Effect of trans-10, cis-12 Conjugated Linoleic Acid on Calcium-Dependent Reactive Oxygen Species and Nitric Oxide Production and Nuclear Factor-${kappa}B$ Activation in Lipopolysaccharide-Stimulated RAW 264.7 Cells

Abstract

Trans-10, cis-12-conjugated linoleic acid (t10c12-CLA) has been shown to participate in the regulation of anti-inflammatory effects. The objectives of this study were to examine the effects of t10c12-CLA on reactive oxygen species (ROS) and nitric oxide (NO) production and nuclear factor-kappaB (NF-κB) activation in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and to determine whether these effects were associated with change of intracellular calcium ion (Ca 2+ ). ROS production was increased in LPS-stimulated RAW 264.7 cells, and this effect was suppressed by 1,2-bis-(o-aminophenoxy) ethane-N,N,N,N-tetraacetic acid-acetoxymethyl ester (BAPTA/AM), a calcium chelator. t10c12-CLA suppressed ROS production in LPS-stimulated RAW 264.7 cells, which was further more decreased by treatment with BAPTA/AM. These indicated that t10c12-CLA decreases Ca 2+ -dependent ROS production in LPSstimulated RAW 264.7 cells. Similarly, NF-κB p65 DNA binding activity and NO production were decreased by treatment with either t10c12-CLA, BAPTA/AM, or t10c12-CLA and BAPTA/AM combination. However, there were no differences between t10c12-CLA and BAPTA/AM treatment in NO production of LPS-stimulated RAW 264.7 cells. These data indicate that t10c12-CLA inhibits the increases in ROS and NO production and the NF-κB activation in LPS-stimulated condition. These results suggested that CLA exerts potent anti-inflammatory effects by suppression of LPS-induced ROS and NO production, and NF-κB activationn via Ca 2+ -dependent pathway.