锌/番茄红素对糖尿病小鼠心肌的保护作用

THE PROTECTIVE EFFECTS OF ZINC AND LYCOPENE ON MYOCARDIUM IN MICE WITH DIABETES MELLITUS

目的探究锌/番茄红素对链脲佐菌素(STZ)诱导糖尿病心肌病小鼠的保护作用。方法 60只健康成年小鼠随机分为空白对照、空白对照+锌、空白对照+锌+番茄红素、模型、模型+锌和模型+锌+番茄红素组,共6组。模型组小鼠腹腔注射STZ,连续5 d,空白对照组小鼠腹腔注射等体积柠檬酸缓冲液,实验连续3月。每周检测小鼠体质量,每2 w检测小鼠血糖。实验结束后,取动物心肌组织,光镜下观察心肌组织,实时免疫荧光定量PCR检测组织中丝氨酸/苏氨酸蛋白激酶(Akt2)、金属硫蛋白(MT)、葡萄糖转运体4(GLUT4)的表达变化。结果与空白对照组比较,模型组小鼠出现明显多饮、多食、多尿及体质量下降(三多一少),血糖明显增高(P<0.05),小鼠心肌中Akt2、MT表达下调,GLUT4表达上调(P<0.05)。给予补锌+番茄红素后,小鼠表现的"三多一少"症状缓解,血糖明显下降(P<0.01)。小鼠心肌组织中Akt2、GLUT4表达上调(P<0.05),MT表达没有明显改变(P>0.05)。结论锌/番茄红素对实验性糖尿病小鼠心肌具有一定的保护作用。

Objective To explore the protective effects of lycopene and zinc against diabetic cardiomyopathy induced by streptozotocin （STZ） in mice. Methods Sixty healthy adult mice were randomly divided into six groups： control, control＋zinc, control＋zinc＋ lycopene, model, model ＋ zinc, and model ＋ zinc ＋ lycopene. The model group was injected intraperitoneally with STZ for five consecutive days, and the control group was injected intraperitoneally with the same volume of citric acid buffer. The experiment lasted for 3 months. We monitored the changes of body weight every week and blood sugar every 2 weeks. After the experiment, the myocardial tissue was extracted and observed under light microscope, and the serine/threonine protein kinase （Akt2）, metallothionein （MT） and glucose transporter 4 （GLUT4） expressions were detected by real-time fluorescent quantitative PCR in myocardial tissue. Results Compared with the control group, diabetic mice had obvious polydipsia, polyphagia, polyuria, weight loss, and also higher blood sugar level （P〈0.05）. The expression levels of Akt2 and MT in myocardial tissue decreased, while the GLUT4 increased （P〈0.05）. In model ＋ zinc ＋ lycopene group, the symptoms of diabetes alleviated and blood sugar level went down significantly compared with that in control group （P〈0.01） . The expression levels of Akt2 and GLUT4 in myocardial tissue increased （P〈0.05） , but MT expression was not significantly changed. Conclusion Zinc and lycopene have some protective effects on the myocardium in experimental diabetic mice.