scholarly journals Downregulation of long noncoding RNA DLEU1 attenuates hypersensitivity in chronic constriction injury-induced neuropathic pain in rats by targeting miR-133a-3p/SRPK1 axis

2020 ◽  
Vol 26 (1) ◽  
Author(s):  
Zhen Li ◽  
Aiyuan Li ◽  
Liping Yan ◽  
Tian Yang ◽  
Wei Xu ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Neuropathic Pain ◽  
Noncoding Rna ◽  
Target Genes ◽  
Luciferase Reporter ◽  
Enzyme Linked Immunosorbent Assay ◽  
Withdrawal Threshold ◽  
Downstream Target ◽  
Tnf Α ◽  
Close Relationship

Abstract Background Neuropathic pain belongs to chronic pain and is caused by the primary dysfunction of the somatosensory nervous system. Long noncoding RNAs (lncRNAs) have been reported to regulate neuronal functions and play significant roles in neuropathic pain. DLEU1 has been indicated to have close relationship with neuropathic pain. Therefore, our study focused on the significant role of DLEU1 in neuropathic pain rat models. Methods We first constructed a chronic constrictive injury (CCI) rat model. Paw withdrawal threshold (PWT) and paw withdrawal latency (PWL) were employed to evaluate hypersensitivity in neuropathic pain. RT-qPCR was performed to analyze the expression of target genes. Enzyme-linked immunosorbent assay (ELISA) was conducted to detect the concentrations of interleukin‐6 (IL-6), tumor necrosis factor‐α (TNF-α) and IL-1β. The underlying mechanisms of DLEU1 were investigated using western blot and luciferase reporter assays. Results Our findings showed that DLEU1 was upregulated in CCI rats. DLEU1 knockdown reduced the concentrations of IL‐6, IL‐1β and TNF‐α in CCI rats, suggesting that neuroinflammation was inhibited by DLEU1 knockdown. Besides, knockdown of DLEU1 inhibited neuropathic pain behaviors. Moreover, it was confirmed that DLEU1 bound with miR-133a-3p and negatively regulated its expression. SRPK1 was the downstream target of miR-133a-3p. DLEU1 competitively bound with miR-133a-3p to upregulate SRPK1. Finally, rescue assays revealed that SRPK1 overexpression rescued the suppressive effects of silenced DLEU1 on hypersensitivity in neuropathic pain and inflammation of spinal cord in CCI rats. Conclusion DLEU1 regulated inflammation of the spinal cord and mediated hypersensitivity in neuropathic pain in CCI rats by binding with miR-133a-3p to upregulate SRPK1 expression.

Long Noncoding RNA SNHG1 Promotes Lipopolysaccharide-Induced Activation and Inflammation in Microglia via Targeting miR-181b

2021 ◽  
pp. 1-11
Author(s):  
Jun Dong ◽  
Tingkai Fu ◽  
Yunxue Yang ◽  
Zhenxin Mu ◽  
Xingang Li
Keyword(s):  
Inflammatory Cytokines ◽  
Long Noncoding Rna ◽  
Calcium Binding ◽  
Noncoding Rna ◽  
Morphological Changes ◽  
Luciferase Reporter ◽  
Enzyme Linked Immunosorbent Assay ◽  
Inflammation Response ◽  
Tnf Α ◽  
Cox 2

