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Scarneo S, Zhang X, Wang Y, Camacho-Domenech J, Ricano J, Hughes P, Haystead T, Nackley AG. Transforming Growth Factor-β-Activated Kinase 1 (TAK1) Mediates Chronic Pain and Cytokine Production in Mouse Models of Inflammatory, Neuropathic, and Primary Pain. THE JOURNAL OF PAIN 2023; 24:1633-1644. [PMID: 37121498 PMCID: PMC10524186 DOI: 10.1016/j.jpain.2023.04.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 04/07/2023] [Accepted: 04/24/2023] [Indexed: 05/02/2023]
Abstract
The origin of chronic pain is linked to inflammation, characterized by increased levels of proinflammatory cytokines in local tissues and systemic circulation. Transforming growth factor beta-activated kinase 1 (TAK1) is a key regulator of proinflammatory cytokine signaling that has been well characterized in the context of cancer and autoimmune disorders, yet its role in chronic pain is less clear. Here, we evaluated the ability of our TAK1 small-molecule inhibitor, takinib, to attenuate pain and inflammation in preclinical models of inflammatory, neuropathic, and primary pain. Inflammatory, neuropathic, and primary pain was modeled using intraplantar complete Freund's adjuvant (CFA), chronic constriction injury (CCI), and systemic delivery of the catechol-O-methyltransferase (COMT) inhibitor OR486, respectively. Behavioral responses evoked by mechanical and thermal stimuli were evaluated in separate groups of mice receiving takinib or vehicle prior to pain induction (baseline) and over 12 days following CFA injection, 4 weeks following CCI surgery, and 6 hours following OR486 delivery. Hindpaw edema was also measured prior to and 3 days following CFA injection. Upon termination of behavioral experiments, dorsal root ganglia (DRG) were collected to measure cytokines. We also evaluated the ability of takinib to modulate nociceptor activity via in vitro calcium imaging of neurons isolated from the DRG of Gcamp3 mice. In all 3 models, TAK1 inhibition significantly reduced hypersensitivity to mechanical and thermal stimuli and expression of proinflammatory cytokines in DRG. Furthermore, TAK1 inhibition significantly reduced the activity of tumor necrosis factor (TNF)-primed/capsaicin-evoked DRG nociceptive neurons. Overall, our results support the therapeutic potential of TAK1 as a novel drug target for the treatment of chronic pain syndromes with different etiologies. PERSPECTIVE: This article reports the therapeutic potential of TAK1 inhibitors for the treatment of chronic pain. This new treatment has the potential to provide a greater therapeutic offering to physicians and patients suffering from chronic pain as well as reduce the dependency on opioid-based pain treatments.
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Affiliation(s)
- Scott Scarneo
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina; Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina; EydisBio Inc., Department of Research and Development Durham, North Carolina.
| | - Xin Zhang
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina; Department of Anesthesiology, Nanjing Medical University Affiliated Wuxi People's Hospital, Wuxi, Jiangsu, China
| | - Yaomin Wang
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina
| | - Jose Camacho-Domenech
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina; Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina
| | - Jennifer Ricano
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina
| | - Philip Hughes
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina; EydisBio Inc., Department of Research and Development Durham, North Carolina
| | - Tim Haystead
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina; EydisBio Inc., Department of Research and Development Durham, North Carolina
| | - Andrea G Nackley
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina; Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina
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McGinnis A, Ji RR. The Similar and Distinct Roles of Satellite Glial Cells and Spinal Astrocytes in Neuropathic Pain. Cells 2023; 12:965. [PMID: 36980304 PMCID: PMC10047571 DOI: 10.3390/cells12060965] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 03/19/2023] [Accepted: 03/20/2023] [Indexed: 03/30/2023] Open
Abstract
Preclinical studies have identified glial cells as pivotal players in the genesis and maintenance of neuropathic pain after nerve injury associated with diabetes, chemotherapy, major surgeries, and virus infections. Satellite glial cells (SGCs) in the dorsal root and trigeminal ganglia of the peripheral nervous system (PNS) and astrocytes in the central nervous system (CNS) express similar molecular markers and are protective under physiological conditions. They also serve similar functions in the genesis and maintenance of neuropathic pain, downregulating some of their homeostatic functions and driving pro-inflammatory neuro-glial interactions in the PNS and CNS, i.e., "gliopathy". However, the role of SGCs in neuropathic pain is not simply as "peripheral astrocytes". We delineate how these peripheral and central glia participate in neuropathic pain by producing different mediators, engaging different parts of neurons, and becoming active at different stages following nerve injury. Finally, we highlight the recent findings that SGCs are enriched with proteins related to fatty acid metabolism and signaling such as Apo-E, FABP7, and LPAR1. Targeting SGCs and astrocytes may lead to novel therapeutics for the treatment of neuropathic pain.
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Affiliation(s)
- Aidan McGinnis
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Ru-Rong Ji
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA
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Chen YL, Feng XL, Cheung CW, Liu JA. Mode of action of astrocytes in pain: From the spinal cord to the brain. Prog Neurobiol 2022; 219:102365. [DOI: 10.1016/j.pneurobio.2022.102365] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 09/09/2022] [Accepted: 10/07/2022] [Indexed: 11/06/2022]
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Astrocytes in Chronic Pain: Cellular and Molecular Mechanisms. Neurosci Bull 2022; 39:425-439. [PMID: 36376699 PMCID: PMC10043112 DOI: 10.1007/s12264-022-00961-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 06/17/2022] [Indexed: 11/15/2022] Open
Abstract
AbstractChronic pain is challenging to treat due to the limited therapeutic options and adverse side-effects of therapies. Astrocytes are the most abundant glial cells in the central nervous system and play important roles in different pathological conditions, including chronic pain. Astrocytes regulate nociceptive synaptic transmission and network function via neuron–glia and glia–glia interactions to exaggerate pain signals under chronic pain conditions. It is also becoming clear that astrocytes play active roles in brain regions important for the emotional and memory-related aspects of chronic pain. Therefore, this review presents our current understanding of the roles of astrocytes in chronic pain, how they regulate nociceptive responses, and their cellular and molecular mechanisms of action.
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Sun X, Li X, Zhou Y, Wang Y, Liu X. Exogenous TIPE2 Inhibit TAK1 to Improve Inflammation and Neuropathic Pain Induced by Sciatic Nerve Injury Through Inactivating NF-κB and JNK. Neurochem Res 2022; 47:3167-3177. [PMID: 35842555 PMCID: PMC9470725 DOI: 10.1007/s11064-022-03671-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 06/15/2022] [Accepted: 06/23/2022] [Indexed: 11/28/2022]
Abstract
Tumor necrosis factor-alpha-induced protein 8-like 2 (TIPE2) possesses potent anti-inflammatory effect. However, if TIPE2 ameliorates sciatic nerve injury (SNI)-induced inflammation and pain remains undiscussed, and the underlying role TAK1 in it were unknown. To verify our imagine, we performed SNI surgery, and analyzed expression and colocalization of TIPE2 and TAK1 in spinal cord and dorsal root neurons (DRG) by immunofluorescence staining and western blot. And the biological analysis, inflammatory factors, and pathological improvement were determined, and the regulation of TIPE2 in TAK1, phosphor-NF-κB, phospho-JNK was also tested by immunofluorescence staining and western blot. Experimental results showed the parabola-like change of TIPE2 and rising expression of TAK1 in spinal cord and DRG. And intrathecal TIPE2 injection could significantly improve the status of SNI rats, inhibit level of IL-6, IL-10 and TNF-α, raise the thermal withdrawal relax latency and mechanical withdrawal thresholds. Meanwhile, we also detected how TIPE2 regulated TAK1, and the downstream pathway NF-κB and JNK. The result indicated that TIPE2 could reduce TAK1 expression, and make NF-κB and JNK inactivated. To deeply discuss the potential mechanism, we injected TAK1 oligodeoxynucleotide into rats, and found that TIPE2 exerted the protective role against SNI through TAK1. In brief, TIPE2 reduced expression of TAK1, thereby inhibiting activation of NF-kB and JNK, further improving the neuroinflammation and neuropathic pain. TIPE2 played a protective role in sciatic nerve injury rats through regulating TAK1.
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Affiliation(s)
- Xuehua Sun
- Pain department, Yantai Affiliated Hospital of Binzhou Medical University, No. 717, Jinbu street, Muping District, Yantai City, 264100, Shandong, People's Republic of China.
| | - Xinyou Li
- Pain department, Yantai Affiliated Hospital of Binzhou Medical University, No. 717, Jinbu street, Muping District, Yantai City, 264100, Shandong, People's Republic of China
| | - Youfei Zhou
- Pain department, Yantai Affiliated Hospital of Binzhou Medical University, No. 717, Jinbu street, Muping District, Yantai City, 264100, Shandong, People's Republic of China
| | - Yufei Wang
- Pain department, Yantai Affiliated Hospital of Binzhou Medical University, No. 717, Jinbu street, Muping District, Yantai City, 264100, Shandong, People's Republic of China
| | - Xiaochen Liu
- Pain department, Yantai Affiliated Hospital of Binzhou Medical University, No. 717, Jinbu street, Muping District, Yantai City, 264100, Shandong, People's Republic of China
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The Role of ATP Receptors in Pain Signaling. Neurochem Res 2022; 47:2454-2468. [DOI: 10.1007/s11064-021-03516-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/11/2021] [Accepted: 12/22/2021] [Indexed: 12/21/2022]
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Wang H, Huang M, Wang W, Zhang Y, Ma X, Luo L, Xu X, Xu L, Shi H, Xu Y, Wang A, Xu T. Microglial TLR4-induced TAK1 phosphorylation and NLRP3 activation mediates neuroinflammation and contributes to chronic morphine-induced antinociceptive tolerance. Pharmacol Res 2021; 165:105482. [PMID: 33549727 DOI: 10.1016/j.phrs.2021.105482] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 02/02/2021] [Accepted: 02/02/2021] [Indexed: 01/04/2023]
Abstract
BACKGROUND AND PURPOSE The aim of this work was to investigate the role and signal transduction of toll-like receptor 4 (TLR4), TGF-β-activated kinase 1 (TAK1) and nod-like receptor protein 3 (NLRP3) in microglial in the development of morphine-induced antinociceptive tolerance. METHODS TLR4 and NLRP3 knockout mice and 5Z-7-oxozeaeno (a selective inhibitor against TAK1 activity) were used to observe their effect on the development of morphine tolerance. Intrathecal injections of morphine (0.75 mg/kg once daily for 7 days) were used to establish anti-nociceptive tolerance, which was measured by the tail-flick test. Spinal TLR4, TAK1, and NLRP3 expression levels and phosphorylation of TAK1 were evaluated by Western blotting and immunofluorescence. RESULTS Repeated treatment with morphine increased total expression of spinal TLR4, TAK1, and NLRP3 and phosphorylation of TAK1 in wild-type mice. TLR4 knockout attenuated morphine-induced tolerance and inhibited the chronic morphine-induced increase in NLRP3 and phosphorylation of TAK1. Compared with controls, mice that received 5Z-7-oxozeaenol showed decreased development of morphine tolerance and inhibition on repeated morphine-induced increase of NLRP3 but not TLR4. NLRP3 knockout mice showed resistance to morphine-induced analgesic tolerance with no effect on chronic morphine-induced expression of TLR4 and TAK1. TLR4, TAK1, and NLRP3 were collectively co-localized together and with the microglia marker Iba1. CONCLUSIONS Microglial TLR4 regulates TAK1 expression and phosphorylation and results in NLRP3 activation contributes to the development of morphine tolerance through regulating neuroinflammation. Targeting TLR4-TAK1-NLRP3 signaling to regulate neuro-inflammation will be alternative therapeutics and strategies for chronic morphine-induced antinociceptive tolerance.
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Affiliation(s)
- Haiyan Wang
- Department of Anesthesiology, Tongzhou People's Hospital, Nantong 226300, China; Department of Anesthesiology and Pain Clinic, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yi Shan Road, Shanghai 200233, China
| | - Min Huang
- Department of Anesthesiology and Pain Clinic, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yi Shan Road, Shanghai 200233, China
| | - Wenying Wang
- Department of Anesthesiology and Pain Clinic, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yi Shan Road, Shanghai 200233, China
| | - Yu Zhang
- Department of Anesthesiology and Pain Clinic, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yi Shan Road, Shanghai 200233, China
| | - Xiaqing Ma
- Department of Anesthesiology and Pain Clinic, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yi Shan Road, Shanghai 200233, China
| | - Limin Luo
- Department of Anesthesiology and Pain Clinic, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yi Shan Road, Shanghai 200233, China
| | - Xiaotao Xu
- Department of Anesthesiology and Pain Clinic, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yi Shan Road, Shanghai 200233, China
| | - Liang Xu
- Heart Health Center, East Hospital, Tongji University School of Medicine, Shanghai 200120, China
| | - Haibo Shi
- Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai 200233, China
| | - Yongming Xu
- Department of Anesthesiology and Pain Clinic, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yi Shan Road, Shanghai 200233, China.
| | - Aizhong Wang
- Department of Anesthesiology and Pain Clinic, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yi Shan Road, Shanghai 200233, China.
| | - Tao Xu
- Department of Anesthesiology, Tongzhou People's Hospital, Nantong 226300, China; Department of Anesthesiology and Pain Clinic, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yi Shan Road, Shanghai 200233, China.
