1
|
Ayanwuyi L, Tokarska N, McLean NA, Johnston JM, Verge VMK. Brief electrical nerve stimulation enhances intrinsic repair capacity of the focally demyelinated central nervous system. Neural Regen Res 2021; 17:1042-1050. [PMID: 34558531 PMCID: PMC8552867 DOI: 10.4103/1673-5374.324848] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Our lab has shown that brief electrical nerve stimulation (ES) has a dramatic impact on remyelination of lysophosphatidyl choline (LPC)-induced focally demyelinated rat peripheral nerves, while also inducing an axon-protective phenotype and shifting macrophages from a predominantly pro-inflammatory toward a pro-repair phenotype. Whether this same potential exists in the central nervous system is not known. Thus, for proof of principle studies, the peripheral nerve demyelination and ES model was adapted to the central nervous system, whereby a unilateral focal LPC-induced demyelination of the dorsal column at the lumbar enlargement where the sciatic nerve afferents enter was created, so that subsequent ipsilateral sciatic nerve ES results in increased neural activity in the demyelinated axons. Data reveal a robust focal demyelination at 7 days post-LPC injection. Delivery of 1-hour ES at 7 days post-LPC polarizes macrophages/microglia toward a pro-repair phenotype when examined at 14 days post-LPC; results in smaller LPC-associated regions of inflammation compared to non-stimulated controls; results in significantly more cells of the oligodendroglial lineage in the demyelinated region; elevates myelin basic protein levels; and shifts the paranodal protein Caspr along demyelinated axons to a more restricted distribution, consistent with reformation of the paranodes of the nodes of Ranvier. ES also significantly enhanced levels of phosphorylated neurofilaments detected in the zones of demyelination, which has been shown to confer axon protection. Collectively these findings support that strategies that increase neural activity, such as brief electrical stimulation, can be beneficial for promoting intrinsic repair following focal demyelinating insults in demyelinating diseases such as multiple sclerosis. All animal procedures performed were approved by the University of Saskatchewan's Animal Research Ethics Board (protocol# 20090087; last approval date: November 5, 2020).
Collapse
Affiliation(s)
- Lydia Ayanwuyi
- Department of Anatomy, Physiology and Pharmacology; Cameco MS Neuroscience Research Center, University of Saskatchewan, Saskatoon, SK, Canada
| | - Nataliya Tokarska
- Department of Anatomy, Physiology and Pharmacology; Cameco MS Neuroscience Research Center, University of Saskatchewan, Saskatoon, SK, Canada
| | - Nikki A McLean
- Department of Anatomy, Physiology and Pharmacology; Cameco MS Neuroscience Research Center, University of Saskatchewan, Saskatoon, SK, Canada
| | - Jayne M Johnston
- Department of Anatomy, Physiology and Pharmacology; Cameco MS Neuroscience Research Center, University of Saskatchewan, Saskatoon, SK, Canada
| | - Valerie M K Verge
- Department of Anatomy, Physiology and Pharmacology; Cameco MS Neuroscience Research Center, University of Saskatchewan, Saskatoon, SK, Canada
| |
Collapse
|
2
|
Chen M, Yang LL, Hu ZW, Qin C, Zhou LQ, Duan YL, Bosco DB, Wu LJ, Zhan KB, Xu SB, Tian DS. Deficiency of microglial Hv1 channel is associated with activation of autophagic pathway and ROS production in LPC-induced demyelination mouse model. J Neuroinflammation 2020; 17:333. [PMID: 33158440 PMCID: PMC7646080 DOI: 10.1186/s12974-020-02020-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 10/30/2020] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Multiple sclerosis (MS) is an immune-mediated demyelinated disease of the central nervous system. Activation of microglia is involved in the pathogenesis of myelin loss. OBJECTIVE This study is focused on the role of Hv1 in regulating demyelination and microglial activation through reactive oxygen species (ROS) production after lysophosphatidylcholine (LPC)-mediated demyelination. We also explored autophagy in this process. METHODS A model of demyelination using two-point LPC injection into the corpus callosum was established. LFB staining, immunofluorescence, Western blot, and electron microscopy were used to study the severity of demyelination. Microglial phenotype and autophagy were detected by immunofluorescence and Western blot. Morris water maze was used to test spatial learning and memory ability. RESULTS We have identified that LPC-mediated myelin damage was reduced by Hv1 deficiency. Furthermore, we found that ROS and autophagy of microglia increased in the demyelination region, which was also inhibited by Hv1 knockout. CONCLUSION These results suggested that microglial Hv1 deficiency ameliorates demyelination through inhibition of ROS-mediated autophagy and microglial phenotypic transformation.
Collapse
Affiliation(s)
- Man Chen
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, People's Republic of China
| | - Lin-Lin Yang
- Department of Neurology, Second Affiliated Hospital of University of South China, Hengyang, 421001, Hunan, People's Republic of China
| | - Zi-Wei Hu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, People's Republic of China
| | - Chuan Qin
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, People's Republic of China
| | - Luo-Qi Zhou
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, People's Republic of China
| | - Ya-Ling Duan
- Department of Neurology, Second Affiliated Hospital of University of South China, Hengyang, 421001, Hunan, People's Republic of China
| | - Dale B Bosco
- Department of Neurology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Long-Jun Wu
- Department of Neurology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Ke-Bin Zhan
- Department of Neurology, Second Affiliated Hospital of University of South China, Hengyang, 421001, Hunan, People's Republic of China.
| | - Sha-Bei Xu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, People's Republic of China.
| | - Dai-Shi Tian
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, People's Republic of China.
| |
Collapse
|