1
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Lyu C, Xiao H, Yin X, Li Z, Han C, Xu R. Acupuncture in Multiple Myeloma Peripheral Neuropathy: A Systematic Review. J Pain Res 2024; 17:1571-1581. [PMID: 38699068 PMCID: PMC11063468 DOI: 10.2147/jpr.s448634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 04/04/2024] [Indexed: 05/05/2024] Open
Abstract
Background Peripheral neuropathy (PN) is a prevalent complication of multiple myeloma (MM), due to the disease itself or its treatment. Despite extensive research, the optimal treatment for multiple myeloma peripheral neuropathy (MMPN) remains unclear. Clinical practice has shown the potential efficacy of acupuncture in managing MMPN. This study aimed to conduct a comprehensive analysis of the literature to assess the effectiveness and safety of acupuncture as a treatment for MMPN. Methods The PubMed, Web of Science, MEDLINE, Cochrane Library, and Embase databases were comprehensively searched from inception to November 1, 2023 to identify relevant studies pertaining to the use of acupuncture to treat MMPN. Results A total of five studies, encompassing 97 patients diagnosed with drug-related PN, were ultimately included in this analysis. The literature lacks any reports pertaining to the utilization of acupuncture for disease-related PN. ST36, LI4, SP6, and EX-LE-10 were found to be the most frequently chosen acupoints. Following acupuncture treatment, there was a consistent reduction in scores on the Visual Analogue Scale (VAS), Neuropathic Pain Scale (NPS), Brief Pain Inventory-Short Form (BPI-SF), and Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity (FACT/GOG-Ntx) among MMPN patients. The results of Nerve Conduction Velocity (NCV) tests yielded conflicting results. No severe adverse effects were reported. Conclusion The use of acupuncture for disease-related PN has not been studied to date. Acupuncture is safe for drug-related PN and is helpful for relieving pain. But uncertainty exists regarding the efficacy of this approach because there is substantial heterogeneity with respect to acupuncture treatment regimens, and more high-quality studies on this topic are warranted.
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Affiliation(s)
- Chunyi Lyu
- First Clinical Medical College, Shandong University of Traditional Chinese Medicine, Jinan, 250014, People’s Republic of China
| | - Hongyan Xiao
- First Clinical Medical College, Shandong University of Traditional Chinese Medicine, Jinan, 250014, People’s Republic of China
| | - Xuewei Yin
- Affiliated Eye Hospital of Shandong University of Traditional Chinese Medicine, Jinan, 250002, People’s Republic of China
| | - Zonghong Li
- First Clinical Medical College, Shandong University of Traditional Chinese Medicine, Jinan, 250014, People’s Republic of China
| | - Chen Han
- First Clinical Medical College, Shandong University of Traditional Chinese Medicine, Jinan, 250014, People’s Republic of China
| | - Ruirong Xu
- Key Laboratory of Integrated Traditional Chinese and Western Medicine for Hematology, Health Commission of Shandong Province; Institute of Hematology, Shandong University of Traditional Chinese Medicine, Jinan, 250014, People’s Republic of China
- Department of Hematology, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, 250014, People’s Republic of China
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2
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Zhou X, Zhang YC, Lu KQ, Xiao R, Tang WC, Wang F. The Role of p38 Mitogen-Activated Protein Kinase-Mediated F-Actin in the Acupuncture-Induced Mitigation of Inflammatory Pain in Arthritic Rats. Brain Sci 2024; 14:380. [PMID: 38672029 PMCID: PMC11048453 DOI: 10.3390/brainsci14040380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 04/09/2024] [Accepted: 04/11/2024] [Indexed: 04/28/2024] Open
Abstract
The analgesic efficacy of acupuncture has been widely recognized. However, the mechanism by which manual acupuncture-generated mechanical stimuli translate into biological signals remains unclear. This study employed a CFA-induced inflammatory pain rat model. Acupuncture intervention was then performed following standardized procedures. Enzyme-linked immunosorbent assay (ELISA) assessed inflammatory cytokines levels, while immunofluorescence and qRT-PCR screened the level of p38 and F-actin expression in the ST36 acupoint area of rats. Results indicated increased inflammatory factors, including IL-1β and TNFα, with reduced paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency (PWTL) in CFA rats compared to unmodeled rats. After acupuncture intervention, the heightened expression level of F-actin and p38 mRNA and the phosphorylation of p38 in the acupoint area was observed alongside decreased inflammatory factors in diseased ankle joints. The application of lifting and thrusting manipulations further enhanced the effect of acupuncture, in which the molecular expression level of muscle and connective tissue increased most significantly, indicating that these two tissues play a major role in the transformation of acupuncture stimulation. Moreover, antagonizing p38 expression hindered acupuncture efficacy, supporting the hypothesis that p38 MAPK-mediated F-actin transduces mechanical signals generated by acupuncture and related manipulation into biological signals.