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Totzke J, Scarneo SA, Yang KW, Haystead TAJ. TAK1: a potent tumour necrosis factor inhibitor for the treatment of inflammatory diseases. Open Biol 2020; 10:200099. [PMID: 32873150 PMCID: PMC7536066 DOI: 10.1098/rsob.200099] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Aberrant tumour necrosis factor (TNF) signalling is a hallmark of many inflammatory diseases including rheumatoid arthritis (RA), irritable bowel disease and lupus. Maladaptive TNF signalling can lead to hyper active downstream nuclear factor (NF)-κβ signalling in turn amplifying a cell's inflammatory response and exacerbating disease. Within the TNF intracellular inflammatory signalling cascade, transforming growth factor-β-activated kinase 1 (TAK1) has been shown to play a critical role in mediating signal transduction and downstream NF-κβ activation. Owing to its role in TNF inflammatory signalling, TAK1 has become a potential therapeutic target for the treatment of inflammatory diseases such as RA. This review highlights the current development of targeting the TNF-TAK1 signalling axis as a novel therapeutic strategy for the treatment of inflammatory diseases.
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Affiliation(s)
- Juliane Totzke
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Scott A Scarneo
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Kelly W Yang
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Timothy A J Haystead
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
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Huang CT, Chen SH, Chang CF, Lin SC, Lue JH, Tsai YJ. Melatonin reduces neuropathic pain behavior and glial activation through MT 2 melatonin receptor modulation in a rat model of lysophosphatidylcholine-induced demyelination neuropathy. Neurochem Int 2020; 140:104827. [PMID: 32853748 DOI: 10.1016/j.neuint.2020.104827] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 07/28/2020] [Accepted: 08/07/2020] [Indexed: 12/17/2022]
Abstract
In this study, we investigated whether melatonin treatment prevents development of neuropathic pain via suppression of glial mitogen-activated protein kinases (MAPKs) activation in the cuneate nucleus (CN) in a lysophosphatidylcholine (LPC)-induced median nerve demyelination neuropathy model. Rats were fed orally with melatonin once a day at a dose of 37.5, 75, or 150 mg/kg 30 min before until 3 days after LPC treatment. Subsequently, behavioral tests were conducted on these animals, and immunohistochemistry and immunoblotting were used for qualitative and quantitative analysis of glia and MAPKs, including ERK, JNK, and p38, activation. Enzyme-linked immunosorbent assays were applied to measure pro-inflammatory cytokine responses. Furthermore, intra-CN microinjection of S26131 (MT1 receptor antagonist), 4P-PDOT (MT2 receptor antagonist), or prazosin (MT3 receptor antagonist) were performed to investigate the association between melatonin receptor subtypes and effects of melatonin on demyelination neuropathy. LPC treatment of the median nerve induced a significant increase in glial fibrillary acidic protein (GFAP; an astrocyte marker) and ED1 (an activated microglia marker) immunoreactivity in the ipsilateral CN and led to development of neuropathic pain behavior. Inspection of GFAP-immunoreactive astrocytes revealed that astrocytic hypertrophy, but not proliferation, contributed to increased GFAP immunoreactivity. Double immunofluorescence showed that both GFAP-immunoreactive astrocytes and ED1-immunoreactive microglia co-expressed p-ERK, p-JNK, and p-p38 immunoreactivity. Melatonin administration dose-dependently reduced neuropathic pain behavior, decreased glial and MAPKs activation, and diminished the release of pro-inflammatory cytokines in the ipsilateral CN after LPC treatment. Furthermore, 4P-PDOT, but not S26131 or prazosin, antagonized the therapeutic effects of melatonin. In conclusion, administration of melatonin, via its cognate MT2 receptor, inhibited activation of glial MAPKs, production of pro-inflammatory cytokines, and development of demyelination-induced neuropathic pain behavior.
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Affiliation(s)
- Chun-Ta Huang
- Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Seu-Hwa Chen
- Department of Anatomy, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Chi-Fen Chang
- Department of Anatomy, School of Medicine, China Medical University, Taichung, Taiwan
| | - Shih-Chang Lin
- Division of Allergy and Immunology, Department of Internal Medicine, Cathay General Hospital, Taipei, Taiwan
| | - June-Horng Lue
- Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Yi-Ju Tsai
- Graduate Institute of Biomedical and Pharmaceutical Science, College of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan.
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Mai L, Zhu X, Huang F, He H, Fan W. p38 mitogen-activated protein kinase and pain. Life Sci 2020; 256:117885. [PMID: 32485175 DOI: 10.1016/j.lfs.2020.117885] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 05/23/2020] [Accepted: 05/28/2020] [Indexed: 12/18/2022]
Abstract
Inflammatory and neuropathic pain is initiated by tissue inflammation and nerve injury, respectively. Both are characterized by increased activity in the peripheral and central nervous system, where multiple inflammatory cytokines and other active molecules activate different signaling pathways that involve in the development and/or maintenance of pain. P38 mitogen-activated protein kinase (MAPK) is one member of the MAPK family, which is activated in neurons and glia and contributes importantly to inflammatory and neuropathic pain. The aim of this review is to summarize the latest advances made about the implication of p38 MAPK signaling cascade in pain. It can deepen our understanding of the molecular mechanisms of pain and may help to offer new targets for pain treatment.
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Affiliation(s)
- Lijia Mai
- Department of Anesthesiology, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou 510080, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510080, China
| | - Xiao Zhu
- The Marine Biomedical Research Institute, Guangdong Medical University, Zhanjiang 524023, China
| | - Fang Huang
- Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510080, China
| | - Hongwen He
- Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510080, China
| | - Wenguo Fan
- Department of Anesthesiology, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou 510080, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510080, China.
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Dai WL, Yan B, Bao YN, Fan JF, Liu JH. Suppression of peripheral NGF attenuates neuropathic pain induced by chronic constriction injury through the TAK1-MAPK/NF-κB signaling pathways. Cell Commun Signal 2020; 18:66. [PMID: 32312253 PMCID: PMC7171864 DOI: 10.1186/s12964-020-00556-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 03/17/2020] [Indexed: 11/27/2022] Open
Abstract
Background Anti-nerve growth factor (NGF) monoclonal antibodies (anti-NGF mAbs) have been reported to significantly attenuate pain, but the mechanism involved has not been fully elucidated, and the serious adverse events associated with mAbs seriously limit their clinical use. This study further investigated the mechanism by which peripheral NGF is involved in neuropathic pain and found safe, natural compounds that target NGF to attenuate neuropathic pain. Methods Nociception was assessed by the Von Frey hair and Hargreaves’ methods. Western-blotting, qPCR and immunofluorescence were used to detect the cell signaling pathway. RAW264.7 macrophages and RSC96 Schwann cells were cultured for in vitro evaluation. Results Intraplantar administration of anti-NGF mAbs suppressed the expression of phosphorylated transforming growth factor-β-activated kinase 1 (TAK1) in the dorsal root ganglion (DRG) and sciatic nerve. Intraplantar administration of a TAK1 inhibitor attenuated CCI-induced neuropathic pain and suppressed the expression of phosphorylated mitogen-activated protein kinases (MAPKs) in the DRG and sciatic nerve. Perisciatic nerve administration of levo-corydalmine (l-CDL) on the operated side obviously attenuated CCI-induced neuropathic pain and suppressed the expression of mNGF and proNGF. In addition, l-CDL-induced antinociception was reversed by intraplantar administration of NGF. Further results indicated that l-CDL-induced suppression of phosphorylated TAK1, MAPKs, and p65 and expression of the proinflammatory cytokines TNF-α and IL-1β in the DRG and sciatic nerve were all abolished by NGF. In addition, in vitro experiments indicated that l-CDL suppressed the secretion of NGF and proNGF in RAW264.7 macrophages and RSC96 Schwann cells, which was abolished by AP-1 and CREB agonists, respectively. Conclusions This study showed NGF inhibition suppressed TAK1 in the periphery to attenuate CCI-induced neuropathic pain through inhibition of downstream MAPK and p65 signaling. The natural compound l-CDL inhibited NGF secretion by macrophages and Schwann cells and downstream TAK1-MAPK/NF-κB signaling in the periphery to attenuate CCI-induced neuropathic pain. Video abstract
Graphical abstract Proposed mechanisms underlying the effect of l-CDL in periphery of CCI rats. In CCI rats, macropahages and Schwann cells could secret NGF to act on the receptors in the periphery to activate TAK1-MAPK/NF-κB axis and promote the release of proinflammatory cytokines, including TNF-α and IL-1β to promote neuropathic pain. l-CDL decreased the secretion of NGF through inhibiting AP-1 and CREB respectively in RAW264.7 and RSC96 Schwann cells to attenuate CCI-induced neuropathic pain by inhibiting the TAK1-p38 MAPK/NF-κB signaling pathway.
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Affiliation(s)
- Wen-Ling Dai
- Jiangsu Key Laboratory of TCM Evaluation and Translational Research, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 211198, Jiangsu, China
| | - Bing Yan
- Jiangsu Key Laboratory of TCM Evaluation and Translational Research, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 211198, Jiangsu, China
| | - Yi-Ni Bao
- Jiangsu Key Laboratory of TCM Evaluation and Translational Research, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 211198, Jiangsu, China
| | - Ji-Fa Fan
- Jiangsu Key Laboratory of TCM Evaluation and Translational Research, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 211198, Jiangsu, China
| | - Ji-Hua Liu
- Jiangsu Key Laboratory of TCM Evaluation and Translational Research, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 211198, Jiangsu, China. .,State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, Jiangsu, China.
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Zhang YY, Song N, Liu F, Lin J, Liu MK, Huang CL, Liao DQ, Zhou C, Wang H, Shen JF. Activation of the RAS/B-RAF-MEK-ERK pathway in satellite glial cells contributes to substance p-mediated orofacial pain. Eur J Neurosci 2019; 51:2205-2218. [PMID: 31705725 DOI: 10.1111/ejn.14619] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Revised: 10/11/2019] [Accepted: 11/01/2019] [Indexed: 02/06/2023]
Abstract
The cross talk between trigeminal ganglion (TG) neurons and satellite glial cells (SGCs) is crucial for the regulation of inflammatory orofacial pain. Substance P (SP) plays an important role by activating neurokinin (NK)-I receptors in this cross talk. The activation of extracellular signal-regulated kinase (ERK) 1/2, protein kinase A (PKA) and protein kinase C (PKC) in neurons and SGCs of peripheral ganglions by peripheral inflammation is associated with inflammatory hypersensitivity. This study tested the hypothesis that SP evoked SP-NK-I receptor positive feedback via the Renin-Angiotensin System/B-Protein Kinase A-Rapidly Accelerates Fibrosarcoma-MEK-Extracellular Signal-Regulated Kinase (RAS/PKA-RAF-MEK-ERK) pathway, which is involved in pain hypersensitivity. Inflammatory models were induced in vivo by injecting Complete Freund's adjuvant (CFA) into the whisker pad of rats. SP was administrated to SGCs in vitro for investigating, whether SP regulates the expression of NK-I receptor in the SGC nucleus. The effects of RAS-RAF-MEK, PKA and PKC pathways in this process were measured by co-incubating SGCs with respective Raf, PKA, PKC and MEK inhibitors in vitro and by pre-injecting these inhibitors into the TG in vivo. SP significantly upregulated NK-I receptor, p-ERK1/2, Ras, B-Raf, PKA and PKC in SGCs under inflammatory conditions. In addition, L703,606 (NK-I receptor antagonist), U0126 (MEK inhibitor), Sorafenib (Raf inhibitor) and H892HCL (PKA inhibitor) but not chelerythrine chloride (PKC inhibitor) significantly decreased NK-I mRNA and protein levels induced by SP. The allodynia-related behavior evoked by CFA was inhibited by pre-injection of L703,606, U0126, Sorafenib and H892HCL into the TG. Overall, SP upregulates NK-I receptor in TG SGCs via PKA/RAS-RAF-MEK-ERK pathway activation, contributing to a positive feedback of SP-NK-I receptor in inflammatory orofacial pain.
