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Reddy P, Vasudeva J, Shah D, Prajapati JN, Harikumar N, Barik A. A Deep-Learning Driven Investigation of the Circuit Basis for Reflexive Hypersensitivity to Thermal Pain. Neuroscience 2023; 530:158-172. [PMID: 37640138 DOI: 10.1016/j.neuroscience.2023.08.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 08/14/2023] [Accepted: 08/15/2023] [Indexed: 08/31/2023]
Abstract
Objectively measuring animal behavior is vital to understanding the neural circuits underlying pain. Recent progress in machine vision has presented unprecedented scope in behavioral analysis. Here, we apply DeepLabCut (DLC) to dissect mouse behavior on the thermal-plate test - a commonly used paradigm to ascertain supraspinal contributions to noxious thermal sensation and pain hypersensitivity. We determine the signature characteristics of the pattern of mouse movement and posture in 3D in response to a range of temperatures from innocuous to noxious on the thermal-plate test. Next, we test how acute chemical and chronic inflammatory injuries sensitize mouse behaviors. Repeated exposure to noxious temperatures on the thermal plate can induce learning. In this study, we design a novel assay and formulate an analytical pipeline to facilitate the dissection of plasticity mechanisms in pain circuits in the brain. Last, we record and test how activating Tacr1 expressing PBN neurons (PBNTacr1) - a population responsive to sustained noxious stimuli- affects mouse behavior on the thermal plate test. Taken together, we demonstrate that by tracking a single body part of a mouse, we can reveal the behavioral signatures of mice exposed to noxious surface temperatures, report the alterations of the same when injured, and determine if a molecularly and anatomically defined pain-responsive circuit plays a role in the reflexive hypersensitivity to thermal pain.
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Affiliation(s)
- Prannay Reddy
- Center for Neuroscience, Division of Biological Sciences, Indian Institute of Science, Gulmohar Marg, Bengaluru, Karnataka 560012, India
| | - Jayesh Vasudeva
- Center for Neuroscience, Division of Biological Sciences, Indian Institute of Science, Gulmohar Marg, Bengaluru, Karnataka 560012, India
| | - Devanshi Shah
- Center for Neuroscience, Division of Biological Sciences, Indian Institute of Science, Gulmohar Marg, Bengaluru, Karnataka 560012, India
| | - Jagat Narayan Prajapati
- Center for Neuroscience, Division of Biological Sciences, Indian Institute of Science, Gulmohar Marg, Bengaluru, Karnataka 560012, India
| | - Nikhila Harikumar
- Center for Neuroscience, Division of Biological Sciences, Indian Institute of Science, Gulmohar Marg, Bengaluru, Karnataka 560012, India
| | - Arnab Barik
- Center for Neuroscience, Division of Biological Sciences, Indian Institute of Science, Gulmohar Marg, Bengaluru, Karnataka 560012, India.
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Terzoni S, Mora C, Cloconi C, Gaia G, Sighinolfi MC, Maruccia S, Rocco B, Pinna B, Ferrara P, Parozzi M, Destrebecq A. Transcutaneous electrical nerve stimulation for pelvic pain: A scoping review of treatment protocols, practical indications, and caveats. Neurourol Urodyn 2023; 42:631-640. [PMID: 36701176 DOI: 10.1002/nau.25137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 01/18/2023] [Indexed: 01/27/2023]
Abstract
BACKGROUND Neuromodulation (NM) is a family of therapies based on electrical stimulation to target specific nerves that control LUTS (Lower Urinary Tract Symptoms) and pain. The aim is to modulate what is happening within the nervous system to achieve therapeutic effects. A particular type of neuromodulation, called TENS (Transcutaneous Electrical Nerve Stimulation), has proven effective for treating pelvic pain. The available evidence provides indications regarding the many aspects of TENS that influence therapeutic effects, but a comprehensive review has yet to be conducted. METHODS Scoping review on Pubmed, CINAHL, Embase, Scopus, and Web of Science, including clinical trials, reviews, case studies or series, and other descriptive studies, according to the Joanna Briggs and PRISMA methodology. RESULTS The 31 papers retrieved allowed the formulation of precise indications about the DOs and DON'Ts of electrode placement, waveform, pulse duration, pulse frequency, amplitude, session duration, and frequency of sessions. This paper also discusses the biochemical and neuro urological mechanisms of TENS. CONCLUSION TENS effectiveness is influenced by many factors, some self-evident, others subtle, which this paper elucidates. Pelvic pain requires a multimodal approach, of which TENS is just a part. TENS should therefore be viewed as one of the components of the rehabilitation program in the frame of thorough and continuous patient assessment.
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Affiliation(s)
- Stefano Terzoni
- San Paolo bachelor school of Nursing, ASST Santi Paolo e Carlo, Milan, Italy
| | - Cristina Mora
- Department of Urology, ASST Santi Paolo e Carlo, Milan, Italy
| | | | - Giorgia Gaia
- Department of Gynecology, ASST Santi Paolo e Carlo, Milan, Italy
| | | | - Serena Maruccia
- Department of Urology, ASST Santi Paolo e Carlo, Milan, Italy
| | - Bernardo Rocco
- Department of Urology, University of Milan, Milan, Italy
| | - Barbara Pinna
- Nursing Management Office, ASST Santi Paolo e Carlo, Milan, Italy
| | - Paolo Ferrara
- San Paolo bachelor school of Nursing, ASST Santi Paolo e Carlo, Milan, Italy
| | - Mauro Parozzi
- San Paolo bachelor school of Nursing, ASST Santi Paolo e Carlo, Milan, Italy
| | - Anne Destrebecq
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy
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Martin KK, Noble DJ, Parvin S, Jang K, Garraway SM. Pharmacogenetic inhibition of TrkB signaling in adult mice attenuates mechanical hypersensitivity and improves locomotor function after spinal cord injury. Front Cell Neurosci 2022; 16:987236. [PMID: 36226073 PMCID: PMC9548551 DOI: 10.3389/fncel.2022.987236] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 09/01/2022] [Indexed: 11/24/2022] Open
Abstract
Brain-derived neurotrophic factor (BDNF) signals through tropomyosin receptor kinase B (TrkB), to exert various types of plasticity. The exact involvement of BDNF and TrkB in neuropathic pain states after spinal cord injury (SCI) remains unresolved. This study utilized transgenic TrkBF616 mice to examine the effect of pharmacogenetic inhibition of TrkB signaling, induced by treatment with 1NM-PP1 (1NMP) in drinking water for 5 days, on formalin-induced inflammatory pain, pain hypersensitivity, and locomotor dysfunction after thoracic spinal contusion. We also examined TrkB, ERK1/2, and pERK1/2 expression in the lumbar spinal cord and trunk skin. The results showed that formalin-induced pain responses were robustly attenuated in 1NMP-treated mice. Weekly assessment of tactile sensitivity with the von Frey test showed that treatment with 1NMP immediately after SCI blocked the development of mechanical hypersensitivity up to 4 weeks post-SCI. Contrastingly, when treatment started 2 weeks after SCI, 1NMP reversibly and partially attenuated hind-paw hypersensitivity. Locomotor scores were significantly improved in the early-treated 1NMP mice compared to late-treated or vehicle-treated SCI mice. 1NMP treatment attenuated SCI-induced increases in TrkB and pERK1/2 levels in the lumbar cord but failed to exert similar effects in the trunk skin. These results suggest that early onset TrkB signaling after SCI contributes to maladaptive plasticity that leads to spinal pain hypersensitivity and impaired locomotor function.
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Mazzitelli M, Presto P, Antenucci N, Meltan S, Neugebauer V. Recent Advances in the Modulation of Pain by the Metabotropic Glutamate Receptors. Cells 2022; 11:2608. [PMID: 36010684 PMCID: PMC9406805 DOI: 10.3390/cells11162608] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/16/2022] [Accepted: 08/18/2022] [Indexed: 01/22/2023] Open
Abstract
Metabotropic glutamate receptors (mGluR or mGlu) are G-protein coupled receptors activated by the binding of glutamate, the main classical neurotransmitter of the nervous system. Eight different mGluR subtypes (mGluR1-8) have been cloned and are classified in three groups based on their molecular, pharmacological and signaling properties. mGluRs mediate several physiological functions such as neuronal excitability and synaptic plasticity, but they have also been implicated in numerous pathological conditions including pain. The availability of new and more selective allosteric modulators together with the canonical orthosteric ligands and transgenic technologies has led to significant advances in our knowledge about the role of the specific mGluR subtypes in the pathophysiological mechanisms of various diseases. Although development of successful compounds acting on mGluRs for clinical use has been scarce, the subtype-specific-pharmacological manipulation might be a compelling approach for the treatment of several disorders in humans, including pain; this review aims to summarize and update on preclinical evidence for the roles of different mGluRs in the pain system and discusses knowledge gaps regarding mGluR-related sex differences and neuroimmune signaling in pain.
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Affiliation(s)
- Mariacristina Mazzitelli
- Department of Pharmacology and Neuroscience, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Peyton Presto
- Department of Pharmacology and Neuroscience, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Nico Antenucci
- Department of Pharmacology and Neuroscience, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Shakira Meltan
- Department of Pharmacology and Neuroscience, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Volker Neugebauer
- Department of Pharmacology and Neuroscience, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
- Center of Excellence for Translational Neuroscience and Therapeutics, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
- Garrison Institute on Aging, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
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Ito A, Fukaya M, Okamoto H, Sakagami H. Physiological and Pathological Roles of the Cytohesin Family in Neurons. Int J Mol Sci 2022; 23:5087. [PMID: 35563476 PMCID: PMC9104363 DOI: 10.3390/ijms23095087] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 05/01/2022] [Accepted: 05/02/2022] [Indexed: 02/05/2023] Open
Abstract
The cytohesin proteins, consisting of four closely related members (cytohesins-1, -2, -3, and -4), are a subfamily of the Sec7 domain-containing guanine nucleotide exchange factors for ADP ribosylation factors (Arfs), which are critical regulators of membrane trafficking and actin cytoskeleton remodeling. Recent advances in molecular biological techniques and the development of a specific pharmacological inhibitor for cytohesins, SecinH3, have revealed the functional involvement of the cytohesin-Arf pathway in diverse neuronal functions from the formation of axons and dendrites, axonal pathfinding, and synaptic vesicle recycling, to pathophysiological processes including chronic pain and neurotoxicity induced by proteins related to neurodegenerative disorders, such as amyotrophic lateral sclerosis and Alzheimer's disease. Here, we review the physiological and pathological roles of the cytohesin-Arf pathway in neurons and discuss the future directions of this research field.
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Affiliation(s)
- Akiko Ito
- Department of Anesthesiology, Kitasato University School of Medicine, Sagamihara 252-0374, Kanagawa, Japan; (A.I.); (H.O.)
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara 252-0374, Kanagawa, Japan;
| | - Masahiro Fukaya
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara 252-0374, Kanagawa, Japan;
| | - Hirotsugu Okamoto
- Department of Anesthesiology, Kitasato University School of Medicine, Sagamihara 252-0374, Kanagawa, Japan; (A.I.); (H.O.)
| | - Hiroyuki Sakagami
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara 252-0374, Kanagawa, Japan;
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Xia J, Dou Y, Mei Y, Munoz FM, Gao R, Gao X, Li D, Osei-Owusu P, Schiffenhaus J, Bekker A, Tao YX, Hu H. Orai1 is a crucial downstream partner of group I metabotropic glutamate receptor signaling in dorsal horn neurons. Pain 2022; 163:652-664. [PMID: 34252911 PMCID: PMC8741882 DOI: 10.1097/j.pain.0000000000002396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 06/18/2021] [Indexed: 11/25/2022]
Abstract
ABSTRACT Group I metabotropic glutamate receptors (group I mGluRs) have been implicated in several central nervous system diseases including chronic pain. It is known that activation of group I mGluRs results in the production of inositol triphosphate (IP3) and diacylglycerol that leads to activation of extracellular signal-regulated kinases (ERKs) and an increase in neuronal excitability, but how group I mGluRs mediate this process remains unclear. We previously reported that Orai1 is responsible for store-operated calcium entry and plays a key role in central sensitization. However, how Orai1 is activated under physiological conditions is unknown. Here, we tested the hypothesis that group I mGluRs recruit Orai1 as part of its downstream signaling pathway in dorsal horn neurons. We demonstrate that neurotransmitter glutamate induces STIM1 puncta formation, which is not mediated by N-Methyl-D-aspartate (NMDA) or α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors. Glutamate-induced Ca2+ entry in the presence of NMDA or AMPA receptor antagonists is eliminated in Orai1-deficient neurons. Dihydroxyphenylglycine (DHPG) (an agonist of group I mGluRs)-induced Ca2+ entry is abolished by Orai1 deficiency, but not affected by knocking down of transient receptor potential cation channel 1 (TRPC1) or TRPC3. Dihydroxyphenylglycine-induced activation of ERKs and modulation of neuronal excitability are abolished in cultured Orai1-deficient neurons. Moreover, DHPG-induced nociceptive behavior is markedly reduced in Orai1-deficient mice. Our findings reveal previously unknown functional coupling between Orai1 and group I mGluRs and shed light on the mechanism underlying group I mGluRs-mediated neuronal plasticity.
