【摘要】 目的:比较具有氧化还原活性的过渡金属离子Cu²⁺（Cu）诱导形成的Aβ聚集物（Aβ-Cu复合物）与Aβ自聚集形成的纤丝（Fibrillar Aβ,f Aβ）对小胶质细胞激活作用的差异。方法:制备Aβ-Cu复合物和fAβ,利用小鼠BV-2小胶质细胞株,分别以不同浓度的Aβ-Cu复合物和fAβ于37℃刺激24 h,检测细胞上清液中的TNF-α（Tumor necrosis factor-α）、NO（Nitric oxide）以及H₂O₂（Hydrogen Peroxide）的含量。分别收集Aβ-Cu复合物和f Aβ作用24 h后的大鼠原代小胶质细胞条件培养液,通过观察该条件培养液对大鼠原代海马神经元细胞活力的影响,评价小胶质细胞介导的间接神经元毒性。结果:（1）在不引起直接神经毒性剂量（2.5μM）下,Aβ-Cu复合物激活小胶质细胞释放TNF-α（P<0.01）、NO（P<0.05）以及H₂O₂（P<0.05）的作用强于f Aβ。（2）在此剂量下,Aβ-Cu复合物通过激活小胶质细胞引起的间接神经元毒性强于fAβ（P<0.05）。结论:与fAβ相比,非神经毒性剂量的Aβ-Cu复合物对于小胶质细胞具有更强的激活作用,并由此引发更为明显的神经元毒性。更多还原

【Abstract】 Objective: To compare the effects of Aβ-Cu complex with fibrillar Aβ（f Aβ） on microglial activation. Methods: f Aβwas prepared by dissolving Aβ1-40 in dd H₂O, which was followed by incubation at 37 ℃ for 7 days. Aβ was incubated with Cu²⁺（Cu） at an equimolar ratio to obtain the Aβ-Cu complex. BV-2 microglial cells were treated with Aβ-Cu and f Aβ. The TNF-α and nitric oxide levels in the media were determined and cell viability was measured as well. Extracellular hydrogen peroxide was quantified by fluorometric assay with Amplex Red. The conditioned medium of Aβ-Cuactivated and f Aβ-activated microglia was collected, and the microglia-mediated neurotoxicity was observed. Results: Without causing neuronal cell toxicity, compared with f Aβ, the activation effect of Aβ-Cu complex on microglial cells was stronger, releasing more TNF-α（P<0.01）, nitric oxide（P<0.05） and hydrogen peroxide（P<0.05）. In addition, the conditioned medium of Aβ-Cu complex-treated microglia could cause more obvious neurotoxicity than that of f Aβ（P<0.05）.Conclusions: Compared with f Aβ, Aβ-Cu complex has a stronger effect on microglial activation and microglia-mediated neurotoxicity.更多还原