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Affiliation(s)
- Yan-Yan Zhang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Ning Song
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Fei Liu
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jiu Lin
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Meng-Ke Liu
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Chao-Lan Huang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Da-Qing Liao
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital of Sichuan University, Chengdu, China
| | - Cheng Zhou
- Laboratory of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital of Sichuan University, Chengdu, China
| | - Hang Wang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jie-Fei Shen
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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Abstract
Astrocytes are critical for maintaining the homeostasis of the CNS. Increasing evidence suggests that a number of neurological and neuropsychiatric disorders, including chronic pain, may result from astrocyte 'gliopathy'. Indeed, in recent years there has been substantial progress in our understanding of how astrocytes can regulate nociceptive synaptic transmission via neuronal-glial and glial-glial cell interactions, as well as the involvement of spinal and supraspinal astrocytes in the modulation of pain signalling and the maintenance of neuropathic pain. A role of astrocytes in the pathogenesis of chronic itch is also emerging. These developments suggest that targeting the specific pathways that are responsible for astrogliopathy may represent a novel approach to develop therapies for chronic pain and chronic itch.
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Li Q, Liu S, Li L, Ji X, Wang M, Zhou J. Spinal IL-36γ/IL-36R participates in the maintenance of chronic inflammatory pain through astroglial JNK pathway. Glia 2018; 67:438-451. [PMID: 30578562 DOI: 10.1002/glia.23552] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 09/22/2018] [Accepted: 10/01/2018] [Indexed: 12/18/2022]
Abstract
Emerging evidence indicates that spinal neuroinflammation contributes to the maintenance of chronic inflammatory pain. IL-36, as a novel member of the interleukin (IL)-1 super-family cytokines, plays an important role in inflammatory responses. The present study aimed to investigate the role of spinal IL-36 and IL-36 receptor (IL-36R) signaling in the pathology of chronic inflammatory pain. IL-36γ and IL-36R, but not IL-36α and IL-36β, were persistently upregulated in the spinal cord of mice with intraplantar injections of complete Freund's adjuvant (CFA). Intrathecal administration of both IL-36R antagonist (IL-36Ra) and IL-36γ siRNA significantly attenuated CFA-induced chronic inflammatory pain behaviors. Furthermore, CFA-induced IL-36γ expression was mainly observed in spinal neurons whereas IL-36R was primarily expressed in spinal astrocytes. Additionally, the intrathecal injection of IL-36γ was sufficient to induce pain hypersensitivity and astrocyte activation in naive mice, and these effects could be inhibited by blocking c-Jun N-terminal kinase (JNK) phosphorylation. In vitro experiments also demonstrated that the IL-36γ could induce astrocytic JNK activation and inflammatory cytokines release, which was mediated by IL-36R. Finally, intrathecal injection of IL-36γ-activated astrocytes in a pJNK-dependent manner induced mechanical allodynia and thermal hyperalgesia in naive mice. Collectively, these findings reveal that the neuronal/astrocytic interaction in the spinal cord by which neuronally produced IL-36γ activates astrocytes via IL-36R-mediated JNK pathway is crucial for the maintenance of chronic inflammatory pain. Thus, IL-36γ/IL-36R-mediated astrocyte signaling may be a suitable therapeutic target for chronic inflammatory pain.
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Affiliation(s)
- Qian Li
- Department of Central Laboratory, Shanghai Children's Hospital, Shanghai Jiaotong University, Shanghai, China
| | - Shenbin Liu
- Department of Integrative Medicine and Neurobiology, State Key Laboratory of Medical Neurobiology, School of Basic Medical Science, Institutes of Brain Science, Collaborative Innovation Center for Brain Science, Fudan Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Lingling Li
- Department of Central Laboratory, Shanghai Children's Hospital, Shanghai Jiaotong University, Shanghai, China
| | - Xiaoli Ji
- Department of Central Laboratory, Shanghai Children's Hospital, Shanghai Jiaotong University, Shanghai, China
| | - Min Wang
- Department of Central Laboratory, Shanghai Children's Hospital, Shanghai Jiaotong University, Shanghai, China
| | - Junmei Zhou
- Department of Central Laboratory, Shanghai Children's Hospital, Shanghai Jiaotong University, Shanghai, China
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Deep sequencing and miRNA profiles in alcohol-induced neuroinflammation and the TLR4 response in mice cerebral cortex. Sci Rep 2018; 8:15913. [PMID: 30374194 PMCID: PMC6206094 DOI: 10.1038/s41598-018-34277-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 10/10/2018] [Indexed: 12/12/2022] Open
Abstract
Alcohol abuse can induce brain injury and neurodegeneration, and recent evidence shows the participation of immune receptors toll-like in the neuroinflammation and brain damage. We evaluated the role of miRNAs as potential modulators of the neuroinflammation associated with alcohol abuse and the influence of the TLR4 response. Using mice cerebral cortex and next-generation sequencing (NGS), we identified miRNAs that were differentially expressed in the chronic alcohol-treated versus untreated WT or TLR4-KO mice. We observed a differentially expression of miR-183 Cluster (C) (miR-96/-182/-183), miR-200a and miR-200b, which were down-regulated, while mirR-125b was up-regulated in alcohol-treated WT versus (vs.) untreated mice. These miRNAs modulate targets genes related to the voltage-gated sodium channel, neuron hyperexcitability (Nav1.3, Trpv1, Smad3 and PP1-γ), as well as genes associated with innate immune TLR4 signaling response (Il1r1, Mapk14, Sirt1, Lrp6 and Bdnf). Functional enrichment of the miR-183C and miR-200a/b family target genes, revealed neuroinflammatory pathways networks involved in TLR4 signaling and alcohol abuse. The changes in the neuroinflammatory targets genes associated with alcohol abuse were mostly abolished in the TLR4-KO mice. Our results show the relationship between alcohol intake and miRNAs expression and open up new therapeutically targets to prevent deleterious effects of alcohol on the brain.
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Sanna MD, Galeotti N. The HDAC1/c-JUN complex is essential in the promotion of nerve injury-induced neuropathic pain through JNK signaling. Eur J Pharmacol 2018; 825:99-106. [PMID: 29477655 DOI: 10.1016/j.ejphar.2018.02.034] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 02/20/2018] [Accepted: 02/21/2018] [Indexed: 12/23/2022]
Abstract
Histone deacetylase inhibitors (HDACIs) interfere with the epigenetic process of histone acetylation and are known to have analgesic properties in models of chronic inflammatory pain. Administration of a selective HDAC1 inhibitor (LG325) in SNI-subjected mice significantly attenuated behavior related to injury-induced pain. Understanding the HDAC1 pathway in epigenetic regulation of pathological pain is of great medical relevance. Spared nerve injury (SNI) mice showed a significant increase in the HDAC1 protein levels within spinal cord in coincidence with the nociceptive phenotype at 1 and 3 weeks after nerve injury. No variation in HDAC3, DNMT3a, AcH3, MBD3 and MeCP2 levels was detected. Increased expression of HDAC1 is accompanied by activation of the JNK-c-Jun signaling pathway. A robust spinal JNK-1 overphosphorylation was observed post nerve-injury along with a selective JNK-dependent increase in p-c-Jun and HDAC1 protein levels. Co-immunoprecipitation experiments showed the presence of a heterodimeric complex between HDAC1 and c-Jun in SNI mice indicating that these transcription factors can act together to regulate transcription through heterodimerization. Stimulation of c-Jun phosphorylation was prevented by the selective HDAC1 inhibitor LG325. We found that HDAC1 was associated with c-Jun in nuclei of spinal dorsal horn astrocytes expressing JNK. On the other hand, the presence of HDAC1 and c-Jun interaction was not detected in control mice. These findings provide new insights into the mechanisms underlying the anti-nociceptive activity of HDAC inhibitors. Taken together, these data support a role for histone deacetylase in the emergence of neuropathic pain.
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Affiliation(s)
- Maria Domenica Sanna
- Department of Neurosciences, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, Viale G. Pieraccini 6, 50139 Florence, Italy.
| | - Nicoletta Galeotti
- Department of Neurosciences, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, Viale G. Pieraccini 6, 50139 Florence, Italy
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Qiu Q, Sun L, Wang XM, Lo ACY, Wong KL, Gu P, Wong SCS, Cheung CW. Propofol produces preventive analgesia via GluN2B-containing NMDA Receptor/ERK1/2 Signaling Pathway in a rat model of inflammatory pain. Mol Pain 2018; 13:1744806917737462. [PMID: 28969472 PMCID: PMC5644366 DOI: 10.1177/1744806917737462] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Abstract Propofol, an intravenous anesthetic, has been shown to offer superior analgesic effect clinically. Whether propofol has preventive analgesic property remains unexplored. The present study investigated the antinociceptive effect of propofol and underlying molecular and cellular mechanisms via pre-emptive administration in a formalin-induced inflammatory pain model in rats. Male adult Sprague–Dawley rats were randomly allocated into four groups: naïve (Group Naïve), formalin injection only (Group Formalin), and formalin injection at 30 min (Group P-30 min) or 2 h (Group P-2 h) after intravenous infusion of propofol (0.6 mg kg−1 min−1) for 1 h. Nociceptive responses and protein expression of phosphorylated- or pan-GluN2B, ERK1/2, p38 mitogen-activated protein kinase, and c-Jun N-terminal kinase in the spinal dorsal horn were evaluated. Alteration of intracellular Ca2+ concentration induced by N-methyl-D-aspartate (NMDA) receptor agonists with or without pre-treatment of propofol was measured using fluorometry in SH-SY5Y cells while neuronal activation in the spinal dorsal horn by immunofluorescence. Pre-emptive propofol reduced pain with a delayed response to formalin and a reduction in hypersensitivity that lasted at least for 2 h. The formalin-induced activation of spinal GluN2B and ERK1/2 but not p38 or c-Jun N-terminal kinase was also diminished by propofol treatment. Preconditioning treatment with 3 µM and 10 µM of propofol inhibited Ca2+ influx mediated through NMDA receptors in SH-SY5Y cells. Propofol also reduced the neuronal expression of c-Fos and p-ERK induced by formalin. This study shows that pre-emptive administration of propofol produces preventive analgesic effects on inflammatory pain through regulating neuronal GluN2B-containing NMDA receptor and ERK1/2 pathway in the spinal dorsal horn.
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Affiliation(s)
- Qiu Qiu
- Laboratory and Clinical Research Institute for Pain, Department of Anaesthesiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Liting Sun
- Laboratory and Clinical Research Institute for Pain, Department of Anaesthesiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Xiao-Min Wang
- Laboratory and Clinical Research Institute for Pain, Department of Anaesthesiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Amy C Y Lo
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Kar Lok Wong
- Department of Anesthesiology, and Institute of Clinical Medical Sciences, and Research Group of Cardiovascular Biology, China Medical University and Hospital, Taichung, Taiwan
| | - Pan Gu
- Laboratory and Clinical Research Institute for Pain, Department of Anaesthesiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Sau Ching Stanley Wong
- Laboratory and Clinical Research Institute for Pain, Department of Anaesthesiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
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18
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Ruan JP, Mao QH, Lu WG, Cai XT, Chen J, Li Q, Fu Q, Yan HJ, Cao JL, Cao P. Inhibition of spinal MAPKs by scorpion venom peptide BmK AGAP produces a sensory-specific analgesic effect. Mol Pain 2018; 14:1744806918761238. [PMID: 29424271 PMCID: PMC5844526 DOI: 10.1177/1744806918761238] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Background Several studies have shown that scorpion venom peptide BmK AGAP has an analgesic activity. Our previous study also demonstrated that intraplantar injection of BmK AGAP ameliorates formalin-induced spontaneous nociceptive behavior. However, the effect of intrathecal injection of BmK AGAP on nociceptive processing is poorly understood. Methods We investigated the effects of intrathecal injection of BmK AGAP on spinal nociceptive processing induced by chronic constrictive injury or formalin. Thermal hyperalgesia and mechanical allodynia were measured using radiant heat and the von Frey filaments test. Formalin-induced spontaneous nociceptive behavior was also investigated. C-Fos expression was assessed by immunohistochemistry. Phosphorylated mitogen-activated protein kinase (p-MAPK) expression was monitored by Western blot assay. Results Intrathecal injection of BmK AGAP reduced chronic constrictive injury-induced neuropathic pain behavior and pain from formalin-induced inflammation, accompanied by decreased expression of spinal p-MAPKs and c-Fos protein. The results of combining low doses of different MAPK inhibitor (U0126, SP600125, or SB203580; 0.1 µg for each inhibitor) with a low dose of BmK AGAP (0.2 µg) suggested that BmK AGAP could potentiate the effects of MAPK inhibitors on inflammation-associated pain. Conclusion Our results demonstrate that intrathecal injection of BmK AGAP produces a sensory-specific analgesic effect via a p-MAPK-dependent mechanism.
