Human PMSCs-derived small extracellular vesicles alleviate neuropathic pain through miR-26a-5p/Wnt5a in SNI mice model

Abstract

Background Mesenchymal stem cell (MSCs)-derived small Extracellular Vesicles (sEVs) are considered as a new cell-free therapy for pain caused by nerve injury, but whether human placental mesenchymal stem cell-derived sEVs relieve pain in sciatic nerve injury and its possible mechanism are still unclear. In this study, we investigated the roles of hPMSCs-derived sEVs and related mechanisms in neuropathic pain. Methods The spared nerve injury (SNI) mouse model was employed. Intrathecal injection of sEVs or miR-26a-5p agomir was performed on the seventh day of modeling, to study its anti-nociceptive effect. sEVs’ miRNA sequencing (miRNA-Seq) and bioinformatics analysis were performed to study the downstream mechanisms of miRNAs. RT-qPCR, protein assay and immunofluorescence were used for further validation. Results A single intrathecal injection of sEVs durably reversed mechanical hypersensitivity in the left hind paw of mice with partial sciatic nerve ligation. Immunofluorescence studies found that PKH26-labeled sEVs were visible in neurons and microglia in the dorsal horn of the ipsilateral L4/5 spinal cord and more enriched in the ipsilateral. According to miRNA-seq results, we found that intrathecal injection of miR-26a-5p agomir, the second high counts microRNA in hPMSCs derived sEVs, significantly suppressed neuropathic pain and neuroinflammation in SNI mice. Bioinformatics analysis and dual-luciferase reporter gene analysis identified Wnt5a as a direct downstream target gene of miR-26a-5p. The results showed that overexpression of miR-26a-5p in vivo could significantly reduce the expression level of Wnt5a. In addition, Foxy5, a mimetic peptide of Wnt5a, can significantly reverse the inhibitory effect of miR-26a-5p on neuroinflammation and neuropathic pain, and at the same time, miR-26a-5p can rescue the effect of Foxy5 by overexpression. Conclusions We reported that hPMSCs derived sEVs as a promising therapy for nerve injury induced neuropathic pain. In addition, we showed that the miR-26a-5p in the sEVs regulated Wnt5a/Ryk/CaMKII/NFAT partly take part in the analgesia through anti-neuroinflammation, which suggests an alleviating pain effect through non-canonical Wnt signaling pathway in neuropathic pain model in vivo.

Stem cell-derived extracellular vesicle-based therapy for nerve injury: A review of the molecular mechanisms

“… 49 In this regard, another study showed that a single intrathecal injection of the human placental mesenchymal stem cells (hPMSCs)-derived small extracellular vesicles durably reversed mechanical hypersensitivity and neuroinflammation through miR-26a-5p/Wnt5a in mice with partial sciatic nerve ligation. 50 Histological and functional evaluation of the crushed sciatic nerve after transplanting the gel containing human multipotent mesenchymal stromal cell-derived extracellular vesicles (MSCs-EVs) showed a significant decrease in apoptotic neuronal death and an increase in regeneration-associated proteins NF-200 and GAP-43, as well as a decrease in muscle atrophy. 51 Exosomes from Lipopolysaccharide (LPS)-preconditioned mesenchymal stem cells accelerated functional recovery, axon regeneration and remyelination through proinflammatory macrophage-to-progenitor macrophage transition.…”

The Primary Cilium and its Hedgehog Signaling in Nociceptors Contribute to Inflammatory and Neuropathic Pain

“…Of note, however, in contrast to the effect of Ift88 siRNA in control rats, which increased baseline mechanical nociceptive threshold in naïve control rats, inhibitors of Hh signaling in the absence of inflammation or peripheral neuropathy did not affect nociceptive threshold, supporting the presence of an Hh-independent primary cilium function capable of regulating baseline mechanical nociceptive threshold. Another primary cilium-dependent cellular signaling pathway that has been found to contribute to nociception is the wingless-related integration site (Wnt)/b-catenin signaling pathway [89][90][91][92][93][94][95] . Ciliary proteins are not only necessary for the regulation of certain types of Wnt signaling but also include effectors downstream of Wnt [96][97][98][99] .…”

MiR-31-5p regulates the neuroinflammatory response via TRAF6 in neuropathic pain

“…Elevated expression of miR-155-5p in the spinal cord contributed to mechanical hypersensitivity via the microglia inflammatory response of microglia in rats with bone cancer pain [ 9 ]. Furthermore, Miat promotes nerve injury-induced chronic pain through the miR-362-3p/BAMBI signaling axis pathway [ 10 ], and human placental mesenchymal stem cell-derived small extracellular vesicles have alleviated neuropathic pain via miR-26a-5p/Wnt5a in a mouse model of the spared nerve injury [ 11 ]. These studies indicated a tight association between miRNAs and neural pain.…”