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Affiliation(s)
| | | | | | | | | | - Fan Wang
- School of Acupuncture-Moxibustion and Tuina, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China; (X.Z.); (Y.-C.Z.); (K.-Q.L.); (R.X.); (W.-C.T.)
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3
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Messina DN, Peralta ED, Acosta CG. Complex alterations in inflammatory pain and analgesic sensitivity in young and ageing female rats: involvement of ASIC3 and Nav1.8 in primary sensory neurons. Inflamm Res 2024; 73:669-691. [PMID: 38483556 DOI: 10.1007/s00011-024-01862-z] [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: 10/11/2023] [Revised: 02/05/2024] [Accepted: 02/12/2024] [Indexed: 04/10/2024] Open
Abstract
OBJECTIVE AND DESIGN Our aim was to determine an age-dependent role of Nav1.8 and ASIC3 in dorsal root ganglion (DRG) neurons in a rat pre-clinical model of long-term inflammatory pain. METHODS We compared 6 and 24 months-old female Wistar rats after cutaneous inflammation. We used behavioral pain assessments over time, qPCR, quantitative immunohistochemistry, selective pharmacological manipulation, ELISA and in vitro treatment with cytokines. RESULTS Older rats exhibited delayed recovery from mechanical allodynia and earlier onset of spontaneous pain than younger rats after inflammation. Moreover, the expression patterns of Nav1.8 and ASIC3 were time and age-dependent and ASIC3 levels remained elevated only in aged rats. In vivo, selective blockade of Nav1.8 with A803467 or of ASIC3 with APETx2 alleviated mechanical and cold allodynia and also spontaneous pain in both age groups with slightly different potency. Furthermore, in vitro IL-1β up-regulated Nav1.8 expression in DRG neurons cultured from young but not old rats. We also found that while TNF-α up-regulated ASIC3 expression in both age groups, IL-6 and IL-1β had this effect only on young and aged neurons, respectively. CONCLUSION Inflammation-associated mechanical allodynia and spontaneous pain in the elderly can be more effectively treated by inhibiting ASIC3 than Nav1.8.
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Affiliation(s)
- Diego N Messina
- Laboratory of Neurobiology of Pain, Faculty of Medical Sciences, IHEM (Instituto de Histologia y Embriologia Mendoza, Dr. Mario H Burgos), Cuyo National University, Av. Del Libertador 80, 5500, Mendoza, Argentina
| | - Emanuel D Peralta
- Laboratory of Neurobiology of Pain, Faculty of Medical Sciences, IHEM (Instituto de Histologia y Embriologia Mendoza, Dr. Mario H Burgos), Cuyo National University, Av. Del Libertador 80, 5500, Mendoza, Argentina
| | - Cristian G Acosta
- Laboratory of Neurobiology of Pain, Faculty of Medical Sciences, IHEM (Instituto de Histologia y Embriologia Mendoza, Dr. Mario H Burgos), Cuyo National University, Av. Del Libertador 80, 5500, Mendoza, Argentina.
