scholarly journals Long noncoding RNA MALAT1 contributes to inflammatory response of microglia following spinal cord injury via the modulation of a miR-199b/IKKβ/NF-κB signaling pathway

2018 ◽  
Vol 315 (1) ◽  
pp. C52-C61 ◽  
Author(s):  
Heng-Jun Zhou ◽  
Li-Qing Wang ◽  
Duan-Bu Wang ◽  
Jian-Bo Yu ◽  
Yu Zhu ◽  
...  

Long noncoding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) was widely recognized to be implicated in human cancer, vascular diseases, and neurological disorders. This study was to explore the role and underlying mechanism of MALAT1 in acute spinal cord injury (ASCI). ASCI models in adult rats were established and demonstrated by a numerical decrease in BBB scores. Expression profile of MALAT1 and miR-199b following ASCI in rats and in vitro was determined using quantitative real-time PCR. RNA pull-down assays combined with RIP assays were performed to explore the interaction between MALAT1 and miR-199b. In the present study, MALAT1 expression was significantly increased (2.4-fold that of control) in the spinal cord of the rat contusion epicenter accompanied by activation of IKKβ/NF-κB signaling pathway and an increase in the level of proinflammatory cytokines TNF-α and IL-1β. Upon treatment with LPS, MALAT1 expression dramatically increased in the microglia in vitro, but knockdown of MALAT1 attenuated LPS-induced activation of MGs and TNF-α and IL-1β production. Next, we confirmed that LPS-induced MALAT1 activated IKKβ/NF-κB signaling pathway and promoted the production of proinflammatory cytokines TNF-α and IL-1β through downregulating miR-199b. More importantly, MALAT1 knockdown gradually improved the hindlimb locomotor activity of ASCI rats as well as inhibited TNF-α, IL-1β levels, and Iba-1 protein, the marker of activated microglia in injured spinal cords. Our study demonstrated that MALAT1 was dysregulated in ASCI rats and in LPS-activated MGs, and MALAT1 knockdown was expected to attenuate ASCI through repressing inflammatory response of MGs.

2018 ◽  
Vol 50 (2) ◽  
pp. 512-524 ◽  
Author(s):  
Guiying Deng ◽  
Yunbing Gao ◽  
Zhongxi Cen ◽  
Jichen He ◽  
Baichuan Cao ◽  
...  

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.


2017 ◽  
Vol 43 (2) ◽  
pp. 481-491 ◽  
Author(s):  
Yihui Bi ◽  
Yapeng Zhu ◽  
Mingkai Zhang ◽  
Keke Zhang ◽  
Xingyi Hua ◽  
...  

Background/Aims: Shikonin, a compound extracted from Zicao, has been demonstrated to hold anti-bacterial, anti-inflammatory, and anti-tumor activities in various diseases and it has been shown to protect human organs from injuries. However, the effect of shikonin on the recovery of spinal cord injury (SCI) remains unknown. This study was designed to estimate the potential therapeutic effect and underlying mechanism of shikonin on SCI in vivo. Methods: In the study, we used HE staining, ELISA assay, transfection assay, TUNEL assay, real time PCR and Western blot to detect the effects of shikonin on spinal cord injury in rats. Results: we showed that shikonin could promote the recovery of motor function and tissue repair after SCI treatment in rats SCI model. Moreover, we demonstrated that shikonin inhibited the spinal cord edema in SCI model of rats. According to further investigation, shikonin induced the reduction of inflammatory response through decreasing the expression levels of HMGB1, TLR4 and NF-κB after SCI injury. In addition, we also found that shikonin could suppress the apoptosis and expression of caspase-3 protein in SCI model of rats. Conclusion: Our results demonstrated that shikonin induced the recovery of tissue repair and motor function via inactivation of HMGB1/TLR4/NF-κB signaling pathway in SCI model of rats. Meanwhile, shikonin regulated the inflammation response in SCI by suppressing the HMGB1/TLR4/NF-κB signaling pathway. The described mechanism sheds novel light on molecular signaling pathway in spinal cord injury and secondary injury including inflammatory response.


Inflammation ◽  
2020 ◽  
Vol 43 (4) ◽  
pp. 1536-1547 ◽  
Author(s):  
Minghao Shao ◽  
Mingming Jin ◽  
Shun Xu ◽  
Chaojun Zheng ◽  
Wei Zhu ◽  
...  

2021 ◽  
Author(s):  
Jialong Qi ◽  
Tao Wang ◽  
Zhidong Zhang ◽  
Zongsheng Yin ◽  
Yiming Liu ◽  
...  

