ABSTRACT
Objective To study the influence of different intensities of treadmill exercise training on bone biomechanical properties and the bone healing in type 2 diabetic model rats.Methods Fifty-two healthy 8-month-old male Sprague-Dawley rats were randomly divided into a control group (n =10) and a type 2 diabetic model group (n =42).Type 2 diabetes was modeled in rats of the model group by feeding feedstuff containing high glucose,fat and energy food for 4weeks,followed by a single intra-abdominal injection of streptozotocin.Thirty model rats were then randomized into 3 subgroups:type 2 diabetes group,a mild exercise group and a moderate exercise group.Different intensities of treadmill training protocols was administered accordingly for 8 weeks.The biomechanical indices of the femur bone including maximum load and stress,module and energy was measured with mechanical testing instrument.Results Compared with the control group,both maximum load and energy were decreased significantly in type2 diabetes group [(148.5±17.8)N vs (192.3±43.4)N] for maximum load,and (51.38 ±13.7)mJ vs (82.0 ± 30.8) mJ for maximum stress] (P ＜ 0.05,P ＜ 0.01).Compared with the type 2 diabetes group,maximum load and stress were increased significantly in the mild and moderate exercise groups(P ＜ 0.05,P ＜ 0.01).Maximum load and energy were improved more in the moderate exercise group than in the mild exercise group [(184.1 ± 26.6)N vs (165.4±21.5)N for maximum load and (83.59 ±29.96)mJ vs (62.33 ±14.32)mJ for maximum stress] (P ＜ 0.05).Conclusions A significant decrease of the bone biomechanical properties was observed in rats with experimental type 2 diabetes,which could be alleviated by treadmill exercise training.
ABSTRACT
Objective To determine the influence of aerobic exercise on advanced glycation end products (AGEs)in plasma using a rat model of type 2 diabetes,and to provide an experimental basis for explaining the rehabilitative mechanism of aerobic exercise in type 2 diabetes.Methods Fifty-two healthy 8-week-old male SpragueDawley rats were allocated at random into a normal control group(n=10)and a type 2 diabetes model group(n=42).The latter were overfed with a high-sugar,high-fat and high-energy diet for 4 weeks,then 30ms/kg of streptozotocin was injected intraperitoneally to create a model of type 2 diabetes.Thirty diabetic rats were then allocated at random into a diabetes control group,a low intensity exercise group and a moderate intensity exercise group with 10 in each group.The treadmill exercise was administered to the animals in the low and moderate exercise groups accordingly.Results Compared with the normal control group,plasma AGEs increased significantly in the diabetes control and moderate intensity exercise groups.Compared with the diabetes control group,AGEs in the lower intensity exercise group were significantly lower.Compared with the moderate intensity exercise group,plasma AGEs in the low intensity exercise group were somewhat lower,but not significantly.Conclusion Aerobic exercise can reduce plasma AGE levels in rats with a model of type 2 diabetes.The effect is probably related to decreasing excessive blood glncose and the exercise intensity.