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4
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Tanaka F, Mazzardo G, Salm DC, de Oliveira BH, Joaquim L, Machado RS, Cidreira T, Petronilho FC, Bittencourt EB, Bianco G, Bobinski F, Piovezan AP, Srbely JZ, Shah JP, Moré AOO, Mazzardo-Martins L, Martins DF. Peripheral Activation of Formyl Peptide Receptor 2/ALX by Electroacupuncture Alleviates Inflammatory Pain by Increasing Interleukin-10 Levels and Catalase Activity in Mice. Neuroscience 2023; 529:1-15. [PMID: 37572879 DOI: 10.1016/j.neuroscience.2023.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 07/31/2023] [Accepted: 08/03/2023] [Indexed: 08/14/2023]
Abstract
In the context of the electroacupuncture (EA) neurobiological mechanisms, we have previously demonstrated the involvement of formyl peptide receptor 2 (FPR2/ALX) in the antihyperalgesic effect of EA. The present study investigated the involvement of peripheral FPR2/ALX in the antihyperalgesic effect of EA on inflammatory cytokines levels, oxidative stress markers and antioxidant enzymes in an animal model of persistent inflammatory pain. Male Swiss mice underwent intraplantar (i.pl.) injection with complete Freund's adjuvant (CFA). Mechanical hyperalgesia was assessed with von Frey monofilaments. Animals were treated with EA (2/10 Hz, ST36-SP6, 20 minutes) for 4 consecutive days. From the first to the fourth day after CFA injection, animals received i.pl. WRW4 (FPR2/ALX antagonist) or saline before EA. Levels of inflammatory cytokines (TNF, IL-6, IL-4 and IL-10), antioxidant enzymes (catalase and superoxide dismutase), oxidative stress markers (TBARS, protein carbonyl, nitrite/nitrate ratio), and myeloperoxidase activity were measured in paw tissue samples. As previously demonstrated, i.pl. injection of the FPR2/ALX antagonist prevented the antihyperalgesic effect induced by EA. Furthermore, animals treated with EA showed higher levels of IL-10 and catalase activity in the inflamed paw, and these effects were prevented by the antagonist WRW4. EA did not change levels of TNF and IL-6, SOD and MPO activity, and oxidative stress markers. Our work demonstrates that the antihyperalgesic effect of EA on CFA-induced inflammatory pain could be partially associated with higher IL-10 levels and catalase activity, and that these effects may be dependent, at least in part, on the activation of peripheral FPR2/ALX.
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Affiliation(s)
- Fernanda Tanaka
- Postgraduate Program in Neuroscience, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil; Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - Gustavo Mazzardo
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil; Faculty of Medicine, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - Daiana C Salm
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil; Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - Bruna H de Oliveira
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil; Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - Larissa Joaquim
- Laboratory of Neurobiology of Inflammatory and Metabolic Processes (NEUROIMet), Postgraduate Program in Health Science, University of Southern Santa Catarina, Tubarão, Santa Catarina, Brazil
| | - Richard S Machado
- Laboratory of Neurobiology of Inflammatory and Metabolic Processes (NEUROIMet), Postgraduate Program in Health Science, University of Southern Santa Catarina, Tubarão, Santa Catarina, Brazil
| | - Thaina Cidreira
- Laboratory of Neurobiology of Inflammatory and Metabolic Processes (NEUROIMet), Postgraduate Program in Health Science, University of Southern Santa Catarina, Tubarão, Santa Catarina, Brazil
| | - Fabrícia C Petronilho
- Laboratory of Neurobiology of Inflammatory and Metabolic Processes (NEUROIMet), Postgraduate Program in Health Science, University of Southern Santa Catarina, Tubarão, Santa Catarina, Brazil
| | | | - Gianluca Bianco
- Research Laboratory of Posturology and Neuromodulation RELPON, Department of Human Neuroscience, Sapienza University, Italy; Istituto di Formazione in Agopuntura e Neuromodulazione IFAN, Roma, Italy
| | - Franciane Bobinski
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil; Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - Anna Paula Piovezan
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil; Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - John Z Srbely
- Department of Human Health and Nutritional Science, University of Guelph, Guelph, Ontario, Canada
| | - Jay P Shah
- Rehabilitation Medicine Department, National Institutes of Health, Rockville Pike, Bethesda, MD, USA
| | - Ari O O Moré
- Integrative Medicine and Acupuncture Service, University Hospital, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Leidiane Mazzardo-Martins
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil; Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - Daniel F Martins
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil; Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil.
