Gastrodia elata Blume Polysaccharides Attenuate Vincristine-Evoked Neuropathic Pain through the Inhibition of Neuroinflammation

Vincristine (Vin) is a well-known antitumor agent that frequently evokes neuropathic pain and decreases the quality of life of patients. Polysaccharides (GBP) extracted from Gastrodia elata Blume have been demonstrated to possess anti-inflammatory and neuroprotective effects in vivo; however, the effects of GBP on Vin-induced neuropathic pain remain unknown. The present study is aimed at exploring the alleviative potential of GBP against chemotherapy-evoked peripheral neuropathy to better understand and extend its pharmacological application. Vin was administered intraperitoneally to evoke neuropathic pain. GBP was orally administered for 21 days. The mechanical allodynia and thermal hyperalgesia were assessed using the Von Frey test and hot-plate test. Histopathological changes were assessed by hematoxylin and eosin staining. ELISA kits were used to measure the levels of inflammatory cytokines in the sciatic nerve, spinal cord, and dorsal root ganglion (DRG). qRT-PCR was employed to examine the expression of inflammatory cytokines and Sirtuin1 (SIRT1) in the sciatic nerve, spinal cord, and DRG. Our findings revealed that GBP treatment enhanced the paw withdrawal latency and paw withdrawal threshold and restored Vin-induced sciatic nerve damage in rats. GBP also attenuated the Vin-induced increase of proinflammatory cytokine levels, including IL-6, IL-8, TNF-α, IL-1β, and NF-κB. On the molecular level, treatment with GBP downregulated the mRNA levels of IL-6, IL-8, TNF-α, and IL-1β in the sciatic nerve, spinal cord, and DRG. Meanwhile, GBP increased SIRT1 activity and mRNA expression levels. Our data indicated that GBP exerted a potential protective effect against chemotherapy-induced neuropathic pain which might be mediated via the inhibition of neuroinflammation.

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Reciprocal Regulatory Interaction between TRPV1 and Kinin B1 Receptor in a Rat Neuropathic Pain Model

International Journal of Molecular Sciences ◽

10.3390/ijms21030821 ◽

2020 ◽

Vol 21 (3) ◽

pp. 821 ◽

Cited By ~ 1

Author(s):

Veronica Cernit ◽

Jacques Sénécal ◽

Rahmeh Othman ◽

Réjean Couture

Keyword(s):

Spinal Cord ◽

Neuropathic Pain ◽

Mrna Expression ◽

Thermal Hyperalgesia ◽

Mrna Levels ◽

Regulatory Interaction ◽

B1 Receptor ◽

Tnf Α ◽

Kinin B1 Receptor ◽

Sensory Fibers

Kinins are mediators of pain and inflammation and evidence suggests that the inducible kinin B1 receptor (B1R) is involved in neuropathic pain (NP). This study investigates whether B1R and TRPV1 are colocalized on nociceptors and/or astrocytes to enable regulatory interaction either directly or through the cytokine pathway (IL-1β, TNF-α) in NP. Sprague Dawley rats were subjected to unilateral partial sciatic nerve ligation (PSNL) and treated from 14 to 21 days post-PSNL with antagonists of B1R (SSR240612, 10 mg·kg−1, i.p.) or TRPV1 (SB366791, 1 mg·kg−1, i.p.). The impact of these treatments was assessed on nociceptive behavior and mRNA expression of B1R, TRPV1, TNF-α, and IL-1β. Localization on primary sensory fibers, astrocytes, and microglia was determined by immunofluorescence in the lumbar spinal cord and dorsal root ganglion (DRG). Both antagonists suppressed PSNL-induced thermal hyperalgesia, but only SB366791 blunted mechanical and cold allodynia. SSR240612 reversed PSNL-induced enhanced protein and mRNA expression of B1R and TRPV1 mRNA levels in spinal cord while SB366791 further increased B1R mRNA/protein expression. B1R and TRPV1 were found in non-peptide sensory fibers and astrocytes, and colocalized in the spinal dorsal horn and DRG, notably with IL-1β on astrocytes. IL-1β mRNA further increased under B1R or TRPV1 antagonism. Data suggest that B1R and TRPV1 contribute to thermal hyperalgesia and play a distinctive role in allodynia associated with NP. Close interaction and reciprocal regulatory mechanism are suggested between B1R and TRPV1 on astrocytes and nociceptors in NP.