<b><i>Introduction:</i></b> Long noncoding RNA small nuclear host gene 1 (SNHG1) was involved in neuroinflammation in microglial BV-2 cells; however, its interaction with microRNA (miR)-181b in lipopolysaccharide (LPS)-induced BV-2 cells remained poor. <b><i>Methods:</i></b> BV-2 cells were treated with LPS and then were subjected to observation on morphology and immunofluorescence staining. After transfection, levels of inflammatory cytokines interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α) were determined with enzyme-linked immunosorbent assay (ELISA). The potential binding sites between SNHG1 and miR-181b were confirmed using dual-luciferase reporter assay. Quantitative real-time polymerase chain reaction and Western blot were applied for detecting the mRNA and protein expressions of proinflammatory cytokines, ionized calcium-binding adapter molecule 1 (Iba1), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS). <b><i>Results:</i></b> LPS led to the morphological changes and activation of BV-2 cells. The transfection of SNHG1 overexpression vector further promoted LPS-induced SNHG1 upregulation, inflammatory cytokines (IL-1β, IL-6, and TNF-α) generation and Iba-1, COX-2, and iNOS expressions, whereas silencing SNHG1 did the opposite. miR-181b functions as a downstream miRNA of SNHG1. In LPS-treated cells, the inhibition of miR-181b induced by SNHG1 promoted inflammation response and the expressions of Iba-1, COX-2, and iNOS. <b><i>Conclusion:</i></b> SNHG1 was involved in LPS-induced microglial activation and inflammation response via targeting miR-181b, providing another evidence of the roles of SNHG1 implicated in neuroinflammation of microglia.

LncRNA PCAT19 Regulates Neuropathic Pain via Regulation of miR-182-5p/JMJD1A in a Rat Model of Chronic Constriction Injury

2021 ◽  
pp. 1-9
Author(s):  
Miao Huo ◽  
Xingxing Zheng ◽  
Ning Bai ◽  
Ruifen Xu ◽  
Guang Yang ◽  
...  
Keyword(s):  
Neuropathic Pain ◽  
Rat Model ◽  
Noncoding Rna ◽  
Thermal Hyperalgesia ◽  
Luciferase Reporter Assay ◽  
Luciferase Reporter ◽  
Inflammatory Factor ◽  
Reporter Assay ◽  
Withdrawal Threshold ◽  
Dual Luciferase Reporter Assay

<b><i>Introduction:</i></b> Neuropathic pain (NP) is one of the most severe chronic pain types. In recent years, more and more studies have shown that long noncoding RNA (LncRNA) plays a key role in a variety of human diseases, including NP. However, the role of LncRNA prostate cancer-associated transcript 19 (PCAT19) in NP and its specific mechanism remain unclear. <b><i>Methods:</i></b> A chronic constrictive injury (CCI) rat model was established. Rat paw withdrawal threshold and paw withdrawal latency were used to evaluate the neuronal pain behavior of rats in this model. mRNA expression of PCAT19, neuroinflammatory factor, microRNA (miR)-182-5p, and Jumonji domain containing 1A (JMJD1A) were detected by quantitative real-time PCR. ELISA analysis was used to detect inflammatory factor protein expression. Dual-luciferase reporter assay was used to evaluate the targeting relationship between genes. <b><i>Results:</i></b> PCAT19 was continuously upregulated in CCI rats. miR-182-5p was the target of PCAT19, and miR-182-5p was increased after PCAT19 knockdown. NP behaviors such as mechanical ectopic pain and thermal hyperalgesia as well as neuroinflammation can be reduced by knocking down PCAT19. However, the injection of miR-182-5p antagomir significantly reversed the level of the NP behaviors and neuroinflammation caused by PCAT19 knockdown. Besides, dual-luciferase reporter assay showed that JMJD1A was the target gene of miR-182-5p. The level of JMJD1A in CCI rats increased with time. After PCAT19 knockdown, JMJD1A was significantly decreased, but inhibition of miR-182-5p can reverse its levels. <b><i>Conclusion:</i></b> This study shows that PCAT19 plays a role in NP by targeting the miR-182-5p/JMJD1A axis, and PCAT19 can be used as a new therapeutic target for NP.

Downregulation of Long Noncoding RNA TUG1 Attenuates MTDH-Mediated Inflammatory Damage via Targeting miR-29b-1-5p After Spinal Cord Ischemia Reperfusion

2020 ◽  
Author(s):  
Hui Jia ◽  
Zhe Li ◽  
Yi Chang ◽  
Bo Fang ◽  
Yongjian Zhou ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Noncoding Rna ◽  
Target Genes ◽  
Neuroprotective Effect ◽  
Ischemia Reperfusion ◽  
Spinal Cord Ischemia ◽  
Specific Inhibitor ◽  
Direct Interaction ◽  
Luciferase Reporter ◽  
Inflammatory Damage

