罗格列酮对糖尿病大鼠残存胰岛β细胞的保护作用

Protective effects of rosiglitazone treatment on the survival pancreatic beta cells of diabetic rats

目的观察罗格列酮(RSG)对糖尿病大鼠残存胰岛β细胞功能的影响。方法SD大鼠48只随机分为3组,正常对照(NC)组8只,糖尿病对照(DM)组20只,罗格列酮干预(RSG)组20只。DM、RSG两组成模糖尿病大鼠,RSG组即以罗格列酮灌胃(5mg·kg-1·d-1),此后1、2、4、7、10周时,分别测定各组的FBG和FIns,DM、RSG两组分别在每个时间点各处死动物4只。透射电镜观察胰岛β细胞超微病变,免疫组化法检测胰岛中胰岛素水平。结果(1)与DM组相比,RSG组血清胰岛素水平逐渐上升,血糖水平逐渐下降。(2)RSG组β细胞数量增加,分泌颗粒增多。(3)RSG组胰岛表达胰岛素水平逐渐增高,并明显大于DM组(P<0.05)。结论罗格列酮对糖尿病大鼠残存胰岛β细胞具有一定的保护作用。

Objective To explore the protective effect of rosiglitazone on survival pancreatic beta cells of diabetic rats. Methods The STZ-induced diabetic rats and control rats were grouped into 3 groups： normal control （A, n = 8） and diabetic control （B, n = 20） and rosiglitazone -treated diabetic group （C,n= 20）. Rats with FBG≥ 16.7mmol/L were served as diabetic models. Rosiglitazone sodium（5mg/kg · d^-1 ） were applied. One-, two-, four-, seven-, and ten weeks after rosiglitazone treatment, 4 animals in both group B and C were executed respectively. Pancreas samples were removed for study. Fasting blood samples were collected for the assessment of FBG, insulin（INS） levels. Ultrastructrures of pancreatic islet were observed by transmission electron microscopy. The expression levels of insulin in pancreatic islet were measured by immunohistochemistry. Results Levels of blood insulin in group C were increased over time, and the FBG levels were decreased gradually. The size of pancreatic islet was enlarged and the beta cell mass was raised as well in those animals of group C. The levels of expression for insulin in islets were significantly higher in group C than in group B. Increased secretory granules of beta cells were observed under the transmission electron microscopy in group C. Conclusion Rosiglitazone treatment can protect the survival pancreatic islet beta cells.