Background/Aims: miR-136-5p participates in recovery after spinal cord injury (SCI) via an unknown mechanism. We investigated the mechanism underlying the involvement of miR-136-5p in the inflammatory response in a rat model of SCI. Methods: Sprague-Dawley rat astrocytes were cultured in vitro to construct a reporter plasmid. Luciferase assays were used to detect the ability of miR-136-5p to target the IKKβ and A20 genes. Next, recombinant lentiviral vectors were constructed, which either overexpressed miR-136-5p or inhibited its expression. The influence of miR-136-5p overexpression and miR-136-5p silencing on inflammation was observed in vivo in an SCI rat model. The expression of IL-1β, IL-6, TNF-α, IFN-α, and related proteins (A20, IKKβ, and NF-κB) was detected. Results: In vitro studies showed that luciferase activity was significantly activated in the presence of the 3’ untranslated region (UTR) region of the IKKβ gene after stimulation of cells with miR-136-5p. However, luciferase activity was significantly inhibited in the presence of the 3’UTR region of the A20 gene. Thus, miR-136-5p may act directly on the 3’UTR regions of the IKKβ and A20 genes to regulate their expression. miR-136-5p overexpression promoted the production of related cytokines and NF-κB in SCI rats and inhibited the expression of A20 protein. Conclusion: Overexpression of miR-136-5p promotes the generation of IL-1β, IL-6, TNF-α, IFN-α, IKKβ, and NF-κB in SCI rats but inhibits the expression of A20. Under these conditions, inflammatory cell infiltration into the rat spinal cord increases and injury is significantly aggravated. Silencing of miR-136-5p significantly reduces the protein expression results described after miR-136-5p overexpression and ameliorates the inflammatory cell infiltration and damage to the spinal cord. Therefore, miR-136-5p might be a new target for the treatment of SCI.
Background/Aims: This study focused on investigating the regulatory mechanism of miR-136-5p in mouse astrocytes stimulated with interleukin-17(IL-17). Methods: C57BL/6 mouse astrocytes were stimulated with IL-17 (100ng/ml) for various periods of time (0-48 hours) and at various doses (0-200 ng), and the expression levels of inflammatory cytokine and chemokine genes (IL-6, TNF-α, MCP-1, MCP-5 and MIP-2) were then detected by real-time PCR. The expression of the A20 gene was measured with real-time PCR in cells that were stimulated with IL-17 (50 ng/ml) for various periods of time (0-48 hours). C57BL/6 mouse astrocytes were transfected with Ctrl-anti-miR-136-5p or LNA -anti-miR-136-5p for 48 h. Thereafter, the cells were stimulated with or without IL-17 (50ng/ml) for 6 h. The level of A20 protein (TNFα-induced protein 3, TNFAIP3) was detected by Western blot analysis. Results: (1) Compared with the DMEM control group, within six hours, IL-17 stimulation significantly increased the expression levels of inflammatory cytokine and chemokine genes and clearly decreased the expression level of the A20 protein. (2) Without IL-17 stimulation, the expression level of the miR-136-5p gene was significantly decreased, whereas in the miR-136-5p-inhibition group, the A20 protein expression was elevated. IL-17 stimulation slightly decreased the expression of the A20 protein in the miR-136-5p-inhibition group, but it was still slightly higher than in the control group. Conclusion: This study demonstrated that miR-136-5p affected the expression of A20 in IL-17-stimulated astrocytes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.