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Affiliation(s)
- Jia-Ping Ruan
- 1 Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, 66478 Nanjing University of Chinese Medicine , Nanjing, Jiangsu, China.,2 375808 Jiangsu Province Academy of Traditional Chinese Medicine , Nanjing, Jiangsu, China
| | - Qing-Hong Mao
- 1 Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, 66478 Nanjing University of Chinese Medicine , Nanjing, Jiangsu, China.,2 375808 Jiangsu Province Academy of Traditional Chinese Medicine , Nanjing, Jiangsu, China
| | - Wu-Guang Lu
- 1 Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, 66478 Nanjing University of Chinese Medicine , Nanjing, Jiangsu, China.,2 375808 Jiangsu Province Academy of Traditional Chinese Medicine , Nanjing, Jiangsu, China
| | - Xue-Ting Cai
- 1 Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, 66478 Nanjing University of Chinese Medicine , Nanjing, Jiangsu, China.,2 375808 Jiangsu Province Academy of Traditional Chinese Medicine , Nanjing, Jiangsu, China
| | - Jiao Chen
- 1 Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, 66478 Nanjing University of Chinese Medicine , Nanjing, Jiangsu, China.,2 375808 Jiangsu Province Academy of Traditional Chinese Medicine , Nanjing, Jiangsu, China
| | - Qing- Li
- 1 Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, 66478 Nanjing University of Chinese Medicine , Nanjing, Jiangsu, China.,2 375808 Jiangsu Province Academy of Traditional Chinese Medicine , Nanjing, Jiangsu, China
| | - Qun- Fu
- 1 Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, 66478 Nanjing University of Chinese Medicine , Nanjing, Jiangsu, China.,2 375808 Jiangsu Province Academy of Traditional Chinese Medicine , Nanjing, Jiangsu, China
| | - Huai-Jiang Yan
- 1 Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, 66478 Nanjing University of Chinese Medicine , Nanjing, Jiangsu, China.,2 375808 Jiangsu Province Academy of Traditional Chinese Medicine , Nanjing, Jiangsu, China
| | - Jun-Li Cao
- 3 Jiangsu Key Laboratory of Anesthesiology, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu, China
| | - Peng Cao
- 1 Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, 66478 Nanjing University of Chinese Medicine , Nanjing, Jiangsu, China.,2 375808 Jiangsu Province Academy of Traditional Chinese Medicine , Nanjing, Jiangsu, China
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Choi H, Roh D, Yoon S, Choi S, Kwon S, Kang S, Moon J, Han H, Beitz AJ, Lee J. Differential involvement of ipsilateral and contralateral spinal cord astrocyte D-serine in carrageenan-induced mirror-image pain: role of σ1 receptors and astrocyte gap junctions. Br J Pharmacol 2018; 175:558-572. [PMID: 29172248 PMCID: PMC5773966 DOI: 10.1111/bph.14109] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 11/04/2017] [Accepted: 11/17/2017] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND AND PURPOSE Although we have recently demonstrated that spinal astrocyte gap junctions mediate the development of mirror-image pain (MIP), it is still unclear which astrocyte-derived factor is responsible for the development of MIP and how its production is controlled. In the present study, we focused on the role of ipsilateral versus contralateral D-serine in the development of MIP and investigated the possible involvement of σ1 receptors and gap junctions in astrocyte D-serine production. EXPERIMENTAL APPROACH Following carrageenan injection, mechanical allodynia was tested at various time points to examine the effect of individual drugs. Immunohistochemistry and Western blot analyses were performed to clarify the expression levels of spinal D-serine, serine racemase, σ1 receptors and connexin 43. KEY RESULTS The expression of ipsilateral D-serine was up-regulated during the early phase of inflammation, while contralateral D-serine increased during the later phase of inflammation. The pharmacological inhibition of D-serine during the early phase blocked the development of both ipsilateral and contralateral mechanical allodynia. However, the inhibition of D-serine during the later phase of inflammation blocked contralateral, but not ipsilateral mechanical allodynia. Furthermore, the inhibition of σ1 receptors during the earlier phase of inflammation inhibited the increase in ipsilateral D-serine. Conversely, the blockade of astrocyte gap junctions suppressed the up-regulation of contralateral D-serine during the later phase of inflammation. CONCLUSION AND IMPLICATIONS Spinal astrocyte D-serine plays an important role in the development of mirror-image pain. Furthermore, σ1 receptors and astrocyte gap junction signalling mediate ipsilateral and contralateral D-serine production respectively.
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Affiliation(s)
- Hoon‐Seong Choi
- Department of Veterinary Physiology, BK21 PLUS Program for Creative Veterinary Science Research, Research Institute for Veterinary Science and College of Veterinary MedicineSeoul National UniversitySeoulKorea
| | - Dae‐Hyun Roh
- Department of Oral Physiology, School of DentistryKyung Hee UniversitySeoulKorea
| | - Seo‐Yeon Yoon
- Pain Cognitive Function Research Center, Department of Brain and Cognitive Sciences, College of Natural SciencesSeoul National UniversitySeoulKorea
| | - Sheu‐Ran Choi
- Department of Veterinary Physiology, BK21 PLUS Program for Creative Veterinary Science Research, Research Institute for Veterinary Science and College of Veterinary MedicineSeoul National UniversitySeoulKorea
| | | | - Suk‐Yun Kang
- KM Fundamental Research DivisionKorea Institute of Oriental MedicineDaejeonKorea
| | - Ji‐Young Moon
- Animal Protection & Welfare DivisionAnimal and Plant Quarantine AgencyGimcheonKorea
| | - Ho‐Jae Han
- Department of Veterinary Physiology, BK21 PLUS Program for Creative Veterinary Science Research, Research Institute for Veterinary Science and College of Veterinary MedicineSeoul National UniversitySeoulKorea
| | - Alvin J Beitz
- Department of Veterinary and Biomedical Sciences, College of Veterinary MedicineUniversity of MinnesotaSaint PaulMNUSA
| | - Jang‐Hern Lee
- Department of Veterinary Physiology, BK21 PLUS Program for Creative Veterinary Science Research, Research Institute for Veterinary Science and College of Veterinary MedicineSeoul National UniversitySeoulKorea
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20
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Jiang L, Pan CL, Wang CY, Liu BQ, Han Y, Hu L, Liu L, Yang Y, Qu JW, Liu WT. Selective suppression of the JNK-MMP2/9 signal pathway by tetramethylpyrazine attenuates neuropathic pain in rats. J Neuroinflammation 2017; 14:174. [PMID: 28859670 PMCID: PMC5580313 DOI: 10.1186/s12974-017-0947-x] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 08/23/2017] [Indexed: 12/13/2022] Open
Abstract
Background Activated astrocytes release matrix metalloproteinase-2/9 (MMP-2/9) to induce central sensitization and maintain neuropathic pain. However, the mechanisms involved in the activation of MMP-2/9 on astrocytes during pain remain poorly understood. Meanwhile, there is a lack of effective treatment to inhibit the activation of MMP-2/9 on astrocytes. In this study, we aim to investigate the effect of tetramethylpyrazine (TMP), a natural compound with analgesic effects but unknown mechanisms, on MMP-2/9 in neuropathic pain. Methods The nociception was assessed by measuring the incidence of foot withdrawal in response to mechanical indentation in rats (n = 6). Cell signaling was assayed using western blotting (n = 6) and immunohistochemistry (n = 5). The astrocyte cell line C8-D1A was cultured to investigate the in vitro effects. Results TMP significantly attenuated the maintenance of chronic constrictive injury (CCI)-induced neuropathic pain, inhibited the activation of astrocytes, and decreased the expression of MMP-2/9. Furthermore, our results indicated that TMP could selectively suppress JNK activity but had no notable effects on ERK and p38. Our study also revealed that the effect of TMP may be dependent on the inhibition of TAK1. Conclusions Inhibition of astrocyte activation in the spinal cord by tetramethylpyrazine may have utility in the treatment of CCI-induced neuroinflammation, and our results further implicate JNK-MMP-2/9 as a novel target for the attenuation of neuropathic pain. Electronic supplementary material The online version of this article (10.1186/s12974-017-0947-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lai Jiang
- Department of Pharmacology, Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Han-Zhong Road, Nanjing, 210029, China
| | - Cai-Long Pan
- Department of Pharmacology, Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Han-Zhong Road, Nanjing, 210029, China
| | - Chao-Yu Wang
- Department of Pharmacology, Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Han-Zhong Road, Nanjing, 210029, China
| | - Bing-Qian Liu
- Department of Ophthalmology, the First Affiliated Hospital with Nanjing Medical University, Nanjing, 210029, China
| | - Yuan Han
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, 221000, China
| | - Liang Hu
- Department of Pharmacology, Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Han-Zhong Road, Nanjing, 210029, China
| | - Lei Liu
- Department of pain, Shandong Qianfoshan Hospital, Shandong, 250014, China
| | - Yang Yang
- Department of Gynecologic Oncology, Jiangsu Institute of Cancer Research, Jiangsu Cancer Hospital, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, Jiangsu, 210009, China
| | - Jun-Wei Qu
- Department of Gynecologic Oncology, Jiangsu Institute of Cancer Research, Jiangsu Cancer Hospital, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, Jiangsu, 210009, China
| | - Wen-Tao Liu
- Department of Pharmacology, Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Han-Zhong Road, Nanjing, 210029, China.
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21
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Sanna MD, Ghelardini C, Galeotti N. Spinal astrocytic c-Jun N-terminal kinase (JNK) activation as counteracting mechanism to the amitriptyline analgesic efficacy in painful peripheral neuropathies. Eur J Pharmacol 2017; 798:85-93. [DOI: 10.1016/j.ejphar.2017.01.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 01/19/2017] [Accepted: 01/19/2017] [Indexed: 12/19/2022]
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Yang YJ, Hu L, Xia YP, Jiang CY, Miao C, Yang CQ, Yuan M, Wang L. Resveratrol suppresses glial activation and alleviates trigeminal neuralgia via activation of AMPK. J Neuroinflammation 2016; 13:84. [PMID: 27093858 PMCID: PMC4837542 DOI: 10.1186/s12974-016-0550-6] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 04/11/2016] [Indexed: 12/14/2022] Open
Abstract
Background Glial activation and neuroinflammation in the spinal trigeminal nucleus (STN) play a pivotal role in the genesis and maintenance of trigeminal neuralgia (TN). Resveratrol, a natural compound from grape and red wine, has a potential anti-inflammatory effect. We hypothesized that resveratrol could significantly suppress neuroinflammation in the STN mediated by glial activation and further relieve TN. In this study, we evaluated whether resveratrol could alleviate trigeminal allodynia and explore the mechanism underlying the antinociceptive effect of resveratrol. Methods Animals were orally injected with resveratrol after chronic constriction injury (CCI) of the infraorbital nerve. Mechanical thresholds of the affected whisker pad were measured to assess nociceptive behaviors. The STN was harvested to quantify the changing levels of p-NR1, p-PKC, TNF-α, and IL1-β by western blotting and detect the expression of calcitonin gene-related peptide (CGRP) and c-Fos by immunofluorescence. Glial activation was observed by immunofluorescence and western blotting. Mitogen-activated protein kinase (MAPK) phosphorylation in vivo and in vitro was examined by western blotting. Results We found that resveratrol significantly attenuated trigeminal allodynia dose-dependently and decreased the increased expression of CGRP and c-Fos in the STN. Additionally, resveratrol showed an inhibitory effect on CCI-evoked astrocyte and microglia activation and reduced production of pro-inflammatory cytokines in the STN. Furthermore, the antinociceptive effect of resveratrol was partially mediated by reduced phosphorylation of MAP kinases via adenosine monophosphate-activated protein kinase (AMPK) activation. Conclusions AMPK activation in the STN glia via resveratrol has utility in the treatment of CCI-induced neuroinflammation and further implicates AMPK as a novel target for the attenuation of trigeminal neuralgia.
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Affiliation(s)
- Yan-jing Yang
- Jiangsu Key Laboratory of Oral Disease, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, People's Republic of China.
| | - Liang Hu
- Jiangsu Key Laboratory of Neurodegeneration, Department of Pharmacology, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, People's Republic of China
| | - Ye-peng Xia
- Jiangsu Key Laboratory of Oral Disease, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, People's Republic of China
| | - Chun-yi Jiang
- Jiangsu Key Laboratory of Neurodegeneration, Department of Pharmacology, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, People's Republic of China
| | - Chen Miao
- Department of Pathology, First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, Jiangsu, 210029, People's Republic of China
| | - Chun-qing Yang
- Department of Pathology, First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, Jiangsu, 210029, People's Republic of China
| | - Miao Yuan
- Jiangsu Key Laboratory of Oral Disease, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, People's Republic of China
| | - Lin Wang
- Jiangsu Key Laboratory of Oral Disease, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, People's Republic of China.