Abstract Long noncoding RNAs and microRNAs (miRNAs) play a vital role in spinal cord ischemia reperfusion (IR) injury. The aim of this study was to identify the potential interactions between taurine upregulated gene 1 (TUG1) and miRNA-29b-1-5p in a rat model of spinal cord IR. The IR injury was established by 14-minute occlusion of aortic arch. TUG1 and metadherin (MTDH) knockdown were induced by respective siRNAs, and miR-29b-1-5p expression was modulated using specific inhibitor or mimics. The interactions between TUG1, miR-29b-1-5p, and the target genes were determined using the dual-luciferase reporter assay. We found that IR respectively downregulated and upregulated miR-29b-1-5p and TUG1, and significantly increased MTDH expression. MTDH was predicted as a target of miR-29b-1-5p and its knockdown downregulated NF-κB and IL-1β levels. A direct interaction was observed between TUG1 and miR-29b-1-5p, and knocking down TUG1 upregulated the latter. Furthermore, overexpression of miR-29b-1-5p or knockdown of TUG1 alleviated blood-spinal cord barrier leakage and improved hind-limb motor function by suppressing MTDH and its downstream pro-inflammatory cytokines. Knocking down TUG1 also alleviated MTDH/NF-κB/IL-1β pathway-mediated inflammatory damage after IR by targeting miR-29b-1-5p, whereas blocking the latter reversed the neuroprotective effect of TUG1 knockdown and restored MTDH/NF-κB/IL-1β levels.

Lidocaine activates autophagy of astrocytes and ameliorates chronic constriction injury-induced neuropathic pain

2020 ◽  
Author(s):  
Jiaqi Yuan ◽  
Yue Fei
Keyword(s):  
Cell Proliferation ◽  
Neuropathic Pain ◽  
Chronic Constriction Injury ◽  
Enzyme Linked Immunosorbent Assay ◽  
Inflammatory Factor ◽  
Experimental Basis ◽  
Withdrawal Threshold ◽  
Withdrawal Latency ◽  
Tnf Α ◽  
Rat Astrocytes

Abstract Lidocaine is a commonly used drug to alleviate neuropathic pain (NP). This work aims to investigate the mechanism of lidocaine in alleviating NP. Chronic constriction injury (CCI) rats were established by surgery to induce NP. We observed the mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) of rats. Immunofluorescence staining was performed to determine the LC3/glial fibrillary acidic protein (GFAP)-positive cells. Rat astrocytes were treated with lipopolysaccharide (LPS) to induce CCI, and then treated with lidocaine or 3-MA (autophagy inhibitor). CCK-8 was performed to detect cell proliferation. Western blot and enzyme-linked immunosorbent assay were performed to detect the level of protein and inflammatory factor. CCI rats exhibited a decrease of MWT and TWL, which was effectively abolished by lidocaine. Lidocaine enhanced the number of LC3/GFAP-positive cells in CCI rats. Moreover, lidocaine inhibited the expression of GFAP and p62, and enhanced LC3-II/LC3-I expression in the LPS-treated astrocytes. Lidocaine inhibited the level of TNF-α and IL-1β in the LPS-treated astrocytes. The influence conferred by lidocaine was effectively abolished by 3-MA. In conclusion, our work demonstrates that lidocaine activates autophagy of astrocytes and ameliorates CCI-induced NP. Thus, our study provides a further experimental basis for the mechanism of lidocaine to alleviate NP.

scholarly journals Hydrogen-Rich Saline Activated Autophagy via HIF-1α Pathways in Neuropathic Pain Model

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Huixing Wang ◽  
Xiaodong Huo ◽  
Hongguang Chen ◽  
Bo Li ◽  
Jingzhi Liu ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Neuropathic Pain ◽  
Intractable Pain ◽  
Sprague Dawley ◽  
Pain Model ◽  
Withdrawal Threshold ◽  
Downstream Target ◽  
Cord Injury ◽  
Neuropathic Pain Model ◽  
Regulatory Effects