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Affiliation(s)
- Jingsheng Xia
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102
| | - Yannong Dou
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102
| | - Yixiao Mei
- Department of Anesthesiology, Rutgers New Jersey Medical School, Newark, NJ 07103
| | - Frances M. Munoz
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102
| | - Ruby Gao
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102
| | - Xinghua Gao
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102
| | - Daling Li
- Department of Anesthesiology, Rutgers New Jersey Medical School, Newark, NJ 07103
| | - Patrick Osei-Owusu
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102
| | - James Schiffenhaus
- Department of Anesthesiology, Rutgers New Jersey Medical School, Newark, NJ 07103
| | - Alex Bekker
- Department of Anesthesiology, Rutgers New Jersey Medical School, Newark, NJ 07103
| | - Yuan-Xiang Tao
- Department of Anesthesiology, Rutgers New Jersey Medical School, Newark, NJ 07103
| | - Huijuan Hu
- Department of Anesthesiology, Rutgers New Jersey Medical School, Newark, NJ 07103
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, PA 19102
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7
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Haroun RAH, Osman WH, Amin RE, Hassan AK, Abo-Shanab WS, Eessa AM. Circulating plasma miR-155 is a potential biomarker for the detection of SARS-CoV-2 infection. Pathology 2021; 54:104-110. [PMID: 34838331 PMCID: PMC8570980 DOI: 10.1016/j.pathol.2021.09.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 09/06/2021] [Accepted: 09/12/2021] [Indexed: 12/16/2022]
Abstract
Identification of human miRNAs involved in coronavirus-host interplay is important due to the current COVID-19 pandemic. Therefore, this study aimed to measure the circulating plasma miR-155 expression level in COVID-19 patients and healthy controls to investigate its roles in the pathogenesis and severity of COVID-19 disease and to assess its usefulness as a clinical biomarker for the detection of COVID-19 disease and the severity of infection. A total of 150 COVID-19 patients and 50 controls were enrolled into our study. Beside the routine laboratory work and chest computed tomography (CT) scans of COVID-19 patients, plasma miR-155 expression level was measured using reverse transcription quantitative real-time PCR (RT-qPCR) technique. Our results demonstrated increased miR-155 expression level in COVID-19 patients compared to controls, in severe compared to moderate COVID-19 patients, and in non-survival compared to survival COVID-19 patients. miR-155 expression level also had significant correlation with clinicopathological characteristics of COVID-19 patients such as chest CT findings, CRP, ferritin, mortality, D-dimer, WBC count, and lymphocytes and neutrophils percentages. Also, our results showed that the area under the curve (AUC) for miR-155 was 0.986 with 90% sensitivity and 100% specificity when used as a biomarker for the detection of COVID-19 disease; while in detection of severity of COVID-19 disease, AUC for miR-155 was 0.75 with 76% sensitivity and specificity. From these results we can conclude that miR-155 has a crucial role in the pathogenesis and severity of COVID-19; also, it could be a good diagnostic clinical biomarker for the detection of COVID-19 disease and the severity of infection.
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Affiliation(s)
| | - Waleed H Osman
- Department of Biochemistry, Faculty of Science, Ain Shams University, Cairo, Egypt
| | - Rasha E Amin
- Department of Clinical and Chemical Pathology, Faculty of Medicine, Port-Said University, Port-Said, Egypt
| | - Ahmad K Hassan
- Department of Zoology, Faculty of Science, Port-Said University, Port-Said, Egypt
| | - Waleed S Abo-Shanab
- Department of Radiodiagnosis, Faculty of Medicine, Port-Said University, Port-Said, Egypt
| | - Asmaa M Eessa
- Department of Geriatric Medicine and Gerontology, Faculty of Medicine, Port-Said University, Port-Said, Egypt
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Cytohesin-2 mediates group I metabotropic glutamate receptor-dependent mechanical allodynia through the activation of ADP ribosylation factor 6 in the spinal cord. Neurobiol Dis 2021; 159:105466. [PMID: 34390832 DOI: 10.1016/j.nbd.2021.105466] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 07/20/2021] [Accepted: 08/02/2021] [Indexed: 01/15/2023] Open
Abstract
Group I metabotropic glutamate receptors (mGluRs), mGluR1 and mGluR5, in the spinal cord are implicated in nociceptive transmission and plasticity through G protein-mediated second messenger cascades leading to the activation of various protein kinases such as extracellular signal-regulated kinase (ERK). In this study, we demonstrated that cytohesin-2, a guanine nucleotide exchange factor for ADP ribosylation factors (Arfs), is abundantly expressed in subsets of excitatory interneurons and projection neurons in the superficial dorsal horn. Cytohesin-2 is enriched in the perisynapse on the postsynaptic membrane of dorsal horn neurons and forms a protein complex with mGluR5 in the spinal cord. Central nervous system-specific cytohesin-2 conditional knockout mice exhibited reduced mechanical allodynia in inflammatory and neuropathic pain models. Pharmacological blockade of cytohesin catalytic activity with SecinH3 similarly reduced mechanical allodynia and inhibited the spinal activation of Arf6, but not Arf1, in both pain models. Furthermore, cytohesin-2 conditional knockout mice exhibited reduced mechanical allodynia and ERK1/2 activation following the pharmacological activation of spinal mGluR1/5 with 3,5-dihydroxylphenylglycine (DHPG). The present study suggests that cytothesin-2 is functionally associated with mGluR5 during the development of mechanical allodynia through the activation of Arf6 in spinal dorsal horn neurons.
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9
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Yang Y, Zhao J, Li Y, Li X, Chen X, Feng Z. Fragile X mental retardation protein-regulated proinflammatory cytokine expression in the spinal cord contributes to the pathogenesis of inflammatory pain induced by complete Freund's adjuvant. J Neurochem 2021; 159:512-524. [PMID: 34338322 DOI: 10.1111/jnc.15485] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 07/18/2021] [Accepted: 07/26/2021] [Indexed: 11/25/2022]
Abstract
Studies have verified that Fragile X mental retardation protein (FMRP), an RNA-binding protein, plays a potential role in the pathogenesis of formalin- and (RS)-3,5-dihydroxyphenylglycine (DHPG)-induced abnormal pain sensations. However, the role of FMRP in inflammatory pain has not been reported. Here, we showed an increase in FMRP expression in the spinal dorsal horn (SDH) in a rat model of inflammatory pain induced by complete Freund's adjuvant (CFA). Double immunofluorescence staining revealed that FMRP was mainly expressed in spinal neurons and colocalized with proinflammatory cytokines [tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6)]. After consecutive intrathecal injection of fragile X mental retardation 1 (Fmr1) small interfering RNA (siRNA) for 3 days post-CFA injection, FMRP expression in the SDH was reduced, and CFA-induced hyperalgesia was decreased. In addition, the CFA-induced increase in spinal TNF-α and IL-6 production was significantly suppressed by intrathecal administration of Fmr1 siRNA. Together, these results suggest that FMRP regulates TNF-α and IL-6 levels in the SDH and plays an important role in inflammatory pain.
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Affiliation(s)
- Yixin Yang
- Department of Pain Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine.,Department of Anesthesiology, Ningbo City First Hospital, Ningbo, Zhejiang, China
| | - Jinsong Zhao
- Department of Pain Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine.,Department of Anesthesiology, Ningbo NO.6 Hospital, Ningbo, Zhejiang, China
| | - Yunze Li
- Department of Pain Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine
| | - Xiangyao Li
- Institute of Neuroscience, Key Laboratory of Medical Neurobiology, Ministry of Health of China, School of Medicine, Zhejiang University
| | - Xiaowei Chen
- Zhejiang Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, Ningbo, China
| | - Zhiying Feng
- Department of Pain Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine
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Sampson PB. Phytocannabinoid Pharmacology: Medicinal Properties of Cannabis sativa Constituents Aside from the "Big Two". JOURNAL OF NATURAL PRODUCTS 2021; 84:142-160. [PMID: 33356248 DOI: 10.1021/acs.jnatprod.0c00965] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Plant-based therapies date back centuries. Cannabis sativa is one such plant that was used medicinally up until the early part of the 20th century. Although rich in diverse and interesting phytochemicals, cannabis was largely ignored by the modern scientific community due to its designation as a schedule 1 narcotic and restrictions on access for research purposes. There was renewed interest in the early 1990s when the endocannabinoid system (ECS) was discovered, a complex network of signaling pathways responsible for physiological homeostasis. Two key components of the ECS, cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2), were identified as the molecular targets of the phytocannabinoid Δ9-tetrahydrocannabinol (Δ9-THC). Restrictions on access to cannabis have eased worldwide, leading to a resurgence in interest in the therapeutic potential of cannabis. Much of the focus has been on the two major constituents, Δ9-THC and cannabidiol (CBD). Cannabis contains over 140 phytocannabinoids, although only a handful have been tested for pharmacological activity. Many of these minor cannabinoids potently modulate receptors, ionotropic channels, and enzymes associated with the ECS and show therapeutic potential individually or synergistically with other phytocannabinoids. The following review will focus on the pharmacological developments of the next generation of phytocannabinoid therapeutics.
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11
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Tashiro A, Bereiter DA. The effects of estrogen on temporomandibular joint pain as influenced by trigeminal caudalis neurons. J Oral Sci 2020; 62:150-155. [PMID: 32132330 DOI: 10.2334/josnusd.19-0405] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
The signs and symptoms of persistent temporomandibular joint (TMJ)/muscle disorder (TMJD) pain suggest the existence of a central neural dysfunction or a problem of pain amplification. The etiology of chronic TMJD is not known; however, female sex hormones have been identified as significant risk factors. Converging lines of evidence indicate that the junctional region between the trigeminal subnucleus caudalis (Vc) and the upper cervical spinal cord, termed the Vc/C1-2 region, is the primary site for the synaptic integration of sensory input from TMJ nociceptors. In this paper, the mechanisms behind the estrogen effects on the processing of nociceptive inputs by neurons in the Vc/C1-2 region reported by human and animal studies are reviewed. The Vc/C1-2 region has direct connections to endogenous pain and autonomic control pathways, which are modified by estrogen status and are suggested to be critical for somatomotor and autonomic reflex responses of TMJ-related sensory signals.
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Affiliation(s)
| | - David A Bereiter
- Department of Diagnostic and Biological Sciences, University of Minnesota School of Dentistry
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12
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Hsu HC, Hsieh CL, Lee KT, Lin YW. Electroacupuncture reduces fibromyalgia pain by downregulating the TRPV1-pERK signalling pathway in the mouse brain. Acupunct Med 2020; 38:101-108. [PMID: 31941349 DOI: 10.1136/acupmed-2017-011395] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Acupuncture has been clinically recommended as a method of pain relief by the World Health Organization and is widely used by medical doctors. Fibromyalgia (FM) pain has a complex physiological and psychological origin and can be pharmacologically treated with duloxetine, milnacipran and pregabalin. However, these drugs produce undesirable side effects, such as headaches, nausea and diarrhoea. Acupuncture may serve as an effective alternative treatment for pain relief with few side effects. AIMS We hypothesised that acupuncture would reduce FM pain by influencing transient receptor potential cation channel subfamily V member 1 (TRPV1) and the downstream phosphorylated extracellular signal-regulated kinases (pERK), which are located in the central thalamus, amygdala and cortex. METHODS A FM mouse model was established by injecting two doses of acid saline into 32 female C57/B6 mice. The mice were then assigned to different subgroups (n=8 each) and treated with electroacupuncture (EA) or EA sham control. TRPV1 and pERK expression levels were measured using Western blotting and immunohistochemistry. RESULTS Our results demonstrated that the expression of TRPV1 and pERK in the thalamus, amygdala and somatosensory cortex was normal in the control mice, but significantly increased in FM mice; these FM-induced changes in expression were attenuated by EA. CONCLUSION Our data suggest that EA can reverse the central sensitisation of the TRPV1-ERK signalling pathway in the mouse brain. Thus, our findings provide mechanistic evidence supporting the potential therapeutic efficacy of EA for treating FM pain.
