| Certain dietary fibers and indigestible oligosaccharides have been shown to lower circulating cholesterol and triacylglycerol levels, as well as induce anti-inflammatory effects in both animal models and humans. For example, psyllium fiber composed of a highly branched arabinoxylan has been shown to alter lipid metabolism. Furthermore, partially hydrolyzed arabinoxylan from rice bran significantly suppresses inflammation. However, we have limited understanding of how these dietary fibers and indigestible oligosaccharides regulate molecular events at the gene and protein level and influence energy metabolism as well as inflammatory events. To clarify the mechanism, we investigated the gene expression profile of liver and skeletal muscle of psyllium-treated obese mice using DNA microarrays. The results from our study suggest that psyllium stimulates the transfer of excess fatty acid from the liver to the skeletal muscle, where fatty acid oxidation is increased. These actions resulted in decreased lipid deposition in liver, skeletal muscle and visceral fat. Partially hydrolyzed arabinoxylan from rice bran is known to have a suppressive effect of D-galactosamin-induced hepatitis in animal models. We showed that this protective mechanism is mediated in part by suppress of interleukin-18 and by inhibition of CD14, NFκB, and JNK phosphorylation expression. Key ward : psyllium, rice bran, arabinoxylan, DNA microarray, obese, inflammation |