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Ohnou T, Yokai M, Kurihara T, Hasegawa-Moriyama M, Shimizu T, Inoue K, Kambe Y, Kanmura Y, Miyata A. Pituitary adenylate cyclase-activating polypeptide type 1 receptor signaling evokes long-lasting nociceptive behaviors through the activation of spinal astrocytes in mice. J Pharmacol Sci 2016; 130:194-203. [PMID: 26948958 DOI: 10.1016/j.jphs.2016.01.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2015] [Revised: 01/21/2016] [Accepted: 01/25/2016] [Indexed: 12/14/2022] Open
Abstract
Intrathecal (i.t.) administration of pituitary adenylate cyclase-activating polypeptide (PACAP) induces long-lasting nociceptive behaviors for more than 60 min in mice, while the involvement of PACAP type1 receptor (PAC1-R) has not been clarified yet. The present study investigated signaling mechanisms of the PACAP-induced prolonged nociceptive behaviors. Single i.t. injection of a selective PAC1-R agonist, maxadilan (Max), mimicked nociceptive behaviors in a dose-dependent manner similar to PACAP. Pre- or post-treatment of a selective PAC1-R antagonist, max.d.4, significantly inhibited the nociceptive behaviors by PACAP or Max. Coadministration of a protein kinase A inhibitor, Rp-8-Br-cAMPS, a mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase inhibitor, PD98059 or a c-Jun N-terminal kinase (JNK) inhibitor, SP600125, significantly inhibited the nociceptive behaviors by Max. Immunohistochemistry and immunoblotting analysis revealed that spinal administration of Max-induced ERK phosphorylation and JNK phosphorylation, and also augmented an astrocyte marker, glial fibrillary acidic protein in mouse spinal cord. Furthermore, an astroglial toxin, l-α-aminoadipate, significantly attenuated the development of the nociceptive behaviors and ERK phosphorylation by Max. These results suggest that the activation of spinal PAC1-R induces long-lasting nociception through the interaction of neurons and astrocytes.
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Affiliation(s)
- Tetsuya Ohnou
- Department of Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan; Department of Anesthesiology and Critical Care Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan
| | - Masafumi Yokai
- Department of Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan
| | - Takashi Kurihara
- Department of Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan
| | - Maiko Hasegawa-Moriyama
- Department of Anesthesiology and Critical Care Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan
| | - Takao Shimizu
- Department of Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan
| | - Kazuhiko Inoue
- Department of Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan
| | - Yuki Kambe
- Department of Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan
| | - Yuichi Kanmura
- Department of Anesthesiology and Critical Care Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan
| | - Atsuro Miyata
- Department of Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima City, Kagoshima 890-8544, Japan.
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A new minimally-invasive method for microinjection into the mouse spinal dorsal horn. Sci Rep 2015; 5:14306. [PMID: 26387932 PMCID: PMC4585681 DOI: 10.1038/srep14306] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 08/24/2015] [Indexed: 12/30/2022] Open
Abstract
Noninvasive gene delivery to the spinal dorsal horn (SDH) remains challenging because existing methods to directly microinject vectors require laminectomy, which leads to tissue damage and inflammation. Such responses might hamper accurate readouts of cellular and behavioural effects of an introduced gene. Here we develop a new minimally-invasive SDH microinjection technique without the need of laminectomy in which a microcapillary is inserted into the SDH parenchyma through an intervertebral space. Using this method, we microinjected adeno-associated virus with an astrocytic promoter into the SDH and achieved efficient gene expression in an astrocyte-specific manner without gliosis, neuronal loss or inflammation. Furthermore, astrocytic loss- and gain-of-function of the transcription factor STAT3 by expressing a dominant-negative form and a constitutive-active form of STAT3, respectively, demonstrated the necessity and sufficiency of astrocytic STAT3 in the maintenance of neuropathic pain following peripheral nerve injury, a debilitating chronic pain state in which currently available treatments are frequently ineffective. Thus, our technique enables manipulation of gene expression in cell type- and spatial-specific manners without adverse effects, and may be useful for research in SDH physiology and pathology.
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Tsuda M. Microglia in the spinal cord and neuropathic pain. J Diabetes Investig 2015; 7:17-26. [PMID: 26813032 PMCID: PMC4718109 DOI: 10.1111/jdi.12379] [Citation(s) in RCA: 166] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 05/13/2015] [Accepted: 05/16/2015] [Indexed: 12/13/2022] Open
Abstract
In contrast to physiological pain, pathological pain is not dependent on the presence of tissue‐damaging stimuli. One type of pathological pain – neuropathic pain – is often a consequence of nerve injury or of diseases such as diabetes. Neuropathic pain can be agonizing, can persist over long periods and is often resistant to known painkillers. A growing body of evidence shows that many pathological processes within the central nervous system are mediated by complex interactions between neurons and glial cells. In the case of painful peripheral neuropathy, spinal microglia react and undergo a series of changes that directly influence the establishment of neuropathic pain states. After nerve damage, purinergic P2X4 receptors (non‐selective cation channels activated by extracellular adenosine triphosphate) are upregulated in spinal microglia in a manner that depends on the transcription factors interferon regulatory factor 8 and 5, both of which are expressed in microglia after peripheral nerve injury. P2X4 receptor expression on the cell surface of microglia is also regulated at the post‐translational level by signaling from CC chemokine receptor chemotactic cytokine receptor 2. Furthermore, spinal microglia in response to extracellular stimuli results in signal transduction through intracellular signaling cascades, such as mitogen‐activated protein kinases, p38 and extracellular signal‐regulated protein kinase. Importantly, inhibiting the function or expression of these microglial molecules suppresses the aberrant excitability of dorsal horn neurons and neuropathic pain. These findings show that spinal microglia are a central player in mechanisms for neuropathic pain, and might be a potential target for treating the chronic pain state.
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Affiliation(s)
- Makoto Tsuda
- Department of Life Innovation Graduate School of Pharmaceutical Sciences Kyushu University Fukuoka Japan
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Wan C, Zhang Y, Jiang J, Jiang S, Nie X, Li A, Guo A, Wu Q. Critical Role of TAK1-Dependent Nuclear Factor-κB Signaling in 2,3,7,8-Tetrachlorodibenzo-p-dioxin-induced Astrocyte Activation and Subsequent Neuronal Death. Neurochem Res 2015; 40:1220-31. [PMID: 25998883 DOI: 10.1007/s11064-015-1585-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 02/02/2015] [Accepted: 04/20/2015] [Indexed: 12/21/2022]
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has been recently shown to elicit inflammatory response in a number of cell-types. However, whether TCDD could provoke inflammation in astrocytes, the most abundant glial cells in central nervous system (CNS), remains virtually unknown. In the present study, we showed that TCDD exposure could induce evident astrocyte activation both in vivo and in vitro. Further, we found that TGF-β-activated kinase 1 (TAK1), a critical regulator of NF-κB signaling, was rapidly phosphorylated in the process of TCDD-induced reactive astroglia. Exposure to TCDD led to rapid TAK1 and NF-κB p65 phosphorylation, as well as IKBα degradation. Moreover, blockage of TAK1 using siRNA oligos or TAK1 inhibitor 5Z-7-oxozeaenol significantly attenuated TCDD-induced astrocyte activation as well as the release of TNF-α. Finally, we showed that the conditioned medium of TCDD-treated astrocytes promoted the apoptosis of PC12 neuronal cells, which could be blocked with the pre-treatment of TAK1 inhibitor. Taken together, these findings suggested that TCDD could promote the inflammatory activation of astrocytes through modulating TAK1-NF-κB cascade, implicating that reactive astrocytes might contribute to TCDD-induced adverse effects on CNS system.
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Affiliation(s)
- Chunhua Wan
- Department of Nutrition and Food Hygieney, School of Public Health, Nantong University, Nantong, 226001, Jiangsu Province, People's Republic of China
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Xu H, Xu T, Ma X, Jiang W. Involvement of neuronal TGF-β activated kinase 1 in the development of tolerance to morphine-induced antinociception in rat spinal cord. Br J Pharmacol 2015; 172:2892-904. [PMID: 25625840 DOI: 10.1111/bph.13094] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 01/15/2015] [Accepted: 01/20/2015] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND AND PURPOSE Tolerance induced by morphine and other opiates remains a major unresolved problem in the clinical management of pain. There is now good evidence for the importance of MAPKs in morphine-induced antinociceptive tolerance. A member of the MAPK kinase kinase family, TGF-β activated kinase 1 (TAK1) is the common upstream kinase of MAPKs. Here, we have assessed the involvement of TAK1 in the development of tolerance to morphine-induced analgesia. EXPERIMENTAL APPROACH The effects of an antagonist of TAK1 on morphine tolerance were investigated in vivo using the Randall-Selitto test, and the mechanism was investigated using Western blot and immunohistochemistry. The expression of TAK1 after chronic morphine exposure was also evaluated in vitro by immunohistochemistry. KEY RESULTS Chronic intrathecal morphine exposure up-regulated protein levels and phosphorylation of spinal TAK1. TAK1 immunoreactivity was co-localized with the neuronal marker NeuN. Intrathecal administration of 5Z-7-oxozeaenol (OZ), a selective TAK1 inhibitor, attenuated the loss of morphine analgesic potency and morphine-induced TAK1 up-regulation. Furthermore, OZ decreased the up-regulated expression of spinal p38 and JNK after repeated morphine exposure. In vitro studies demonstrated that sustained morphine treatment induced TAK1 up-regulation, which was reversed by co-administration of OZ. A bolus injection of OZ showed some reversal of established morphine antinociceptive tolerance. CONCLUSIONS AND IMPLICATIONS TAK1 played a pivotal role in the development of morphine-induced antinociceptive tolerance. Modulation of TAK1 activation by the selective inhibitor OZ in the lumbar spinal cord may prove to be an attractive adjuvant therapy to attenuate such tolerance.
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Affiliation(s)
- Hao Xu
- Department of Anesthesiology, Shanghai Jiaotong University Affiliated Shanghai Sixth People's Hospital, Shanghai, China
| | - Tao Xu
- Department of Anesthesiology, Shanghai Jiaotong University Affiliated Shanghai Sixth People's Hospital, Shanghai, China
| | - Xiaqing Ma
- Department of Anesthesiology, Shanghai Jiaotong University Affiliated Shanghai Sixth People's Hospital, Shanghai, China
| | - Wei Jiang
- Department of Anesthesiology, Shanghai Jiaotong University Affiliated Shanghai Sixth People's Hospital, Shanghai, China
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Alfonso Romero-Sandoval E, Sweitzer S. Nonneuronal central mechanisms of pain: glia and immune response. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 131:325-58. [PMID: 25744678 DOI: 10.1016/bs.pmbts.2014.11.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The role of central glial cells in the mechanisms underlying pain has been intensively studied in the last two decades. Most studies on glia and pain focused on the potential detrimental role of glial cells following noxious stimulus/insults manifested as an "activation" or a "reactive" state (increase in glial marker expression and production of proinflammatory/nociceptive molecules). Therefore, "activated" or "reactive" glial cells became a target for the future generation of drugs to treat chronic pain. Several glial modulators that reduce the activation of glial cells have shown great efficacy in multiple animal (rodents mostly) models of pain (acute, subacute, chronic, inflammatory, neuropathic, surgical, etc.). These encouraging findings inspired clinical trials that have been completed in the last 5 years. Unfortunately, all clinical trials with these glial modulators have failed to demonstrate efficacy for the treatment of pain. New lines of investigation and elegant experimental designs are shedding light on alternative glial functions, which demonstrate that "glial reactivity" is not necessarily deleterious in some pathological conditions. New strategies to validate findings through our current animal models are necessary to enhance the translational value of our preclinical studies. Also, more studies using human subjects would enhance our understanding of glial cells in the context of pain. This chapter explores the available literature to objectively ponder the potential role of glial cells in human pain conditions.
