原花青素对糖尿病大鼠胰腺铁代谢紊乱保护作用

Protective effect of proanthocyanidin on pancreatic iron metabolism disorder in diabetic rats

目的探讨葡萄籽原花青素对糖尿病大鼠胰腺铁代谢紊乱的保护作用及机制。方法将健康雄性SD大鼠随机分为对照组(10只)和糖尿病组(30只),再将糖尿病大鼠随机分为3组,分别为模型组、原花青素低、高剂量组,测定各组大鼠血糖及胰岛素水平,采用试剂盒法测定大鼠胰腺组织转铁蛋白(TF)、转铁蛋白受体(TFR)及铁含量,测定超氧化物歧化酶(SOD)、还原型谷胱甘肽(GSH)、丙二醛(MDA)和谷胱甘肽过氧化物酶(GSH-Px)水平。结果与对照组比较,模型组大鼠血糖水平上升,胰岛素水平下降,转铁蛋白、转铁蛋白受体及铁含量上升,SOD、GSH、GSH-Px活力下降,MDA水平上升,差异均具有统计学意义(P <0.05)。与模型组比较,原花青素组大鼠胰岛素水平升高,转铁蛋白、转铁蛋白受体及铁含量下降,SOD、GSH、GSH-Px活力升高(P <0.05)。相关分析结果显示,TF、TFR、铁含量与血糖和胰岛素抵抗指数(HOMA-IR)呈正相关(P <0.05)。结论原花青素对糖尿病大鼠胰腺具有一定保护作用,其机制可能与调节铁代谢紊乱,减轻氧化损伤有关。

Objective To investigate protective effect of grape seed proanthocyanidin extract(GSPE) on pancreatic iron metabolism disorder and its mechanism in diabetic rats. Methods Healthy male Sprague-Dawley(SD) rats were randomly divided into a control group(n = 10) and diabetes group(30 rats with two intraperitoneal injections of 30 mg/kg streptozotocin);then the rats of diabetes group were further randomly assigned to a model group, a low and a high GSPE groups(by intragastric administration at dosages of 100 and 250 mg/kg once a day continuously for two weeks). By the end of the treatments, all rats′ blood samples were collected for determinations of glucose and insulin level;the specimens of the rats′ pancreatic tissues were also sampled for detections of transferrin(TF)/TF receptor(TFR)/iron, superoxide dismutase(SOD), reduced glutathione(GSH), malondialdehyde(MDA), and glutathione peroxidase(GSH-Px) with kit method.Results Significantly increases in blood glucose, pancreatic tissues′ TF, TFR, iron, MDA and decreases in blood insulin,pancreatic tissues′ SOD, GSH, GSH-PX activity were detected in the model rats compared to those in the control rats(P <0.05 for all). The rats of GSPE dose groups had significantly higher blood insulin, pancreatic tissues′ SOD, GSH, GSH-PX activity but lower pancreatic tissues′ TF, TFR, iron in comparison to the model rats(all P < 0.05). Correlation analysis revealed that the pancreatic tissues′ TF, TFR, iron were positively associated with blood glucose and homeostatic model assessment for insulin resistance(HOMA-IR) in the rats. Conclusion Proanthocyanidin has a protective effect on pancreas and the effect may be related to the regulation of iron metabolism disorder and reduction of oxidative damage in diabetic rats.