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Affiliation(s)
- Hsin-Cheng Hsu
- College of Chinese Medicine, School of Post-Baccalaureate Chinese Medicine, China Medical University, Taichung, Taiwan
| | - Ching-Liang Hsieh
- College of Chinese Medicine, Graduate Institute of Acupuncture Science, China Medical University, Taichung, Taiwan.,College of Chinese Medicine, Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan
| | - Kun-Ta Lee
- College of Chinese Medicine, Graduate Institute of Acupuncture Science, China Medical University, Taichung, Taiwan
| | - Yi-Wen Lin
- College of Chinese Medicine, School of Post-Baccalaureate Chinese Medicine, China Medical University, Taichung, Taiwan.,College of Chinese Medicine, Graduate Institute of Acupuncture Science, China Medical University, Taichung, Taiwan.,Master's Program for Traditional Chinese Veterinary Medicine, Chi Institute of Traditional Chinese Veterinary Medicine, Reddick, Florida, USA.,Research Center for Chinese Medicine & Acupuncture, China Medical University, Taichung, Taiwan
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13
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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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14
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Pereira V, Goudet C. Emerging Trends in Pain Modulation by Metabotropic Glutamate Receptors. Front Mol Neurosci 2019; 11:464. [PMID: 30662395 PMCID: PMC6328474 DOI: 10.3389/fnmol.2018.00464] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 11/30/2018] [Indexed: 12/20/2022] Open
Abstract
Pain is an essential protective mechanism meant to prevent tissue damages in organisms. On the other hand, chronic or persistent pain caused, for example, by inflammation or nerve injury is long lasting and responsible for long-term disability in patients. Therefore, chronic pain and its management represents a major public health problem. Hence, it is critical to better understand chronic pain molecular mechanisms to develop innovative and efficient drugs. Over the past decades, accumulating evidence has demonstrated a pivotal role of glutamate in pain sensation and transmission, supporting glutamate receptors as promising potential targets for pain relieving drug development. Glutamate is the most abundant excitatory neurotransmitter in the brain. Once released into the synapse, glutamate acts through ionotropic glutamate receptors (iGluRs), which are ligand-gated ion channels triggering fast excitatory neurotransmission, and metabotropic glutamate receptors (mGluRs), which are G protein-coupled receptors modulating synaptic transmission. Eight mGluRs subtypes have been identified and are divided into three classes based on their sequence similarities and their pharmacological and biochemical properties. Of note, all mGluR subtypes (except mGlu6 receptor) are expressed within the nociceptive pathways where they modulate pain transmission. This review will address the role of mGluRs in acute and persistent pain processing and emerging pharmacotherapies for pain management.
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Affiliation(s)
- Vanessa Pereira
- IGF, CNRS, INSERM, Univ. de Montpellier, Montpellier, France
| | - Cyril Goudet
- IGF, CNRS, INSERM, Univ. de Montpellier, Montpellier, France
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15
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Ye Z, Zhang M, Ding N, Gao P, Hei Y, Wang Y, Gao W, Ye Q. Antinociceptive effects of dezocine on complete Freund's adjuvant-induced inflammatory pain in rats. Exp Ther Med 2018; 15:5469-5474. [PMID: 29904426 DOI: 10.3892/etm.2018.6110] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Accepted: 11/29/2017] [Indexed: 11/05/2022] Open
Abstract
Inflammatory pain is known to severely impact the life quality of patients. Notably, dezocine is widely used for the treatment of pain. Therefore, the current study aimed to examine the effects of dezocine on a complete Freund's adjuvant (CFA)-induced inflammatory pain model in rats and to investigate the possible underlying molecular mechanisms. Rats were randomly divided into three groups, including the control, CFA and dezocine+CFA groups, and then subcutaneously injected with 100 µl saline, subcutaneously injected with 100 µl CFA or pretreated with 1 ml dezocine (0.4 µg/kg) at 30 min before CFA injection in the plantar surface of right hind paw, respectively. The paw withdrawal threshold (PWT) and paw withdrawal latency (PWL) were measured with a dynamic plantar esthesiometer at 1 day before and 6 h after CFA injection. The ipsilateral lumbar spinal cords of all the rats were harvested for detecting the expression profiles of phosphorylated (p)-p65, p-extracellular signal-regulated kinase 1/2 (p-ERK1/2), cyclooxygenase-2 (COX-2), interleukin (IL)-1β and tumor necrosis factor (TNF)-α by western blot analysis and/or reverse transcription-quantitative polymerase chain reaction. In addition, prostaglandin E2 (PGE2) expression was determined by enzyme-linked immunosorbent assay. Compared with the control group, CFA-induced peripheral inflammation downregulated the PWT and PWL values of rats, which were significantly alleviated by dezocine treatment. Furthermore, the protein levels of p-p65, p-ERK1/2, COX-2, PGE2, IL-1β and TNF-α were significantly upregulated following CFA injection, while they were suppressed by dezocine pretreatment. In conclusion, the analgesic effect of dezocine on inflammatory pain induced by CFA may be associated with the inhibition of the spinal ERK1/2-COX-2 pathway.
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Affiliation(s)
- Zhenhai Ye
- Department of Anesthesiology, Ningxia People's Hospital, Yinchuan, Ningxia 750002, P.R. China.,Department of Anesthesiology, First Affiliated Hospital of Northwest University for Nationalities, Yinchuan, Ningxia 750002, P.R. China
| | - Maoxian Zhang
- Department of Anesthesiology, Ningxia People's Hospital, Yinchuan, Ningxia 750002, P.R. China.,Department of Anesthesiology, First Affiliated Hospital of Northwest University for Nationalities, Yinchuan, Ningxia 750002, P.R. China
| | - Ning Ding
- Department of Anesthesiology, Ningxia People's Hospital, Yinchuan, Ningxia 750002, P.R. China.,Department of Anesthesiology, First Affiliated Hospital of Northwest University for Nationalities, Yinchuan, Ningxia 750002, P.R. China
| | - Peng Gao
- Department of Anesthesiology, Ningxia People's Hospital, Yinchuan, Ningxia 750002, P.R. China.,Department of Anesthesiology, First Affiliated Hospital of Northwest University for Nationalities, Yinchuan, Ningxia 750002, P.R. China
| | - Yunpeng Hei
- Department of Anesthesiology, Ningxia People's Hospital, Yinchuan, Ningxia 750002, P.R. China.,Department of Anesthesiology, First Affiliated Hospital of Northwest University for Nationalities, Yinchuan, Ningxia 750002, P.R. China
| | - Yun Wang
- Department of Anesthesiology, Ningxia People's Hospital, Yinchuan, Ningxia 750002, P.R. China.,Department of Anesthesiology, First Affiliated Hospital of Northwest University for Nationalities, Yinchuan, Ningxia 750002, P.R. China
| | - Wei Gao
- Department of Anesthesiology, Ningxia People's Hospital, Yinchuan, Ningxia 750002, P.R. China.,Department of Anesthesiology, First Affiliated Hospital of Northwest University for Nationalities, Yinchuan, Ningxia 750002, P.R. China
| | - Qingshan Ye
- Department of Anesthesiology, Ningxia People's Hospital, Yinchuan, Ningxia 750002, P.R. China.,Department of Anesthesiology, First Affiliated Hospital of Northwest University for Nationalities, Yinchuan, Ningxia 750002, P.R. China
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16
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Zhang L, Yin JB, Hu W, Zhao WJ, Fan QR, Qiu ZC, He MJ, Ding T, Sun Y, Kaye AD, Wang ER. Analgesic Effects of Duloxetine on Formalin-Induced Hyperalgesia and Its Underlying Mechanisms in the CeA. Front Pharmacol 2018; 9:317. [PMID: 29692727 PMCID: PMC5902556 DOI: 10.3389/fphar.2018.00317] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 03/20/2018] [Indexed: 12/17/2022] Open
Abstract
In rodents, the amygdala has been proposed to serve as a key center for the nociceptive perception. Previous studies have shown that extracellular signal-regulated kinase (ERK) signaling cascade in the central nucleus of amygdala (CeA) played a functional role in inflammation-induced peripheral hypersensitivity. Duloxetine (DUL), a serotonin and noradrenaline reuptake inhibitor, produced analgesia on formalin-induced spontaneous pain behaviors. However, it is still unclear whether single DUL pretreatment influences formalin-induced hypersensitivity and what is the underlying mechanism. In the current study, we revealed that systemic pretreatment with DUL not only dose-dependently suppressed the spontaneous pain behaviors, but also relieved mechanical and thermal hypersensitivity induced by formalin hindpaw injection. Consistent with the analgesic effects of DUL on the pain behaviors, the expressions of Fos and pERK that were used to check the neuronal activities in the spinal cord and CeA were also dose-dependently reduced following DUL pretreatment. Meanwhile, no emotional aversive behaviors were observed at 24 h after formalin injection. The concentration of 5-HT in the CeA was correlated with the dose of DUL in a positive manner at 24 h after formalin injection. Direct injecting 5-HT into the CeA suppressed both the spontaneous pain behaviors and hyperalgesia induced by formalin injection. However, DUL did not have protective effects on the formalin-induced edema of hindpaw. In sum, the activation of CeA neurons may account for the transition from acute pain to long-term hyperalgesia after formalin injection. DUL may produce potent analgesic effects on the hyperalgesia and decrease the expressions of p-ERK through increasing the concentration of serotonin in the CeA.
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Affiliation(s)
- Lie Zhang
- Department of Neurosurgery, The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Jun-Bin Yin
- Department of Neurosurgery, The First Affiliated Hospital of Chengdu Medical College, Chengdu, China.,Department of Neurology, The 456th Hospital of PLA, Jinan, China.,Department of Human Anatomy, The Fourth Military Medical University, Xi'an, China
| | - Wei Hu
- Department of Neurosurgery, The First Affiliated Hospital of Chengdu Medical College, Chengdu, China.,Department of Human Anatomy, The Fourth Military Medical University, Xi'an, China
| | - Wen-Jun Zhao
- Department of Human Anatomy, The Fourth Military Medical University, Xi'an, China
| | - Qing-Rong Fan
- Department of Neurosurgery, The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Zhi-Chun Qiu
- Department of Neurosurgery, The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Ming-Jie He
- Department of Neurosurgery, The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Tan Ding
- Department of Orthopedics, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Yan Sun
- Cadet Bridge, The Fourth Military Medical University, Xi'an, China
| | - Alan D Kaye
- Departments of Anesthesiology and Pharmacology, Louisiana State University School of Medicine, New Orleans, LA, United States
| | - En-Ren Wang
- Department of Neurosurgery, The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
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17
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Spinal intracellular metabotropic glutamate receptor 5 (mGluR5) contributes to pain and c-fos expression in a rat model of inflammatory pain. Pain 2017; 158:705-716. [PMID: 28030475 DOI: 10.1097/j.pain.0000000000000823] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Metabotropic glutamate receptor 5 (mGluR5) is an excitatory G-protein-coupled receptor (GPCR) present in the spinal cord dorsal horn (SCDH) where it has a well-established role in pain. In addition to its traditional location on the cytoplasmic membrane, recent evidence shows that these receptors are present intracellularly on the nuclear membrane in the spinal cord dorsal horn and are implicated in neuropathic pain. Nuclear mGluR5 is a functional receptor that binds glutamate entering the cell through the neuronal glutamate transporter (GT) EAAT3 and activates transcription factor c-fos, whereas plasma membrane mGluR5 is responsible for c-jun activation. Here, we extend these findings to a model of inflammatory pain using complete Freund's adjuvant (CFA) and show that nuclear mGluR5 is also upregulated in the spinal cord dorsal horn following inflammation. We also show that pretreatment with an excitatory amino acid transporter (EAAT) inhibitor attenuates pain and decreases Fos, but not Jun, expression in complete Freund's adjuvant rats. In contrast, selective glial glutamate transporter inhibitors are pronociceptive and increase spinal glutamate concentrations. Additionally, we found that permeable mGluR5 antagonists are more effective at attenuating pain and Fos expression than nonpermeable group I mGluR antagonists. Taken together, these results suggest that under inflammatory conditions, intracellular mGluR5 is actively involved in the relay of nociceptive information in the spinal cord.