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5
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Zhou J, Zeng F, Cheng S, Dong X, Jiang N, Zhang X, Tang C, He W, Chen Y, Sun N, Zhou Y, Li X, Hu S, Sun R, Wintermark M, Yang W, Liang F, Li Z. Modulation effects of different treatments on periaqueductal gray resting state functional connectivity in knee osteoarthritis knee pain patients. CNS Neurosci Ther 2023. [PMID: 36890655 DOI: 10.1111/cns.14153] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 02/06/2023] [Accepted: 02/21/2023] [Indexed: 03/10/2023] Open
Abstract
BACKGROUND The analgesic effect of acupuncture is widely recognized, but the mechanical characteristics of acupuncture for pain relief, compared to non-steroidal anti-inflammatory (NSAIDs) and placebo medication, remain unknown. AIMS To compare the modulation effects of acupuncture treatment with NSAIDs and placebo medication on descending pain modulation system (DPMS) in knee osteoarthritis (KOA) patients. METHODS This study recruited 180 KOA patients with knee pain and 41 healthy controls (HCs). Individuals with KOA knee pain were divided randomly into groups of verum acupuncture (VA), sham acupuncture (SA), celecoxib (SC), placebo (PB), and waiting list (WT), with 36 patients in each group. VA and SA groups included ten sessions of puncturing acupoints or puncturing non-acupoints acupuncture treatment for two successive weeks. Celecoxib capsules were continuously given orally to patients in the SC group at a dosage of 200 mg daily for 2 weeks. In the PB group, patients received a placebo capsule once a day for 2 weeks at the same dosage as celecoxib capsules. In the WL group, patients did not receive any treatment. Patients underwent a resting-state BOLD-fMRI scan pre- and post-receiving the therapy, whereas HCs only underwent a baseline scan. Seed (ventrolateral periaqueductal gray, vlPAG, a key node in DPMS) based resting-state functional connectivity (rs-FC) was applied in the data analysis. RESULTS All groups demonstrated improved knee pain scores relative to the initial state. There was no statistical difference between the VA and SA groups in all clinical outcomes, and vlPAG rs-FC alterations. KOA knee pain individuals reported higher vlPAG rs-FC in the bilateral thalamus than HCs. KOA knee pain patients in the acupuncture group (verum + sham, AG) exhibited increased vlPAG rs-FC with the right dorsolateral prefrontal cortex (DLPFC) and the right angular, which is associated with knee pain improvement. In contrast with the SC and PB group, the AG exhibited significantly increased vlPAG rs-FC with the right DLPFC and angular. Contrary to the WT group, the AG showed greater vlPAG rs-FC with the right DLPFC and precuneus. CONCLUSIONS Acupuncture treatment, celecoxib, and placebo medication have different modulation effects on vlPAG DPMS in KOA knee pain patients. Acupuncture could modulate vlPAG rs-FC with brain regions associated with cognitive control, attention, and reappraisal for knee pain relief in KOA patients, compared with celecoxib and placebo medication.