Background. Neuropathic pain is a chronic and intractable pain, with very few effective analgesics. It involves an impaired cell autophagy process. Hydrogen-rich saline (HRS) reportedly reduces allodynia and hyperalgesia in a neuropathic pain model; however, it is unknown whether these effects involve autophagy induction. Methods. We investigated the relationship between HRS and cell autophagy in a neuropathic pain model generated by chronic constriction injury (CCI) in Sprague–Dawley rats. Rats received an intraperitoneal injection of HRS (10 mL/kg daily, from 1 day before until 14 days after CCI), 3MA (autophagy inhibitor), 2ME2 (HIF-1α inhibitor), or EDHB (HIF-1α agonist). The mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were tested 1 day before and 1, 3, 7, 10, and 14 days after the operation. HIF-1α and cell autophagy markers in the spinal cord were evaluated by western blotting and real-time PCR assays at 14 days after CCI. Autophagosomes with double membranes were identified by transmission electron microscopy. Results. CCI caused behavioral hypersensitivity to mechanical and thermal stimulation in the hind-paw of the injured side. HRS improved MWT and TWL, activated autophagy, and increased autophagosomes and autolysosomes in CCI rats. 3-MA aggravated hyperalgesia and allodynia and suppressed autophagy, while EDHB attenuated hyperalgesia and activated the autophagy procedure and the HIF-1α downstream target gene BNIP3. HIF-1α inhibitors reversed the regulatory effects of HRS on autophagy in CCI rats at 14 days after spinal cord injury. Conclusion. HRS reduced mechanical hyperalgesia and activation of cell autophagy in neuropathic pain through a HIF1-dependent pathway.

scholarly journals N-Acetylcysteine Attenuates Hyperalgesia in Rats with Diabetic Neuropathic Pain: Role of Oxidative Stress and Inflammatory Mediators and CXCR4

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Sisi Li ◽  
Xuying Li ◽  
Xiangbin Xie ◽  
Xiao Wei ◽  
Cong Yu ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Neuropathic Pain ◽  
Prefrontal Cortex ◽  
Diabetic Rats ◽  
Sprague Dawley ◽  
Diabetic Neuropathic Pain ◽  
Withdrawal Threshold ◽  
Sprague Dawley Rats ◽  
Therapeutic Value ◽  
Tnf Α

Objectives. CXCR4 plays critical roles in the development of diabetic neuropathic pain (DNP) in rats, and its mechanism is unknown. This study was aimed at evaluating the potential therapeutic value of the antioxidant N-acetylcysteine (NAC) against DNP in rats and how CXCR4 participates in the formation of DNP. Methods. Control or streptozotocin- (STZ-) induced diabetic Sprague-Dawley rats received vehicle or NAC for four weeks starting one week after STZ injection. Von Frey and Hargreaves Apparatus were used to analyze the behavioral changes of mechanical allodynia and heat hyperalgesia. CXCR4, p-CXCR4, interleukin- (IL-) 6, and tumor necrosis factor- (TNF-) α in the spinal cord and the prefrontal cortex were detected by western blotting. Plasma IL-6, TNF-α, superoxide dismutase- (SOD-) 1, SOD-2, and lipid peroxidation products malondialdehyde (MDA) and 15-F2t-Isoprostane were detected by ELISA. Results. The values of paw withdrawal threshold (PWT) and paw withdrawal latencies (PWL) were reduced in diabetic rats compared to control rats that were concomitant with significant increases of CXCR4, p-CXCR4, IL-6, and TNF-α protein expressions in the spinal cord and prefrontal cortex. The treatment with NAC decreased the IL-6 and TNF-α protein expression and further increased CXCR4 and p-CXCR4 in the spinal cord and the cortex of diabetic rats that were accompanied with enhancement of PWT and PWL. NAC also significantly attenuated or reverted the increases of plasma IL-6, TNF-α, SOD-1, SOD-2, MDA, and 15-F2t-Isoprostane in diabetic rats. Conclusion. It is concluded that NAC treatment could effectively alleviate DNP and that induction of CXCR4 and p-CXCR4 may represent a mechanism whereby NAC attenuates DNP.

scholarly journals Dezocine attenuates neuropathic pain by inhibiting ERK1/2 signaling in rats

