灵芝多糖对2型糖尿病大鼠心肌AGEs及其受体表达的影响

Effect of Ganoderma lucidum polysaccharides on expression of AGEs and AGER in myocardium of T2DM rats

目的:观察灵芝多糖(GLPs)对2型糖尿病大鼠心肌组织中晚期糖基化终产物(advanced glycation end products,AGEs)及其受体(receptor for advanced glycation end products,RAGE)表达的影响,探讨其防治糖尿病大鼠心肌病变的作用机制。方法:采用高能量饮食加小剂量腹腔注射链脲佐菌素(STZ)的方法建立2型糖尿病大鼠模型(Type 2 Diabetes Mellitus,T2DM),成模后将大鼠随机分成6组:正常对照组、模型对照组、灵芝多糖低、中、高剂量治疗组、小檗碱对照组。灌胃治疗12周后测定各组大鼠空腹血糖、血浆胰岛素,免疫组化和蛋白印迹法检测心肌组织中AGEs、RAGE含量的表达。结果:与DM组比较,灵芝多糖组、小檗碱组能有效降低血糖、升高血浆胰岛素水平,降低心肌组织中AGEs、RAGE的表达,其中灵芝多糖高剂量组效果优于小檗碱组。结论:灵芝多糖可显著改善糖尿病大鼠血糖、空腹血浆胰岛素水平,并可能通过抑制心肌组织中AGEs、RAGE的表达实现其保护糖尿病大鼠心肌的作用。

Objective： To investigate the possible mechanism of Ganoderma lucidum polysaccharides（GLPs） in preventing and curing diabetes mellitus（DM） rats myocardial lesions,by analyzing the effects of GLPs on the expression of advanced glycation end products（AGEs） and receptor for advanced glycation end products（RAGE） in myocardium of Type 2 Diabetes Mellitus（T2DM） rats.Methods： Type 2 diabetes model was established by high-energy diet,lower dose of STZ treated SD rat.Rats were divided into six groups randomly once the T2DM model were set successfully.The groups were normal group（NG）,diabetes mellitus group（DMG）,GPLs low dosage group（GLPs-LG）,GPLs middle dosage group（GLPs-MG）,GLPs high dosage group（GLPs-HG） and Berberine group（BerG） respectively.The fasting blood suger（FBS） and fasting serum insulin（FSI） were measured after being orally administrated drugs for 12 weeks,and the content of AGEs,RAGE were detected by immunohistochemistry and western blot.Results： In GLPs-M,GLPs-H and Ber groups,the expression of AGEs,RAGE and the level of FBS were effectively decreased when compared with DM group（P〈0.01）.And the level of secretion of insulin was promoted as well（P〈0.01）.The effect of GLPs-H group is better than GLPs-M group and Ber group（P 〈0.05 or P 〈0.01）.Conclusion： GLPs can significantly improve the level of FBS and FSI,which would contribute to protect myocardium by inhabiting the expression of AGEs,RAGE in DM rats.