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

Molecular Pain ◽

10.1177/1744806921996520 ◽

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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Dynamic effects of TNF-α on synaptic transmission in mice over time following sciatic nerve chronic constriction injury

Journal of Neurophysiology ◽

10.1152/jn.01088.2012 ◽

2013 ◽

Vol 110 (7) ◽

pp. 1663-1671 ◽

Cited By ~ 23

Author(s):

Hongmei Zhang ◽

Haijun Zhang ◽

Patrick M. Dougherty

Keyword(s):

Spinal Cord ◽

Neuropathic Pain ◽

Sciatic Nerve ◽

Synaptic Transmission ◽

Dorsal Horn ◽

Nerve Injury ◽

Chronic Constriction Injury ◽

Synaptic Signaling ◽

Tnf Α ◽

Over Time

Nerve injury-induced central sensitization can manifest as an increase in excitatory synaptic transmission and/or as a decrease in inhibitory synaptic transmission in spinal dorsal horn neurons. Cytokines such as tumor necrosis factor-α (TNF-α) are induced in the spinal cord under various injury conditions and contribute to neuropathic pain. In this study we examined the effect of TNF-α in modulating excitatory and inhibitory synaptic input to spinal substantia gelatinosa (SG) neurons over time in mice following chronic constriction injury (CCI) of the sciatic nerve. Whole cell patch-clamp studies from SG neurons showed that TNF-α enhanced overall excitability of the spinal cord early in time following nerve injury 3 days after CCI compared with that in sham control mice. In contrast, the effects of TNF were blunted 14 days after CCI in nerve-injured mice compared with sham surgery mice. Immunohistochemical staining showed that the expression of TNF-α receptor 1 (TNFR1) was increased at 3 days but decreased at 14 days following CCI in the ipsilateral vs. the contralateral spinal cord dorsal horn. These results suggest that TNF-α acting at TNFR1 is important in the development of neuropathic pain by facilitating excitatory synaptic signaling in the acute phases after nerve injury but has a reduced effect on spinal neuron signaling in the later phases of nerve injury-induced pain. Failure of the facilatory effects of TNF-α on excitatory synaptic signaling in the dorsal horn to resolve following nerve injury may be an important component in the transition between acute and chronic pain conditions.

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Protocatechuic acid as an inhibitor of the JNK/CXCL1/CXCR2 pathway relieves neuropathic pain in CCI rats

Bosnian Journal of Basic Medical Sciences ◽

10.17305/bjbms.2021.5928 ◽

2021 ◽

Author(s):

Hong-xia Chang ◽

Yue-feng Zhao

Keyword(s):

Neuropathic Pain ◽

Sciatic Nerve ◽

Satellite Cells ◽

Protocatechuic Acid ◽

Thermal Hyperalgesia ◽

Tnf Α ◽

Chemokine Ligand ◽

New Perspective

Emerging evidence has shown that protocatechuic acid (PCA) has antioxidant and anti-inflammatory effects. Evidence suggests that PCA can alleviate the injury of sciatic nerve, while the mechanism of its therapeutic effect on neuralgia remains unknown. Chromium bowel ligation was used in vivo to establish a chronic constriction injury (CCI) rat model to induce sciatic nerve pain. Subsequently, two doses of PCA were used to treat CCI rats. In vitro, 10 ng/mL TNF-α was used to stimulate glial satellite cells derived from the dorsal root ganglia (DRG) L4-L6 of the sciatic nerve to simulate sciatic nerve pain. PCA relieved mechanical allodynia and thermal hyperalgesia in CCI rats. CCK-8 assay revealed that PCA inhibited the proliferation of glial satellite cells induced by TNF-α. Moreover, ELISA demonstrated that PCA could improve the inflammatory response of rats caused by CCI and cells induced by TNF-α. Next, RT-qPCR and Western blot assays showed that PCA blocked the c-Jun N-terminal kinase/the chemokine ligand 1/CXC chemokine receptor 2 (JNK/CXCL1/CXCR2) pathway by inhibiting CXCL1 levels in cells induced by TNF-α and DRG in CCI rats. In conclusion, PCA can alleviate neuropathic pain in CCI rats and improve oxidative stress by inhibiting the JNK/CXCL1/CXCR2 signaling pathway. Thus, these findings provide a new perspective for the treatment of neuropathic pain caused by CCI.

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1,3,4-Oxadiazole Derivative Attenuates Chronic Constriction Injury Induced Neuropathic Pain: A Computational, Behavioral, and Molecular Approach

Brain Sciences ◽

10.3390/brainsci10100731 ◽

2020 ◽

Vol 10 (10) ◽

pp. 731

Author(s):

Muhammad Faheem ◽

Syed Hussain Ali ◽

Abdul Waheed Khan ◽

Mahboob Alam ◽

Umair Ilyas ◽

...

