Table 1.
Studies about MSC-derived exosomes and exosomal miRNAs in the treatment of SCI.
| Study | Animal | Exosomal miRNAs | Exosomes source | The route of administration | Mechanism of action | Biological function |
|---|---|---|---|---|---|---|
| Zhang et al. (2021) | SD rat | MiR-181c | BMSC | Tail vein injection | Upregulation of miR-181c inhibits the target gene PTEN which in turn inhibits the NF-κB signaling pathway and decreases the expression of microglial pro-inflammatory cytokines (TNF-α and IL-1β) | Reduce apoptosis and inflammation |
| Zhang et al. (2021) | SD rat | MiR-338–5p | BMSC | Tail vein and intrathecal injection | Upregulation of miR-338–5p represses target gene Cnr1 to regulate active Rap1 expression, activates PI3K/Akt pathway, attenuates Bax and caspase-3 expression, and up-regulates Bcl-2 expression | Reduce apoptosis and promote neuronal survival |
| Xiao et al. (2021) | SD rat | MiR-29b-3p | HucMSC | Tail vein injection | Upregulation of miR-29b-3p inhibits the PTEN axis while activating the Akt/mTOR pathway | Promote autophagy and axonal regeneration |
| Wang et al. (2021) | SD rat | MiR-199a-3p/145–5p | HucMSC | Tail vein injection | Upregulation of miR-199a-3p and miR-145–5p inhibit Cblb and Cbl, respectively, which in turn activate Akt and Erk in NGF/TrkA downstream pathways | Promote neuronal differentiation, reduce injury, and promote functional recovery |
| Jia et al. (2021) | SD rat | MiR-381 | BMSC | Tail vein injection | Upregulation of miR-381 inhibits the BRD4-WNT5A axis while inhibiting RhoA/Rho-kinase activity | Reduce apoptosis in dorsal root ganglia (DRG) |
| Chen et al. (2021) | SD rat | MiR-26a | BMSC | Tail vein injection | Upregulation of miR-26a inhibits the PTEN axis while activating the Akt/mTOR pathway | Reduce glial scar formation and promote axonal regeneration |
| Chang et al. (2021) | SD rat | MiR-125a | BMSC | Intrathecal injection | Upregulation of miR-125a inhibits the expression of target gene IRF5 | Inhibition of macrophage polarization to M1 type and secretion of proinflammatory cytokines |
| Liu et al. (2020) | Mice | MiR-216a-5p | BMSC | Tail vein injection | Upregulation of miR-216a-5p inhibits TLR4/NF-κB and activates the PI3K/AKT signaling pathway | Promote the microglial transition from M1 to M2 type |
| Li et al. (2020) | SD rat | MiR-124–3p | BMSC | Tail vein injection | Upregulation of miR-124–3p inhibits the expression of the target gene Ern1 | Promote macrophage polarization to M2 type |
| Li et al. (2020) | SD rat | MiR-544 | BMSC | Tail vein injection | Upregulation of miR-544 suppresses the expression of proinflammatory cytokines (IL-1a, TNF-a, IL-17B, and IL-36b) | Promote neuronal survival and suppresses inflammatory responses |
| Huang et al. (2020b) | SD rat | MiR-126 | BMSC | Tail vein injection | Upregulation of miR-126 inhibits the expression of SPRED1 and PIK3R2 | Promote angiogenesis and neurogenesis and reduces apoptosis |
| Zhou et al. (2019) | Wistar rat | MiR-21–5p | BMSC | Tail vein injection | Upregulation of miR-21–5p inhibits the expression of target gene Fasl | Reduce apoptosis |
| Yu et al. (2019) | SD rat | MiR-29b | BMSC | Tail vein injection | Upregulation of miR-29b promotes the expression of NF200, GAP-43, and inhibits the expression of GFAP | Promote neuronal regeneration and reduce injury |
| Kang et al. (2019) | SD rat | MiR-21 | BMSC | Tail vein injection | Upregulation of miR-21 inhibits the expression of PTEN and PDCD4 | Inhibition of cell death |
| Li et al. (2018) | SD rat | MiR-133b | BMSC | Tail vein injection | Upregulation of miR-133b inhibits the expression of the target gene RhoA and promotes the expression of ERK1/2, CREB, and STAT3 | Inhibit neuronal cell death and enhance axonal regeneration |
| Ren et al. (2019) | SD rat | MiR-133b | ADSC | - | Upregulation of miR-133b inhibits the expression of the target gene RhoA and promotes the expression of CREB, STAT3, NF, GAP-43, GFAP, and MBP | Inhibit neuronal cell death and enhance axonal regeneration and neuronal survival |