Selective removal of misfolded SOD1 delays disease onset in a mouse model of amyotrophic lateral sclerosis

Author:

Guan Teng1,Zhou Ting1,Zhang Xiaosha1,Guo Ying1,Yang Chaoxian1,Lin Justin1,Zhang Jiasi Vicky1,Cheng Yongquan1,Marzban Hassan1,Wang Yu-Tian2,Kong Jiming3ORCID

Affiliation:

1. University of Manitoba College of Medicine: University of Manitoba Max Rady College of Medicine

2. UBC: The University of British Columbia

3. University of Manitoba

Abstract

Abstract Background Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease. There is no cure currently. The discovery that mutations in the gene SOD1 are a cause of ALS marks a breakthrough for the search of effective treatments for ALS. SOD1 is an antioxidant that is highly expressed in motor neurons. Human SOD1 is prone to aberrant modifications. Familial ALS-linked SOD1 variants are particularly susceptible to aberrant modifications. Once modified, SOD1 undergoes conformational changes and becomes misfolded. This study aims to determine the effect of selective removal of misfolded SOD1 on the pathogenesis of ALS. Methods Based on chaperone-mediated protein degradation pathway, we designed a fusion peptide named CT4, and tested its efficiency in knocking down intracellularly misfolded SOD1 and its efficacy in modifying pathogenesis of ALS. Results Expression of plasmid carrying the CT4 sequence in human HEK cells resulted in robust removal of misfolded SOD1 induced by serum deprivation. Co-transfection of the CT4 and the human SOD1 G93A plasmids at various ratios in rat PC12 cells demonstrated a dose-dependent knockdown efficiency on G93A, which could be further increased when misfolding of SOD1 was enhanced by serum deprivation. Application of the full length CT4 peptide to primary cultures of neurons expressing the G93A variant of human SOD1 revealed a time-course of the degradation of misfolded SOD1; misfolded SOD1 started to decrease by 2 h after the application of CT4 and disappeared by 7 h. Intravenous administration of the CT4 peptide at 10 mg/kg to the G93A mice at the age of 4 months old induced reduction of human SOD1 in spinal cord tissue by 68% in 24 h and 54% in 48 h. Intraperitoneal administration of the CT4 peptide starting from 60 days of age significantly delayed the onset of ALS and prolonged the lifespan of the G93A mice. Conclusions The CT4 peptide directs degradation of misfolded SOD1 in high efficiency and specificity. Selective removal of misfolded SOD1 significantly delays the onset of ALS, demonstrating that misfolded SOD1 is the toxic form of SOD1 that causes motor neuron death. The study provides a proof of concept that selective removal of misfolded SOD1 is a promising treatment for ALS.

Publisher

Research Square Platform LLC

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3