Poster Topical Area: Nutrient-Gene Interactions
Location: Hall D
Poster Board Number: 453
Objective: Starvation or long-term intravenous nutrition reduce the function of the small intestine by reduction of villus height and a weight of gastrointestinal mucosa along with reduced expression of digestion and absorption related genes. Butyrate is known to inhibit histone deacetylases, and it is likely that butyrate promotes histone acetylation around the gene related digestion/absorption and induce the gene expression in the small intestine. In this study, we have investigated the effects of re-feeding a diet containing sodium butyrate after starvation on the induction of disaccharidase genes in the jejunum of rats.
Method: Six-week-old SD male rats were fasted for 3 days and re-fed a high-sucrose diet (control) or a high sucrose diet containing 5% sodium butyrate for 12 or 24 h. The mRNA expression levels of disaccharidase genes were measured by real time RT-PCR, and the amount of histone acetylation around the sucrase-isomaltase (Si) gene and lactase-phlorizin hydrolase (Lph) gene, and the bindings an acetylated histone binding protein BRD4, transcription elongation factor CDK9 and Cyclin T1 were measured by chromatin immunoprecipitation.
Results: Starvation for 3 days significantly decreased the histone H4 acetylation levels, and the binding levels of BRD4 and CDK9 around the Si and Lph genes. Re-feeding a diet containing butyrate for 12 hours led to an increase in the mRNA expression levels of Si and Lph. Re-feeding a diet containing butyrate for 24 hours significantly increased the bindings of BRD4 and CDK9 around the Si and Lph genes compared with the control.
Conclusion: Re-feeding a diet containing butyrate enhances the expression of Si and Lph genes though increasing the acetylation of histone H3 and binding levels of the transcription elongation factor around the Si and Lph genes.
University of Shizuoka
Shizuoka, Shizuoka, Japan