosis factor-α (TNF-α) production and its mRNA expression. The results indicate that dietary CLA inhibited the production of TNF-α by pig PBMC both at the protein and mRNA expression level. In a second experiment, PBMC, collected from a healthy pig, were incubated with either c9,t11-CLA or t10,c12-CLA, or without CLA and stimulated with LPS. Both CLA isomers inhibited LPS-stimulated TNF-α production and expression, which may be partially due to inhibition of the binding activity of nuclear factor-κB. The t10,c12 isomer was more effective than the c9,t11-CLA isomer in reducing TNF-α levels and nuclear factor-κB activation.