芦荟大黄素对Al^(3+)存在下Aβ_(42)聚集和细胞增殖抑制作用的影响  

Effect of Aloe-emodin on Aβ_(42) Aggregation and Cytotoxicity in Presence of Al^(3+)

作　　者：姚妮 王楚茵 赵希彤 陈杨[1] 张谦[1] 方芳[1] 关君[1] YAO Ni;WANG Chuyin;ZHAO Xitong;CHEN Yang;ZHANG Qian;FANG Fang;GUAN Jun(School of Chinese Materia Medica,Beijing University of Chinese Medicine,Beijing 102488,China)

机构地区：[1]北京中医药大学中药学院,北京102488

出　　处：《中国实验方剂学杂志》2022年第18期99-107,共9页Chinese Journal of Experimental Traditional Medical Formulae

基　　金：国家自然科学基金面上项目(82074001);北京中医药大学科研发展基金项目(2020072120050)。

摘　　要：目的在体外研究芦荟大黄素(AE)对金属铝离子(Al^(3+))诱导的β-淀粉样蛋白_(42)(Aβ_(42))聚集的抑制作用,以及对已形成的Aβ_(42)-Al^(3+)聚集体的解聚作用,并考察其对Al^(3+)存在下Aβ_(42)聚集产生的细胞增殖抑制作用的影响。方法设置Aβ_(42)组、Aβ_(42)+Al^(3+)组、Aβ_(42)+AE组、Aβ_(42)+Al^(3+)+AE组,以及解聚作用考察实验,应用硫黄素T(ThT)荧光试验、透射电子显微镜(TEM)、动态光散射法(DLS)及噻唑蓝(MTT)细胞增殖抑制作用试验分别检测各组Aβ_(42)的聚集纤维化过程、聚集体形貌、聚集体尺寸及细胞增殖抑制作用。结果与Aβ_(42)组比较,Al^(3+)可促进Aβ_(42)聚集,使ThT荧光强度升高至124.48%,诱导Aβ_(42)聚集形成粒径较大的纤维束,并显著降低人神经母细胞瘤细胞SH-SY5Y的细胞活力(P<0.01),使细胞生存率降低至51.05%。AE不仅能抑制Aβ_(42)聚集,而且可浓度依赖性地抑制Al^(3+)诱导的Aβ_(42)聚集;与Aβ_(42)+Al^(3+)组比较,高浓度AE使ThT荧光强度降低至41.66%,改变多肽聚集途径形成粒径较小的无定型结构聚集体,并显著抑制Al^(3+)诱导Aβ_(42)产生的细胞增殖抑制作用(P<0.01),使细胞生存率恢复至84.87%。解聚研究发现,AE可解聚Aβ_(42)-Al^(3+)聚集体,使已形成的聚集体消失,形成一些毒性较低的小粒径短纤维及无定型结构聚集体。结论AE可抑制Al^(3+)存在下的Aβ_(42)聚集及细胞增殖抑制作用,解聚已形成的Aβ_(42)-Al^(3+)聚集体,缓解其产生的细胞增殖抑制作用,为探索AE治疗阿尔茨海默病的作用机制奠定基础。Objective To study the inhibitory effect of aloe-emodin(AE)on aluminum ion(Al^(3+))-inducedβ-amyloid protein _(42)(Aβ_(42))aggregation and its depolymerization on formed Aβ_(42)-Al^(3+)aggregates in vitro,and to investigate the effect of AE on the cytotoxicity of Aβ_(42) aggregation in the presence of Al^(3+).Method The Aβ_(42) group,Aβ_(42)+Al^(3+)group,Aβ_(42)+AE group,Aβ_(42)+Al^(3+)+AE group and the depolymerization test group were set up in the experiment.The aggregation fibrosis process,aggregation morphology,aggregation size and cytotoxicity of Aβ_(42) in each group were detected by thioflavin T(ThT)fluorescence assay,transmission electron microscopy(TEM),dynamic light scattering(DLS)experiment and thiazolyl blue(MTT)cytotoxicity assay.Result Compared with the Aβ_(42) group,Al^(3+)could promote Aβ_(42) aggregation,increase the fluorescence intensity of ThT by 124.48%,induce the aggregation of Aβ_(42) to form fiber bundles with larger particle size,and significantly reduce the cell viability of human neuroblastoma SH-SY5Y cells(P<0.01),thus reducing the cell survival rate to 51.05%.AE not only inhibited Aβ_(42) aggregation,but also inhibited Al^(3+)-induced Aβ_(42) aggregation in a concentration-dependent manner.Compared with the Aβ_(42)+Al^(3+)group,high concentration of AE could reduce the ThT fluorescence intensity to 41.66%,and change the polypeptide aggregation pathway to form amorphous aggregates with small particle size.Besides,it significantly inhibited the cytotoxicity of Aβ_(42) induced by Al^(3+)(P<0.01),and restored the cell survival rate to 84.87%.Further depolymerization was conducted,AE could depolymerize Aβ_(42)-Al^(3+)aggregates to make the formed aggregates disappear and form some small-particle short fibers and amorphous structure aggregates with low toxicity.Conclusion AE can inhibit Aβ_(42) aggregation and cytotoxicity in the presence of Al^(3+),depolymerize the formed Aβ_(42)-Al^(3+)aggregates and alleviate the cytotoxicity,thus laying the foundation for exploring th

关 键 词：阿尔茨海默病 Β-淀粉样蛋白 芦荟大黄素 聚集抑制剂 铝离子(Al^(3+)) 螯合作用 细胞增殖抑制作用 

分 类 号：R22[医药卫生—中医基础理论] R28[医药卫生—中医学] R96[理学—分析化学] O657.34[理学—化学]