2019 ◽  
Author(s):  
Chan Shen ◽  
Shi Sheng ◽  
Ling Yu ◽  
Naixing Xin
Keyword(s):  
Neuropathic Pain ◽  
Quantitative Polymerase Chain Reaction ◽  
Mammalian Target Of Rapamycin ◽  
Life Quality ◽  
Enzyme Linked Immunosorbent Assay ◽  
Control Group ◽  
Expression Levels ◽  
Withdrawal Threshold ◽  
Tnf Α ◽  
Cox 2

Abstract Background Neuropathic pain severely impacts patients’ life quality. Dezocine can be used for the treatment of pain. The present study intended to explore the effects of dezocine in chronic constriction injury (CCI) induced neuropathic pain as well as the possible responsible molecules in rats. Methods There were 3 subgroups, ie, control group, CCI group and dezocine+CCI group. The values of paw withdrawal threshold (PWT) and paw withdrawal latency (PWL) in rats were determined by a dynamic plantar esthesiometer. The ipsilateral lumbar spinal cords in rats were extracted for the detection of protein levels of phosphorylated-mammalian target of rapamycin (p-mTOR) and p-extracellular signal-regulated kinase 1/2 (p-ERK1/2) by western blot analysis; and the mRNA and protein expression levels of interleukin (IL)-6, tumor necrosis factor (TNF)-α, and cyclooxygenase-2 (COX-2) by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Results In comparison with control group, there were lower values of PWT and PWL in CCI group, which were partially reversed by dezocine. In addition, compared to control group, the expression levels of p-mTOR, p-ERK1/2, IL-6, TNF-α and COX-2 were upregulated by CCI, which were attenuated by dezocine. Conclusions In conclusion, the analgesic effect of dezocine on CCI induced neuropathic pain might be correlated with inhibiting of the p-mTOR and p-ERK1/2 signaling pathway.

Long noncoding RNA GAS5 ameliorates chronic constriction injury induced neuropathic pain in rats by modulation of the miR-452-5p/CELF2 axis

2020 ◽  
Vol 98 (12) ◽  
pp. 870-877
Author(s):  
Yingjie Tian ◽  
Li Sun ◽  
Tao Qi
Keyword(s):  
Nervous System ◽  
Neuropathic Pain ◽  
Noncoding Rna ◽  
Chronic Constriction Injury ◽  
Pain Treatment ◽  
Thermal Hyperalgesia ◽  
Spontaneous Pain ◽  
Downstream Target ◽  
Tnf Α ◽  
The Central Nervous System

Neuropathic pain is a type of spontaneous pain that causes damage to the central nervous system. Long noncoding RNAs (lncRNAs) participate in the progression of various nervous system diseases, including neuropathic pain. However, the biological function of GAS5 in neuropathic pain remains unclear. Our findings revealed that GAS5 was downregulated in chronic constriction injury (CCI) rats. Besides, ELISA showed that the concentration of IL‐6, TNF-α, and IL‐1β were reduced by overexpressed GAS5 in spinal cord homogenates of CCI rats. Moreover, mechanical allodynia and thermal hyperalgesia in CCI rats were inhibited by GAS5 overexpression, suggesting that GAS5 overexpression attenuated neuropathic pain. Subsequently, we found that GAS5 served as a sponge for miR-452-5p in CCI rats and CELF2 was the downstream target of miR-452-5p. Finally, through a rescue assay, we found that GAS5 ameliorated neuropathic pain in CCI rats by sponging miR-452-5p to regulate CELF2 expression. Our study confirmed that GAS5 ameliorated neuropathic pain in rats by modulation of the miR-452-5p/CELF2 axis, which may provide some clues for neuropathic pain treatment.

scholarly journals Long noncoding RNA SNHG14 promotes hepatocellular carcinoma progression by regulating miR-876-5p/SSR2 axis

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Zhibin Liao ◽  
Hongwei Zhang ◽  
Chen Su ◽  
Furong Liu ◽  
Yachong Liu ◽  
...  
Keyword(s):  
Noncoding Rna ◽  
Animal Experiments ◽  
Luciferase Reporter ◽  
Western Blot Assay ◽  
Downstream Target ◽  
Protein Levels ◽  
Elevated Expression ◽  
Rna Immunoprecipitation

