Abstract
Background: Spinal cord ischemia reperfusion (IR) is associated with an inflammatory response. The long non-coding RNA (lncRNA) taurine upregulated gene 1 (TUG1) and microRNA-29b (miR-29b) family are frequently dysregulated in neuro-ischemic diseases. However, their potential roles in spinal cord IR injury (IR) are unknown. Methods: A spinal cord IR model was established in rats by14-minute occlusion of aortic arch. The aberrant miRNAs were identified by microarray analysis, and qRT-PCR was used to validate the lncRNA and microRNA levels. The motor function of the differentially-treated animals was assessed by Tarlov scores, and the leakage of Blood-spinal cord barrier (BSCB) was measured in terms of the extravasation of Evans blue (EB) dye. The expression levels of different proteins were analyzed by Western blotting and immunofluorescence. The interaction between TUG1 and miR-29b-1-5p, TRIL and miR-29b-1-5p, and MTDH and miR-29b-1-5p were determined using bioinformatics programs and the dual-luciferase reporter assay. Results: MiR-29b-1-5p was significantly downregulated and TUG1 was upregulated in the spinal cord of rats after IR. In addition, TRIL and MTDH protein levels were also significantly increased after IR. MTDH was predicted as a target of miR-29b-1-5p and its knockdown downregulated NF-κB and IL-1β levels. In addition, a direct interaction was observed between TUG1 and miR-29b-1-5p, and knocking down TUG1 upregulated the miRNA. Furthermore, overexpression of miR-29b-1-5p or TUG1 knockdown alleviated BSCB leakage and improved hind-limb motor function, and downregulated MTDH and its downstream pro-inflammatory cytokines. Suppression of miR-29b-1-5p reversed the neuroprotective effect of TUG1 knockdown, restored the levels of MTDH/ NF-κB/IL-1β and activated astrocytes. Conclusion: Downregulation of TUG1 alleviated MTDH/NF-κB/IL-1β pathway-mediated inflammatory damage after IR by targeting miR-29b-1-5p. Keywords: Spinal cord ischemia reperfusion injury, Neuroinflammation, Blood-spinal cord barrier, Astrocytes, TUG1, miR-29b-1-5p, MTDH
Correction to: Elevated microRNA-129-5p level ameliorates neuroinflammation and blood-spinal cord barrier damage after ischemia–reperfusion by inhibiting HMGB1 and the TLR3-cytokine pathway
