PMID- 36175984 OWN - NLM STAT- MEDLINE DCOM- 20221003 LR - 20221024 IS - 1757-6512 (Electronic) IS - 1757-6512 (Linking) VI - 13 IP - 1 DP - 2022 Sep 30 TI - miR-146a-5p-modified hUCMSC-derived exosomes facilitate spinal cord function recovery by targeting neurotoxic astrocytes. PG - 487 LID - 10.1186/s13287-022-03116-3 [doi] LID - 487 AB - BACKGROUND: Acute spinal cord injury (SCI) is a devastating result of neurological trauma with subsequent microenvironment dyshomeostasis that induces neurotoxic phenotype acquisition by astrocytes, exacerbating neurological function impairment. Exosomes derived from human umbilical cord mesenchymal stem cells (hUCMSCs) have demonstrated essential therapeutic effects after central nervous system trauma. However, whether hUCMSC-derived exosomes exert therapeutic effects on neurotoxic astrocytes to facilitate SCI function recovery remains unclear. Additionally, the limited efficiency of single exosomes may restrict the optimization of exosomal biological functions. METHODS: We first determined that exosomes reduce the deleterious effects of neurotoxic astrocytes in vitro and in vivo. Then, we identified critical functional microRNAs (miRNAs). miR-146a-5p was overexpressed in exosomes, and then, miR-146a-5p-modified exosomes were used to investigate the ability of exosomes to reduce neurotoxic astrocyte effects, preserve neurons and promote neurological function recovery in rats with SCI. RESULTS: Cell counting kit-8 and neurite length analyses revealed that exosomes partially reduced the negative effects of neurotoxic astrocytes on PC12 cell viability and neurites in vitro. The exosomes also attenuated inflammatory responses, reduced the number of neurotoxic astrocytes and preserved neural tissue in rats with SCI. Immunofluorescence assays suggested that the number of neurotoxic astrocytes was rapidly increased by injury, reaching a peak 5 days post-injury (dpi) and returning to the normal level 14dpi. Exosomal miR-146a-5p was identified as the critical functional miRNA. Overexpression of miR-146a-5p in exosomes strengthened the biological function of the exosomes. Therefore, the modified exosomes exerted more powerful therapeutic effects than the unmodified exosomes, reducing the deleterious effects of neurotoxic astrocytes both in vitro and in vivo and promoting locomotor function of the hindlimbs in the rats with SCI. Through a series of gain- and loss-of-function experiments, Traf6 and Irak1 were identified as targets of exosomal miR-146a-5p. Ultimately, we found that miR-146a-5p-modified exosomes exerted their function by targeting Traf6/Irak1/NFkappaB pathway in neurotoxic astrocytes. CONCLUSIONS: In summary, miR-146a-5p-modified exosomes exerted a more powerful effect than unmodified exosomes to promote neurological function recovery in rats with SCI by targeting neurotoxic astrocytes. Therefore, miR-146a-5p-modified exosomes are promising therapeutics for SCI. CI - (c) 2022. The Author(s). FAU - Lai, Xunwei AU - Lai X AD - Department of Spine Surgery, The Third Affiliated Hospital of Sun Yat-sen University, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. AD - National Medical Products Administration (NMPA) Key Laboratory for Quality Research and Evaluation of Cell Products, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. AD - Guangdong Provincial Center for Engineering and Technology Research of Minimally Invasive Spine Surgery, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. AD - Guangdong Provincial Center for Quality Control of Minimally Invasive Spine Surgery, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. FAU - Wang, Yang AU - Wang Y AD - Department of Spine Surgery, The Third Affiliated Hospital of Sun Yat-sen University, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. AD - National Medical Products Administration (NMPA) Key Laboratory for Quality Research and Evaluation of Cell Products, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. AD - Guangdong Provincial Center for Engineering and Technology Research of Minimally Invasive Spine Surgery, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. AD - Guangdong Provincial Center for Quality Control of Minimally Invasive Spine Surgery, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. FAU - Wang, Xiaokang AU - Wang X AD - Department of Spine Surgery, The Third Affiliated Hospital of Sun Yat-sen University, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. AD - National Medical Products Administration (NMPA) Key Laboratory for Quality Research and Evaluation of Cell Products, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. AD - Guangdong Provincial Center for Engineering and Technology Research of Minimally Invasive Spine Surgery, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. AD - Guangdong Provincial Center for Quality Control of Minimally Invasive Spine Surgery, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. FAU - Liu, Bin AU - Liu B AD - Department of Spine Surgery, The Third Affiliated Hospital of Sun Yat-sen University, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. AD - National Medical Products Administration (NMPA) Key Laboratory for Quality Research and Evaluation of Cell Products, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. AD - Guangdong Provincial Center for Engineering and Technology Research of Minimally Invasive Spine Surgery, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. AD - Guangdong Provincial Center for Quality Control of Minimally Invasive Spine Surgery, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. FAU - Rong, Limin AU - Rong L AUID- ORCID: 0000-0002-4049-870X AD - Department of Spine Surgery, The Third Affiliated Hospital of Sun Yat-sen University, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. ronglm@mail.sysu.edu.cn. AD - National Medical Products Administration (NMPA) Key Laboratory for Quality Research and Evaluation of Cell Products, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. ronglm@mail.sysu.edu.cn. AD - Guangdong Provincial Center for Engineering and Technology Research of Minimally Invasive Spine Surgery, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. ronglm@mail.sysu.edu.cn. AD - Guangdong Provincial Center for Quality Control of Minimally Invasive Spine Surgery, No. 600 Tianhe Road, Tianhe District, Guangzhou, Guangdong Province, China. ronglm@mail.sysu.edu.cn. LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't DEP - 20220930 PL - England TA - Stem Cell Res Ther JT - Stem cell research & therapy JID - 101527581 RN - 0 (MicroRNAs) RN - 0 (TNF Receptor-Associated Factor 6) SB - IM MH - Animals MH - *Astrocytes/metabolism MH - *Exosomes/genetics MH - *MicroRNAs/genetics/therapeutic use MH - Rats MH - Recovery of Function MH - Spinal Cord/metabolism MH - *Spinal Cord Injuries/therapy MH - TNF Receptor-Associated Factor 6 PMC - PMC9524140 OTO - NOTNLM OT - Modified exosomes OT - Neurotoxic astrocytes OT - Spinal cord injury OT - miR-146a-5p/Traf6/Irak1 axis COIS- The authors declare that they have no competing interests. EDAT- 2022/09/30 06:00 MHDA- 2022/10/04 06:00 PMCR- 2022/09/30 CRDT- 2022/09/29 23:54 PHST- 2022/04/07 00:00 [received] PHST- 2022/08/04 00:00 [accepted] PHST- 2022/09/29 23:54 [entrez] PHST- 2022/09/30 06:00 [pubmed] PHST- 2022/10/04 06:00 [medline] PHST- 2022/09/30 00:00 [pmc-release] AID - 10.1186/s13287-022-03116-3 [pii] AID - 3116 [pii] AID - 10.1186/s13287-022-03116-3 [doi] PST - epublish SO - Stem Cell Res Ther. 2022 Sep 30;13(1):487. doi: 10.1186/s13287-022-03116-3.