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Affiliation(s)
- E Alfonso Romero-Sandoval
- Department of Pharmaceutical and Administrative Sciences, Presbyterian College School of Pharmacy, Clinton, South Carolina, USA.
| | - Sarah Sweitzer
- Department of Pharmaceutical and Administrative Sciences, Presbyterian College School of Pharmacy, Clinton, South Carolina, USA
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Wu HH, Yin JB, Zhang T, Cui YY, Dong YL, Chen GZ, Wang W. Inhibiting spinal neuron-astrocytic activation correlates with synergistic analgesia of dexmedetomidine and ropivacaine. PLoS One 2014; 9:e92374. [PMID: 24658263 PMCID: PMC3962412 DOI: 10.1371/journal.pone.0092374] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2014] [Accepted: 02/21/2014] [Indexed: 02/07/2023] Open
Abstract
Background This study aims to identify that intrathecal (i.t.) injection of dexmedetomidine (Dex) and ropivacaine (Ropi) induces synergistic analgesia on chronic inflammatory pain and is accompanied with corresponding “neuron-astrocytic” alterations. Methods Male, adult Sprague-Dawley rats were randomly divided into sham, control and i.t. medication groups. The analgesia profiles of i.t. Dex, Ropi, and their combination detected by Hargreaves heat test were investigated on the subcutaneous (s.c.) injection of complete Freund adjuvant (CFA) induced chronic pain in rat and their synergistic analgesia was confirmed by using isobolographic analysis. During consecutive daily administration, pain behavior was daily recorded, and immunohistochemical staining was applied to investigate the number of Fos-immunoreactive (Fos-ir) neurons on hour 2 and day 1, 3 and 7, and the expression of glial fibrillary acidic protein (GFAP) within the spinal dorsal horn (SDH) on day 1, 3, 5 and 7 after s.c. injection of CFA, respectively, and then Western blot to examine spinal GFAP and β-actin levels on day 3 and 7. Results i.t. Dex or Ropi displayed a short-term analgesia in a dose-dependent manner, and consecutive daily administrations of their combination showed synergistic analgesia and remarkably down-regulated neuronal and astrocytic activations indicated by decreases in the number of Fos-ir neurons and the GFAP expression within the SDH, respectively. Conclusion i.t. co-delivery of Dex and Ropi shows synergistic analgesia on the chronic inflammatory pain, in which spinal “neuron-astrocytic activation” mechanism may play an important role.
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Affiliation(s)
- Huang-Hui Wu
- Department of Anesthesiology, Fuzhou General Hospital of Nanjing Military Region, Fuzhou, PR China
| | - Jun-Bin Yin
- Department of Anatomy, Histology and Embryology & K.K. Leung Brain Research Centre, Preclinical School of Medicine, Fourth Military Medical University, Xi’an, PR China
| | - Ting Zhang
- Department of Anatomy, Histology and Embryology & K.K. Leung Brain Research Centre, Preclinical School of Medicine, Fourth Military Medical University, Xi’an, PR China
| | - Yuan-Yuan Cui
- Department of Anatomy, Histology and Embryology & K.K. Leung Brain Research Centre, Preclinical School of Medicine, Fourth Military Medical University, Xi’an, PR China
| | - Yu-Lin Dong
- Department of Anatomy, Histology and Embryology & K.K. Leung Brain Research Centre, Preclinical School of Medicine, Fourth Military Medical University, Xi’an, PR China
| | - Guo-Zhong Chen
- Department of Anesthesiology, Fuzhou General Hospital of Nanjing Military Region, Fuzhou, PR China
- * E-mail: (GZC); (WW)
| | - Wen Wang
- Department of Anatomy, Histology and Embryology & K.K. Leung Brain Research Centre, Preclinical School of Medicine, Fourth Military Medical University, Xi’an, PR China
- * E-mail: (GZC); (WW)
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Ji RR, Berta T, Nedergaard M. Glia and pain: is chronic pain a gliopathy? Pain 2013; 154 Suppl 1:S10-S28. [PMID: 23792284 PMCID: PMC3858488 DOI: 10.1016/j.pain.2013.06.022] [Citation(s) in RCA: 791] [Impact Index Per Article: 71.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Revised: 05/23/2013] [Accepted: 06/12/2013] [Indexed: 12/22/2022]
Abstract
Activation of glial cells and neuro-glial interactions are emerging as key mechanisms underlying chronic pain. Accumulating evidence has implicated 3 types of glial cells in the development and maintenance of chronic pain: microglia and astrocytes of the central nervous system (CNS), and satellite glial cells of the dorsal root and trigeminal ganglia. Painful syndromes are associated with different glial activation states: (1) glial reaction (ie, upregulation of glial markers such as IBA1 and glial fibrillary acidic protein (GFAP) and/or morphological changes, including hypertrophy, proliferation, and modifications of glial networks); (2) phosphorylation of mitogen-activated protein kinase signaling pathways; (3) upregulation of adenosine triphosphate and chemokine receptors and hemichannels and downregulation of glutamate transporters; and (4) synthesis and release of glial mediators (eg, cytokines, chemokines, growth factors, and proteases) to the extracellular space. Although widely detected in chronic pain resulting from nerve trauma, inflammation, cancer, and chemotherapy in rodents, and more recently, human immunodeficiency virus-associated neuropathy in human beings, glial reaction (activation state 1) is not thought to mediate pain sensitivity directly. Instead, activation states 2 to 4 have been demonstrated to enhance pain sensitivity via a number of synergistic neuro-glial interactions. Glial mediators have been shown to powerfully modulate excitatory and inhibitory synaptic transmission at presynaptic, postsynaptic, and extrasynaptic sites. Glial activation also occurs in acute pain conditions, and acute opioid treatment activates peripheral glia to mask opioid analgesia. Thus, chronic pain could be a result of "gliopathy," that is, dysregulation of glial functions in the central and peripheral nervous system. In this review, we provide an update on recent advances and discuss remaining questions.
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Affiliation(s)
- Ru-Rong Ji
- Department of Anesthesiology and Neurobiology, Duke University Medical Center, Durham, NC, USA
| | - Temugin Berta
- Department of Anesthesiology and Neurobiology, Duke University Medical Center, Durham, NC, USA
| | - Maiken Nedergaard
- Division of Glial Disease and Therapeutics, Center for Translational Neuromedicine, University of Rochester, Rochester, NY, USA
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Lee JY, Choi DC, Oh TH, Yune TY. Analgesic effect of acupuncture is mediated via inhibition of JNK activation in astrocytes after spinal cord injury. PLoS One 2013; 8:e73948. [PMID: 24040124 PMCID: PMC3767587 DOI: 10.1371/journal.pone.0073948] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 07/23/2013] [Indexed: 11/19/2022] Open
Abstract
Acupuncture (AP) has been used worldwide to relieve pain. However, the mechanism of action of AP is poorly understood. Here, we found that AP relieved neuropathic pain (NP) by inhibiting Jun-N-terminal kinase (JNK) activation in astrocytes after spinal cord injury (SCI). After contusion injury which induces the below-level (L4-L5) NP, Shuigou (GV26) and Yanglingquan (GB34) acupoints were applied. At 31 d after injury, both mechanical allodynia and thermal hyperalgesia were significantly alleviated by AP applied at GV26 and GB34. Immunocytochemistry revealed that JNK activation was mainly observed in astrocytes after injury. AP inhibited JNK activation in astrocytes at L4-L5 level of spinal cord. The level of p-c-Jun known, a downstream molecule of JNK, was also decreased by AP. In addition, SCI-induced GFAP expression, a marker for astrocytes, was decreased by AP as compared to control groups. Especially, the number of hypertrophic, activated astrocytes in laminae I–II of dorsal horn at L4-5 was markedly decreased by AP treatment when compared with vehicle and simulated AP-treated groups. When animals treated with SP600125, a specific JNK inhibitor, after SCI, both mechanical allodynia and thermal hyperalgesia were significantly attenuated by the inhibitor, suggesting that JNK activation is likely involved in SCI-induced NP. Also, the expression of chemokines which is known to be mediated through JNK pathway was significantly decreased by AP and SP600125 treatment. Therefore, our results indicate that analgesic effect of AP is mediated in part by inhibiting JNK activation in astrocytes after SCI.
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Affiliation(s)
- Jee Y. Lee
- Age-Related and Brain Diseases Research Center, Kyung Hee University, Seoul, Korea
- Neurodegeneration Control Research Center, Kyung Hee University, Seoul, Korea
| | - Doo C. Choi
- Age-Related and Brain Diseases Research Center, Kyung Hee University, Seoul, Korea
| | - Tae H. Oh
- Age-Related and Brain Diseases Research Center, Kyung Hee University, Seoul, Korea
| | - Tae Y. Yune
- Age-Related and Brain Diseases Research Center, Kyung Hee University, Seoul, Korea
- Neurodegeneration Control Research Center, Kyung Hee University, Seoul, Korea
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul, Korea
- * E-mail:
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Inner ear supporting cells: rethinking the silent majority. Semin Cell Dev Biol 2013; 24:448-59. [PMID: 23545368 DOI: 10.1016/j.semcdb.2013.03.009] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Accepted: 03/21/2013] [Indexed: 11/21/2022]
Abstract
Sensory epithelia of the inner ear contain two major cell types: hair cells and supporting cells. It has been clear for a long time that hair cells play critical roles in mechanoreception and synaptic transmission. In contrast, until recently the more abundant supporting cells were viewed as serving primarily structural and homeostatic functions. In this review, we discuss the growing information about the roles that supporting cells play in the development, function and maintenance of the inner ear, their activities in pathological states, their potential for hair cell regeneration, and the mechanisms underlying these processes.
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Astrocytes--multitaskers in chronic pain. Eur J Pharmacol 2013; 716:120-8. [PMID: 23528354 DOI: 10.1016/j.ejphar.2013.03.023] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2012] [Revised: 02/20/2013] [Accepted: 03/04/2013] [Indexed: 12/31/2022]
Abstract
Treatment of chronic pain remains a clinical challenge and sufficient pharmacological management is difficult to achieve without concurrent adverse drug effects. Recently the concept of chronic pain as a solely neuron-mediated phenomenon has evolved and it is now appreciated that also glial cells are of critical importance in pain generation and modulation. Astrocytes are macroglial cells that have close structural relationships with neurons; they contact neuronal somata and dendrites and enwrap synapses, where small astrocytic processes have been shown to be highly motile. This organization allows astrocytes to directly influence and coordinate neurons located within their structural domains. Moreover, astrocytes form astroglial networks and calcium wave propagations can spread through neighbouring astrocytes. ATP, which is released from astrocytes in response to elevated intracellular calcium concentrations, can contribute to the central mechanisms in chronic pain via purinergic receptors. In this review we highlight the structural organization and the functionalities of astrocytes that allow them to undertake critical roles in pain processing and we stress the possibility that astrocytes contribute to chronic pain not via a single pathway, but by undertaking various roles depending on the pain condition.
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Characterization of frequency-dependent responses of the vascular system to repetitive vibration. J Occup Environ Med 2013; 54:1010-6. [PMID: 22785326 DOI: 10.1097/jom.0b013e318255ba74] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
OBJECTIVE Occupational exposure to hand-transmitted vibration can result in damage to nerves and sensory loss. The goal of this study was to assess the frequency-dependent effects of repeated bouts of vibration on sensory nerve function and associated changes in nerves. METHODS The tails of rats were exposed to vibration at 62.5, 125, or 250 Hz (constant acceleration of 49 m/s2) for 10 days. The effects on sensory nerve function, nerve morphology, and transcript expression in ventral tail nerves were measured. RESULTS Vibration at all frequencies had effects on nerve function and physiology. However, the effects tended to be more prominent with exposure at 250 Hz. CONCLUSION Exposure to vibration has detrimental effects on sensory nerve function and physiology. However, many of these changes are more prominent at 250-Hz exposure than at lower frequencies.
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Ikeda H, Kiritoshi T, Murase K. Contribution of microglia and astrocytes to the central sensitization, inflammatory and neuropathic pain in the juvenile rat. Mol Pain 2012; 8:43. [PMID: 22703840 PMCID: PMC3418174 DOI: 10.1186/1744-8069-8-43] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Accepted: 06/15/2012] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND The development of pain after peripheral nerve and tissue injury involves not only neuronal pathways but also immune cells and glia. Central sensitization is thought to be a mechanism for such persistent pain, and ATP involves in the process. We examined the contribution of glia to neuronal excitation in the juvenile rat spinal dorsal horn which is subjected to neuropathic and inflammatory pain. RESULTS In rats subjected to neuropathic pain, immunoreactivity for the microglial marker OX42 was markedly increased. In contrast, in rats subjected to inflammatory pain, immunoreactivity for the astrocyte marker glial fibrillary acidic protein was increased slightly. Optically-recorded neuronal excitation induced by single-pulse stimulation to the dorsal root was augmented in rats subjected to neuropathic and inflammatory pain compared to control rats. The bath application of a glial inhibitor minocycline and a p38 mitogen-activated protein kinase inhibitor SB203580 inhibited the neuronal excitation in rats subjected to neuropathic pain. A specific P2X1,2,3,4 antagonist TNP-ATP largely inhibited the neuronal excitation only in rats subjected to neuropathic pain rats. In contrast, an astroglial toxin L-alpha-aminoadipate, a gap junction blocker carbenoxolone and c-Jun N-terminal kinase inhibitor SP600125 inhibited the neuronal excitation only in rats subjected to inflammatory pain. A greater number of cells in spinal cord slices from rats subjected to neuropathic pain showed Ca2+ signaling in response to puff application of ATP. This Ca2+ signaling was inhibited by minocycline and TNP-ATP. CONCLUSIONS These results directly support the notion that microglia is more involved in neuropathic pain and astrocyte in inflammatory pain.
