Study Of Dietary Fibre's Hypoglycemic Effect On Type 2 Diabetes Mellitus Rats And Its Mechanism

Diabetes has become the third largest non-communicable diseases, second only to cardiovascular disease and cancer, to find a feasible method of treatment of diabetes is of great significance. It is the global hygine issue. Dietary fiber has unique physical and chemical properties and other physiological functions, have been reported with hypoglycemic effects. Possible mechanisms include the gel fiber itself, increase the body's sensitivity to insulin, increase satiety and inhibit digestive enzymes and increase insulin receptor cells.The topics established the type 2 diabetes rat models induced by nicotinamide-streptozotocin gender. Through comparing different genders and body weights of SD rats, the optimal modeling condition was obtained. Different fibers, including soluble dietary fiber, insoluble dietary fiber and total dietary fiber were selected to study their effects on blood glucose, and from the glycated hemoglobin, glucose tolerance, liver glycogen and other aspects to analyze the possible mechanism of lowering blood glucose in vivo. Dietary fiber in vitro possible hypoglycemic mechanism was studied as well:by comparing the fibers'inhibition on the a-glucosidase activity, and thus to study the hypoglycemic mechanism.We achieved relatively optimal condition to establish the type 2 diabetes model. The conditions are as follows:male SD rats with 220g body weight. Because models established by female rats or ones with other body weight range are unstable and relatively bad rate of success. Male rats with 220g body weight may be more sensitive to the streptozotocin, and its body's condition is the most suitable for modeling.Effects of dietary fiber on blood glucose in diabetic rats and its hypoglycemic Mechanism:①Effect on fasting blood glucose:From fasting plasma glucose and glycated hemoglobin can be seen that dietary fiber can reduce blood glucose levels in diabetic rats. In the study of fasting blood glucose, the order of hypoglycemic effect of these materials are insoluble dietary fiber> total dietary fiber> soluble dietary fiber> acarbose; and in glycated hemoglobin, decreasing effect of acarbose> insoluble dietary fiber> total dietary fiber> soluble dietary fiber.②Mechanism in vivo:From the oral glucose tolerance and glycosylated hemoglobin test results we can concluded, the hypoglycemic effect of dietary fiber may come from its stimulation of insulin secretion。In the oral glucose tolerance test, the allevating effect order is insoluble dietary fiber> total dietary fiber> soluble dietary fiber;From the glycogen test results can draw a conclusion, which dietary fiber may lower blood sugar from its activation of glycogen synthesis, increased synthesis of glycogen, and reducing the role of glycogen gluconeogenesis. The result is, acarbose tablets> insoluble dietary fiber slightly> total dietary fiber> soluble dietary fiber.The body weight results showed that dietary fiber can also be due to muscle protective effects of the excessive consumption in diabetic rats, the dietary fiber can be have a stable effect on body weight. One control group, soluble dietary fiber and in acarbose group, the body weight change similarly, while in insoluble dietary fiber group, the weight gains slightly faster.From in vivo experiments can be drawn hypoglycemic, dietary fiber may lower blood sugar the body from its stimulation of insulin, increase insulin sensitivity and stimulate glycogen synthesis, inhibition of gluconeogenesis, thereby to control fasting blood glucose and glycosylated The role of hemoglobin, ultimately lowering blood glucose levels in diabetic rats.Lowering blood glucose mechanism in vitro, the value of the alpha-glucosidase inhibition rate of dietary fibers was studied, inhibitory activity of acarbose was the highest one with 65.93%, total dietary fiber and a single fiber group is very close to 43%. Insoluble dietary fiber group is slightly higher than the inhibitory activity of soluble dietary fiber group, but the difference is small.In brief, dietary fiber can lower the glucose levels, and among the three dietary fibers, the insoluble dietary fiber has relatively better function than the other two dietary fibers. Its main glucose lowering mechanism may due to it stimulation of insulin secretion, inhibitory of alpha-glucosidase, activation of the glycogen synthesis process, diminishment of the fasting glucose levels and glycolated hemoglobin levels.