Study design: Spinal cord injury (SCI) rat model and cell model were established for in vivo and in vitro experiments. Functional assays were utilized to explore the role of the circRNAs derived from catenin beta 1 (mmu_circ_0001859, circ-Ctnnb1 herein) in regulating neuronal cell viability and apoptosis. Bioinformatics analysis and mechanism experiments were conducted to assess the underlying molecular mechanism of circ-Ctnnb1. Objective: We aimed to probe into the biological function of circ-Ctnnb1 in neuronal cells of SCI. Methods: The rat model of SCI and hypoxia-induced cell model were constructed to examine circ-Ctnnb1 expression in SCI through quantitative reverse transcription real-time polymerase chain reaction (RT-qPCR). Basso, Beattie and Bresnahan (BBB) score was utilized for evaluating the neurological function. Terminal-deoxynucleoitidyl Transferase Mediated Nick End labeling (TUNEL) assays were performed to assess the apoptosis of neuronal cells. RNase R and Actinomycin D (ActD) were used to treat cells to evaluate the stability of circ-Ctnnb1. Results: Circ-Ctnnb1 was highly expressed in SCI rat models and hypoxia-induced neuronal cells, and its deletion elevated the apoptosis rate of hypoxia-induced neuronal cells. Furthermore, circ-Ctnnb1 activated the Wnt/β-catenin signaling pathway via sponging mircoRNA-205-5p (miR-205-5p) to up-regulate Ctnnb1 and Wnt family member 2B (Wnt2b). Conclusion: Circ-Ctnnb1 promotes SCI through regulating Wnt/β-catenin signaling via modulating the miR-205-5p/Ctnnb1/Wnt2b axis.


2014 ◽  
Vol 11 (1) ◽  
pp. 6 ◽  
Author(s):  
Irene Paterniti ◽  
Daniela Impellizzeri ◽  
Rosanna Di Paola ◽  
Emanuela Esposito ◽  
Stacy Gladman ◽  
...  

2019 ◽  
Vol 39 (12) ◽  
Author(s):  
Zhouliang Ren ◽  
Weidong Liang ◽  
Jun Sheng ◽  
Chuanhui Xun ◽  
Tao Xu ◽  
...  

Abstract Spinal cord injury (SCI) often occurs in young and middle-aged population. The present study aimed to clarify the function of Galectin-3 (Gal-3) in neuroinflammation of SCI. Sprague–Dawley (SD) rat models with SCI were established in vivo. PC12 cell model in vitro was induced by lipopolysaccharide (LPS). Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Gene chip were used to analyze the expression levels of genes in the signaling pathway. Histological assessment, ELISA and Western blotting were conducted to evaluate the effects of Gal-3 upon the SCI model. In the in vivo SD rat model, Gal-3 expression level was up-regulated. The inhibition of Gal-3 attenuated the neuroinflammation in SCI model. The inhibition of Gal-3 could also mitigate the neuroinflammation and reactive oxygen species (ROS) in in vitro model. ROS reduced the effect of Gal-3 on oxidative stress in in vitro model. Down-regulating the content of TXNIP decreased the effect of Gal-3 on neuroinflammation in in vitro model. Suppressing the level of NLRP3 could weaken the effect of Gal-3 on neuroinflammation in in vitro model. Our data highlight that the Gal-3 plays a vital role in regulating the severity of neuroinflammation of SCI by enhancing the activation of ROS/TXNIP/NLRP3 signaling pathway. In addition, inflammasome/IL-1β production probably acts as the therapeutic target in SCI.


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Feng Sun ◽  
Haiwei Zhang ◽  
Jianhui Shi ◽  
Tianwen Huang ◽  
Yansong Wang

Spinal cord injury (SCI) is a catastrophic disease that induces a complex cascade of cellular reactions at the local lesion area, including secondary cell death and inflammatory reactions. Accumulating evidence has showed pro- and anti-inflammatory roles of microRNAs (miRNAs), a class of small RNAs, in SCI. The present study is aimed at investigating the effects of two miRNAs, miRNA-146a and miRNA-202-3p, on inflammatory response after SCI. Initially, we found that the expression levels of miRNA-146a and miRNA-202-3p were increased in the plasma samples of 32 SCI patients at days 3 and 7 after admission and the rat spinal cord at days 3 and 7 after SCI modeling compared with healthy controls and sham-operated rats, respectively. The expression levels of TLR4, IRAK1, and TRAF6 were declined in the rat spinal cord at days 1, 3, and 7 after SCI modeling compared with sham-operated rats. Injection of miRNA-146a mimic or miRNA-202-3p mimic decreased TLR4, IRAK1, and TRAF6 expressions in the rat spinal cord at days 1, 3, and 7 after SCI modeling, while injection of miRNA-146a antagomir or miRNA-202-3p antagomir produced opposed results. Subsequent results showed that the expression levels of tumor necrosis factor-α (TNF-α), IL-1β, IL-6, and IL-8 were upregulated in the rat serum at days 1, 3, and 7 after SCI modeling compared with sham-operated rats. Injection of miRNA-146a mimic or miRNA-202-3p mimic decreased TNF-α, IL-1β, IL-6, and IL-8 expression levels in the rat serum at days 1, 3, and 7 after SCI modeling, while injection of miRNA-146a antagomir or miRNA-202-3p antagomir yielded opposed results. The expression levels of TNF-α, IL-1β, IL-6, and IL-8 were higher in the supernatants of PC12 cells transfected with anti-miRNA-146a or anti-miRNA-202-3p than in those transfected with si-TLR4, si-IRAK1, or si-TRAF6. These findings support the notion that miRNA-146a/miRNA-202-3p exerts anti-inflammatory functions after SCI.


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