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Affiliation(s)
- Hiroshi Ikeda
- Department of Human and Artificial Intelligence Systems, Graduate School of Engineering; Research and Education Program for Life Science, University of Fukui, 3-9-1 Bunkyo, Fukui, 910-8507, Japan
| | - Takaki Kiritoshi
- Department of Human and Artificial Intelligence Systems, Graduate School of Engineering; Research and Education Program for Life Science, University of Fukui, 3-9-1 Bunkyo, Fukui, 910-8507, Japan
| | - Kazuyuki Murase
- Department of Human and Artificial Intelligence Systems, Graduate School of Engineering; Research and Education Program for Life Science, University of Fukui, 3-9-1 Bunkyo, Fukui, 910-8507, Japan
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Liang Y, Jiang W, Zhang Z, Yu J, Tao L, Zhao S. Behavioral and Morphological Evidence for the Involvement of Glial Cells in the Antinociceptive Effect of Najanalgesin in a Rat Neuropathic Pain Model. Biol Pharm Bull 2012; 35:850-4. [DOI: 10.1248/bpb.35.850] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Yingxia Liang
- Department of Anesthesiology, Weifang Medical University
| | | | - Zhiyu Zhang
- Department of Microsurgery, The People’s Hospital of Shouguang
| | - Jianfeng Yu
- Department of Anesthesiology, Weifang Medical University
| | - Liang Tao
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University
| | - Shujin Zhao
- South China Center for Innovative Pharmaceuticals
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Sodium arsenite dependent protein expression analysis on human embryonic carcinoma (NCCIT) cell line. Toxicol Lett 2011; 207:149-58. [DOI: 10.1016/j.toxlet.2011.09.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Revised: 09/01/2011] [Accepted: 09/02/2011] [Indexed: 01/23/2023]
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Purinergic system, microglia and neuropathic pain. Curr Opin Pharmacol 2011; 12:74-9. [PMID: 22036170 DOI: 10.1016/j.coph.2011.10.014] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 10/12/2011] [Accepted: 10/12/2011] [Indexed: 01/23/2023]
Abstract
Extracellular nucleotides play pivotal roles in the regulation of neuronal and glial functions in the nervous system through P2X receptors (P2XRs) and P2Y receptors (P2YRs). A growing body of evidence shows that microglia express several subtypes of P2XRs and P2YRs, and that these receptors play a key role in pain signaling in the spinal cord under pathological conditions, such as following peripheral nerve injury (neuropathic pain). Following peripheral nerve injury, dorsal horn microglia become activated and show upregulated expression of purinergic receptors, and interference with the function or expression of these receptors strongly suppresses neuropathic pain. This article highlights recent advances that further increase our understanding of the mechanisms by which microglial purinergic receptors contribute to the pathogenesis of neuropathic pain.
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Inoue K, Tsuda M. Purinergic systems, neuropathic pain and the role of microglia. Exp Neurol 2011; 234:293-301. [PMID: 21946271 DOI: 10.1016/j.expneurol.2011.09.016] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Revised: 09/01/2011] [Accepted: 09/09/2011] [Indexed: 01/23/2023]
Abstract
We have learned various data on the role of purinoceptors (P2X4, P2X7, P2Y6 and P2Y12) expressed in spinal microglia and several factors that presumably activate microglia in neuropathic pain after peripheral nerve injury. Purinergic receptor-mediated spinal microglial functions make a critical contribution to pathologically enhanced pain processing in the dorsal horn. Microglial purinoceptors might be promising targets for treating neuropathic pain. A predicted therapeutic benefit of interfering with microglial purinergic receptors may be that normal pain sensitivity would be unaffected since expression or activity of most of these receptors are upregulated or enhanced predominantly in activated microglia in the spinal cord where damaged sensory fibers project.
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Affiliation(s)
- Kazuhide Inoue
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi, Fukuoka 812-8582, Japan.
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40
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Tsuda M, Kohro Y, Yano T, Tsujikawa T, Kitano J, Tozaki-Saitoh H, Koyanagi S, Ohdo S, Ji RR, Salter MW, Inoue K. JAK-STAT3 pathway regulates spinal astrocyte proliferation and neuropathic pain maintenance in rats. ACTA ACUST UNITED AC 2011; 134:1127-39. [PMID: 21371995 DOI: 10.1093/brain/awr025] [Citation(s) in RCA: 222] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Neuropathic pain, a debilitating pain condition, is a common consequence of damage to the nervous system. Optimal treatment of neuropathic pain is a major clinical challenge because the underlying mechanisms remain unclear and currently available treatments are frequently ineffective. Emerging lines of evidence indicate that peripheral nerve injury converts resting spinal cord glia into reactive cells that are required for the development and maintenance of neuropathic pain. However, the mechanisms underlying reactive astrogliosis after nerve injury are largely unknown. In the present study, we investigated cell proliferation, a critical process in reactive astrogliosis, and determined the temporally restricted proliferation of dorsal horn astrocytes in rats with spinal nerve injury, a well-known model of neuropathic pain. We found that nerve injury-induced astrocyte proliferation requires the Janus kinase-signal transducers and activators of transcription 3 signalling pathway. Nerve injury induced a marked signal transducers and activators of transcription 3 nuclear translocation, a primary index of signal transducers and activators of transcription 3 activation, in dorsal horn astrocytes. Intrathecally administering inhibitors of Janus kinase-signal transducers and activators of transcription 3 signalling to rats with nerve injury reduced the number of proliferating dorsal horn astrocytes and produced a recovery from established tactile allodynia, a cardinal symptom of neuropathic pain that is characterized by pain hypersensitivity evoked by innocuous stimuli. Moreover, recovery from tactile allodynia was also produced by direct suppression of dividing astrocytes by intrathecal administration of the cell cycle inhibitor flavopiridol to nerve-injured rats. Together, these results imply that the Janus kinase-signal transducers and activators of transcription 3 signalling pathway are critical transducers of astrocyte proliferation and maintenance of tactile allodynia and may be a therapeutic target for neuropathic pain.
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Affiliation(s)
- Makoto Tsuda
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan
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Dickinson BD, Head CA, Gitlow S, Osbahr AJ. Maldynia: pathophysiology and management of neuropathic and maladaptive pain--a report of the AMA Council on Science and Public Health. PAIN MEDICINE 2011; 11:1635-53. [PMID: 21044254 DOI: 10.1111/j.1526-4637.2010.00986.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Because of disparate taxonomic arrays for classification, the American Academy of Pain Medicine has proposed categorizing pain on a neurobiologic basis as eudynia (nociceptive pain), Greek for "good pain," or maldynia (maladaptive pain), Greek for "bad pain." The latter has been viewed as maladaptive because it may occur in the absence of ongoing noxious stimuli and does not promote healing and repair. OBJECTIVE To address recent findings on the pathogenesis of pain following neural injury and consider whether the development of maladaptive pain justifies its classification as a disease and to briefly discuss the scope of pharmacologic and non-pharmacologic approaches employed in patients with such pain. METHODS English language reports on studies using human subjects were selected from a PubMed search of the literature from 1995 to August 2010 and from the Cochrane Library. Further information was obtained from Internet sites of medical specialty and other societies devoted to pain management. RESULTS Neural damage to either the peripheral or central nervous system provokes multiple processes including peripheral and central sensitization, ectopic activity, neuronal cell death, disinhibition, altered gene expression, and abnormal sprouting and cellular connectivity. A series of neuro-immune interactions underlie many of these mechanisms. Imaging studies have shown that such damage is characterized by functional, structural, and chemical changes in the brain. Such pain is maladaptive in the sense that it occurs in the absence of ongoing noxious stimuli and does not promote healing and repair. CONCLUSION As defined, maldynia is a multidimensional process that may warrant consideration as a chronic disease not only affecting sensory and emotional processing but also producing an altered brain state based on both functional imaging and macroscopic measurements. However, the absolute clinical value of this definition is not established.
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Affiliation(s)
- Barry D Dickinson
- Council on Science and Public Health, American Medical Association, Chicago, Illinois 60654, USA.
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Gao YJ, Zhang L, Ji RR. Spinal injection of TNF-α-activated astrocytes produces persistent pain symptom mechanical allodynia by releasing monocyte chemoattractant protein-1. Glia 2011; 58:1871-80. [PMID: 20737477 DOI: 10.1002/glia.21056] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Accumulating evidence suggests that spinal astrocytes play an important role in the genesis of persistent pain, by increasing the activity of spinal cord nociceptive neurons, i.e., central sensitization. However, direct evidence of whether activation of astrocytes is sufficient to induce chronic pain symptoms is lacking. We investigated whether and how spinal injection of activated astrocytes could produce mechanical allodynia, a cardinal feature of chronic pain, in naïve mice. Spinal (intrathecal) injection of astrocytes, which were prepared from cerebral cortexes of neonatal mice and briefly stimulated by tumor necrosis factor-alpha (TNF-α), induced a substantial decrease in paw withdrawal thresholds, indicating the development of mechanical allodynia. This allodynia was prevented when the astrocyte cultures were pretreated with a peptide inhibitor of c-Jun N-terminal kinase (JNK), D-JNKI-1. Of note a short exposure of astrocytes to TNF-α for 15 min dramatically increased the expression and release of the chemokine monocyte chemoattractant protein-1 (MCP-1), even 3 h after TNF-α withdrawal, in a JNK-dependent manner. In parallel, intrathecal administration of TNF-α induced MCP-1 expression in spinal cord astrocytes. In particular, mechanical allodynia induced by TNF-α-activated astrocytes was reversed by a MCP-1 neutralizing antibody. Finally, pretreatment of astrocytes with MCP-1 siRNA attenuated astrocytes-induced mechanical allodynia. Taken together, our results suggest that activated astrocytes are sufficient to produce persistent pain symptom in naïve mice by releasing MCP-1.
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Affiliation(s)
- Yong-Jing Gao
- Sensory Plasticity Laboratory, Department of Anesthesiology, Brigham and Women's Hospital and Harvard Medical School, Pain Research Center, Boston, Massachusetts 02115, USA.
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Mei XP, Zhang H, Wang W, Wei YY, Zhai MZ, Wang W, Xu LX, Li YQ. Inhibition of spinal astrocytic c-Jun N-terminal kinase (JNK) activation correlates with the analgesic effects of ketamine in neuropathic pain. J Neuroinflammation 2011; 8:6. [PMID: 21255465 PMCID: PMC3033337 DOI: 10.1186/1742-2094-8-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Accepted: 01/24/2011] [Indexed: 01/08/2023] Open
Abstract
Background We have previously reported that inhibition of astrocytic activation contributes to the analgesic effects of intrathecal ketamine on spinal nerve ligation (SNL)-induced neuropathic pain. However, the underlying mechanisms are still unclear. c-Jun N-terminal kinase (JNK), a member of mitogen-activated protein kinase (MAPK) family, has been reported to be critical for spinal astrocytic activation and neuropathic pain development after SNL. Ketamine can decrease lipopolysaccharide (LPS)-induced phosphorylated JNK (pJNK) expression and could thus exert its anti-inflammatory effect. We hypothesized that inhibition of astrocytic JNK activation might be involved in the suppressive effect of ketamine on SNL-induced spinal astrocytic activation. Methods Immunofluorescence histochemical staining was used to detect SNL-induced spinal pJNK expression and localization. The effects of ketamine on SNL-induced mechanical allodynia were confirmed by behavioral testing. Immunofluorescence histochemistry and Western blot were used to quantify the SNL-induced spinal pJNK expression after ketamine administration. Results The present study showed that SNL induced ipsilateral pJNK up-regulation in astrocytes but not microglia or neurons within the spinal dorsal horn. Intrathecal ketamine relieved SNL-induced mechanical allodynia without interfering with motor performance. Additionally, intrathecal administration of ketamine attenuated SNL-induced spinal astrocytic JNK activation in a dose-dependent manner, but not JNK protein expression. Conclusions The present results suggest that inhibition of JNK activation may be involved in the suppressive effects of ketamine on SNL-induced spinal astrocyte activation. Therefore, inhibition of spinal JNK activation may be involved in the analgesic effects of ketamine on SNL-induced neuropathic pain.