Keyword(s):

Spinal Cord ◽

Neuropathic Pain ◽

Sciatic Nerve ◽

Pain Perception ◽

Chronic Constriction Injury ◽

Neuroprotective Effect ◽

Underlying Mechanism ◽

Contributing Factors ◽

Neuroprotective Effects ◽

In Silico Studies

The production and up-regulation of inflammatory mediators are contributing factors for the development and maintenance of neuropathic pain. In the present study, the post-treatment of synthetic 1,3,4 oxadiazole derivative (B3) for its neuroprotective potential in chronic constriction injury-induced neuropathic pain was applied. In-silico studies were carried out through Auto Dock, PyRx, and DSV to obtain the possible binding and interactions of the ligands (B3) with COX-2, IL-6, and iNOS. The sciatic nerve of the anesthetized rat was constricted with sutures 3/0. Treatment with 1,3,4-oxadiazole derivative was started a day after surgery and continued until the 14th day. All behavioral studies were executed on day 0, 3rd, 7th, 10th, and 14th. The sciatic nerve and spinal cord were collected for further molecular analysis. The interactions in the form of hydrogen bonding stabilizes the ligand target complex. B3 showed three hydrogen bonds with IL-6. B3, in addition to correcting paw posture/deformation induced by CCI, attenuates hyperalgesia (p < 0.001) and allodynia (p < 0.001). B3 significantly raised the level of GST and GSH in both the sciatic nerve and spinal cord and reduced the LPO and iNOS (p < 0.001). B3 attenuates the pathological changes induced by nerve injury, which was confirmed by H&E staining and IHC examination. B3 down-regulates the over-expression of the inflammatory mediator IL-6 and hence provides neuroprotective effects in CCI-induced pain. The results demonstrate that B3 possess anti-nociceptive and anti-hyperalgesic effects and thus minimizes pain perception and inflammation. The possible underlying mechanism for the neuroprotective effect of B3 probably may be mediated through IL-6.

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SIRT1 Mediates Neuropathic Pain Induced by Sciatic Nerve Chronic Constrictive Injury in the VTA-NAc Pathway

Pain Research and Management ◽

10.1155/2020/4245968 ◽

2020 ◽

Vol 2020 ◽

pp. 1-9

Author(s):

Yangyang Li ◽

Lei Wang ◽

Guotao Zhang ◽

Xueli Qiao ◽

Mingxing Zhang

Keyword(s):

Spinal Cord ◽

Neuropathic Pain ◽

Sciatic Nerve ◽

Dorsal Root ◽

Elevated Level ◽

Thermal Hyperalgesia ◽

Sirtuin 1 ◽

Class Iii ◽

Histone 3 ◽

Chronic Constrictive Injury

Background. Mounting evidence has shown that sirtuin 1 (SIRT1), a class III histone deacetylase, alleviated several types of neuropathic pain in the spinal cord and dorsal root ganglion and regulated some aberrant behaviors in the ventral tegmental area (VTA) and the nucleus accumbens (NAc). Methods. In this context, the effect of SIRT1 on neuropathic pain in the VTA-NAc pathway was investigated in the model of chronic constrictive injury (CCI). Results. SIRT1 was localized in the VTA neurons in naive mice. The expression of SIRT1 was decreased in the contralateral VTA of CCI mice. After microinjection of SRT1720 (an activator of SIRT1) in the contralateral VTA of CCI mice, the established thermal hyperalgesia was attenuated. However, it was further exacerbated by EX-527 (an inhibitor of SIRT1). The elevated level of acetyl-histone 3 was reduced by SRT1720 but further elevated by EX-527 in the contralateral VTA of CCI mice. The increased expression of Fos in both VTA and NAc was downregulated by SRT1720 but further upregulated by EX-527 in CCI mice. Conclusions. The discovery of the effect of SIRT1 on neuropathic pain in the VTA represents an important step forward in understanding the analgesic mechanisms of the VTA-NAc pathway.

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Fumagillin Attenuates Spinal Angiogenesis, Neuroinflammation, and Pain in Neuropathic Rats After Chronic Constriction Injury

10.21203/rs.3.rs-741520/v1 ◽

2021 ◽

Author(s):

Zhi-Hong Wen ◽

Shi-Ying Huang ◽

Hsiao-Mei Kuo ◽

Chao-Ting Chen ◽

Nan-Fu Chen ◽

...

