Deficiency of TREK‐1 potassium channel exacerbates secondary injury following spinal cord injury in mice. Issue 2 (15th March 2017)

• Record Type: Journal Article
• Authors: Fang, Yongkang; Huang, Xiaojiang; Wan, Yue; Tian, Hao; Tian, Yeye; Wang, Wei; Zhu, Suiqiang; Xie, Minjie
• Is Part Of: Journal of neurochemistry. Volume 141:Issue 2(2017)
• Page Start: 236
• Page End: 246
• Publication Date: 2017-03-15
• Subjects: glial scar -- inflammation -- remyelination -- spinal cord injury -- TREK‐1; Neurochemistry -- Periodicals; 616.8042
• DOI: 10.1111/jnc.13980
• Languages: English
• ISSNs: 0022-3042

Abstract

Abstract: Spinal cord injury (SCI) involves complex pathological process which can be complicated by secondary injury. TREK‐1 is a member of the two‐pore domain potassium (K2P) channel family, which can be modulated by a number of physiological and pathological stimuli. Recent studies suggest that TREK‐1 plays an active role in depression, pain and neuroprotection. However, its role in the pathological process after SCI remains unclear. In this study, we tested the expression and function of TREK‐1 in spinal cord of mice after traumatic SCI. TREK‐1 was widely expressed in mice spinal cord, including astrocytes and neurons. Deficiency of TREK‐1 significantly exacerbated focal inflammatory responses as indicated by the increased accumulation of microglia/macrophage as well as pro‐inflammatory factor interleukin‐1 beta (IL‐1β) and tumor necrosis factor alpha expression. Meanwhile, TREK‐1 knockout mice showed enhanced reactive astrogliosis, chondroitin sulphate proteoglycans (CSPGs) production and decreased glutamate transporter‐1 expression compared to the wide‐type mice after SCI. Furthermore, TREK‐1 deficiency promoted neurons and oligodendrocytes apoptosis, aggravated demyelination, cavity formation and retarded motor recovery. In summary, our findings provide the first in vivo evidence suggesting that TREK‐1 may thereby constitute a promising therapeutic target to treat acute SCI. Abstract : In normal conditions, TREK‐1 helps to set the negative membrane potential of astrocytes essential for GLT‐1 function and reduce neuronal excitability. TREK‐1 gene deficiency would contribute to glutamate‐mediated excitotoxicity and non‐permissive environment for axonal regeneration after SCI, which aggravate neurons and oligodendrocytes apoptosis, microglia‐induced inflammatory reaction and reactive astrogliosis. All the pathologic changes lead to extensive demyelination and neurologic impairment.