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Affiliation(s)
- Jun Zhou
- Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Fang Zeng
- Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Acupuncture & Brain Research Center, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Shirui Cheng
- Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Acupuncture & Brain Research Center, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Xiaohui Dong
- Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Acupuncture & Brain Research Center, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Nannan Jiang
- Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Xinyue Zhang
- Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Acupuncture & Brain Research Center, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Chenjian Tang
- Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Wenhua He
- The Second Affiliated Hospital of Shanxi, University of Traditional Chinese Medicine, Taiyuan, China
| | - Yang Chen
- Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Ning Sun
- Rehabilitation Medicine Center and Institute of Rehabilitation Medicine, West China Hospital, Sichuan University, Chengdu, China.,Key Laboratory of Rehabilitation Medicine in Sichuan Province, Chengdu, China
| | - Yuanfang Zhou
- Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Xinling Li
- Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Shengjie Hu
- Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Ruirui Sun
- Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Acupuncture & Brain Research Center, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Max Wintermark
- Radiology Department, Stanford University, Stanford, California, USA
| | - Weihua Yang
- Dali Bai Autonomous Prefecture Chinese Medicine Hospital, Dali, China
| | - Fanrong Liang
- Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Zhengjie Li
- Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Acupuncture & Brain Research Center, Chengdu University of Traditional Chinese Medicine, Chengdu, China
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6
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YUAN W, YUE JX, WANG Q, WU N, LI YF, YANG XH, QIAO HF. Role of peptidergic neurons in modulating acupoint sensitization caused by neck acute inflammatory pain in rats 肽能神经元对颈部急性炎性痛模型大鼠穴位敏化的调节作用. WORLD JOURNAL OF ACUPUNCTURE-MOXIBUSTION 2022. [DOI: 10.1016/j.wjam.2022.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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7
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Oh JE, Kim SN. Anti-Inflammatory Effects of Acupuncture at ST36 Point: A Literature Review in Animal Studies. Front Immunol 2022; 12:813748. [PMID: 35095910 PMCID: PMC8790576 DOI: 10.3389/fimmu.2021.813748] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 12/15/2021] [Indexed: 12/12/2022] Open
Abstract
So far, a number of acupuncture studies have shown anti-inflammatory effects of acupuncture treatment, mostly known at specific point ST36. However, there is no literature that oversaw the inflammation-regulatory effects of acupuncture in each tissue. Therefore, we investigated how acupuncture at specific acupoint ST36 regulates inflammation and its underlying mechanisms. We searched literatures on PubMed until July 2021 using the keywords “animal, acupuncture, ST36, inflammation, immune,” and 292 literatures were searched. We ultimately selected 69 studies to determine the anti-inflammatory actions of acupuncture at ST36 and classified the changes of inflammatory mediators according to target regions. Forty-three studies were included in body fluids, 27 studies in the digestive system, 17 studies in the nervous system, and 30 studies in other tissues or organs. In this review, we found that acupuncture at ST36 has clinical benefits in relieving inflammation through several mechanisms such as vagus nerve activation, toll-like receptor 4 (TLR4)/NF-κB signaling, macrophage polarization, mitogen-activated protein kinase (MAPK) signaling pathway, and cholinergic anti-inflammatory pathway. We expect that these data will inform further studies related to ST36 acupuncture on inflammation.