Keyword(s):

Spinal Cord ◽

Neuropathic Pain ◽

Chronic Constriction Injury ◽

Angiogenesis Inhibitor ◽

Thermal Hyperalgesia ◽

Lumbar Spinal Cord ◽

Astrocyte Activation ◽

Anti Vegf ◽

Tnf Α ◽

The Impact

Abstract Background Angiogenesis in the central nervous system is visible in animal models of neuroinflammation and bone cancer pain. However, whether spinal angiogenesis exists and contributes to central sensitization in neuropathic pain remains unclear. This study analyzed the impact of angiogenesis on spinal neuroinflammation in neuropathic pain. Methods Rats with chronic constriction injury (CCI) to sciatic nerve underwent implantation of an intrathecal catheter. Fumagillin or vascular endothelial growth factor-A antibody (anti-VEGF-A) was administered intrathecally. Nociceptive behaviors, cytokine immunoassay, Western blot, and immunohistochemical analysis assessed the effect of angiogenesis inhibition on CCI-induced neuropathic pain. Results VEGF, cluster of differentiation 31 (CD31), and von Willebrand factor (vWF) expressions increased after CCI in the ipsilateral lumbar spinal cord compared to that in the contralateral side of CCI and control rats from postoperative day (POD) 7 to 28, with a peak at POD 14. Tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and IL-6 concentrations, but not IL-10 levels, also increased in the ipsilateral spinal cord after CCI. Fumagillin and anti-VEGF-A reduced CCI-induced thermal hyperalgesia from POD 5 to 14 and mechanical allodynia from POD 3 to 14. Fumagillin reduced CCI-upregulated expressions of angiogenic factors and astrocytes. Furthermore, fumagillin decreased TNF-α and IL-6 amounts and increased IL-10 levels at POD 7 and 14, but not IL-1β concentrations. Conclusions Fumagillin significantly ameliorates CCI-induced nociceptive sensitization, spinal angiogenesis and astrocyte activation. Our results suggest that angiogenesis inhibitor treatment suppresses peripheral neuropathy-induced central angiogenesis, neuroinflammation, astrocyte activation, and neuropathic pain.

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Berberine reduces neuroglia activation and inflammation in streptozotocin-induced diabetic mice

International Journal of Immunopathology and Pharmacology ◽

10.1177/2058738419866379 ◽

2019 ◽

Vol 33 ◽

pp. 205873841986637 ◽

Cited By ~ 4

Author(s):

Mei Liu ◽

Linlin Gao ◽

Na Zhang

Keyword(s):

Neuropathic Pain ◽

Inflammatory Cytokines ◽

Thermal Hyperalgesia ◽

Enzyme Linked Immunosorbent Assay ◽

Diabetic Mice ◽

Mechanical Threshold ◽

Tnf Α ◽

Inflammatory Proteins ◽

Necrosis Factor ◽

Pro Inflammatory Cytokines

We aimed to analyze the action of berberine on the neuropathic pain and neuroglia activation in experimental diabetes mellitus (DM) model. Diabetes in mice was induced by intraperitoneal injection of streptozotocin (STZ) followed by the administration of berberine. Mechanical allodynia and thermal hyperalgesia and activations of microglia and astrocytes were evaluated. The levels of pro-inflammatory cytokines and protein expressions of inflammatory proteins were assessed by enzyme-linked immunosorbent assay (ELISA) and western blot, respectively. Our results revealed the anti-nociceptive effects of berberine in DM mice, supported by the improved mechanical threshold and thermal latency. In addition, berberine suppressed the activations of microglia and astrocytes in the spinal cords of diabetic mice. Berberine inhibited the expression of pro-inflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin-6 (IL-6), and interleukin-1β (IL-1β), along with inflammatory proteins including iNOS and COX-2. Berberine suppressed neuropathic pain in STZ-induced diabetic mice, and this effect is related to the reduction on the neuroglia activation and inflammation associated with DM.

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Effect of Umbelliprenin on antinociceptive activity of morphine in a rat model of neuropathic pain induced by chronic constriction injury of the sciatic nerve

The Natural Products Journal ◽

10.2174/2210315510999200421201705 ◽

2020 ◽

Vol 10 ◽

Author(s):

Samad Nazemi ◽

Faranak Jafari ◽

Bahareh Amin ◽

Omid Gholami ◽

Marzieh Kafami ◽

...

