Lentiviral-mediated Targeted NF-κB Blockade in Dorsal Spinal Cord Glia Attenuates Sciatic Nerve Injury–induced Neuropathic Pain in the Rat

Abstract Background: The importance of P2X purinoceptors, CB2 receptor and microRNA-124(miR-124) in spinal cord microglia to the development of neuropathic pain was demonstrated in numerous previous studies. The upregulation of P2X4 and P2X7 receptors in spinal dorsal horn microglia is involved in the development of pain behavior caused by peripheral nerve injury. However, it is not clear whether the expression of P2X4 and P2X7 receptors at dorsal spinal cord will be influenced by CB2 receptor or miR-124 in rats after chronic sciatic nerve injury.Methods: Chronic constriction injury (CCI) of the sciatic nerve was performed in rats to induce neuropathic pain. Tests of the mechanical withdrawal threshold (MWT) were carried out to assess the response of the paw to mechanical stimulus. The expression of miR-124, P2X4, P2X7 and CB2 receptor were detected with RT-PCR. The protein expression of P2X4, P2X7 and CB2 receptor, RhoA, ROCK1, ROCK2, p-p38MAPK and p-NF-kappaBp65 was detected with Western blotting analysis. Results: Intrathecal administration of CB2 receptor agonist AM1241 significantly attenuated CCI-induced mechanical allodynia and significantly inhibited the increased expression of P2X4 and P2X7 receptors at the mRNA and protein levels, which imply that P2X4 and P2X7 receptors expression are down-regulated by AM1241 in CCI rats. Western blot analysis showed that AM1241 suppressed the elevated expression of RhoA, ROCK1, ROCK2, p-p38MAPK and NF-κBp65 in the dorsal spinal cord induced by CCI. After administration with Y-27632 (ROCK inhibitor), SB203580 (P38MAPK inhibitor) or PDTC (NF-κB inhibitor), the levels of P2X4 and P2X7 receptors expression in the dorsal spinal cord were lower than those in CCI rats, which imply that the ROCK/P38MAPK pathway and NF-κB activation may contribute to the increased expression of P2X4 and P2X7 receptor. On the other hand, in CCI rats, AM1241 treatment evoked the increased expression of CB2 receptor and miRNA-124, which can be inhibited by intrathecal injection of CB2 receptor antagonist AM630, which indicate that the increased expression of miRNA-124 may be medicated by CB2 receptor activation. In addition, the increased expression of P2X4 and P2X7 receptors in the dorsal spinal cord of CCI rats were inhibited by miRNA-124 agomir. Furthermore, intrathecal injection of miRNA-124 agomir could efficiently inhibit the ROCK/P38MAPK pathway and NF-κB activation in CCI rats. Moreover, AM1241 treatment significantly inhibited the expression of P2X4 and P2X7 receptors, and this suppression is enhanced by pretreatment with miRNA-124 agomir. On the contrast, the inhibitory effect of AM1241 on the expression of P2X4 and P2X7 receptor can be reversed by pretreatment with miRNA-124 antagomir.Conclusions: In CCI rats, intrathecal injection of AM1241 could efficiently induce the increased expression of miRNA-124, while inhibiting the ROCK/P38MAPK pathway and NF-κB activation in dorsal spinal cord. CB2 receptor/miRNA-124 signaling induced the decreased P2X4 and P2X7 receptors expression via inhibit the ROCK/P38MAPK pathway and NF-κB activation.

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Comprehensive analysis of neurobehavior associated with histomorphological alterations in a chronic constrictive nerve injury model through use of the CatWalk XT system

Journal of Neurosurgery ◽

10.3171/2013.9.jns13353 ◽

2014 ◽

Vol 120 (1) ◽

pp. 250-262 ◽

Cited By ~ 26

Author(s):

Chien-Yi Chiang ◽

Meei-Ling Sheu ◽

Fu-Chou Cheng ◽

Chun-Jung Chen ◽

Hong-Lin Su ◽

...

Keyword(s):

