To understand the role of intracellular zinc ion (Zn2+) dysregulation in mediating age-related neurodegenerative changes, particularly neurotoxicity resulting from the generation of excessive neurotoxic amyloid-β (Aβ) peptides, this study aimed to investigate whether N, N, N′, N′-tetrakis (2-pyridylmethyl) ethylenediamine (TPEN), a Zn2+-specific chelator, could attenuate Aβ25–35-induced neurotoxicity and the underlying electrophysiological mechanism. We used the 3-(4, 5-dimethyl-thiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay to measure the viability of hippocampal neurons and performed single-cell confocal imaging to detect the concentration of Zn2+ in these neurons. Furthermore, we used the whole-cell patch-clamp technique to detect the evoked repetitive action potential (APs), the voltage-gated sodium and potassium (K+) channels of primary hippocampal neurons. The analysis showed that TPEN attenuated Aβ25–35-induced neuronal death, reversed the Aβ25–35-induced increase in intracellular Zn2+ concentration and the frequency of APs, inhibited the increase in the maximum current density of voltage-activated sodium channel currents induced by Aβ25–35, relieved the Aβ25–35-induced decrease in the peak amplitude of transient outward K+ currents (IA) and outward-delayed rectifier K+ currents (IDR) at different membrane potentials, and suppressed the steady-state activation and inactivation curves of IA shifted toward the hyperpolarization direction caused by Aβ25–35. These results suggest that Aβ25–35-induced neuronal damage correlated with Zn2+ dysregulation mediated the electrophysiological changes in the voltage-gated sodium and K+ channels. Moreover, Zn2+-specific chelator-TPEN attenuated Aβ25–35-induced neuronal damage by recovering the intracellular Zn2+ concentration.

中文翻译：

---

TPEN 通过改变电压门控钠和钾通道的电生理特性来减轻淀粉样蛋白-β25-35 诱导的神经元损伤

为了了解细胞内锌离子 (Zn2+) 失调在介导与年龄相关的神经退行性变化中的作用，特别是由过量的神经毒性淀粉样蛋白-β (Aβ) 肽的产生引起的神经毒性，本研究旨在调查 N、N、N'、 N'-四 (2-吡啶基甲基) 乙二胺 (TPEN) 是一种 Zn2+ 特异性螯合剂，可以减弱 Aβ25-35 诱导的神经毒性和潜在的电生理机制。我们使用 3-(4, 5-dimethyl-thiazol-2-yl)-2, 5-diphenyltetrazolium bromide 测定法测量海马神经元的活力，并进行单细胞共聚焦成像以检测这些神经元中 Zn2+ 的浓度。此外，我们使用全细胞膜片钳技术来检测诱发重复动作电位（APs），初级海马神经元的电压门控钠和钾 (K+) 通道。分析表明，TPEN 减弱了 Aβ25-35 诱导的神经元死亡，逆转了 Aβ25-35 诱导的细胞内 Zn2+ 浓度和 APs 频率的增加，抑制了 Aβ25 诱导的电压激活钠通道电流的最大电流密度的增加。 –35，缓解了 Aβ25–35 诱导的不同膜电位下瞬时外向 K+ 电流 (IA) 和外向延迟整流器 K+ 电流 (IDR) 峰值幅度的降低，并抑制了 IA 的稳态激活和失活曲线向由 Aβ25-35 引起的超极化方向移动。这些结果表明，与 Zn2+ 失调相关的 Aβ25-35 诱导的神经元损伤介导了电压门控钠和 K+ 通道的电生理变化。此外，Zn2+ 特异性螯合剂-TPEN 通过恢复细胞内 Zn2+ 浓度来减轻 Aβ25-35 诱导的神经元损伤。