人参皂苷Rg2抗MTD大鼠海马神经元凋亡的研究(英文)

Ginsenoside Rg2 attenuates learning and memory loss through an anti-apoptotic property in a rat model of multi-infarct dementia

目的:观察多发梗塞性痴呆模型大鼠CPU凋亡相关蛋白的改变,研究其在学习记忆障碍中的作用机制,并探讨人参皂苷Rg2的干预作用。方法:将复合血栓诱导剂经大鼠左颈总-颈内动脉注射入其左侧大脑半球,诱导半球内血栓形成,造成多发梗塞,从而建立大鼠的学习和记忆功能障碍模型。分别给予不同剂量的人参皂苷Rg2治疗7天,并以尼莫地平进行对照。用Y型电迷宫检测正常对照及痴呆模型大鼠学习和记忆能力的改变;对大鼠的脑组织切片作尼氏染色行病理学检查;以免疫组化方法检测Glu、CalpainⅡ、Caspase-3、Bax的表达。结果:颈内动脉注射复合血栓诱导剂可造成大鼠在Y型电迷宫中的学习和记忆成绩明显降低,与假手术对照组比较有显著差异(P<0.05)。尼氏染色可在大鼠脑片的CPU区发现胶质瘢痕化的微梗塞灶。在免疫组化结果中,Glu、CalpainⅡ、Caspase-3、Bax表达均增高。结论:单侧大脑注射复合血栓诱导剂可造成大鼠的学习记忆能力降低,可部分模拟MID的行为和病理学改变。人参皂苷Rg2能明显改善MID模型大鼠的学习记忆成绩,其作用机制可能与它的钙通道阻滞作用使凋亡蛋白CalpainⅡ、Caspase-3、Bax表达降低有关。

Objective： We evaluated the neurorestorative effects of Ginsenoside Rg2, one of the main bioactive components of Panax ginseng, in a rat model of multi-infarct dementia （MID）. Methods： A MID rat model was established as produced by multiple cerebral infarctions induced by means of a thrombo-inducer. Y-maze learning performance was assessed after thrombo-induction. Results： Immunocytochemieal techniques were employed to assess cell apoptosis as measured by protein expressions of glutamate, calpain Ⅱ, easpase-3 and bax. Leaming and memory performance were impaired by thrombo-inductor induced MID and the expression of glutamate, calpain Ⅱ, caspase-3 and bax were increased in this MID rat model. After ginsenoside Rg2 （2.5, 5 or 10 mg/kg） or nimodipine （50μg/kg） treatment, learning and memory performance was increased and the expression of glutamate, catpain Ⅱ, caspase-3 and bax were decreased in this MID model. Conclusion： These findings suggest that ginsenoside Rg2 improved learning and memory through mechanisms related to anti-apoptosis in MID rats. These results also indicate that Ginsenoside Rg2 may represent a potential neurorestorative treatment strategy for vascular dementia or other ischemic insults.