小檗碱对链脲菌素和高糖高脂饲料诱导糖尿病大鼠骨骼肌CDK9和cyclin T1表达的影响

目的观察小檗碱对2型糖尿病大鼠骨骼肌病理结构改变及CDK9和cyclin T1蛋白表达的影响。方法腹腔注射链脲菌素(35 mg·kg~(-1))加高糖高脂饲料喂养16 wk建立2型糖尿病大鼠模型,随后16 wk每天分别拌食给予低中高剂量小檗碱(75、150、300 mg·kg~(-1))、非诺贝特(100 mg·kg~(-1))和罗格列酮(4 mg·kg~(-1)),用HE染色检查骨骼肌结构病变和免疫组化检测CDK9和cyclin T1的表达。结果骨骼肌纤维在各组大鼠中仍正常分布,中高剂量小檗碱部分地改善糖尿病肌纤维的萎缩;中高剂量小檗碱和罗格列酮都能明显恢复糖尿病大鼠骨骼肌中表达降低的CDK9和cyclin T1至正常水平(P<0.01)。结论小檗碱调控骨骼肌CDK9和cyclin T1蛋白的表达可能是其改善糖尿病骨骼肌纤维萎缩的机制之一。

Effect of berberine on CDK9 and cyclin T1 expression in skeletal muscle of diabeticrats induced by streptozotocin and a high-carbohydrate/high-fat diet

AIM To investigate the effect of berberine on damaged skeletal muscle and on the cyclin-dependent kinase 9(CDK9)and cyclin T1 expression in type 2 diabetic rats.METHODS Type 2 diabetes mellitus rats were in duced by an injection of 35 mg·kg-1 streptozotocin and a high-carbohydrate/high-fat diet for 16 wk.From wk 17 to wk 32，diabetic rats were given low-，middle-，high-dose berberine(75，150，300 mg·kg-1)，fenofibrate(100 mg·kg-1) and rosiglitazone(4 mg·kg-1)by oral administration，respectively.The skeletal muscle structure was observed with hematoxylin-eosin(HE)staining and the CDK9 and cyclin T1 expression Were detected by immunohistochemistry.RESULTS Fibre distribution remained normal in skeletal muscles of all the groups.Middle-，high-dose berberine partly im proved diabetic fibre atrophy.Middle-，high-dose berberine and rosiglitazone significantly increased the expressions for both of CDK9 and cyclin T1(P＜0.01＝.CONCLUSION Berberine modulates the CDK9 and cyclin T1 expressions in diabetic skeletal muscle and ameliorates the fibre damage.