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Affiliation(s)
- Ji-Eun Oh
- College of Korean Medicine, Dongguk University, Goyang, South Korea
| | - Seung-Nam Kim
- College of Korean Medicine, Dongguk University, Goyang, South Korea
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8
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Dou B, Li Y, Ma J, Xu Z, Fan W, Tian L, Chen Z, Li N, Gong Y, Lyu Z, Fang Y, Liu Y, Xu Y, Wang S, Chen B, Guo Y, Guo Y, Lin X. Role of Neuroimmune Crosstalk in Mediating the Anti-inflammatory and Analgesic Effects of Acupuncture on Inflammatory Pain. Front Neurosci 2021; 15:695670. [PMID: 34408622 PMCID: PMC8366064 DOI: 10.3389/fnins.2021.695670] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 07/05/2021] [Indexed: 12/17/2022] Open
Abstract
Inflammatory pain is caused by peripheral tissue injury and inflammation. Inflammation leads to peripheral sensitization, which may further cause central sensitization, resulting in chronic pain and progressive functional disability. Neuroimmune crosstalk plays an essential role in the development and maintenance of inflammatory pain. Studies in recent years have shown that acupuncture can exert anti-inflammatory and analgesic effects by regulating peripheral (i.e., involving local acupoints and inflamed regions) and central neuroimmune interactions. At the local acupoints, acupuncture can activate the TRPV1 and TRPV2 channels of mast cells, thereby promoting degranulation and the release of histamine, adenosine, and other immune mediators, which interact with receptors on nerve endings and initiate neuroimmune regulation. At sites of inflammation, acupuncture enables the recruitment of immune cells, causing the release of opioid peptides, while also exerting direct analgesic effects via nerve endings. Furthermore, acupuncture promotes the balance of immune cells and regulates the release of inflammatory factors, thereby reducing the stimulation of nociceptive receptors in peripheral organs. Acupuncture also alleviates peripheral neurogenic inflammation by inhibiting the release of substance P (SP) and calcitonin gene-related peptide from the dorsal root ganglia. At the central nervous system level, acupuncture inhibits the crosstalk between glial cells and neurons by inhibiting the p38 MAPK, ERK, and JNK signaling pathways and regulating the release of inflammatory mediators. It also reduces the excitability of the pain pathway by reducing the release of excitatory neurotransmitters and promoting the release of inhibitory neurotransmitters from neurons and glial cells. In conclusion, the regulation of neuroimmune crosstalk at the peripheral and central levels mediates the anti-inflammatory and analgesic effects of acupuncture on inflammatory pain in an integrated manner. These findings provide novel insights enabling the clinical application of acupuncture in the treatment of inflammatory diseases.
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Affiliation(s)
- Baomin Dou
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yanan Li
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Jie Ma
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Zhifang Xu
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China.,National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China.,School of Acupuncture & Moxibustion and Tuina, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Wen Fan
- Department of Rehabilitation Physical Therapy Course, Faculty of Health Science, Suzuka University of Medical Science, Suzuka, Japan
| | - Lixin Tian
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Zhihan Chen
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Ningcen Li
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yinan Gong
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Zhongxi Lyu
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China.,National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China.,School of Acupuncture & Moxibustion and Tuina, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yuxin Fang
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China.,National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China.,School of Acupuncture & Moxibustion and Tuina, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yangyang Liu
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China.,National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China.,School of Acupuncture & Moxibustion and Tuina, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yuan Xu
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China.,National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China.,School of Acupuncture & Moxibustion and Tuina, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Shenjun Wang
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China.,National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China.,School of Acupuncture & Moxibustion and Tuina, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Bo Chen
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China.,National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China.,School of Acupuncture & Moxibustion and Tuina, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yongming Guo
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China.,National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China.,School of Acupuncture & Moxibustion and Tuina, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yi Guo
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China.,National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China.,School of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Xiaowei Lin
- Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin, China.,National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China.,School of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, China
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9
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Li J, Zhang Y, Illes P, Tang Y, Rubini P. Increasing Efficiency of Repetitive Electroacupuncture on Purine- and Acid-Induced Pain During a Three-Week Treatment Schedule. Front Pharmacol 2021; 12:680198. [PMID: 34040538 PMCID: PMC8141797 DOI: 10.3389/fphar.2021.680198] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 04/15/2021] [Indexed: 12/11/2022] Open
Abstract
Acupuncture (AP) is an important constituent of the therapeutic repertoire of traditional Chinese medicine and has been widely used to alleviate chronic painful conditions all over the world. We studied in rats the efficiency of electroacupuncture (EAP) applied to the Zusanli acupoint (ST36) as an analgesic treatment over a 3-week period of time on purine (α,β-methylene ATP, dibenzoyl-ATP)- and acid (pH 6.0 medium)-induced pain in the rat paw. The two ATP derivatives stimulated P2X3 and P2X7 receptors, respectively, while the slightly acidic medium stimulated the “acid-sensitive ion channel 3” (ASIC3). It was found that the P2X7 receptor and ASIC-mediated pain was counteracted by EAP with greater efficiency at the end than at the beginning of the treatment schedule, while the P2X3 receptor–mediated pain was not. Our findings have important clinical and theoretical consequences, among others, because they are difficult to reconcile with the assumption that AP is primarily due to the release of peripheral and central opioid peptides causing the well-known tolerance to their effects. In consequence, AP is a convenient therapeutic instrument to treat subacute and chronic pain.
