糖尿病大鼠钙化血管中Msx2和Wnt3a的表达

Upregulation of Msx2 and Wnt3a in Calcified Artery of Diabetic Rat

目的研究糖尿病对血管钙化的影响及Msx2和Wnt3a基因在钙化血管中的表达变化。方法将48只雄性Wistar大鼠随机分为四组:维生素D3和尼古丁诱导的单纯血管钙化组(n=12)、链脲佐菌素诱导的单纯糖尿病组(n=12)、链脲佐菌素联合维生素D3和尼古丁诱导的糖尿病合并血管钙化组(n=12)和正常雄性Wistar大鼠为正常对照组(n=12)。测定大鼠血糖、血清胰岛素、总胆固醇和甘油三酯水平,以血管von Kossa染色、血管钙含量和碱性磷酸酶活性作为判断血管钙化程度的指标,测定大鼠血管中Msx2和Wnt3a mRNA的表达。结果与正常对照组相比,单纯血管钙化组大鼠血管中Msx2和Wnt3a mRNA相对表达量有所升高(P<0.05),但血管钙含量和碱性磷酸酶活性无明显变化。与正常对照组及单纯血管钙化组相比,糖尿病合并血管钙化组大鼠的血管中,可见沿中膜弹力层内广泛分布的钙盐沉积,大鼠血管中钙含量和碱性磷酸酶活性以及血管内Msx2和Wnt3amRNA相对表达量明显增高(P<0.05)。结论糖尿病可以明显加速血管钙化的发生和发展。在糖尿病大鼠钙化血管中,骨形成过程中的转录因子Msx2和Wnt3a表达增高,提示血管钙化是一个类似于骨形成的过程,Msx2和Wnt3a参与血管钙化病变的发生。

Aim To investigate the effect of diabetes on rat vascular calcification,and the expression of Msx2 and Wnt3a mRNA in calcified artery of diabetic rat.Methods 48 male Wistar rats were randomly divided into 4 groups：vitamin D3 and nicotine（VDN）group（n=12）undergoing vitamin D3 and nicotine treatment,and diabetes mellitus（DM）group（n=12）undergoing injection of streptozotocin（STZ）to induce diabetes,and diabetes mellitus vitamin D3 and nicotine（DM＋VDN）group（n=12）undergoing injection of STZ and vitamin D3 and nicotine treatment.Another 12 rats were used as normal controls（CON group,n=12）.Measurements of metabolic parameters（glucose,insulin,total cholesterol and triglyceride）were performed.von Kossa calcium stain,aortic calcium content and alkaline phosphatase（ALP）activity were used as indicators to determine the extent of vascular calcification.Real-time PCR was performed to detect the expression of Msx2 and Wnt3a mRNA.Results Compared with CON group,four weeks of vitamin D3 and nicotine treatment alone increased the expression of Msx2 and Wnt3a mRNA in aorta slightly（P〈0.05）,but there were no significant differences in aortic calcium content or ALP activity.In the DM＋VDN group,calcium deposition in aorta,aortic calcium content,ALP activity and expression of Msx2 and Wnt3a mRNA in artery increased significantly compared with CON group and VDN group（P〈0.05）.Conclusion Diabetes may accelerate vascular calcification.Bone-associated transcript factors,Msx2 and Wnt3a are up-regulated in calcified artery of diabetic rat.It suggests that vascular calcification is a process similar to bone formation,and Msx2 and Wnt3a may involve in the occurrence of vascular calcification.