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18
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Zhou W, Chen Y, Zhang X. Astragaloside IV Alleviates Lipopolysaccharide-Induced Acute Kidney Injury Through Down-Regulating Cytokines, CCR5 and p-ERK, and Elevating Anti-Oxidative Ability. Med Sci Monit 2017; 23:1413-1420. [PMID: 28328867 PMCID: PMC5374805 DOI: 10.12659/msm.899618] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Background Astragaloside IV (AS-IV) has been shown to prevent ischemia-induced acute kidney injury (AKI) in rat models of ischemia and reperfusion. However, the effects of AS-IV on AKI during sepsis and endotoxinemia is unclear. The current study aimed to investigate the effects and molecular mechanisms of AS-IV on lipopolysaccharide (LPS)-induced AKI. Material/Methods Adult male CD-1 mice were randomly assigned into 6 groups (n=8/group): control group: mice were intraperitoneally (i.p.) injected with normal saline; LPS group (10 mg/kg, i.p.); low-dose AS-IV (25 mg/kg; gavage for 7 days) + LPS (i.p., 1 hour after last gavage) group; medial-dose AS-IV (50 mg/kg) + LPS group; high-dose AS-IV (100 mg/kg) + LPS group; high-dose AS-IV alone (100 mg/kg; gavage for 7 days) group. Blood samples were collected at 24 hours after LPS injection, and plasma uric acid and BUN were measured with colorimetric detection kits. The concentration of plasma tumor necrosis factor (TNF)-α and interleukin 1β, renal p-extracellular signal-regulated kinases, and urinary albumin were evaluated by ELISA. The expression of CCR5 in renal tissue was evaluated by PCR and Western blotting. Concentrations of glutathione (GSH) and reactive oxygen species (ROS) in renal tissue were also measured. Results AS-IV decreased LPS-stimulated production of blood TNF-α and IL-6, LPS-induced the expression of CCR5, and activation of ERK in the kidneys in a rodent model of endotoxinemia. AS-IV attenuated LPS-caused decreased GSH and increased ROS. It also attenuated LPS-induced increases in plasma uric acid, BUN, and urinary albumin. Conclusions AS-IV protects against AKI during bacterial endotoxinemia by attenuating expression of cytokines, CCR5, and p-ERK, and elevating anti-oxidative ability.
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Affiliation(s)
- Wei Zhou
- Department of Emergency, South Campus, Ren Ji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China (mainland)
| | - Yi Chen
- Department of Emergency, South Campus, Ren Ji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China (mainland)
| | - Xingyu Zhang
- Department of Emergency, South Campus, Ren Ji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China (mainland)
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19
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Huang YJ, Lee KH, Grau JW. Complete spinal cord injury (SCI) transforms how brain derived neurotrophic factor (BDNF) affects nociceptive sensitization. Exp Neurol 2017; 288:38-50. [PMID: 27818188 DOI: 10.1016/j.expneurol.2016.11.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 10/25/2016] [Accepted: 11/01/2016] [Indexed: 11/17/2022]
Abstract
Noxious stimulation can induce a lasting increase in neural excitability within the spinal cord (central sensitization) that can promote pain and disrupt adaptive function (maladaptive plasticity). Brain-derived neurotrophic factor (BDNF) is known to regulate the development of plasticity and has been shown to impact the development of spinally-mediated central sensitization. The latter effect has been linked to an alteration in GABA-dependent inhibition. Prior studies have shown that, in spinally transected rats, exposure to regular (fixed spaced) stimulation can counter the development of maladaptive plasticity and have linked this effect to an up-regulation of BDNF. Here it is shown that application of the irritant capsaicin to one hind paw induces enhanced mechanical reactivity (EMR) after spinal cord injury (SCI) and that the induction of this effect is blocked by pretreatment with fixed spaced shock. This protective effect was eliminated if rats were pretreated with the BDNF sequestering antibody TrkB-IgG. Intrathecal (i.t.) application of BDNF prevented, but did not reverse, capsaicin-induced EMR. BDNF also attenuated cellular indices (ERK and pERK expression) of central sensitization after SCI. In uninjured rats, i.t. BDNF enhanced, rather than attenuated, capsaicin-induced EMR and ERK/pERK expression. These opposing effects were related to a transformation in GABA function. In uninjured rats, BDNF reduced membrane-bound KCC2 and the inhibitory effect of the GABAA agonist muscimol. After SCI, BDNF increased KCC2 expression, which would help restore GABAergic inhibition. The results suggest that SCI transforms how BDNF affects GABA function and imply that the clinical usefulness of BDNF will depend upon the extent of fiber sparing.
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Affiliation(s)
- Yung-Jen Huang
- Behavioral and Cellular Neuroscience, Department of Psychology, Texas A&M University, College Station, TX 77843, USA.
| | - Kuan H Lee
- Center for Pain Research, Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - James W Grau
- Behavioral and Cellular Neuroscience, Department of Psychology, Texas A&M University, College Station, TX 77843, USA
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20
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Bilateral increases in ERK activation at the spinomedullary junction region by acute masseter muscle injury during temporomandibular joint inflammation in the rats. Exp Brain Res 2016; 235:913-921. [PMID: 27933357 DOI: 10.1007/s00221-016-4852-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 11/30/2016] [Indexed: 12/20/2022]
Abstract
We determined the role of persistent monoarthritis of temporomandibular joint region (TMJ) on bilateral masseter muscle (MM) nociception in male rats using orofacial nocifensive behaviors, phosphorylated extracellular signal-regulated kinase and Fos induction at the trigeminal subnucleus caudalis/upper cervical spinal cord (Vc/C2) region in response to formalin injection to the MM region. TMJ inflammation was induced by local injection of CFA into the left TMJ region. Orofacial nocifensive behaviors evoked by formalin injection ipsilateral or contralateral to the TMJ inflammation appeared to be increased at 1-14 days or at 1, 10 and 14 days after induction of TMJ inflammation, respectively, while increases in behavioral duration were seen mainly in the late phase rather than the early phase. The number of pERK positive cells was investigated in superficial laminae at the Vc/C2 region at 3, 10, 20, 60 and 80 min after MM stimulation with formalin at 14 days after TMJ inflammation. TMJ-inflamed rats displayed greater responses of pERK expression by the ipsilateral MM stimulation at 3-60 min, while contralateral MM stimulation increased pERK expression at 3, 10 and 20 min compared to non-CFA rats. Fos expression by MM stimulation was increased at 14 days after induction of TMJ inflammation regardless of the affected side. These findings showed that persistent TMJ inflammation for 10 and 14 days is sufficient to enhance MM nociception indicated by behaviors and neural responses in superficial laminae at the Vc/C2 region.
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21
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Chen Y, Jiang S, Liu Y, Xiong J, Liang J, Ji W. Role of ERK1/2 activation on itch sensation induced by bradykinin B1 activation in inflamed skin. Exp Ther Med 2016; 12:627-632. [PMID: 27446253 PMCID: PMC4950635 DOI: 10.3892/etm.2016.3426] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 04/11/2016] [Indexed: 12/26/2022] Open
Abstract
It has previously been demonstrated that bradykinin receptor B1 (B1R) agonists evoke an itch-related scratching response in inflamed skin via the B1 receptor; however, the mechanisms responsible for this abnormal itch sensation remain unclear. Therefore, the present study utilized a complete Freund's adjuvant (CFA)-induced mouse model of inflammation to elucidate the mechanisms responsible. Over a period of 30 min, scratching behavior was quantified by the number of hind limb scratches of the area surrounding the drug injection site on the neck. Furthermore, western blot analysis was used to investigate the potential role of extracellular signal-regulated kinase (ERK) 1/2 signaling as a mediator of itch in CFA-treated mice. The results demonstrated that CFA-induced inflammation at the back of the neck is associated with sustained enhancement of ERK1/2 activation in the spinal cord. Moreover, B1R agonist treatment resulted in increased expression of phosphorylated ERK1/2 in the spinal cord, which peaked at 45 min. Consistent with these findings, inhibition of either mitogen-activated protein/ERK kinase or ERK1/2, as well as inhibition of ERK1/2 activation following inflammation, attenuated B1 receptor-mediated scratching responses to a greater extent, as compared with control mice. Collectively, the results of the present study indicated that enhanced and persistent ERK1/2 activation in the spinal cord may be required to induce a scratching response to B1R agonists following CFA-induced inflammation.
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Affiliation(s)
- Yuanzhen Chen
- Postgraduate Institute, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China; Department of Anesthesiology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong 510080, P.R. China
| | - Shuyan Jiang
- Postgraduate Institute, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China; Division of Anesthesiology, Department of Cardiovascular Surgery, Guangdong Institute of Cardiovascular Diseases, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong 510080, P.R. China
| | - Yuying Liu
- Postgraduate Institute, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China; Department of Anesthesiology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong 510080, P.R. China
| | - Jialing Xiong
- Postgraduate Institute, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China; Division of Anesthesiology, Department of Cardiovascular Surgery, Guangdong Institute of Cardiovascular Diseases, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong 510080, P.R. China
| | - Jiexian Liang
- Postgraduate Institute, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China; Division of Anesthesiology, Department of Cardiovascular Surgery, Guangdong Institute of Cardiovascular Diseases, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong 510080, P.R. China
| | - Wenjin Ji
- Department of Anesthesiology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong 510080, P.R. China
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22
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Wang D, Wang P, Jiang J, Lv Q, Zeng X, Hong Y. Activation of Mas Oncogene-Related G Protein–Coupled Receptors Inhibits Neurochemical Alterations in the Spinal Dorsal Horn and Dorsal Root Ganglia Associated with Inflammatory Pain in Rats. J Pharmacol Exp Ther 2015; 354:431-439. [DOI: 10.1124/jpet.115.225672] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
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23
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Gris G, Cobos EJ, Zamanillo D, Portillo-Salido E. Sigma-1 receptor and inflammatory pain. Inflamm Res 2015; 64:377-81. [PMID: 25902777 DOI: 10.1007/s00011-015-0819-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 03/23/2015] [Accepted: 04/08/2015] [Indexed: 01/28/2023] Open
Abstract
INTRODUCTION The sigma-1 receptor (Sig-1R) is a unique ligand-regulated molecular chaperone that interacts with several protein targets such as G protein-coupled receptors and ion channels to modulate their activity. Sig-1R is located in areas of the central and peripheral nervous system that are key to pain control. Previous preclinical studies have suggested a potential therapeutic use of Sig-1R antagonists for the management of neuropathic pain. DISCUSSION Recent studies using pharmacological and genetic tools have explored the role of Sig-1R in inflammatory pain conditions. Mice lacking the Sig-1R have shown different patterns of phenotypic responses to inflammatory injury. Systemic or peripheral administration of several Sig-1R antagonists, including the selective Sig-1R antagonist S1RA, inhibited both mechanical and thermal hypersensitivity in several preclinical models of inflammatory pain. These recent studies are summarized in the present commentary. CONCLUSION Central and peripheral pharmacological blockade of Sig-1R could be an effective option to treat inflammatory pain.
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Affiliation(s)
- Georgia Gris
- Drug Discovery and Preclinical Development, ESTEVE, Baldiri Reixach, 4-8, 08028, Barcelona, Spain
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24
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Tashiro A, Nishida Y, Bereiter DA. Local group I mGluR antagonists reduce TMJ-evoked activity of trigeminal subnucleus caudalis neurons in female rats. Neuroscience 2015; 299:125-33. [PMID: 25934040 DOI: 10.1016/j.neuroscience.2015.04.051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 04/17/2015] [Accepted: 04/21/2015] [Indexed: 10/23/2022]
Abstract
Group I metabotropic glutamate receptors (mGluR1 and mGluR5) are functionally linked to estrogen receptors and play a key role in the plasticity of central neurons. Estrogen status strongly influences sensory input from the temporomandibular joint (TMJ) to neurons at the spinomedullary (Vc/C1-2) region. This study tested the hypothesis that TMJ input to trigeminal subnucleus caudalis/upper cervical cord (Vc/C1-2) neurons involved group I mGluR activation and depended on estrogen status. TMJ-responsive neurons were recorded in superficial laminae at the Vc/C1-2 region in ovariectomized (OvX) female rats treated with low-dose estradiol (2 μg/day, LE) or high-dose estradiol (20 μg/day, HE) for 2 days. TMJ-responsive units were activated by adenosine triphosphate (ATP, 1mM) injected into the joint space. Receptor antagonists selective for mGluR1 (CPCCOEt) or mGluR5 (MPEP) were applied topically to the Vc/C1-2 surface at the site of recording 10 min prior to the intra-TMJ ATP stimulus. In HE rats, CPCCOEt (50 and 500 μM) markedly reduced ATP-evoked unit activity. By contrast, in LE rats, a small but significant increase in neural activity was seen after 50 μM CPCCOEt, while 500 μM caused a large reduction in activity that was similar in magnitude as that seen in HE rats. Local application of MPEP produced a significant inhibition of TMJ-evoked unit activity independent of estrogen status. Neither mGluR1 nor mGluR5 antagonism altered the spontaneous activity of TMJ units in HE or LE rats. High-dose MPEP caused a small reduction in the size of the convergent cutaneous receptive field in HE rats, while CPCCOEt had no effect. These data suggest that group I mGluRs play a key role in sensory integration of TMJ nociceptive input to the Vc/C1-2 region and are largely independent of estrogen status.