Abstract Background Aberrant expressions of long noncoding RNAs (lncRNAs) have been demonstrated to be related to the progress of HCC. The mechanisms that SNHG14 has participated in the development of HCC are obscure. Methods Quantitative real-time PCR (qRT-PCR) was used to measure the lncRNA, microRNA and mRNA expression level. Cell migration, invasion and proliferation ability were evaluated by transwell and CCK8 assays. The ceRNA regulatory mechanism of SNHG14 was evaluated by RNA immunoprecipitation (RIP) and dual luciferase reporter assay. Tumorigenesis mouse model was used to explore the roles of miR-876-5p in vivo. The protein levels of SSR2 were measured by western blot assay. Results In this study, we demonstrated that SNHG14 was highly expressed in HCC tissues, meanwhile, the elevated expression of SNHG14 predicted poor prognosis in patients with HCC. SNHG14 promoted proliferation and metastasis of HCC cells. We further revealed that SNHG14 functioned as a competing endogenous RNA (ceRNA) for miR-876-5p and that SSR2 was a downstream target of miR-876-5p in HCC. Transwell, CCK8 and animal experiments exhibited miR-876-5p inhibited HCC progression in vitro and in vivo. By conducting rescue experiments, we found the overexpression of SSR2 or knocking down the level of miR-876-5p could reverse the suppressive roles of SNHG14 depletion in HCC. Conclusion SNHG14 promotes HCC progress by acting as a sponge of miR-876-5p to regulate the expression of SSR2 in HCC.

scholarly journals Short-chain fatty acids contribute to neuropathic pain via regulating microglia activation and polarization

2021 ◽  
Vol 17 ◽  
pp. 174480692199652
Author(s):  
Feng Zhou ◽  
Xian Wang ◽  
Baoyu Han ◽  
Xiaohui Tang ◽  
Ru Liu ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Neuropathic Pain ◽  
Thermal Hyperalgesia ◽  
Short Chain Fatty Acids ◽  
Antibiotic Administration ◽  
Tnf Α ◽  
Microglia Polarization ◽  
Inflammatory Phenotype ◽  
Phenotype Markers ◽  
Anti Inflammatory

Microglia activation and subsequent pro-inflammatory responses play a key role in the development of neuropathic pain. The process of microglia polarization towards pro-inflammatory phenotype often occurs during neuroinflammation. Recent studies have demonstrated an active role for the gut microbiota in promoting microglial full maturation and inflammatory capabilities via the production of Short-Chain Fatty Acids (SCFAs). However, it remains unclear whether SCFAs is involved in pro-inflammatory/anti-inflammatory phenotypes microglia polarization in the neuropathic pain. In the present study, chronic constriction injury (CCI) was used to induce neuropathic pain in mice, the mechanical withdrawal threshold, thermal hyperalgesia were accomplished. The levels of microglia markers including ionized calcium-binding adaptor molecule 1 (Iba1), cluster of differentiation 11b (CD11b), pro-inflammatory phenotype markers including CD68, interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and anti-inflammatory phenotype markers including CD206, IL-4 in the hippocampus and spinal cord were determined on day 21 after CCI. The results showed that CCI produced mechanical allodynia and thermal hyperalgesia, and also increased the expressions of microglia markers (Iba1, CD11b) and pro-inflammatory phenotype markers (CD68, IL-1β, and TNF-α), but not anti-inflammatory phenotype marker (CD206, IL-4) in the hippocampus and spinal cord, accompanied by increased SCFAs in the gut. Notably, antibiotic administration reversed these abnormalities, and its effects was also bloked by SCFAs administration. In conclusion, data from our study suggest that CCI can lead to mechanical and thermal hyperalgesia, while SCFAs play a key role in the pathogenesis of neuropathic pain by regulating microglial activation and subsequent pro-inflammatory phenotype polarization. Antibiotic administration may be a new treatment for neuropathic pain by reducing the production of SCFAs and further inhibiting the process of microglia polarization.

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