葛根总黄酮对载脂蛋白E基因缺陷小鼠动脉粥样硬化病变内细胞凋亡及凋亡相关基因的影响

目的 探讨葛根总黄酮对载脂蛋白E基因缺陷（apoE-／-）小鼠主动脉窦动脉粥样硬化斑块抑制作用的分子机制。方法 采用电镜观察、缺口末端标记（TUNEL）法检测apoE-／-小鼠动脉粥样硬化斑块内的细胞凋亡。免疫组化方法检测平滑肌细胞、巨噬细胞及Caspase一3蛋白的表达。结果 电镜观察到凋亡细胞核形不规则,胞核内染色质浓集、边聚,附着在核膜周边,线粒体肿胀,内质网扩张,超微结构形态符合巨噬细胞早期凋亡,并可见典型凋亡小体形成。TUNEL结果表明,凋亡细胞主要分布在粥样斑块脂质核心处,模型组动脉粥样硬化斑块内凋亡细胞数较多,而葛根总黄酮干预组凋亡细胞数明显减少,葛根高、低剂量组细胞凋亡率明显低于模型组分别为（0．38±0．17）ok,（1．95±1．02）％,（10．50±5．89）％,P〈0．01],葛根高剂量组细胞凋亡率明显低于葛根低剂量组。抗CD68抗体免疫组化染色证实在动脉粥样硬化斑块脂质坏死核心内细胞CD68强阳性表达。葛根高、低剂量治疗组Caspase-3蛋白免疫表达低于模型组,葛根高剂量治疗组低于葛根低剂量治疗组。结论 葛根总黄酮可能通过下调apoE-／-小鼠主动脉窦动脉粥样硬化病变内Caspases-3蛋白的表达,显著降低了动脉粥样硬化病变内巨噬细胞凋亡,从而抑制了动脉粥样硬化斑块的进展。

Effects of the total flavone of radix puerariae on apoptotic cell and apoptotic related-gene in atherosclerotic plaques of apoE gene deficiency mice

OBJECTIVE: To investigate the antiatherosclerosis effect and related mechanisms of total flavone of radix puerariae (TFRP) on atherosclerotic plaques in apoE gene deficiency (apoE-/-) mice. METHODS: apoE-/- mice were treated with saline, TFRP 15 mg . kg(-1). d(-1) or TFRP 85 mg . kg-1. d-1 (n = 8 each group) respectively per gavage for 12 weeks. The apoptotic cells in atherosclerotic plaques were then detected by TUNEL analysis, transmission electron microscope (TEM). The expression of CD-68, SMA and Caspase-3 were determined by immunochemical methods. RESULTS: Early macrophagocyte apoptosis signs were observed under TEM, TUNEL-positive and CD-68 positive cells were found in lipid cores of atherosclerotic plaques. TFRP significantly reduced the number of apoptotic cells in a dose-dependent manner (0.38 +/- 0.17)%, (1.95 +/- 1.02)%, (10.50 +/- 5.89)%, respectively, P < 0.01] in atherosclerotic plaques. TFRP treatment also significantly reduced the immune expression of Caspase-3 protein in a dose-dependent manner. CONCLUSION: TFRP significantly attenuated the development of advanced atherosclerotic plaques in a dose-dependent manner which might related to down-regulated expression of Caspase-3 protein and reduced macrophagocyte apoptotic cells in atherosclerotic plaques post TFRP treatment.