Keyword(s):

Spinal Cord ◽

Neuropathic Pain ◽

Sciatic Nerve ◽

Rat Model ◽

Chronic Constriction Injury ◽

Antinociceptive Activity ◽

Necrosis Factor Alpha ◽

Tnf Α ◽

Male Wistar Rats ◽

Anti Inflammatory

Objective: Although morphine is among of the first line medicines for treatment of neuropathic pain, evidence has shown that the morphine efficacy gradually decreases and a tolerance can occur. Rregarding the many reports concerning the antinociceptive and anti-inflammatory properties of umbelliprenin (UMB), this study aimed to investigate the effect of UMB on antinociceptive activity of morphine in a rat model of neuropathic pain induced by chronic constriction injury (CCI) of the sciatic nerve. Methods: Twenty-four male Wistar rats were randomly divided into sham, CCI and CCI + UMB100 (100 μg UMB per rat) groups. UMB was intrathecally administered once daily for four consecutive days (from the day before surgery until the day 2 after surgery). All the animals received a single dose of morphine (5 mg/kg, s.c.) on day 14. To evaluate the effect of UMB on antinociceptive activity of morphine, allodynia and hyperalgesia were measured using the von-Frey and hot plate tests, before and 30 min after morphine injection, and the Percentage of Maximum Possible Effect (%MPE) was calculated. In addition, the expression and concentration of tumor necrosis factor-alpha (TNF-α), as a proinflammatory cytokine, was measured in the spinal cord using quantitative real-time PCR (RT-PCR) and ELISA, respectively. Key Findings: UMB significantly enhanced anti-allodynic and anti-hyperalgesic effects of morphine in the neuropathic animals. Moreover, UMB considerably downregulated TNF-α expression in the spinal cord of the animals. Conclusion: UMB can enhance antinociceptive effects of morphine, and this action may be due in part to its anti-inflammatory property.

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Novel Mechanism for Memantine in Attenuating Diabetic Neuropathic Pain in Mice via Downregulating the Spinal HMGB1/TRL4/NF-kB Inflammatory Axis

Pharmaceuticals ◽

10.3390/ph14040307 ◽

2021 ◽

Vol 14 (4) ◽

pp. 307

Author(s):

Suliman Y. Alomar ◽

Rehab E. Abo El Gheit ◽

Eman T. Enan ◽

Khaled S. El-Bayoumi ◽

Mohamed Z. Shoaeir ◽

...

Keyword(s):

Spinal Cord ◽

Neuropathic Pain ◽

Neuroprotective Effect ◽

Interleukin 1 ◽

Thermal Hyperalgesia ◽

High Mobility ◽

Enzyme Linked Immunosorbent Assay ◽

Diabetic Mice ◽

Diabetic Neuropathic Pain ◽

Neuroprotective Effects

Diabetic neuropathic pain (DNP) is a common diabetic complication that currently lacks an efficient therapy. The aim of the current work was to uncover the anti-allodynic and neuroprotective effects of memantine in a model of mouse diabetic neuropathy and its ameliorative effect on the high-mobility group box-1 (HMGB1)/toll-like receptor 4 (TLR4)/nuclear factor-k B (NF-kB) inflammatory axis. Diabetes was prompted by an alloxan injection (180 mg/kg) to albino mice. On the ninth week after diabetes induction, DNP was confirmed. Diabetic mice were randomly allocated to two groups (six mice each); a diabetes mellitus (DM) group and DM+memantine group (10 mg/kg, daily) for five weeks. DNP-related behaviors were assessed in terms of thermal hyperalgesia and mechanical allodynia by hot-plate and von Frey filaments. Enzyme-linked immunosorbent assay (ELISA) kits were used to measure the spinal glutamate, interleukin-1 beta (IL-1β), and tumor necrosis factor-α (TNF-α). The spinal levels of N-methyl-D-aspartate type 1 receptor (NMDAR1), HMGB1, TLR4, and phosphorylated NF-kB were assessed using Western blotting. Histopathological investigation of the spinal cord and sciatic nerves, together with the spinal cord ultrastructure, was employed for assessment of the neuroprotective effect. Memantine alleviated pain indicators in diabetic mice and suppressed excessive NMDAR1 activation, glutamate, and pro-inflammatory cytokine release in the spinal cord. The current study validated the ability of memantine to combat the HMGB1/TLR4/NF-kB axis and modulate overactive glutamate spinal transmission, corroborating memantine as an appealing therapeutic target in DNP.

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