决明子对高同型半胱氨酸血症兔动脉粥样斑块干预的分子机制研究

Molecular mechanism study of intervention effect of Cassia seed on atherosclerotic plaque of rabbits with hyperhomocysteinemia

目的：探讨决明子对高同型半胱氨酸（ HHcy）血症兔动脉粥样斑块干预的分子机制。方法将40只家兔随机分成对照组、蛋氨酸组、决明子﹢蛋氨酸组、立普妥﹢蛋氨酸组。采用高L-蛋氨酸建立兔高同型半胱氨酸血症模型。比较各组兔血浆同型半胱氨酸（ Hcy）含量，应用血管超声检查斑块形成过程，免疫组化观察Bcl-2、Bax在斑块中的表达水平，分析决明子对病理过程的干预效果。结果决明子组、立普妥组与蛋氨酸组比较，腹主动脉内-中膜厚度（IMT）显著减少，血流峰值（Vp）显著减慢，差异有统计学意义（P﹤0.05），决明子组、立普妥组两组比较差异无统计学意义（ P﹥0.05）。免疫组化显示，蛋氨酸组Bax表达与对照组比较差异有统计学意义（ P﹤0.01）。决明子组和立普妥组与蛋氨酸组比较，平滑肌细胞、泡沫细胞的Bax的阳性表达率下调，Bcl-2的表达水平轻度上调，差异有统计学意义（P﹤0.01）。决明子组Bax/Bcl-2比值降低。结论决明子可通过下调Bax/Bcl-2比值，干预高同型半胱氨酸血症兔动脉粥样硬化斑块的形成。

Objective To investigate the molecular mechanism of intervention effect of Cassia seed on atherosclerotic plaque of rabbits with hyperhomocysteinemia. Methods Forty rabbits were randomly divided into four groups：control group, methionine group,Cassia seed ﹢ methionine group,Lipitor﹢methionine group. Rabbits with hyperhomocysteinemia model were established using high L-methionine. The plasma levels of homocysteine（ Hcy）in rabbits were compared among the four groups. The formation process of plaque was detected by vascular ultrasound,the expression levels of Bcl-2 and Bax were observed by immunohistochemistry,and the intervention effect of Cassia seed on the pathologic process of the disease was analyzed. Results Compared with methionine group,IMT of abdominal aorta and Vp of abdominal aorta decreased obviously in Cassia seed group and Lipitor group, there were significant differences（ P ﹤0. 05 ）,but there were no significant differences between Cassia seed group and Lipitor group（ P ﹥0. 05 ）. Immunohistochemistry showed that,there was significant difference in the Bax expression level between methionine group and control group（ P﹤0. 01 ）. Compared with methionine group,the positive expression rate of Bax in smooth muscle cells and foam cells decreased,the expression levels of Bcl-2 increased slightly in Cassia seed group and Lipitor group,there were significant differences（P﹤0. 01）. The ratio of Bax/Bcl-2 decreased in Cassia seed group. Conclu-sions Cassia seed can intervene the formation of atherosclerotic plaque of rabbits with hyperhomocysteinemia through down-regulation the ratio of Bax/Bcl-2 .