Spinal Cord ◽

Neuropathic Pain ◽

Nerve Injury ◽

Mechanical Allodynia ◽

S100 Protein ◽

Thermal Hyperalgesia ◽

Nerve Damage ◽

Dorsal Spinal Cord ◽

Sensory Evoked ◽

Dorsal Spinal

Object Neuropathic pain is debilitating, and when chronic, it significantly affects the patient physically, psychologically, and socially. The neurobehavior of animals used as a model for chronic constriction injury seems analogous to the neurobehavior of humans with neuropathic pain. However, no data depicting the severity of histomorphological alterations of the nervous system associated with graded changes in neurobehavior are available. To determine the severity of histomorphological alteration related to neurobehavior, the authors created a model of chronic constrictive injury of varying intensity in rats and used the CatWalk XT system to evaluate neurobehavior. Methods A total of 60 Sprague-Dawley rats, weighing 250–300 g each, were randomly assigned to 1 of 5 groups that would receive sham surgery or 1, 2, 3, or 4 ligatures of 3-0 chromic gut loosely ligated around the left sciatic nerve. Neurobehavior was assessed by CatWalk XT, thermal hyperalgesia, and mechanic allodynia before injury and periodically after injury. The nerve tissue from skin to dorsal spinal cord was obtained for histomorphological analysis 1 week after injury, and brain evoked potentials were analyzed 4 weeks after injury. Results. Significant differences in expression of nerve growth factor existed in skin, and the differences were associated with the intensity of nerve injury. After injury, expression of cluster of differentiation 68 and tumor necrosis factor–α was increased, and expression of S100 protein in the middle of the injured nerve was decreased. Increased expression of synaptophysin in the dorsal root ganglion and dorsal spinal cord correlated with the intensity of injury. The amplitude of sensory evoked potential increased with greater severity of nerve damage. Mechanical allodynia and thermal hyperalgesia did not differ significantly among treatment groups at various time points. CatWalk XT gait analysis indicated significant differences for print areas, maximum contact maximum intensity, stand phase, swing phase, single stance, and regular index, with sham and/or intragroup comparisons. Conclusions. Histomorphological and electrophysiological alterations were associated with severity of nerve damage. Subtle neurobehavioral differences were detected by the CatWalk XT system but not by mechanical allodynia or thermal hyperalgesia. Thus, the CatWalk XT system should be a useful tool for monitoring changes in neuropathic pain, especially subtle alterations.

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Proteomic analysis of the dorsal spinal cord in the mouse model of spared nerve injury-induced neuropathic pain

Journal of Biomedical Research ◽

10.7555/jbr.31.20160122 ◽

2017 ◽

Vol 31 (6) ◽

pp. 494 ◽

Cited By ~ 1

Author(s):

Park Eun-sung ◽

Ahn Jung-mo ◽

Jeon Sang-min ◽

Cho Hee-jung ◽

Chung Ki-myung ◽

...

Keyword(s):

Spinal Cord ◽

Neuropathic Pain ◽

Mouse Model ◽

Nerve Injury ◽

Proteomic Analysis ◽

Spared Nerve Injury ◽

Dorsal Spinal Cord ◽

Dorsal Spinal

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Gabapentin and NMDA receptor antagonists interacts synergistically to alleviate allodynia in two rat models of neuropathic pain

Scandinavian Journal of Pain ◽

10.1515/sjpain-2018-0083 ◽

2018 ◽

Vol 18 (4) ◽

pp. 687-693 ◽

Cited By ~ 4

Author(s):

Tiansheng Shi ◽

Jing-Xia Hao ◽

Zsuzsanna Wiesenfeld-Hallin ◽

Xiao-Jun Xu

Keyword(s):

Spinal Cord ◽

Neuropathic Pain ◽

Nmda Receptor ◽

Side Effects ◽

Sciatic Nerve ◽

Nerve Injury ◽

Sciatic Nerve Injury ◽

Nmda Receptor Antagonists ◽

Receptor Antagonists ◽

Mk 801

Abstract Background and aims The clinical management of neuropathic pain remains a challenge. We examined the interaction between gabapentin and NMDA receptor antagonists dextromethrophan and MK-801 in alleviating neuropathic pain-like behaviors in rats after spinal cord or sciatic nerve injury. Methods Female and male rats were produced with Ischemic spinal cord injury and sciatic nerve injury. Gabapentin, dextromethorphan, MK-801 or drug combinations were injected with increasing doses. Mechanical response thresholds were tested with von Frey hairs to graded mechanical touch/pressure, and ethyl chloride spray was applied to assess the cold sensitivity before and after injuries. Results In spinally injured rats, gabapentin and dextromethorphan did not affect allodynia-like behaviors at doses of 30 and 20 mg/kg, respectively. In contrast, combination of 15 or 30 mg/kg gabapentin with dextromethorphan at 10 mg/kg produced total alleviation of allodynia to mechanical or cold stimulation. Further reducing the dose of gapapentin to 7.5 mg/kg and dextromethorphan to 5 mg/kg still produced significant effect. MK-801, another NMDA receptor antagonist, also enhanced the effect of gabapentin in spinally injured rats. Similar synergistic anti-allodynic effect between dextromethorphan and gabapentin was also observed in a rat model of partial sciatic nerve injury. No increased side effect was seen following the combination between gabapentin and dextromethorphan. Conclusions In conclusion, the present study suggested that combining NMDA receptor antagonists with gabapentin could provide synergistic effect to alleviate neuropathic pain and reduced side effects. Implications Combining NMDA receptor antagonists with gabapentin may provide a new approach in alleviating neuropathic pain with increased efficacy and reduced side effects.

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Resveratrol enhances IL-4 receptor-mediated anti-inflammatory effects in spinal cord and attenuates neuropathic pain following sciatic nerve injury

Molecular Pain ◽

10.1177/1744806918767549 ◽

2018 ◽

Vol 14 ◽

pp. 174480691876754 ◽

Cited By ~ 16

Author(s):

Mu Xu ◽

Zhigang Cheng ◽

Zhuofeng Ding ◽

Yunjiao Wang ◽

Qulian Guo ◽

...

