Location: Arkansas Children's Nutrition CenterTitle: A high carbohydrate diet coordinately alters transcriptomic profiles in the adipose tissue leading to enhanced lipid biosynthesis Author
Submitted to: Federation of American Societies for Experimental Biology Conference
Publication Type: Abstract Only
Publication Acceptance Date: 2/11/2009
Publication Date: 4/1/2009
Publication URL: http://www.fasebj.org.libproxy.uams.edu/content/vol23/1_MeetingAbstracts/aindex.shtml#A
Citation: Shankar, K., Harrell, A., Ronis, M.J., Badger, T.M. 2009. A high carbohydrate diet coordinately alters transcriptomic profiles in the adipose tissue leading to enhanced lipid biosynthesis [abstract]. FASEB J. 23(1_MeetingAbstracts):556.2. Interpretive Summary: As obesity continues to be one of the most important public health issues, the understanding of the how composition of our diets affects our ability to gain weight is becoming increasingly important. Our studies showed that overfeeding of diets high in carbohydrate or fat led to greater weight gain and body fat accumulation. Body composition analyses using CT scanning confirmed that increased body weight was due to fat accumulation. Using microarray technology, we analyzed the changes in gene expression in the adipose tissues of rats fed high carbohydrate diets. Our analyses revealed a large number of genes involved in regulating lipid biosynthesis to be directly regulated by carbohydrate from the diet. Data from our studies also suggest that dietary carbohydrates are able to significantly influence gene expression in the adipose tissue to enhance glucose breakdown and synthesis fat.
Technical Abstract: To assess the role of dietary macronutrient composition on adipose gene expression we evaluated changes in transcriptomic profiles in the WAT of rats following high carbohydrate (HC) diets. Female Sprague-Dawley rats received liquid diets at 187 or 220 kcal/kg3/4/d via intragastric infusion. Diets were either HC (75% carb calories) or high-fat (HF, 45% fat calories) and were infused 23 h/d for 3 wk. Rats fed HC diets gained greater body-weights and %body fat (p<0.05) than HF counterparts. Microarray analyses of retroperitoneal WAT using GeneSpring Gx7.3 revealed 581 transcripts were altered by HC at either 187 or 220 Kcal (+/-1.8-fold, p <0.05). Of these, 153 transcripts were altered by HC at both caloric intakes, indicating direct responsiveness to dietary carbohydrate. Specifically genes involved in glucose transport (GLUT4), glycolysis (HK2, ALDO2, Me1, ACLY, Pdh, OCD), fatty acid biosynthesis, elongation, and desaturation (FASN, SCD2, ACC1, ELOVL4, 5 and 6, FADS2, adiponutrin) were significantly up-regulated. Thirteen genes involved in cholesterol biosynthesis and transport were also induced by HC. Most interestingly, mRNA expression of ChRBEP was also induced in adipose tissue of HC rats. These data indicate carbohydrates transcriptionally regulate a diverse suite of genes involved in the entire pathway of lipid biosynthesis in the adipose tissue.