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Affiliation(s)
- A Tashiro
- Department of Physiology, National Defense Medical College, Namiki 3-2, Tokorozawa City, Saitama 359-8513, Japan.
| | - Y Nishida
- Department of Physiology, National Defense Medical College, Namiki 3-2, Tokorozawa City, Saitama 359-8513, Japan
| | - D A Bereiter
- Department of Diagnostic and Biological Sciences, University of Minnesota School of Dentistry, Moos Tower 18-214, 515 Delaware Street SE, Minneapolis, MN 55455, USA
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Cho SY, Ki HG, Kim JM, Oh JM, Yang JH, Kim WM, Lee HG, Yoon MH, Choi JI. Expression of the spinal 5-HT7 receptor and p-ERK pathway in the carrageenan inflammatory pain of rats. Korean J Anesthesiol 2015; 68:170-4. [PMID: 25844136 PMCID: PMC4384405 DOI: 10.4097/kjae.2015.68.2.170] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 08/21/2014] [Accepted: 08/22/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Although the inhibitory role of the 5-hydroxytrypatmine receptor 7(5-HT7R) on nociceptive processing is generally recognized, an excitatory effect associated with a reduced 5-HT7R expression has also been observed in the nerve injury model. In the carrageenan model, no significant effect is produced by the 5-HT7R activation, but the change in 5-HT7R expression has not been examined. Lesioning of the spinal serotonergic pathway enhances allodynia in the carrageenan model, but it also relieves several other pain states, including in the formalin model. While lesioning suppresses the activation of the extracellular signal-regulated kinase (ERK) of the spinal cord in the formalin model, its role in the carrageenan model has not been reported. METHODS Following intraplantar injections of carrageenan, the spinal 5-HT7R expression was examined using Western blotting in male Sprague-Dawley rats. The effect of serotonergic pathway lesioning with intrathecal 5,7-dihydroxytryptamine (5,7-DHT) on the expression of the phospho-ERK was measured. RESULTS The expression of the 5-HT7R in the carrageenan model was not significantly different from that of naive animals. The expression of the spinal p-ERK in the carrageenan model was significantly increased, but returned to the level of a naive rat 1 hour after the carrageenan injection. However, it remained significantly higher 1 hour after the injection in the animals treated with 5,7-DHT than in the naive and control rats. CONCLUSIONS The expression of the spinal 5-HT7R is not altered by peripheral inflammation with carrageenan, suggesting that the lack of antinociceptive effect of the 5-HT7R activation is partly attributable to the absence of changes in the expression of the 5-HT7R in the spinal cord. The extended increase of the spinal p-ERK might be related to the enhanced pain behavior in the animals with lesions of the spinal serotonergic pathway in the carrageenan model.
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Affiliation(s)
- Soo Young Cho
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School and Hospital, Gwangju, Korea
| | - Hyoung Gon Ki
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School and Hospital, Gwangju, Korea
| | - Joung Min Kim
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School and Hospital, Gwangju, Korea
| | - Jin Myung Oh
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School and Hospital, Gwangju, Korea
| | - Ji Hoon Yang
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School and Hospital, Gwangju, Korea
| | - Woong Mo Kim
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School and Hospital, Gwangju, Korea
| | - Hyung Gon Lee
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School and Hospital, Gwangju, Korea
| | - Myung Ha Yoon
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School and Hospital, Gwangju, Korea
| | - Jeong Il Choi
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School and Hospital, Gwangju, Korea
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Kolber BJ. mGluRs Head to Toe in Pain. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 131:281-324. [DOI: 10.1016/bs.pmbts.2014.12.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Fang JQ, Fang JF, Liang Y, Du JY. Electroacupuncture mediates extracellular signal-regulated kinase 1/2 pathways in the spinal cord of rats with inflammatory pain. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2014; 14:285. [PMID: 25091495 PMCID: PMC4131029 DOI: 10.1186/1472-6882-14-285] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 06/25/2014] [Indexed: 12/31/2022]
Abstract
Background Activation of extracellular signal-regulated kinase1/2 (ERK1/2) in dorsal horn of the spinal cord by peripheral inflammation is contributed to inflammatory pain hypersensitivity. Although electroacupuncture (EA) has been widely used to alleviate various kinds of pain, the underlying mechanism of EA analgesia requires further investigation. This study investigated the relationship between EA-induced analgesia and ERK signaling involved in pain hypersensitivity. Methods The rats were randomly divided into control, model, EA and sham EA groups. Inflammatory pain model was induced by injecting of 100 μl Complete Freund’s adjuvant (CFA) into the plantar surface of a hind paw. Rats in the EA group were treatment with EA (constant aquare wave, 2 Hz and 100 Hz alternating frequencies, intensities ranging from 1-2 mA) at 5.5 h, 24.5 h and 48.5 h. Paw withdrawal thresholds (PWTs) were measured before modeling and at 5 h, 6 h, 25 h and 49 h after CFA injection. Rats were killed and ipsilateral side of the lumbar spinal cords were harvested for detecting the expressions of p-ERK1/2, Elk1, COX-2, NK-1 and CREB by immunohistochemistry, real-time PCR, western blot analysis and EMSA. Finally, the analgesic effect of EA plus U0126, a MEK (ERK kinase) inhibitor, on CFA rats was examined. Results Inflammatory pain was induced in rats by hindpaw injection of CFA and significantly increased phospho-ERK1/2 positive cells and protein levels of p-ERK1/2 in the ipsilateral spinal cord dorsal horn (SCDH). CFA up-regulated of cyclooxygenase-2 (COX-2) mRNA and protein expression at 6 h after injection and neurokinin-1 receptor (NK-1) expression at 49 h post-injection, in the SCDH. EA, applied to Zusanli (ST36) and Kunlun (BL60), remarkably increased the pain thresholds of CFA injected rats, significantly suppressed ERK1/2 activation and COX-2 protein expression after a single treatment, and decreased NK-1 mRNA and protein expression at 49 h. EA decreased the DNA binding activity of cAMP response element binding protein (CREB), a downstream transcription factor of ERK1/2, at 49 h after CFA injection. Moreover, EA and U0126 synergistically inhibited CFA-induced allodynia. Conclusions The present study suggests that EA produces analgesic effect by preventing the activation of ERK1/2-COX-2 pathway and ERK1/2-CREB-NK-1 pathway in CFA rats.
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Worsley MA, Allen CE, Billinton A, King AE, Boissonade FM. Chronic tooth pulp inflammation induces persistent expression of phosphorylated ERK (pERK) and phosphorylated p38 (pp38) in trigeminal subnucleus caudalis. Neuroscience 2014; 269:318-30. [PMID: 24709040 PMCID: PMC4030309 DOI: 10.1016/j.neuroscience.2014.03.056] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 03/13/2014] [Accepted: 03/27/2014] [Indexed: 12/29/2022]
Abstract
Chronic inflammation of tooth pulp activates pERK and pp38 in the trigeminal nucleus Activation is persistent and bilateral, and further increased by acute stimulation This altered signaling may be relevant in the development of chronic pulpitic pain pERK and pp38 are more sensitive markers of central change than Fos expression Sequential activation in different cell types may be linked to pain progression
Background Extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase are transiently phosphorylated (activated) in the spinal cord and trigeminal nucleus by acute noxious stimuli. Acute stimulation of dental pulp induces short-lived ERK activation in trigeminal subnucleus caudalis (Vc), and p38 inhibition attenuates short-term sensitization in Vc induced by acute pulpal stimulation. We have developed a model to study central changes following chronic inflammation of dental pulp that induces long-term sensitization. Here, we examine the effects of chronic inflammation and acute stimulation on the expression of phosphorylated ERK (pERK), phosphorylated p38 (pp38) and Fos in Vc. Results Chronic inflammation alone induced bilateral expression of pERK and pp38 in Vc, but did not induce Fos expression. Stimulation of both non-inflamed and inflamed pulps significantly increased pERK and pp38 bilaterally; expression was greatest in inflamed, stimulated animals, and was similar following 10-min and 60-min stimulation. Stimulation for 60 min, but not 10 min, induced Fos in ipsilateral Vc; Fos expression was significantly greater in inflamed, stimulated animals. pERK was present in both neurons and astrocytes; pp38 was present in neurons and other non-neuronal, non-astrocytic cell types. Conclusions This study provides the first demonstration that chronic inflammation of tooth pulp induces persistent bilateral activation of ERK and p38 within Vc, and that this activation is further increased by acute stimulation. This altered activity in intracellular signaling is likely to be linked to the sensitization that is seen in our animal model and in patients with pulpitis. Our data indicate that pERK and pp38 are more accurate markers of central change than Fos expression. In our model, localization of pERK and pp38 within specific cell types differs from that seen following acute stimulation. This may indicate specific roles for different cell types in the induction and maintenance of pulpitic and other types of pain.
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Affiliation(s)
- M A Worsley
- Unit of Oral & Maxillofacial Medicine & Surgery, School of Clinical Dentistry, University of Sheffield, Claremont Crescent, Sheffield S10 2TA, UK
| | - C E Allen
- Unit of Oral & Maxillofacial Medicine & Surgery, School of Clinical Dentistry, University of Sheffield, Claremont Crescent, Sheffield S10 2TA, UK
| | | | - A E King
- School of Biomedical Sciences, University of Leeds, UK
| | - F M Boissonade
- Unit of Oral & Maxillofacial Medicine & Surgery, School of Clinical Dentistry, University of Sheffield, Claremont Crescent, Sheffield S10 2TA, UK.
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Zhang X, Zhang H, Shao H, Xue Q, Yu B. ERK MAP kinase activation in spinal cord regulates phosphorylation of Cdk5 at serine 159 and contributes to peripheral inflammation induced pain/hypersensitivity. PLoS One 2014; 9:e87788. [PMID: 24498195 PMCID: PMC3909239 DOI: 10.1371/journal.pone.0087788] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 01/02/2014] [Indexed: 11/18/2022] Open
Abstract
Cyclin-dependent kinase 5 is a proline-directed serine/threonine kinase and its activity participates in the regulation of nociceptive signaling. Like binding with the activators (P35 or P25), the phosphorylation of Cdk5 plays a critical role in Cdk5 activation. However, it is still unclear whether Cdk5 phosphorylation (p-Cdk5) contributes to pain hyperalgesia. The aim of our current study was to identify the roles of p-Cdk5 and its upstream regulator in response to peripheral inflammation. Complete Freund's adjuvant (CFA) injection induced acute peripheral inflammation and heat hyperalgesia, which was accompanied by sustained increases in phospho-ERK1/2 (p-ERK1/2) and phospho-Cdk5S159 (p-Cdk5S159) in the spinal cord dorsal horn (SCDH). CFA-induced p-ERK primarily colocalized with p-Cdk5S159 in superficial dorsal horn neurons. Levels in p-ERK and p-Cdk5 were also increased in the 2nd phase of hyperalgesia induced by formalin injection, which can produce acute and tonic inflammatory pain. MAP kinase kinase inhibitor U0126 intrathecal delivery significantly suppressed the elevation of p-Cdk5S159, Cdk5 activity and pain response behavior (Heat hyperalgesia, Spontaneous flinches) induced by CFA or formalin injection. Cdk5 inhibitor roscovitine intrathecal administration also suppressed CFA-induced heat hyperalgesia and Cdk5 phosphorylation, but did not attenuate ERK activation. All these findings suggested that p-Cdk5S159 regulated by ERK pathway activity may be a critical mechanism involved in the activation of Cdk5 in nociceptive spinal neurons contributes to peripheral inflammatory pain hypersensitivity.
