[Animal Modeling]-The effect of exercise on the islets of diabetic rats and its mechanism

  Objective: To investigate the effect of aerobic exercise on pancreatic islets and β cells in type 2 diabetic rats and its mechanism.

  Method: 30 Wistar rats, 10 were randomly selected as group C, and the remaining 20 rats were fed streptozotocin (STZ) and a high-fat and high-sugar diet to establish a type 2 diabetic rat model and maintain successful The 15 animals were divided into two groups, one was the DMC group (n = 7), and the other was the DME group (n = 7, at the end of the experiment, one animal died). The rats in the DME group exercised on a treadmill at an intensity of 20 m/min for 30 minutes, and rested for 8 weeks every 6 days. The remaining rats can move freely in the cage. At the end of the experiment, blood was drawn from the abdominal aorta to measure blood glucose and serum Ins content, and calculate HOMA. The first third of the pancreas was cut into paraffin sections, HE stained, and the islets and β morphology were measured. -Observe the cell structure with a digital microscope and take pictures; under a magnified field of view, use the MoticImagesAdvanced3.1 image processing software to measure the circumference and area of the pancreatic islets and calculate the SF; homogenize the rest of the pancreas and measure the Ins content, GK and trace total ATPase active.

  Results: Compared with the rats in the DMC group, the circumference and area of the islets in the DME group increased significantly (P\u003c0.05), but still lower than the rats in the C group and SF compared with the rats in the DMC group. β-cell hypertrophy, vacuoles and nuclear coagulation and contraction have been significantly improved. The blood glucose, Ins content, pancreatic GK and trace total ATPase activities of the DME group were significantly higher than those of the DMC group (P≥0.05); SF and HOMA also had significant changes.

  Conclusion: Aerobic exercise can reduce the blood glucose level of type 2 diabetic rats and improve the morphology and structure of pancreatic islets and pancreatic β-cells by improving pancreatic tissue GK, ATP synthase activity and insulin sensitivity.