Modulating Effect of Sesamin, a Functional Lignan in Sesame Seeds, on the Transcription Levels of Lipid- and Alcohol-Metabolizing Enzymes in Rat Liver: A DNA Microarray Study

Sesamin, a major lignan in sesame seeds, has multiple functions such as cholesterol-lowering and anti-hypertensive activities. To investigate the effect of sesamin on gene expression in the liver, a DNA microarray analysis was carried out. The ingestion of sesamin dissolved in olive oil up-regulated the expression of 38 genes, 16 of which encode proteins possessing a lipid-metabolizing function, and 16 of which encode proteins possessing a xenobiotic/endogenous substance metabolizing function. In particular, sesamin significantly increased the expression of beta-oxidation-associated enzymes in peroxisomes and auxiliary enzymes required for degradation, via the beta-oxidation pathway, of unsaturated fatty acids in mitochondria. The ingestion of sesamin also resulted in an increase in the gene expression of acyl-CoA thioesterase involved in acyl-CoA hydrolase and very-long-chain acyl-CoA thioesterase. Interestingly, it induced the expression of the gene for aldehyde dehydrogenase, an alcohol-metabolizing enzyme. These results suggest that sesamin regulates the metabolism of lipids, xenobiotics, and alcohol at the mRNA level.