Beta-淀粉样蛋白对体外培养人神经母细胞瘤细胞的毒性作用

Neurotoxicity of beta-amyloid on neuroblastoma cells in vitro

目的观察Beta-淀粉样蛋白(beta-amyloid,Aβ)对体外培养人神经母细胞瘤细胞(SHSY5Y)的毒性作用。方法将体外培养的人神经母细胞瘤细胞,分为BSA对照组(0.5 mg/m L)、Aβ组(Aβ1-42寡聚体,50μg/m L)和Aβ+p75-FC组(50μg/m L Aβ1-42+100μg/m L p75-FC,p75-FC为p75NTR胞外段与人Ig G FC段的融合蛋白,能够竞争性阻断p75NTR),分别干预72 h,采用结晶紫染色法观测SH-SY5Y细胞轴突的生长长度,采用MTT法检测SH-SY5Y细胞存活率。结果干预结束后,Aβ组SH-SY5Y细胞轴突长度(42.83±14.98)μm明显短于BSA对照组[(69.76±19.24)μm,P=0.003];在同时给予p75-FC干预后,其轴突长度(65.37±17.52)μm与BSA对照组轴突长度比较差异无统计学意义(P=0.600)。Aβ组SH-SY5Y细胞D(490)值(0.203±0.068)明显低于BSA对照组(0.428±0.094,P=0.002);在同时给予p75-FC干预后,其D(490)值(0.447±0.103)与BSA对照组比较差异无统计学意义(P=0.768)。结论 Aβ对人神经母细胞瘤细胞具有毒性作用,且通过p75NTR介导实现。

Objective To determine the effect of beta-amyloid （Aβ） on the viability of neuroblastoma cells in vitro. Methods Neuroblastoma SH-SY5Y cells were divided into BSA group （0.5 mg/mL）, Aβ group （50 μg/mL Aβ1-42） and Aβ＋p75-FC groups （50 μg/mL Aβ1-42＋100 μg/mL p75-FC, fusion protein p75-FC is p75NTR extracellular domain of human IgG FC segment and able to competitively block p75NTR）. All experimental groups were treated for 72 h. Crystal violet staining was performed to examine the axonal growth of the SH-SY5Y cells. MTT assay was conducted to detect the viability of SH-SY5Y cells. Results The axon length in SH-SY5Y cells was significantly shorter in the Aβ group than the BSA group （42.83±14.98 vs 69.76±19.24 μm, P=0.003）, but there was no difference observed when co-cultured with p75-FC （axon length： 65.37±17.52 μm, P=0.600, compared with BSA group）. MTT assay indicated that the cell viability was lower in the Aβ group than the BSA group （0.203±0.068 vs 0.428±0.094, P=0.002）, but there was no difference observed when co-cultured with p75-FC （0.447±0.103, P=0.768, compared with BSA group）. Conclusion Aβ exerts a toxic effect on SH-SY5Y cells, which might be mediated by p75NTR.