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Affiliation(s)
- Xiaoqin Zhang
- Department of Anesthesia, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Honghai Zhang
- Department of Anesthesia, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P.R. China
- Department of Anesthesia, Hangzhou First People's Hospital, Nanjing Medical University, Zhejiang, P.R. China
| | - Haijun Shao
- Department of Anesthesia, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Qingsheng Xue
- Department of Anesthesia, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Buwei Yu
- Department of Anesthesia, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P.R. China
- * E-mail:
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Effects of Acupuncture on 1-Chloro-2,4-dinitrochlorobenzene-Induced Atopic Dermatitis. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 2013:982095. [PMID: 23997805 PMCID: PMC3755411 DOI: 10.1155/2013/982095] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 07/03/2013] [Accepted: 07/05/2013] [Indexed: 11/18/2022]
Abstract
Though the effects of acupuncture in atopic dermatitis have been proven in clinical studies, its mechanism remains unclear. In this study, we investigate the effectiveness and mechanism of action for acupuncture treatment on the LI11 meridian point for treatment of allergic contact dermatitis. BALB/c mice received 1-chloro-2,4-dinitrobenzene (DNCB) application to induce skin inflammation. Acupuncture treatment on LI11 significantly inhibited cutaneous hyperplasia, serum IgE levels, and expression of proinflammatory cytokine (IL-4, IL-8, and TNF- α ) mRNA and NF- κ B, ERK1/2, JNK, and p38 proteins. Acupuncture treatment of local points also inhibited cutaneous hyperplasia and serum IgE levels; however, it was not effective in regulating proinflammatory cytokines and proteins. In addition, LI11 treatment is more effective at reducing serum IgE levels and pro-inflammatory cytokines and proteins than local point treatment. These results suggest that acupuncture treatment is effective in alleviating allergic contact dermatitis by reducing pro-inflammatory cytokines and proteins.
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Fang JF, Liang Y, Du JY, Fang JQ. Transcutaneous electrical nerve stimulation attenuates CFA-induced hyperalgesia and inhibits spinal ERK1/2-COX-2 pathway activation in rats. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 13:134. [PMID: 23768044 PMCID: PMC3689089 DOI: 10.1186/1472-6882-13-134] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Accepted: 06/11/2013] [Indexed: 11/16/2022]
Abstract
BACKGROUND Transcutaneous electrical nerve stimulation (TENS) is a non-pharmacologic treatment for pain relief. In previous animal studies, TENS effectively alleviated Complete Freund's Adjuvant (CFA)- or carrageenan-induced inflammatory pain. Although TENS is known to produce analgesia via opioid activation in the brain and at the spinal level, few reports have investigated the signal transduction pathways mediated by TENS. Prior studies have verified the importance of the activation of extracellular signal-regulated kinase (ERK) signal transduction pathway in the spinal cord dorsal horn (SCDH) in acute and persistent inflammatory pains. Here, by using CFA rat model, we tested the efficacy of TENS on inhibiting the expressions of p-ERK1/2 and of its downstream cyclooxygenase-2 (COX-2) and the level of prostaglandin E2 (PGE2) at spinal level. METHODS Rats were randomly divided into control, model and TENS groups, and injected subcutaneously with 100 μl CFA or saline in the plantar surface of right hind paw. Rats in the TENS group were treated with TENS (constant aquare wave, 2 Hz and 100 Hz alternating frequencies, intensities ranging from 1 to 2 mA, lasting for 30 min each time) at 5 h and 24 h after injection. Paw withdrawal thresholds (PWTs) were measured with dynamic plantar aesthesiometer at 3d before modeling and 5 h, 6 h, and 25 h after CFA injection. The ipsilateral sides of the lumbar spinal cord dosral horns were harvested for detecting the expressions of p-ERK1/2 and COX-2 by western blot analysis and qPCR, and PGE2 by ELISA. RESULTS CFA-induced periphery inflammation decreased PWTs and increased paw volume of rats. TENS treatment significantly alleviated mechanical hyperalgesia caused by CFA. However, no anti-inflammatory effect of TENS was observed. Expression of p-ERK1/2 protein and COX-2 mRNA was significantly up-regualted at 5 h and 6 h after CFA injection, while COX-2 and PGE2 protein level only increased at 6 h after modeling. Furthermore, the high expression of p-ERK1/2 and COX-2, and over-production of PGE2 induced by CFA, were suppressed by TENS administration. CONCLUSIONS TENS may be an effective therapy in controlling inflammatory pain induced by CFA. Its analgesic effect may be associated with the inhibition of activation of the spinal ERK1/2-COX-2 pathway.
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Affiliation(s)
- Jun-Fan Fang
- Department of Neurobiology & Acupuncture Research, the Third Clinical College, Zhejiang Chinese Medical University, Hangzhou, China
| | - Yi Liang
- Department of Neurobiology & Acupuncture Research, the Third Clinical College, Zhejiang Chinese Medical University, Hangzhou, China
| | - Jun-Ying Du
- Department of Neurobiology & Acupuncture Research, the Third Clinical College, Zhejiang Chinese Medical University, Hangzhou, China
| | - Jian-Qiao Fang
- Department of Neurobiology & Acupuncture Research, the Third Clinical College, Zhejiang Chinese Medical University, Hangzhou, China
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Kuwahata H, Komatsu T, Katsuyama S, Corasaniti MT, Bagetta G, Sakurada S, Sakurada T, Takahama K. Peripherally injected linalool and bergamot essential oil attenuate mechanical allodynia via inhibiting spinal ERK phosphorylation. Pharmacol Biochem Behav 2013; 103:735-41. [DOI: 10.1016/j.pbb.2012.11.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2012] [Revised: 10/29/2012] [Accepted: 11/03/2012] [Indexed: 10/27/2022]
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Metabotropic glutamate receptor 5 contributes to inflammatory tongue pain via extracellular signal-regulated kinase signaling in the trigeminal spinal subnucleus caudalis and upper cervical spinal cord. J Neuroinflammation 2012. [PMID: 23181395 PMCID: PMC3543209 DOI: 10.1186/1742-2094-9-258] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Background In the orofacial region, limited information is available concerning pathological tongue pain, such as inflammatory pain or neuropathic pain occurring in the tongue. Here, we tried for the first time to establish a novel animal model of inflammatory tongue pain in rats and to investigate the roles of metabotropic glutamate receptor 5 (mGluR5)-extracellular signal-regulated kinase (ERK) signaling in this process. Methods Complete Freund’s adjuvant (CFA) was submucosally injected into the tongue to induce the inflammatory pain phenotype that was confirmed by behavioral testing. Expression of phosphorylated ERK (pERK) and mGluR5 in the trigeminal subnucleus caudalis (Vc) and upper cervical spinal cord (C1-C2) were detected with immunohistochemical staining and Western blotting. pERK inhibitor, a selective mGluR5 antagonist or agonist was continuously administered for 7 days via an intrathecal (i.t.) route. Local inflammatory responses were verified by tongue histology. Results Submucosal injection of CFA into the tongue produced a long-lasting mechanical allodynia and heat hyperalgesia at the inflamed site, concomitant with an increase in the pERK immunoreactivity in the Vc and C1-C2. The distribution of pERK-IR cells was laminar specific, ipsilaterally dominant, somatotopically relevant, and rostrocaudally restricted. Western blot analysis also showed an enhanced activation of ERK in the Vc and C1-C2 following CFA injection. Continuous i.t. administration of the pERK inhibitor and a selective mGluR5 antagonist significantly depressed the mechanical allodynia and heat hyperalgesia in the CFA-injected tongue. In addition, the number of pERK-IR cells in ipsilateral Vc and C1-C2 was also decreased by both drugs. Moreover, continuous i.t. administration of a selective mGluR5 agonist induced mechanical allodynia in naive rats. Conclusions The present study constructed a new animal model of inflammatory tongue pain in rodents, and demonstrated pivotal roles of the mGluR5-pERK signaling in the development of mechanical and heat hypersensitivity that evolved in the inflamed tongue. This tongue-inflamed model might be useful for future studies to further elucidate molecular and cellular mechanisms of pathological tongue pain such as burning mouth syndrome.
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Hovelsø N, Sotty F, Montezinho LP, Pinheiro PS, Herrik KF, Mørk A. Therapeutic potential of metabotropic glutamate receptor modulators. Curr Neuropharmacol 2012; 10:12-48. [PMID: 22942876 PMCID: PMC3286844 DOI: 10.2174/157015912799362805] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2010] [Revised: 01/10/2011] [Accepted: 03/04/2011] [Indexed: 12/21/2022] Open
Abstract
Glutamate is the main excitatory neurotransmitter in the central nervous system (CNS) and is a major player in complex brain functions. Glutamatergic transmission is primarily mediated by ionotropic glutamate receptors, which include NMDA, AMPA and kainate receptors. However, glutamate exerts modulatory actions through a family of metabotropic G-protein-coupled glutamate receptors (mGluRs). Dysfunctions of glutamatergic neurotransmission have been implicated in the etiology of several diseases. Therefore, pharmacological modulation of ionotropic glutamate receptors has been widely investigated as a potential therapeutic strategy for the treatment of several disorders associated with glutamatergic dysfunction. However, blockade of ionotropic glutamate receptors might be accompanied by severe side effects due to their vital role in many important physiological functions. A different strategy aimed at pharmacologically interfering with mGluR function has recently gained interest. Many subtype selective agonists and antagonists have been identified and widely used in preclinical studies as an attempt to elucidate the role of specific mGluRs subtypes in glutamatergic transmission. These studies have allowed linkage between specific subtypes and various physiological functions and more importantly to pathological states. This article reviews the currently available knowledge regarding the therapeutic potential of targeting mGluRs in the treatment of several CNS disorders, including schizophrenia, addiction, major depressive disorder and anxiety, Fragile X Syndrome, Parkinson’s disease, Alzheimer’s disease and pain.
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Affiliation(s)
- N Hovelsø
- Department of Neurophysiology, H. Lundbeck A/S, Ottiliavej 9, 2500 Copenhagen-Valby, Denmark
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Anti-nociceptive effects of Tanshinone IIA (TIIA) in a rat model of complete Freund's adjuvant (CFA)-induced inflammatory pain. Brain Res Bull 2012; 88:581-8. [DOI: 10.1016/j.brainresbull.2012.06.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Accepted: 06/06/2012] [Indexed: 12/28/2022]
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Lee MJ, Jang M, Jung HS, Kim SH, Cho IH. Ethyl pyruvate attenuates formalin-induced inflammatory nociception by inhibiting neuronal ERK phosphorylation. Mol Pain 2012; 8:40. [PMID: 22640699 PMCID: PMC3472237 DOI: 10.1186/1744-8069-8-40] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Accepted: 05/10/2012] [Indexed: 12/28/2022] Open
Abstract
Background Ethyl pyruvate (EP) possesses anti-inflammatory activity. However, the potential anti-nociceptive value of EP for the treatment of the inflammatory nociception is largely unknown. We investigated whether EP could have any anti-nociceptive effect on inflammatory pain, after systemic administration of EP (10, 50, and 100 mg/kg, i.p.), 1 hour before formalin (5%, 50 μl) injection into the plantar surface of the hind paws of rats. Results EP significantly decreased formalin-induced nociceptive behavior during phase II, the magnitude of paw edema, and the activation of c-Fos in L4-L5 spinal dorsal horn. EP also attenuated the phosphorylation of extracellular signal-regulated kinase (ERK) in the neurons of L4-L5 spinal dorsal horn after formalin injection. Interestingly, the i.t. administration of PD98059, an ERK upstream kinase (MEK) inhibitor, completely blocked the formalin-induced inflammatory nociceptive responses. Conclusions These results demonstrate that EP may effectively inhibit formalin-induced inflammatory nociception via the inhibition of neuronal ERK phosphorylation in the spinal dorsal horn, indicating its therapeutic potential in suppressing acute inflammatory pain.
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Affiliation(s)
- Min Jung Lee
- Department of Anatomy, College of Oriental Medicine, and Institute of Oriental Medicine, Kyung Hee University, Seoul, 130-701, Republic of Korea
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Affiliation(s)
- Jelena Radulovic
- Department of Psychiatry and Behavioral Sciences, The Asher Center for Study and Treatment of Depressive Disorders, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
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Kim SJ, Kim JS, Choi IY, Kim DH, Kim MC, An HJ, Na HJ, Kim NH, Moon PD, Myung NY, Lee JY, Jeong HJ, Um JY, Shin TY, Kim HM, Hong SH. Anti-Inflammatory Activity ofSchizonepeta tenuifoliathrough the Inhibition of MAPK Phosphorylation in Mouse Peritoneal Macrophages. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2012; 36:1145-58. [DOI: 10.1142/s0192415x0800648x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Schizonepeta tenuifolia (ST) is a well-known herb to treat the cold and its associated headache. However, the anti-inflammatory mechanism of ST in mouse peritoneal macrophages is not clear. In this study, we demonstrated that ST inhibited lipopolysaccaride (LPS)-induced tumor necrosis factor (TNF)-α and interleukin (IL)-6 production. The maximal inhibition rate of TNF-α and IL-6 production by ST (2 mg/ml) was 48.01 ± 2.8% and 56.45 ± 2.8%, respectively. During the inflammatory process, cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS) were increased in mouse peritoneal macrophages. However, treated with ST decreased the protein level of COX-2 and iNOS, as well as the production of PGE2and NO in LPS-stimulated mouse peritoneal macrophages. In addition, ST inhibited the phosphorylation of MAPK. Taken together, the results of this study suggest an important molecular mechanism by which ST reduces inflammation, which may explain its beneficial effect in the regulation of inflammatory reactions.
