Exosome-shuttled miR-216a-5p from hypoxic preconditioned mesenchymal stem cells repair traumatic spinal cord injury by shifting microglial M1/M2 polarization

Bibliographic Details
Title: Exosome-shuttled miR-216a-5p from hypoxic preconditioned mesenchymal stem cells repair traumatic spinal cord injury by shifting microglial M1/M2 polarization
Authors: Wei Liu, Yuluo Rong, Jiaxing Wang, Zheng Zhou, Xuhui Ge, Chengyue Ji, Dongdong Jiang, Fangyi Gong, Linwei Li, Jian Chen, Shujie Zhao, Fanqi Kong, Changjiang Gu, Jin Fan, Weihua Cai
Source: Journal of Neuroinflammation, Vol 17, Iss 1, Pp 1-22 (2020)
Publisher Information: BMC, 2020.
Publication Year: 2020
Collection: LCC:Neurology. Diseases of the nervous system
Subject Terms: Spinal cord injury, Exosomes, Hypoxia, Microglia polarization, miR-216a-5p/TLR4 axis, Neurology. Diseases of the nervous system, RC346-429
More Details: Abstract Background Spinal cord injury (SCI) can lead to severe motor and sensory dysfunction with high disability and mortality. In recent years, mesenchymal stem cell (MSC)-secreted nano-sized exosomes have shown great potential for promoting functional behavioral recovery following SCI. However, MSCs are usually exposed to normoxia in vitro, which differs greatly from the hypoxic micro-environment in vivo. Thus, the main purpose of this study was to determine whether exosomes derived from MSCs under hypoxia (HExos) exhibit greater effects on functional behavioral recovery than those under normoxia (Exos) following SCI in mice and to seek the underlying mechanism. Methods Electron microscope, nanoparticle tracking analysis (NTA), and western blot were applied to characterize differences between Exos and HExos group. A SCI model in vivo and a series of in vitro experiments were performed to compare the therapeutic effects between the two groups. Next, a miRNA microarray analysis was performed and a series of rescue experiments were conducted to verify the role of hypoxic exosomal miRNA in SCI. Western blot, luciferase activity, and RNA-ChIP were used to investigate the underlying mechanisms. Results Our results indicate that HExos promote functional behavioral recovery by shifting microglial polarization from M1 to M2 phenotype in vivo and in vitro. A miRNA array showed miR-216a-5p to be the most enriched in HExos and potentially involved in HExos-mediated microglial polarization. TLR4 was identified as the target downstream gene of miR-216a-5p and the miR-216a-5p/TLR4 axis was confirmed by a series of gain- and loss-of-function experiments. Finally, we found that TLR4/NF-κB/PI3K/AKT signaling cascades may be involved in the modulation of microglial polarization by hypoxic exosomal miR-216a-5p. Conclusion Hypoxia preconditioning represents a promising and effective approach to optimize the therapeutic actions of MSC-derived exosomes and a combination of MSC-derived exosomes and miRNAs may present a minimally invasive method for treating SCI.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1742-2094
Relation: https://doaj.org/toc/1742-2094
DOI: 10.1186/s12974-020-1726-7
Access URL: https://doaj.org/article/e1b2b1fed81d474194e4fa0e4a37d9d7
Accession Number: edsdoj.1b2b1fed81d474194e4fa0e4a37d9d7
Database: Directory of Open Access Journals
Full text is not displayed to guests.
More Details
ISSN:17422094
DOI:10.1186/s12974-020-1726-7
Published in:Journal of Neuroinflammation
Language:English