ABSTRACT
@#Introduction: We clarified the extent to which white rice (WR)-based carbohydrate diets affect body weight and metabolic parameters in rats. Methods: In this experimental study, a male Sprague Dawley (n=32) rats fed with WRbased CHO diet in two different proportions of total energy intake (TEI 55% moderate-CHO (MCHO, n=8) and 65% High-CHO (HCHO, n=8)) or high-fat diet (HFD, n=8) were compared with rats maintained on standard pellet diet (SD, n=8) for eight weeks period. Carbohydrate sources in the HFD and SD were mainly based on cornstarch (25% of amylose). Outcomes measures include body weight and metabolic parameters. Results: At baseline, body weight and metabolic parameters (fasting plasma glucose, insulin, and triglyceride levels) were comparable in all rats. Despite higher daily caloric intake in rats fed with HFD (103.9±3.0) than the other diets, no significant differences in body weight between groups after 8 weeks of study. However, rats’ feds with WR-based CHO diets (both moderate and high carbohydrates) had higher fasting blood glucose (MCHO=12.8±1.6, HCHO=16.9±2.4) and triglycerides level (MCHO=1.2±0.0, HCHO=1.3±0.0) than rats in cornstarch-based HFD and SD (p<0.05). Both HFD and HCHO had higher fasting insulin than MCHO and SD (p<0.05), but the homeostatic model assessment of insulin resistance (HOMA-IR) was significantly higher in WR-based CHO diets (both moderate and high carbohydrates) than the rats in cornstarch-based HFD and SD (p<0.05). Conclusion: A WR-based CHO diet exhibits higher fasting blood glucose, triglycerides, and insulin resistance state than a high-fat diet without a significant impact on body weight. These findings may explain the growing incidence of diabetes in Asia and worth studying further.
ABSTRACT
In this study, we explored the effects of long-term consumption of a high-sugar high-fat diet on glucose tolerance and insulin resistance in rats. Rats were fed with either standard rat chow diet (NC group) or high-sugar high-fat diet (HSHF group) for 16 weeks. The HSHF group showed significantly higher fasting insulin level than NC group. Following intraperitoneal glucose challenge, blood glucose and insulin levels in the NC and HSHF groups increased. However, the magnitude of the response in NC group was low compared to HSHF group. Insulin resistance was higher in HSHF group and insulin sensitivity decreased significantly (P <0.05) in HSHF group in contrast to NC group. Low-density lipoprotein-cholesterol (LDL-C) and triglyceride (TG)/high-density lipoprotein-cholesterol (HDL-C) levels showed significant increase in HSHF group, while triglyceride and total cholesterol levels did not show any difference. The study demonstrated that feeding high-sugar high-fat diet to the experimental Sprague-Dawley rats for 16 weeks increased possibility of insulin resistance in them but did not turn them hyperglycemic or diabetic. Thus, they prove to be a suitable animal model to explore various aspects of insulin resistance.