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Affiliation(s)
- Su-Jin Kim
- College of Pharmacy, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea
- College of Oriental Medicine, Institute of Oriental Medicine, Kyung Hee University, 1 Hoegi-Dong, Dongdaemun-Gu, Seoul, 130-701, Republic of Korea
| | - Jung-Sun Kim
- College of Pharmacy, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea
| | - In-Young Choi
- College of Pharmacy, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea
| | - Dong-Hyun Kim
- College of Pharmacy, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea
| | - Min-Cheol Kim
- College of Pharmacy, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea
| | - Hyo-Jin An
- College of Oriental Medicine, Institute of Oriental Medicine, Kyung Hee University, 1 Hoegi-Dong, Dongdaemun-Gu, Seoul, 130-701, Republic of Korea
| | - Ho-Jeong Na
- College of Oriental Medicine, Institute of Oriental Medicine, Kyung Hee University, 1 Hoegi-Dong, Dongdaemun-Gu, Seoul, 130-701, Republic of Korea
| | - Na-Hyung Kim
- College of Oriental Medicine, Institute of Oriental Medicine, Kyung Hee University, 1 Hoegi-Dong, Dongdaemun-Gu, Seoul, 130-701, Republic of Korea
| | - Phil-Dong Moon
- Oriental Medical Science Center, College of Oriental Medicine, Kyung Hee University, 1 Hoegi-Dong, Dongdaemun-Gu, Seoul, 130-701, Republic of Korea
| | - Noh-Yil Myung
- Acupuncture and Meridian Science Research Center, Kyung Hee University, 1 Hoegi-Dong, Dongdaemun-Gu, Seoul, 130-701, Republic of Korea
| | - Ju-Young Lee
- Department of Herb Science, ShinSung College, Chungnam 343-861, Republic of Korea
| | - Hyun-Ja Jeong
- Biochip Research Center, Hoseo University, Asan, Chungnam, 336-795, Republic of Korea
| | - Jae-Young Um
- College of Oriental Medicine, Institute of Oriental Medicine, Kyung Hee University, 1 Hoegi-Dong, Dongdaemun-Gu, Seoul, 130-701, Republic of Korea
- Acupuncture and Meridian Science Research Center, Kyung Hee University, 1 Hoegi-Dong, Dongdaemun-Gu, Seoul, 130-701, Republic of Korea
| | - Tae-Yong Shin
- College of Pharmacy, Woosuk University, Jeonju, Republic of Korea
| | - Hyung-Min Kim
- College of Oriental Medicine, Institute of Oriental Medicine, Kyung Hee University, 1 Hoegi-Dong, Dongdaemun-Gu, Seoul, 130-701, Republic of Korea
| | - Seung-Heon Hong
- College of Pharmacy, Wonkwang University, Iksan, Jeonbuk, 570-749, Republic of Korea
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Price TJ, Melemedjian OK. Fragile X mental retardation protein (FMRP) and the spinal sensory system. Results Probl Cell Differ 2012; 54:41-59. [PMID: 22009347 DOI: 10.1007/978-3-642-21649-7_4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The purpose of this chapter is to discuss the role of the fragile X mental retardation protein (FMRP) in the spinal sensory system and the potential for use of the mouse model of fragile X syndrome to better understand some aspects of the human syndrome as well as advance knowledge in other areas of investigation, such as pain amplification, an important aspect of clinical pain disorders. We describe how the Fmr1 knockout mouse can be used to better understand the role of Fmrp in axons using cultures of sensory neurons and using manipulations to these neurons in vivo. We also discuss the established evidence for a role of Fmrp in nociceptive sensitization and how this evidence relates to an emerging role of translation control as a key process in pain amplification. Finally, we explore opportunities centered on the Fmr1 KO mouse for gaining further insight into the role of translation control in pain amplification and how this model may be used to identify novel therapeutic targets. We conclude that the study of the spinal sensory system in the Fmr1 KO mouse presents several unique prospects for gaining better insight into the human disorder and other clinical issues, such as chronic pain disorders, that affect millions of people worldwide.
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Affiliation(s)
- Theodore J Price
- Department of Pharmacology, The University of Arizona School of Medicine, Tucson, AZ, USA.
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Electroacupuncture inhibits phosphorylation of spinal phosphatidylinositol 3-kinase/Akt in a carrageenan-induced inflammatory rat model. Brain Res Bull 2011; 87:199-204. [PMID: 22155296 DOI: 10.1016/j.brainresbull.2011.11.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Revised: 09/30/2011] [Accepted: 11/15/2011] [Indexed: 12/12/2022]
Abstract
We investigated the changes of pain-related spinal signaling pathway after electroacupuncture (EA) stimulation in a carrageenan-induced rat model. EA stimulation (2Hz, 1mA) was needle-delivered for 30 min at acupoints corresponding to Zusanli and Sanyinjiao 3 h after carrageenan injection. Thermal and mechanical sensitivity of the hindpaw induced by carrageenan was strongly inhibited by EA stimulation. Phosphorylation of extracellular signal-regulated kinase, phosphatidylinositol 3-kinase (PI3K), Akt, and cAMP response element-binding protein (CREB) were examined in the L4-5 segments of the spinal cord by Western blot analysis 4h and 5h after carrageenan injection. Phosphorylation of Akt and especially PI3K were significantly induced by carrageenan-induction, but these expressions were markedly inhibited by EA stimulation. CREB phosphorylation showed a similar, but insignificant, pattern as like PI3k/Akt. Immunohistochemical analyses confirmed that phosphorylation of PI3K and Akt showed a similar pattern as Western blotting and were observed in most neurons and a few astrocytes. EA and PI3K inhibitor synergistically inhibited carrageenan-induced hyperalgesia. These results reveal that both neuronal PI3K and Akt may play an important role in EA-induced antinociception via inactivation in an inflammatory pain model.
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Anavi-Goffer S, Baillie G, Irving AJ, Gertsch J, Greig IR, Pertwee RG, Ross RA. Modulation of L-α-lysophosphatidylinositol/GPR55 mitogen-activated protein kinase (MAPK) signaling by cannabinoids. J Biol Chem 2011; 287:91-104. [PMID: 22027819 DOI: 10.1074/jbc.m111.296020] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
GPR55 is activated by l-α-lysophosphatidylinositol (LPI) but also by certain cannabinoids. In this study, we investigated the GPR55 pharmacology of various cannabinoids, including analogues of the CB1 receptor antagonist Rimonabant®, CB2 receptor agonists, and Cannabis sativa constituents. To test ERK1/2 phosphorylation, a primary downstream signaling pathway that conveys LPI-induced activation of GPR55, a high throughput system, was established using the AlphaScreen® SureFire® assay. Here, we show that CB1 receptor antagonists can act both as agonists alone and as inhibitors of LPI signaling under the same assay conditions. This study clarifies the controversy surrounding the GPR55-mediated actions of SR141716A; some reports indicate the compound to be an agonist and some report antagonism. In contrast, we report that the CB2 ligand GW405833 behaves as a partial agonist of GPR55 alone and enhances LPI signaling. GPR55 has been implicated in pain transmission, and thus our results suggest that this receptor may be responsible for some of the antinociceptive actions of certain CB2 receptor ligands. The phytocannabinoids Δ9-tetrahydrocannabivarin, cannabidivarin, and cannabigerovarin are also potent inhibitors of LPI. These Cannabis sativa constituents may represent novel therapeutics targeting GPR55.
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Affiliation(s)
- Sharon Anavi-Goffer
- School of Medical Sciences, Institute of Medical Sciences, Kosterlitz Centre for Therapeutics, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, United Kingdom; Departments of Behavioral Sciences and Molecular Biology, Ariel University Center of Samaria, Ariel 40700, Israel.
| | - Gemma Baillie
- School of Medical Sciences, Institute of Medical Sciences, Kosterlitz Centre for Therapeutics, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, United Kingdom
| | - Andrew J Irving
- Division of Medical Sciences, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, Scotland, United Kingdom
| | - Jürg Gertsch
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, Bern CH-3012, Switzerland
| | - Iain R Greig
- School of Medical Sciences, Institute of Medical Sciences, Kosterlitz Centre for Therapeutics, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, United Kingdom
| | - Roger G Pertwee
- School of Medical Sciences, Institute of Medical Sciences, Kosterlitz Centre for Therapeutics, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, United Kingdom
| | - Ruth A Ross
- School of Medical Sciences, Institute of Medical Sciences, Kosterlitz Centre for Therapeutics, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, United Kingdom
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da Silva KABS, Manjavachi MN, Paszcuk AF, Pivatto M, Viegas C, Bolzani VS, Calixto JB. Plant derived alkaloid (-)-cassine induces anti-inflammatory and anti-hyperalgesics effects in both acute and chronic inflammatory and neuropathic pain models. Neuropharmacology 2011; 62:967-77. [PMID: 22032869 DOI: 10.1016/j.neuropharm.2011.10.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Revised: 09/27/2011] [Accepted: 10/01/2011] [Indexed: 11/25/2022]
Abstract
Natural products have been revealed as relevant sources of therapeutic agents including those for the management of pain states. In this study, the anti-nociceptive and anti-inflammatory effects of (-)-cassine, isolated from Senna spectabilis were evaluated using pharmacological, behavioural and biochemical approaches. Oral treatment with (-)-cassine (3-30 mg/kg) reduced carrageenan-induced mechanical and thermal nociception associated with the suppression of myeloperoxidase activity in the mouse paw. Moreover, (-)-cassine (1-10 μg/site) prevented mechanical hyperalgesia induced by carrageenan when given through the intraplantar (i.pl.), spinal and intracerebroventricular routes. Additionally, oral treatment with (-)-cassine (3-60 mg/kg) prevented the mechanical hyperalgesia elicited by intraplantar injection of prostaglandin E(2), complete Freund's adjuvant, interleukin-1β, interleukin-6 and keratinocyte-derived chemokine. Furthermore, (-)-cassine inhibited the mechanical nociceptive response induced by ligation of the sciatic nerve and also significantly reduced the levels of cytokines/chemokines in paw tissue following i.pl. injection of carrageenan. In addition, the anti-nociceptive and anti-inflammatory actions of (-)-cassine were associated with its ability to interact with both TRPV1 and TRPA1 receptors and by inhibiting the upregulation of cyclooxigenase-2 as well as inhibiting the phosphorylation of MAPK/ERK and the transcription factor NF-κB. It is important to highlight that oral treatment with (-)-cassine did not produce any effects related to temperature, locomotor activity or catalepsy. Altogether, the present data demonstrate that (-)-cassine has systemic, spinal and supraspinal anti-nociceptive properties when assessed in inflammatory and neuropathic pain models. These effects are associated with its ability to block several signalling pathways associated with inflammatory and nociceptive responses. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'.
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Affiliation(s)
- Kathryn A B S da Silva
- Department of Pharmacology, Centre of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
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Han NR, Kim HM, Jeong HJ. Inactivation of cystein-aspartic acid protease (caspase)-1 by saikosaponin A. Biol Pharm Bull 2011; 34:817-23. [PMID: 21628878 DOI: 10.1248/bpb.34.817] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This work investigates the anti-inflammatory mechanism of saikosaponin A (SA), a major component of Bupleurum falcatum LINNE. SA significantly inhibited phorbol myristate acetate (PMA) plus A23187-induced the production and expression of interleukin (IL)-6 and tumor necrosis factor (TNF)-α in human mast cell (HMC)-1 cells. SA suppressed PMA plus A23187-induced phosphorylation of extracellular signal-regulated kinase and p38. When HMC-1 cells were treated with SA, translocation of nuclear factor (NF)-κB/Rel A into nucleus and degradation of inhibitor of NF-κB (IκB) in cytoplasm were inhibited. SA decreased PMA plus A23187-induced cysteine-aspartic acid protease (caspase)-1 activity. IL-1β production was also inhibited by SA. Finally, SA significantly decreased the number of nasal rubs and serum TNF-α level in the ovalbumin-sensitized allergic rhinitis mouse model. The underlying mechanism involves, at least in part, inactivation of caspase-1, which provides new evidence for therapeutic application of SA to target inflammatory processes.
