TPEN attenuates amyloid-β25–35-induced neuronal damage with changes in the electrophysiological properties of voltage-gated sodium and potassium channels

Molecular Brain

Tao Zhang¹  Hong-gang Wang¹  Di An¹  Wen-bo Chen¹  Dan Sun¹  Wan-ge Lu¹  Yan-qiang Liu¹  Yu-xiang Wang²  Pan Li³ 

[1] College of Life Sciences, Nankai University, 300071, Tianjin, People’s Republic of China;Department of Immunology and Pathogenic Biology, School of Basic Medical Sciences, Hebei University of Chinese Medicine, 050200, Shijiazhuang, Hebei, People’s Republic of China;Tianjin Key Laboratory of Cerebral Vascular and Neurodegenerative Diseases, Tianjin Neurosurgery Institute, Department of Neurology, Tianjin Huanhu Hospital Affiliated to Nankai University, Tianjin, People’s Republic of China;

关键词: TPEN;    Aβ;    Zinc ions;    Channel currents;    Voltage-gated sodium channels;    Voltage-gated potassium channels;   

DOI  :  10.1186/s13041-021-00837-z

来源: Springer

【 摘 要 】

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.

【 授权许可】

CC BY