目的研究海参磷脂型二十碳五烯酸(eicosapentaeno-ic acid phosphatidylcholine,EPA-PC)对链脲佐菌素(streptozo-cin,STZ)诱导的糖尿病大鼠血葡萄糖耐量的影响。方法两次腹腔注射STZ建立糖尿病大鼠模型,经不同剂量的海参EPA-PC(25和75 mg.kg-1,以EPA含量计)灌胃60 d。实验结束后,分别检测大鼠空腹血糖(fasting blood-glucose,FBG)、口服葡萄糖耐量(oral glucose tolerance test,OGTT)、糖化血红蛋白(glycated hemoglobin,HbAlc)、糖化血清蛋白(glycated serum protein,GSP)、空腹血清胰岛素(fasting insu-lin,FIN)含量,并分别采用光镜和电镜观察胰腺组织的显微结构和胰岛β细胞的亚显微结构。结果海参EPA-PC可明显改善糖尿病大鼠OGTT(P〈0.05),降低HbAlc和GSP的含量(P〈0.01),促进FIN的分泌(P〈0.01);明显改善胰腺组织的显微结构,修复受损胰岛β细胞的亚显微结构。结论海参EPA-PC对糖尿病大鼠具有明显改善血葡萄糖耐量的作用,其与恢复糖尿病大鼠受损的胰岛外周组织以及胰岛β细胞有关。
Aim To study the hypoglycemic effects of eicosapentaenoic acid rich in phosphatidylcholine(EPA-PC) on diabetes mellitus induced by streptozocin(STZ).Methods Diabetes mellitus model induced twice by STZ,and EPA-PC(25 and 75 mg.kg-1 bw) were given for 60 days.At the end of the experiment,the levels of fasting blood-glucose(FPG),oral glucose tolerance(OGTT),glycated hemoglobin(HbAlc),glycated serum protein(GSP),and fasting insulin(FIN) were assayed by spectrophorometry.The tails of pancreas were excised by light microscope and transmission electron microscope(TEM) to observe its histopathology and ultrastructure.Results EPA-PC had marked functions on ameliorating oral glucose tolerance(P 0.05),decreasing the contents of glycosylated hemoglobin and glycosylated serum protein(P 0.01),and promoting the secretion of fasting insulin(P 0.01).Besides,the damaged pancreatic islets were obviously recovered and the ultrastructural damage of β-cell was clearly restored.Conclusions EPA-PC can effectively regulate and control the glycometabolism in diabetes mellitus.It may relate to recoving the damaged pancreatic islets and β cells,promoting the secretion of insulin.