Abstract
Aim: Formula diet (FD), which is used as a tool for calorie restriction, has beneficial effects on metabolic disorders in obese patients; however, the molecular mechanism is not fully understood.
Methods: Sixteen-week-old male Zucker Diabetic Fatty (ZDF) rats were divided into 3 groups (n= 10 each): calorie-controlled low-fat diet [Control; 75 kcal/day, protein : fat : carbohydrate (P:F:C)=25:15: 60], calorie-restricted low-fat diet (CR-LFD; 56 kcal/day, P:F:C=25:15:60), and calorie-restricted FD (CR-FD; 56 kcal/day, P:F:C=50:14:36) group, and fed each diet for 4 weeks. Before the study, baseline data were obtained in 10 rats. After 4 weeks, body weight and epididymal fat weight were measured, and blood samples, mesenteric and subcutaneous adipose tissues were collected for analyses. Messenger RNA expression was evaluated by real-time PCR, and protein expression by Western blotting.
Results: The decrease in epididymal fat weight was significantly greater in the CR-FD group than in control and CR-LFD groups, although changes in body weight were not different among groups. The decrease in fasting plasma glucose and increase in plasma adiponectin were greater in the CR-FD group than in the control group, but not in the CR-LFD group. The decrease in triglyceride and increase in HDL-cholesterol were greatest in the CR-FD group. Both mRNA and protein of peroxisome proliferator-activated receptor γ coactivator (PGC)-1α, adiponectin, lipoprotein lipase and PPARγ were overexpressed in the CR-FD group, especially in mesenteric adipose tissue.
Conclusions: FD may have beneficial effects on abdominal obesity and metabolic disorders by reducing visceral fat and improving glucose and lipid profiles, possibly through modulating adipose tissue function.Key words; Formula diet, High protein diet, Low carbohydrate diet, Obesity, Zucker diabetic fatty rat
