Institute of Biomedical Engineering, Bogazici University, Istanbul, Turkey.
Curr Alzheimer Res. 2020;17(13):1208-1213. doi: 10.2174/1567205018666210212155750.
Accumulation of toxic strands of amyloid beta (AB), which cause neurofibrillary tangles and, ultimately, cell death, is suspected to be the main culprit behind clinical symptoms of Alzheimer's disease. Although the mechanism of cell death due to AB accumulation is well known, the intermediate phase between the start of accumulation and cell death is less known and investigated, partially due to technical challenges in identifying partially affected cells.
First, we aimed to establish an in vitro model that would show resilience against AB toxicity. Then we used morphological, molecular and electrophysiological assays to investigate how the characteristics of the surviving cells changed after AB toxicity.
To investigate this phase, we used differentiation of SH-SY5Y neuroblastoma stem cells by Retinoic Acid (RA) and Brain Derived Neurotrophic Factor (BDNF) to establish an in vitro model which would be able to demonstrate various levels of resistance to AB toxicity. We utilized fluorescent microscopy and whole cell patch clamp recordings to investigate behavior of the model.
We observed significantly higher morphological resilience against AB toxicity in cells which were differentiated by both Retinoic Acid and Brain Derived Neurotrophic Factor compared to Retinoic Acid only. However, the electrophysiological properties of the Retinoic Acid + Brain-Derived Neurotrophic Factor differentiated cells were significantly altered after AB treatment.
We established a transient survival model for AB toxicity and observed the effects of AB on transmembrane currents of differentiated neurons.
淀粉样β（AB）的毒性链的积累被怀疑是阿尔茨海默病临床症状背后的主要罪魁祸首，这些毒性链会导致神经原纤维缠结，并最终导致细胞死亡。虽然由于 AB 积累导致细胞死亡的机制是众所周知的，但从积累开始到细胞死亡的中间阶段知之甚少，部分原因是识别部分受影响细胞的技术挑战。
首先，我们旨在建立一种对 AB 毒性具有抗性的体外模型。然后，我们使用形态学、分子和电生理测定来研究 AB 毒性后存活细胞的特征如何变化。
为了研究这一阶段，我们使用维甲酸（RA）和脑源性神经营养因子（BDNF）将 SH-SY5Y 神经母细胞瘤干细胞分化，建立一个能够显示对 AB 毒性不同程度抗性的体外模型。我们利用荧光显微镜和全细胞膜片钳记录来研究模型的行为。
与仅用 RA 分化的细胞相比，用 RA 和脑源性神经营养因子共同分化的细胞对 AB 毒性具有明显更高的形态学抗性。然而，AB 处理后，RA+脑源性神经营养因子分化细胞的跨膜电流的电生理特性发生了显著改变。
我们建立了一个 AB 毒性的短暂存活模型，并观察了 AB 对分化神经元跨膜电流的影响。
