Effect of dietary carbohydrate source on the development of obesity in agouti transgenic mice.
OBJECTIVE
Our objective was to evaluate the effects of a qualitative change in dietary carbohydrate source on body weight and adiposity in a rodent model of diet-induced obesity.


METHODS
We evaluated the effects of high-fat diets (basal) varying in carbohydrate source in aP2-agouti transgenic mice. In the ad libitum study, animals were given free access to the basal diet or one of four test diets for 6 weeks. In two of the diets, dietary carbohydrate was derived from a single source: mung bean noodles (MUNG) or rolled oats (ROLL). The remaining diets were designed to mimic commercially available instant oatmeal with added sugar (IO-S) or flavored instant oatmeal (IO-F). In the energy-restricted study, animals were given ad libitum access to the basal diet for 6 weeks. Subsequently, animals were assigned to one of six treatment groups for 6 weeks. One group was continued on the basal diet ad libitum. The remaining groups were maintained with energy restriction (70% ad libitum) on either the basal, MUNG, ROLL, IO-S, or IO-F diet.


RESULTS
Subcutaneous fat pad mass was significantly higher (p<0.05) in the energy-restricted basal and IO-S groups compared with the energy-restricted ROLL diet. Similarly, visceral fat pad mass was significantly lower with ROLL and MUNG diets (p<0.05 for both) compared with basal and IO-S diets, and the insulin:glucose ratio was reduced (by 23% to 34%, p<0.05) in these two diets compared with all others. In ad libitum-fed animals, liver fatty acid synthase expression was 43% to 62% lower (p<0.05) with ROLL and MUNG diets compared with all others.


CONCLUSIONS
These data suggest that a qualitative change in dietary carbohydrate source modulates body weight and adiposity.
Morris
Kristin L
KL
Department of Nutrition, University of Tennessee, Room 229 Jessie Harris Building, 1215 West Cumberland Avenue, Knoxville, TN 37996, USA.
Zemel
Michael B
MB
D000273:Adipose Tissue / Q000378:metabolism*; D054366:Agouti Signaling Protein; D000818:Animals; D018554:Avena / Q000378:metabolism; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000502:physiology; D002352:Carrier Proteins / Q000378:metabolism; D004040:Dietary Carbohydrates / Q000378:metabolism*; D002149:Energy Intake / Q000502:physiology; D007887:Fabaceae / Q000378:metabolism; D064429:Fatty Acid Synthases / Q000235:genetics / Q000378:metabolism; D050556:Fatty Acid-Binding Proteins; D005508:Food Deprivation / Q000502:physiology; D007328:Insulin / Q000097:blood; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism; D020738:Leptin / Q000097:blood; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D009765:Obesity / Q000378:metabolism*; D009929:Organ Size; D014280:Triglycerides / Q000097:blood
D054366:Agouti Signaling Protein; D001786:Blood Glucose; D002352:Carrier Proteins; D004040:Dietary Carbohydrates; D050556:Fatty Acid-Binding Proteins; D007328:Insulin; D036341:Intercellular Signaling Peptides and Proteins; D020738:Leptin; D014280:Triglycerides; D064429:Fatty Acid Synthases