构建糖尿病大鼠模型:Klotho基因导入对冠状动脉的保护作用

Construction of diabetic rat models:protective effect of Klotho gene transfer on coronary artery

背景:Klotho基因是一种与机体衰老、代谢以及疾病有重要关联的基因,并已在小鼠动物实验中证实可减缓和抑制动脉粥样硬化,其机制与参与脂类代谢有关。目的:构建糖尿病大鼠模型,观察Klotho基因导入是否对糖尿病大鼠冠状动脉具有保护作用。方法:由正常SD大鼠肾组织提取Klotho基因,对目的基因进行PCR扩增,以腺病毒作为载体。随机将SD大鼠分为模型组、对照组和治疗组,进行糖尿病造模;将Klotho基因导入治疗组,对照组导入普通腺病毒,模型组不作任何处理。造模成功后12周时处死模型动物,检测血清低密度脂蛋白、高密度脂蛋白浓度及冠状动脉内膜、中膜厚度比。结果与结论:高密度脂蛋白浓度,治疗组高于模型组及对照组,治疗组与模型组、治疗组与对照组差异均有显著性意义(P<0.05),模型组与对照组间差异无显著性意义(P>0.05)。低密度脂蛋白浓度,各模型组均有明显升高,但差异无显著性意义(P>0.05)。计算各组内膜厚度,治疗组显著小于模型组及对照组,差异均有显著性意义(P<0.01),而模型组与对照组差异无显著性意义(P>0.05)。各组间中膜厚度差异无显著性意义(P>0.05)。内膜、中膜厚度比,治疗组分别与模型组及对照组相比,差异均有显著性意义(P<0.01);治疗组与正常组差异无显著性意义(P>0.05),表明KL基因导入后内膜、中膜厚度比基本接近于正常水平,低于模型组及对照组,内膜增厚程度减小。提示Klotho基因导入糖尿病大鼠后对冠状动脉具有保护作用。

BACKGROUND： Klotho gene has an important correlation with organism aging, metabolism and disease. It is confirmed by mouse experiments that Klotho gene can slow down and inhibit atherosclerosis, and its underlying mechanism is involved in lipid metabolism.OBJECTIVE： To establish diabetic rat models and observe whether Klotho gene transfer has a protective effect on coronary artery of diabetic rats. METHODS： Klotho gene was extracted from the kidney tissue of normal Sprague-Dawley rats. The target gene was amplified by polymerase chain reaction. Adenovirus was taken as a carrier. Sprague-Dawley rats were randomly divided into model, control and treatment groups to establish diabetic rat models. Klotho gene was transferred into the treatment group, and common adenovirus was transferred into the control group. Rats in model group did not receive any treatment. At the 12 ^th week after modeling, the model animals were sacrificed. Serum low density lipoprotein, high density lipoprotein concentrations, coronary artery intima-media thickness ratio were determined. RESULTS AND CONCLUSION： The high density lipoprotein concentration in treatment group was significantly higher than that in the model and control groups（P〈 0.05）. There was no significant difference in high density lipoprotein concentration between model and control groups. The low density lipoprotein in each group was significantly increased, but the differences were not significant（P 〉0.05）. The intima thickness in treatment groupwas significantly smaller than that in model and control groups（P 〈0.01）, but the differences between model and control groups were not significant（P 〉0.05）. There was no significant difference in media thickness between each group（P 〉0.05）. The intima-media thickness ratio in the treatment group was significantly lower than that in the model and control groups（P 〈0.01）. There was no significant difference in the intima-media thickness ratio between treatment and normal groups（P〉 0.05）. These results showed that after Klotho gene transfer, the intima-media thickness ratio was substantially close to the normal level, and lower than that in the the model and control groups, and the degree of intimal thickening reduced. These results suggest that Klotho gene has a protective effect on coronary artery after being transferred into diabetic rats.