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Affiliation(s)
- Na-Ra Han
- Department of Pharmacology, College of Oriental Medicine, Kyung Hee University, Seoul, Republic of Korea
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Yang K, Takeuchi K, Wei F, Dubner R, Ren K. Activation of group I mGlu receptors contributes to facilitation of NMDA receptor membrane current in spinal dorsal horn neurons after hind paw inflammation in rats. Eur J Pharmacol 2011; 670:509-18. [PMID: 21951968 DOI: 10.1016/j.ejphar.2011.09.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Revised: 08/10/2011] [Accepted: 09/10/2011] [Indexed: 10/17/2022]
Abstract
The interaction between the group I metabotropic glutamate (mGlu) receptors and N-methyl-D-aspartate (NMDA) receptors plays a critical role in spinal hyperexcitability and hyperalgesia. The cellular mechanisms underlying this interaction remain unknown. Utilizing an ex vivo spinal slice preparation from young adult rats, we investigated the group I mGlu receptor modulation of NMDA receptor-mediated current in superficial dorsal horn neurons by patch clamp recording after complete Freund's adjuvant (CFA)-induced hind paw inflammation. We show that NMDA receptor-mediated dorsal root stimulation-evoked EPSC (eEPSC) and NMDA-induced current was enhanced in the inflamed rats, compared to naïve rats and this effect was attenuated by AIDA (1 mM), a group I mGlu receptor antagonist. There were also increases in the frequency and amplitude of miniature excitatory postsynaptic currents in the presence of tetrodotoxin, suggesting enhanced presynaptic glutamate release probability and postsynaptic membrane responsiveness in inflamed rats. DHPG (10 μM), a selective group I mGlu receptor agonist, further facilitated NMDA receptor-mediated eEPSC and NMDA-induced current in inflamed rats. The DHPG-produced facilitation of NMDA-induced current was blocked by intracellular dialysis of GDP-beta-S (1 mM), a G protein antagonist, and BAPTA (15 mM), an intracellular calcium chelating agent; and by pretreatment with U73,122 (10 μM), a PLC inhibitor, or 2-APB (100 μM), an IP₃-receptor antagonist. These findings support the hypothesis that signal transduction coupling between group I mGlu receptors and NMDA receptors underlies the activation of NMDA receptors in spinal hyperexcitability and hyperalgesia.
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Affiliation(s)
- Kun Yang
- Department of Neural and Pain Sciences, School of Dentistry and Program in Neuroscience, University of Maryland, Baltimore, MD 21201, USA
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45
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Lai HH, Qiu CS, Crock LW, Morales MEP, Ness TJ, Gereau RW. Activation of spinal extracellular signal-regulated kinases (ERK) 1/2 is associated with the development of visceral hyperalgesia of the bladder. Pain 2011; 152:2117-2124. [PMID: 21705143 PMCID: PMC3157542 DOI: 10.1016/j.pain.2011.05.017] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Revised: 05/03/2011] [Accepted: 05/17/2011] [Indexed: 12/24/2022]
Abstract
Activation of extracellular signal-regulated kinases (ERK) 1/2 in dorsal horn neurons is important for the development of somatic hypersensitivity and spinal central sensitization after peripheral inflammation. However, data regarding the roles of spinal ERK1/2 in the development of visceral hyperalgesia are sparse. Here we studied the activation of ERK1/2 in the lumbosacral spinal cord after innocuous and noxious distention of the inflamed (cyclophosphamide-treated) and noninflamed urinary bladder in mice. We also correlated the spinal ERK1/2 activation to distention-evoked bladder nociception as quantified by the abdominal visceromotor response (VMR). Cyclophosphamide treatment (bladder inflammation) evoked increased bladder hyperalgesia and allodynia to bladder distention, as evident from an upward and leftward shift of the VMR stimulus-response curve compared with that of noninflamed mice. Development of bladder hyperalgesia was associated with robust enhancement of ERK1/2 activation in the dorsal horn and deeper laminae bilaterally in the L6-S1 spinal cord. Functional blockade of spinal ERK1/2 activity via intrathecal administration of the upstream MEK inhibitor U0126 attenuated distention-evoked bladder nociception and caused a significant downward shift of the VMR stimulus-response curve. In summary, we have provided functional and immunohistochemical evidence that activation of lumbosacral spinal ERK1/2 is associated with the development of primary visceral (bladder) hyperalgesia. Our results suggest that aberrant processing of visceral nociceptive information at the level of the lumbosacral spinal cord via activation of ERK1/2 signaling may contribute to chronic bladder pain in the context of inflammation.
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Affiliation(s)
- H. Henry Lai
- Department of Surgery, Division of Urologic Surgery, Washington University School of Medicine, St Louis, MO
- Department of Surgery, St Louis Veterans Affairs Medical Center, St Louis, MO
| | - Chang-Shen Qiu
- Department of Surgery, Division of Urologic Surgery, Washington University School of Medicine, St Louis, MO
- Department of Anesthesiology and Washington University Pain Center, Washington University School of Medicine, St Louis, MO
| | - Lara W. Crock
- Department of Anesthesiology and Washington University Pain Center, Washington University School of Medicine, St Louis, MO
| | - Maria Elena P. Morales
- Department of Anesthesiology and Washington University Pain Center, Washington University School of Medicine, St Louis, MO
| | - Tim J. Ness
- Department of Anesthesiology, University of Alabama at Birmingham, Birmingham, AL
| | - Robert W. Gereau
- Department of Anesthesiology and Washington University Pain Center, Washington University School of Medicine, St Louis, MO
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Spinal protein kinase M ζ underlies the maintenance mechanism of persistent nociceptive sensitization. J Neurosci 2011; 31:6646-53. [PMID: 21543593 DOI: 10.1523/jneurosci.6286-10.2011] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Sensitization of the pain pathway is believed to promote clinical pain disorders. We hypothesized that the persistence of a sensitized state in the spinal dorsal horn might depend on the activity of protein kinase M ζ (PKMζ), an essential mechanism of late long-term potentiation (LTP). To test this hypothesis, we used intraplantar injections of interleukin-6 (IL-6) in mice to elicit a transient allodynic state that endured ∼3 d. After the resolution of IL-6-induced allodynia, a subsequent intraplantar injection of prostaglandin E(2) (PGE(2)) or intrathecal injection of the metabotropic glutamate receptor 1/5 (mGluR1/5) agonist DHPG (dihydroxyphenylglycol) precipitated allodynia and/or nocifensive responses. Intraplantar injection of IL-6 followed immediately by intrathecal injection of a PKMζ inhibitor prevented the expression of subsequent PGE(2)-induced allodynia. Inhibitors of protein translation were effective in preventing PGE(2)-induced allodynia when given immediately after IL-6, but not after the initial allodynia had resolved. In contrast, spinal PKMζ inhibition completely abolished both prolonged allodynia to hindpaw PGE(2) and enhanced nocifensive behaviors evoked by intrathecal mGluR1/5 agonist injection after the resolution of IL-6-induced allodynia. Moreover, spinal PKMζ inhibition prevented the enhanced response to subsequent stimuli following resolution of hypersensitivity induced by plantar incision. The present findings demonstrate that the spinal cord encodes an engram for persistent nociceptive sensitization that is analogous to molecular mechanisms of late LTP and suggest that spinally directed PKMζ inhibitors may offer therapeutic benefit for injury-induced pain states.
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Inhibition of ERK phosphorylation by substance P N-terminal fragment decreases capsaicin-induced nociceptive response. Neuropharmacology 2011; 61:608-13. [PMID: 21601581 DOI: 10.1016/j.neuropharm.2011.04.035] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2010] [Revised: 04/09/2011] [Accepted: 04/20/2011] [Indexed: 11/21/2022]
Abstract
Previous research has demonstrated that substance P N-terminal fragments produced by the action of several different enzymes in the spinal cord could reduce nociception when injected intrathecally (i.t.) into mice. The present study examined the possible involvement of spinal extracellular signal-regulated protein kinase (ERK), a mitogen-activated protein kinase (MAPK), in i.t. substance P (1-7)-induced antinociception as assayed by the capsaicin test. The i.t. injection of substance P (1-7) (20-80 nmol) into mice resulted in a dose-dependent attenuation of paw-licking/biting behavior induced by intraplantar injection of capsaicin, which was reversed by co-injection of [D-Pro(2), D-Phe(7)]substance P (1-7), a D-isomer and antagonist of substance P (1-7). In Western blot analysis, intraplantar injection of capsaicin (400 and 1600 ng/paw) produced an increase of ERK phosphorylation in the dorsal spinal cord, whereas expression of p38 and c-Jun N-terminal kinase (JNK) phosphorylation was unchanged by capsaicin treatment. In parallel to the behavioral results, i.t. substance P (1-7) inhibited capsaicin-induced ERK phosphorylation, which was reversed by [D-Pro(2), D-Phe(7)]substance P (1-7), a substance P (1-7) antagonist. Both nociceptive behavioral response and spinal ERK activation induced by intraplantar capsaicin were reduced by U0126, an upstream inhibitor of ERK phosphorylation. Taken together, these findings suggest that the activation of ERK, but not p38 and JNK MAPKs in the spinal cord, contributes to intraplantar capsaicin-induced nociception, and that blocking ERK activation via substance P (1-7) binding sites may provide significant antinociception at the spinal cord level.
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Klinger M, Sacks S, Cervero F. A role for extracellular signal-regulated kinases 1 and 2 in the maintenance of persistent mechanical hyperalgesia in ovariectomized mice. Neuroscience 2011; 172:483-93. [DOI: 10.1016/j.neuroscience.2010.10.043] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Revised: 10/14/2010] [Accepted: 10/15/2010] [Indexed: 12/13/2022]
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Hypersensitivity to mGluR5 and ERK1/2 leads to excessive protein synthesis in the hippocampus of a mouse model of fragile X syndrome. J Neurosci 2010; 30:15616-27. [PMID: 21084617 DOI: 10.1523/jneurosci.3888-10.2010] [Citation(s) in RCA: 295] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Fragile X syndrome (FXS) is caused by loss of the FMR1 gene product FMRP (fragile X mental retardation protein), a repressor of mRNA translation. According to the metabotropic glutamate receptor (mGluR) theory of FXS, excessive protein synthesis downstream of mGluR5 activation causes the synaptic pathophysiology that underlies multiple aspects of FXS. Here, we use an in vitro assay of protein synthesis in the hippocampus of male Fmr1 knock-out (KO) mice to explore the molecular mechanisms involved in this core biochemical phenotype under conditions where aberrant synaptic physiology has been observed. We find that elevated basal protein synthesis in Fmr1 KO mice is selectively reduced to wild-type levels by acute inhibition of mGluR5 or ERK1/2, but not by inhibition of mTOR (mammalian target of rapamycin). The mGluR5-ERK1/2 pathway is not constitutively overactive in the Fmr1 KO, however, suggesting that mRNA translation is hypersensitive to basal ERK1/2 activation in the absence of FMRP. We find that hypersensitivity to ERK1/2 pathway activation also contributes to audiogenic seizure susceptibility in the Fmr1 KO. These results suggest that the ERK1/2 pathway, and other neurotransmitter systems that stimulate protein synthesis via ERK1/2, represent additional therapeutic targets for FXS.
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Abstract
The extracellular signal-regulated kinase (ERK) isoforms, ERK1 and ERK2, are believed to be key signaling molecules in nociception and nociceptive sensitization. Studies using inhibitors targeting the shared ERK1/2 upstream activator, mitogen-activated protein kinase kinase (MEK), and transgenic mice expressing a dominant-negative form of MEK have established the importance of ERK1/2 signaling. However, these techniques do not discriminate between ERK1 and ERK2. To dissect the function of each isoform in pain, we used mice with a targeted genetic deletion of ERK1 [ERK1 knock-out (KO)] to test the hypothesis that ERK1 is required for behavioral sensitization in rodent pain models. Despite activation (phosphorylation) of ERK1 after acute noxious stimulation and in models of chronic pain, we found that ERK1 was not required for formalin-induced spontaneous behaviors, complete Freund's adjuvant-induced heat and mechanical hypersensitivity, and spared nerve injury-induced mechanical hypersensitivity. However, ERK1 deletion did delay formalin-induced long-term heat hypersensitivity, without affecting formalin-induced mechanical hypersensitivity, suggesting that ERK1 partially shapes long-term responses to formalin. Interestingly, ERK1 deletion resulted in elevated basal ERK2 phosphorylation. However, this did not appear to influence nociceptive processing, since inflammation-induced ERK2 phosphorylation and pERK1/2 immunoreactivity in spinal cord were not elevated in ERK1 KO mice. Additionally, systemic MEK inhibition with SL327 (alpha-[amino[(4-aminophenyl)thio]methylene]-2-(trifluoromethyl)benzeneacetonitrile) attenuated formalin-induced spontaneous behaviors similarly in wild-type and ERK1 KO mice, indicating that unrelated signaling pathways do not functionally compensate for the loss of ERK1. Together, these results suggest that ERK1 plays a limited role in nociceptive sensitization and support a predominant role for ERK2 in these processes.
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