淀粉样蛋白膜内片段的AD相关生物学特性研究

Research on the Biological Characteristics of Intramembranous Fragments of Amyloid-β Related with AD

目的:体外条件下研究淀粉样蛋白膜内片段(intramembranous fragments of amyloid-β,IF-Aβ)对Aβ42成纤维和神经毒性的影响。方法:(1)硫磺素T法检测IF-Aβ对Aβ42成纤维性的影响;(2)MTT法和荧光分光光度计检测IF-Aβ对经过Aβ42预处理的体外培养神经元的活性和胞浆钙离子浓度影响。结果:(1)IF-Aβ本身无成纤维性,而且可以抑制或解聚Aβ42成纤维;(2)相对于单独经Aβ42预处理的体外培养神经元,IF-Aβ的加入可以提高神经元的活性和降低胞浆钙离子的浓度。结论:IF-Aβ具有保护体外培养神经元免受Aβ42毒性作用的功能,为阿尔茨海默病(Alzheimer's disease,AD)的在体治疗研究奠定了基础。

Objective： To study the effect of intramembranous fragments of amyloid- （IF-A） on fibroplastic and neurotoxic activities of AI342 in vitro. Methods： Thioflavin T was applied to detect IF-A effect on A1342 assembly. The biological activity of the IF-A was assessed by the CellTiter 96 Cell Proliferation Assay （MTT assay）. The calcium ion concentration in cell were also detected, as well as the mixtures ofA1342： IF-A. Results： （1） IF-A showed no aggregation at concentrations up to 750 p,M but substantial inhibition to AI342 fibril growth; （2）Compared with the in vitro cultured neuron which were treated only by AI342, that treated by IF-AI3 and A1342 （at a 1：1 concentration ratio） showed an increased activities and a decreased calcium ion concentration. Conclusion： IF-A could protect neuron viability from toxic damage by AI342 in vitro. It provides a foundation for the clinical treatment of Alzheimer＇s disease/n v/vo.