Keyword(s):

Spinal Cord ◽

Neuropathic Pain ◽

Sciatic Nerve ◽

Nerve Injury ◽

Sciatic Nerve Injury ◽

Anti Inflammatory

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Spinal cord stimulation induces c-Fos expression in the dorsal horn in rats with neuropathic pain after partial sciatic nerve injury

Neuroscience Letters ◽

10.1016/j.neulet.2008.11.013 ◽

2009 ◽

Vol 450 (1) ◽

pp. 70-73 ◽

Cited By ~ 21

Author(s):

Helwin Smits ◽

Maarten V. Kleef ◽

Wiel Honig ◽

Job Gerver ◽

Philipp Gobrecht ◽

...

Keyword(s):

Spinal Cord ◽

Neuropathic Pain ◽

Sciatic Nerve ◽

Dorsal Horn ◽

Nerve Injury ◽

Spinal Cord Stimulation ◽

Sciatic Nerve Injury ◽

Fos Expression

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The effect of exercise frequency on neuropathic pain and pain-related cellular reactions in the spinal cord and midbrain in a rat sciatic nerve injury model

Journal of Pain Research ◽

10.2147/jpr.s156326 ◽

2018 ◽

Vol Volume 11 ◽

pp. 281-291 ◽

Cited By ~ 12

Author(s):

Megumi Sumizono ◽

Harutoshi Sakakima ◽

Shotaro Otsuka ◽

Takuto Terashi ◽

Kazuki Nakanishi ◽

...

Keyword(s):

Spinal Cord ◽

Neuropathic Pain ◽

Sciatic Nerve ◽

Nerve Injury ◽

Sciatic Nerve Injury ◽

Exercise Frequency ◽

Rat Sciatic Nerve ◽

Injury Model

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Micro- and Astroglia Activity in the Spinal Cord Ventrolateral Nucleus Sciatic Nerve Injury in Rats

Cell and Tissue Biology ◽

10.1134/s1990519x20040100 ◽

2020 ◽

Vol 14 (4) ◽

pp. 263-269

Author(s):

A. A. Starinets ◽

E. L. Egorova ◽

A. A. Tyrtyshnaia ◽

I. V. Dyuisen ◽

A. N. Baryshev ◽

...

Keyword(s):

Spinal Cord ◽

Sciatic Nerve ◽

Nerve Injury ◽

Sciatic Nerve Injury ◽

Ventrolateral Nucleus

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SUR1, newly expressed in astrocytes, mediates neuropathic pain in a mouse model of peripheral nerve injury

Molecular Pain ◽

10.1177/17448069211006603 ◽

2021 ◽

Vol 17 ◽

pp. 174480692110066

Author(s):

Orest Tsymbalyuk ◽

Volodymyr Gerzanich ◽

Aaida Mumtaz ◽

Sanketh Andhavarapu ◽

Svetlana Ivanova ◽

...

Keyword(s):

Spinal Cord ◽

Neuropathic Pain ◽

Sciatic Nerve ◽

Peripheral Nerve ◽

Dorsal Horn ◽

Nerve Injury ◽

Peripheral Nerve Injury ◽

Thermal Sensitivity ◽

Gradual Improvement ◽

Pain Behaviors

Background Neuropathic pain following peripheral nerve injury (PNI) is linked to neuroinflammation in the spinal cord marked by astrocyte activation and upregulation of interleukin 6 (IL -6 ), chemokine (C-C motif) ligand 2 (CCL2) and chemokine (C-X-C motif) ligand 1 (CXCL1), with inhibition of each individually being beneficial in pain models. Methods Wild type (WT) mice and mice with global or pGfap-cre- or pGFAP-cre/ERT2-driven Abcc8/SUR1 deletion or global Trpm4 deletion underwent unilateral sciatic nerve cuffing. WT mice received prophylactic (starting on post-operative day [pod]-0) or therapeutic (starting on pod-21) administration of the SUR1 antagonist, glibenclamide (10 µg IP) daily. We measured mechanical and thermal sensitivity using von Frey filaments and an automated Hargreaves method. Spinal cord tissues were evaluated for SUR1-TRPM4, IL-6, CCL2 and CXCL1. Results Sciatic nerve cuffing in WT mice resulted in pain behaviors (mechanical allodynia, thermal hyperalgesia) and newly upregulated SUR1-TRPM4 in dorsal horn astrocytes. Global and pGfap-cre-driven Abcc8 deletion and global Trpm4 deletion prevented development of pain behaviors. In mice with Abcc8 deletion regulated by pGFAP-cre/ERT2, after pain behaviors were established, delayed silencing of Abcc8 by tamoxifen resulted in gradual improvement over the next 14 days. After PNI, leakage of the blood-spinal barrier allowed entry of glibenclamide into the affected dorsal horn. Daily repeated administration of glibenclamide, both prophylactically and after allodynia was established, prevented or reduced allodynia. The salutary effects of glibenclamide on pain behaviors correlated with reduced expression of IL-6, CCL2 and CXCL1 by dorsal horn astrocytes. Conclusion SUR1-TRPM4 may represent a novel non-addicting target for neuropathic pain.

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