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Affiliation(s)
- Xiao-Peng Mei
- Department of Anesthesiology, School of Stomatology, Fourth Military Medical University, Xi'an, PR China
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Noguchi K, Okubo M. Leukotrienes in Nociceptive Pathway and Neuropathic/Inflammatory Pain. Biol Pharm Bull 2011; 34:1163-9. [DOI: 10.1248/bpb.34.1163] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Koichi Noguchi
- Department of Anatomy and Neuroscience, Hyogo College of Medicine
| | - Masamichi Okubo
- Department of Anatomy and Neuroscience, Hyogo College of Medicine
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45
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Gao YJ, Ji RR. Targeting astrocyte signaling for chronic pain. Neurotherapeutics 2010; 7:482-93. [PMID: 20880510 PMCID: PMC2950097 DOI: 10.1016/j.nurt.2010.05.016] [Citation(s) in RCA: 301] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2010] [Revised: 05/18/2010] [Accepted: 05/19/2010] [Indexed: 12/20/2022] Open
Abstract
Clinical management of chronic pain after nerve injury (neuropathic pain) and tumor invasion (cancer pain) is a real challenge due to our limited understanding of the cellular mechanisms that initiate and maintain chronic pain. It has been increasingly recognized that glial cells, such as microglia and astrocytes in the CNS play an important role in the development and maintenance of chronic pain. Notably, astrocytes make very close contacts with synapses and astrocyte reaction after nerve injury, arthritis, and tumor growth is more persistent than microglial reaction, and displays a better correlation with chronic pain behaviors. Accumulating evidence indicates that activated astrocytes can release pro-inflammatory cytokines (e.g., interleukin [IL]-1β) and chemokines (e.g., monocyte chemoattractant protein-1 [MCP-1]/also called CCL2) in the spinal cord to enhance and prolong persistent pain states. IL-1β can powerfully modulate synaptic transmission in the spinal cord by enhancing excitatory synaptic transmission and suppressing inhibitory synaptic transmission. IL-1β activation (cleavage) in the spinal cord after nerve injury requires the matrix metalloprotease-2. In particular, nerve injury and inflammation activate the c-Jun N-terminal kinase in spinal astrocytes, leading to a substantial increase in the expression and release of MCP-1. The MCP-1 increases pain sensitivity via direct activation of NMDA receptors in dorsal horn neurons. Pharmacological inhibition of the IL-1β, c-Jun N-terminal kinase, MCP-1, or matrix metalloprotease-2 signaling via spinal administration has been shown to attenuate inflammatory, neuropathic, or cancer pain. Therefore, interventions in specific signaling pathways in astrocytes may offer new approaches for the management of chronic pain.
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Affiliation(s)
- Yong-Jing Gao
- grid.62560.370000000403788294Department of Anesthesiology, Sensory Plasticity Laboratory, Pain Research Center, Brigham and Women’s Hospital and Harvard Medical School, 02115 Boston, Massachusetts
| | - Ru-Rong Ji
- grid.62560.370000000403788294Department of Anesthesiology, Sensory Plasticity Laboratory, Pain Research Center, Brigham and Women’s Hospital and Harvard Medical School, 02115 Boston, Massachusetts
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Mei XP, Wang W, Wang W, Zhu C, Chen L, Zhang T, Xu LX, Wu SX, Li YQ. Combining ketamine with astrocytic inhibitor as a potential analgesic strategy for neuropathic pain ketamine, astrocytic inhibitor and pain. Mol Pain 2010; 6:50. [PMID: 20815929 PMCID: PMC2942826 DOI: 10.1186/1744-8069-6-50] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Accepted: 09/06/2010] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Neuropathic pain is an intractable clinical problem. Intrathecal ketamine, a noncompetitive N-methyl-D-aspartate receptor (NMDAR) antagonist, is reported to be useful for treating neuropathic pain in clinic by inhibiting the activity of spinal neurons. Nevertheless, emerging studies have disclosed that spinal astrocytes played a critical role in the initiation and maintenance of neuropathic pain. However, the present clinical therapeutics is still just concerning about neuronal participation. Therefore, the present study is to validate the coadministration effects of a neuronal noncompetitive N-methyl-D-aspartate receptor (NMDAR) antagonist ketamine and astrocytic cytotoxin L-α-aminoadipate (LAA) on spinal nerve ligation (SNL)-induced neuropathic pain. RESULTS Intrathecal ketamine (10, 100, 1000 μg/kg) or LAA (10, 50, 100 nmol) alleviated SNL-induced mechanical allodynia in a dose-dependent manner respectively. Phosphorylated NR1 (pNR1) or glial fibrillary acidic protein (GFAP) expression was down-regulated by intrathecal ketamine (100, 1000 μg/kg) or LAA (50, 100 nmol) respectively. The combination of ketamine (100 μg/kg) with LAA (50 nmol) showed superadditive effects on neuropathic pain compared with that of intrathecal administration of either ketamine or LAA alone. Combined administration obviously relieved mechanical allodynia in a quick and stable manner. Moreover, down-regulation of pNR1 and GFAP expression were also enhanced by drugs coadministration. CONCLUSIONS These results suggest that combining NMDAR antagonist ketamine with an astrocytic inhibitor or cytotoxin, which is suitable for clinical use once synthesized, might be a potential strategy for clinical management of neuropathic pain.
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Affiliation(s)
- Xiao-Peng Mei
- Department of Anesthesiology, School of Stomatology, Fourth Military Medical University, Xi'an, China
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Abstract
BACKGROUND The discovery that glial activation plays a critical role in the modulation of neuronal functions and affects the spinal processing of nociceptive signalling has brought new understanding on the mechanisms underlying central sensitization involved in chronic pain facilitation. Spinal glial activation is now considered an important component in the development and maintenance of allodynia and hyperalgesia in various models of chronic pain, including neuropathic pain and pain associated with peripheral inflammation. In addition, spinal glial activation is also involved in some forms of visceral hyperalgesia. PURPOSE We discuss the signalling pathways engaged in central glial activation, including stress pathways, and the neuron-glia bidirectional relationships involved in the modulation of synaptic activity and pain facilitation. In this expanding field of research, the characterization of the mechanisms by which glia affect spinal neuro-transmission will increase our understanding of central pain facilitation, and has the potential for the development of new therapeutic agents for common chronic pain conditions.
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Affiliation(s)
- S Bradesi
- Center for Neurobiology of Stress, Department of Medicine, David Geffen School of Medicine at UCLA, VAGLA HC, Los Angeles, CA, USA.
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Okubo M, Yamanaka H, Kobayashi K, Noguchi K. Leukotriene synthases and the receptors induced by peripheral nerve injury in the spinal cord contribute to the generation of neuropathic pain. Glia 2010; 58:599-610. [PMID: 19908283 DOI: 10.1002/glia.20948] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Leukotrienes (LTs) belong to a large family of lipid mediators, termed eicosanoids, which are derived from arachidonic acids and released from the cell membrane by phospholipases. LTs are involved in the pathogenesis of inflammatory diseases, such as asthma, rheumatoid arthritis, and peripheral inflammatory pain. In the present study, we examined whether LTs were implicated in pathomechanism of neuropathic pain following peripheral nerve injury. Using the spared nerve injury (SNI) model in rats, we investigated the expression of LT synthases (5-lipoxygenase; 5-LO, Five lipoxygenase activating protein; FLAP, LTA4 hydrolase; LTA4h and LTC4 synthase; LTC4s) and receptors (BLT1, 2 and CysLT1, 2) mRNAs in the rat spinal cord. Semi-quantitative RT-PCR revealed that 5-LO, FLAP, LTC4s, BLT1, and CysLT1 mRNAs increased following SNI, but not CysLT2 mRNAs. Using double labeling analysis of in situ hybridization with immunohistochemistry, we observed that 5-LO, FLAP, and CysLT1 mRNAs were expressed in spinal microglia. LTA4h and LTC4s mRNAs were expressed in both spinal neurons and microglia. BLT1 mRNA was expressed in spinal neurons. The p38 mitogen-activated protein kinase inhibitor, but not MEK inhibitor, reduced the increase in 5-LO in spinal microglia. Continuous intrathecal administration of the 5-LO inhibitor or BLT1 and CysLT1 receptor antagonists suppressed mechanical allodynia induced by SNI. Our findings suggest that the increase of LT synthesis in spinal microglia produced via p38 MAPK plays a role in the generation of neuropathic pain.
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Affiliation(s)
- Masamichi Okubo
- Department of Anatomy and Neuroscience, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo, Japan
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Gao YJ, Xu ZZ, Liu YC, Wen YR, Decosterd I, Ji RR. The c-Jun N-terminal kinase 1 (JNK1) in spinal astrocytes is required for the maintenance of bilateral mechanical allodynia under a persistent inflammatory pain condition. Pain 2010; 148:309-319. [PMID: 20022176 DOI: 10.1016/j.pain.2009.11.017] [Citation(s) in RCA: 131] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2009] [Revised: 09/22/2009] [Accepted: 11/16/2009] [Indexed: 12/20/2022]
Abstract
Peripheral inflammation induces persistent central sensitization characterized by mechanical allodynia and heat hyperalgesia that are mediated by distinct mechanisms. Compared to well-demonstrated mechanisms of heat hyperalgesia, mechanisms underlying the development of mechanical allodynia and contralateral pain are incompletely known. In this study, we investigated the distinct role of spinal JNK in heat hyperalgesia, mechanical allodynia, and contralateral pain in an inflammatory pain model. Intraplantar injection of complete Freund's adjuvant (CFA) induced bilateral mechanical allodynia but unilateral heat hyperalgesia. CFA also induced a bilateral activation (phosphorylation) of JNK in the spinal cord, and the phospho JNK1 (pJNK1) levels were much higher than that of pJNK2. Notably, both pJNK and JNK1 were expressed in GFAP-positive astrocytes. Intrathecal infusion of a selective peptide inhibitor of JNK, D-JNKI-1, starting before inflammation via an osmotic pump, reduced CFA-induced mechanical allodynia in the maintenance phase but had no effect on CFA-induced heat hyperalgesia. A bolus intrathecal injection of D-JNKI-1 or SP600126, a small molecule inhibitor of JNK also reversed mechanical allodynia bilaterally. In contrast, peripheral (intraplantar) administration of D-JNKI-1 reduced the induction of CFA-induced heat hyperalgesia but did not change mechanical allodynia. Finally, CFA-induced bilateral mechanical allodynia was attenuated in mice lacking JNK1 but not JNK2. Taken together, our data suggest that spinal JNK, in particular JNK1 plays an important role in the maintenance of persistent inflammatory pain. Our findings also reveal a unique role of JNK1 and astrocyte network in regulating tactile allodynia and contralateral pain.
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Affiliation(s)
- Yong-Jing Gao
- Sensory Plasticity Laboratory, Pain Research Center, Department of Anesthesiology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA Institute of Nautical Medicine, Nantong University, Nantong 226001, China Department of Anesthesiology, Shin-Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan Anesthesiology Pain Research Group, Anesthesiology Department, University Hospital Center and University of Lausanne CH-1011 Lausanne, Switzerland Department of Cell Biology and Morphology, University of Lausanne, CH-1005 Lausanne, Switzerland
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Expression genetics identifies spinal mechanisms supporting formalin late phase behaviors. Mol Pain 2010; 6:11. [PMID: 20149257 PMCID: PMC2831877 DOI: 10.1186/1744-8069-6-11] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Accepted: 02/11/2010] [Indexed: 12/30/2022] Open
Abstract
Background Formalin injection into rodent hind paws is one of the most commonly employed pain assays. The resulting nocifensive behaviors can be divided into two phases differing in timing, duration and underlying mechanisms. Spinal sensitization has long been felt to participate in the second phase of this response, although this sensitization is incompletely understood. By using correlative analysis between spinal gene expression and mouse strain-dependent intensity of late phase behavior, we hypothesized genes participating in variability of the response could be identified. Results Late phase formalin behavior scores among 10 inbred mouse strains were correlated with a spinal cord gene expression database constructed using expression arrays. Messenger RNA levels for several genes were highly correlated with the late phase behavioral responses. Most of these genes had already been implicated in mechanisms regulating pain and analgesia. One of the most strongly correlated genes, Mapk8 coding for c-Jun N-terminal kinase 1 (JNK1), was chosen for further analysis. Studies using additional strains of mice confirmed that spinal cord mRNA expression levels of Mapk8 followed the pattern predicted by strain-specific levels of formalin behavior. Interestingly, spinal cord JNK1 protein levels displayed an inverse relationship with mRNA measurements. Finally, intrathecal injections of the selective JNK inhibitor, SP600125, selectively reduced late phase licking behavior. Conclusions Wide differences in pain behaviors, including those resulting from the injection of formalin, can be observed in inbred strains of mice suggesting strong genetic influences. Correlating levels of gene expression in tissues established to be mechanistically implicated in the expression of specific behaviors can identify genes involved in the behaviors of interest. Comparing formalin late phase behavior levels with spinal cord gene expression yielded several plausible gene candidates, including the Mapk8 gene. Additional molecular and pharmacologic evidence confirmed a functional role for this gene in supporting formalin late phase responses.
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