Effect of vitamin D deficiency on pathogenesis of Zucker diabetic fatty rat / 中国比较医学杂志

Objective To investigate the effect of vitamin D(VD)deficiency on the pathogenesis of Zucker diabetic fatty(ZDF)rats. Methods Male 5-6 weeks old Zucker rats were randomly divided into 4 groups according to their body weight:normal control group(ZL),VD deficient control group(ZL+VD.Def),model group(ZDF)and VD deficient model group(ZDF+VD.Def). All the rats were fed to 12 weeks of age, and body weight, food intake, water intake,urine volume,urine glucose,fasting blood glucose were measured. The glucose tolerance was tested at 11 weeks. Pancreatic samples were taken and tissue sections were examined by pathology using HE staining. Results The body weight of ZDF+VD.Def group was higher than that of the ZDF group. Drinking water and urine volume were increased earlier than the ZDF rats. The blood glucose in the ZDF +VD. Def group was increased significantly earlier than ZDF group,it is about 2 times of the ZDF group at 12 weeks. Compared with the ZDF group,the impaired glucose tolerance and islet damage were more serious than the ZDF + VD. Def group. Conclusions Vitamin D deficiency accelerates and aggravates the pathogenesis of ZDF rats,and VD deficiency may be a key factor in the pathogenesis of obese DM Type 2.

Pathophysiological Changes by Short-term Food Restriction in Obese Diabetic Rats.

Aim: Reduced calorie intake by food restriction leads to extension of life span by exerting beneficial effects on metabolism. Zucker diabetic fatty (ZDF) rat is a type 2 diabetic model with obesity, showing the incidence of diabetes after 7 weeks of age. The present study investigated effects of 2-week food restriction on the pancreas in ZDF rats. Methods: ZDF rats were pair-fed with Zucker lean (ZL) rats from 7 to 9 weeks of age (The amount of food in ZDF rats was calculated based on the daily food consumption in ZL rats). Body weight and biochemical parameters such as serum glucose, triglyceride, total cholesterol, non-esterified fatty acid and insulin levels, were evaluated. After necropsy, islet size and insulin content in pancreas were measured. Results: The ZDF rats showed increased blood glucose, insulin and lipid levels at 7 weeks as compared with those in ZL rats. After food restriction for 2 weeks, the blood glucose, insulin, and triglyceride levels in pair-fed ZDF rats were decreased. The islet size in pair-fed ZDF rats decreased as compared with that in ad lib-fed ZDF rats, but the insulin content in pancreas of pair-fed ZDF rats increased remarkably. Conclusion: ZDF rats showed improvement of pancreatic disorders by food restriction. Caloric restriction applied at an insulin resistant pre-diabetic stage is an effective means for preventing the pancreatic disorder in diabetes with obesity.