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Affiliation(s)
- Jie Li
- School of Acupuncture and Tuina, Chengdu University of Traditional Medicine, Chengdu, China
| | - Ying Zhang
- School of Acupuncture and Tuina, Chengdu University of Traditional Medicine, Chengdu, China
| | - Peter Illes
- School of Acupuncture and Tuina, Chengdu University of Traditional Medicine, Chengdu, China.,International Collaborative Center on Big Science Plan for Purinergic Signalling, Chengdu University of Traditional Medicine, Chengdu, China.,Rudolf Boehm Institute for Pharmacology and Toxicology, University of Leipzig, Leipzig, Germany
| | - Yong Tang
- School of Acupuncture and Tuina, Chengdu University of Traditional Medicine, Chengdu, China.,International Collaborative Center on Big Science Plan for Purinergic Signalling, Chengdu University of Traditional Medicine, Chengdu, China
| | - Patrizia Rubini
- School of Acupuncture and Tuina, Chengdu University of Traditional Medicine, Chengdu, China.,International Collaborative Center on Big Science Plan for Purinergic Signalling, Chengdu University of Traditional Medicine, Chengdu, China
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10
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Vieira C, Salm DC, Horewicz VV, Ludtke DD, Emer AA, Koerich JF, Mazzardo G, Elias S, Moré AOO, Mazzardo-Martins L, Cidral-Filho FJ, Reed WR, Piovezan AP, Martins DF. Electroacupuncture decreases inflammatory pain through a pro-resolving mechanism involving the peripheral annexin A1-formyl peptide receptor 2/ALX-opioid receptor pathway. Pflugers Arch 2021; 473:683-695. [PMID: 33474635 DOI: 10.1007/s00424-020-02502-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 10/28/2020] [Accepted: 12/03/2020] [Indexed: 12/31/2022]
Abstract
The pro-resolving mechanism is a recently described endogenous process that controls inflammation. The present study evaluated components of this mechanism, including annexin 1 (ANXA1) and the formyl peptide receptor 2/ALX (FPR2/ALX) receptor, in the antihyperalgesic effect induced by electroacupuncture (EA) in an animal model of persistent peripheral inflammation. Male Swiss mice underwent intraplantar (i.pl.) injection with complete Freund's adjuvant (CFA). Mechanical hyperalgesia was assessed with von Frey monofilaments. Animals were treated with EA (2-10 Hz, ST36-SP6) or subcutaneous BML-111 injection (FPR2/ALX agonist) for 5 consecutive days. In a separate set of experiments, on the first and fifth days after CFA injection, animals received i.pl. WRW4 (FPR2/ALX antagonist) or naloxone (non-selective opioid receptor antagonist) before EA or BML-111 injection. Paw protein levels of FPR2/ALX and ANXA1 were evaluated on the second day after CFA injection by western blotting technique. EA and BML-111 reduced mechanical hyperalgesia. I.pl. naloxone or WRW4 prevented the antihyperalgesic effect induced by either EA or BML-111. EA increased ANXA1 but did not alter FPR2/ALX receptor levels in the paw. Furthermore, i.pl. pretreatment with WRW4 prevented the increase of ANXA1 levels induced by EA. This work demonstrates that the EA antihyperalgesic effect on inflammatory pain involves the ANXA1/FPR2/ALX pro-resolution pathway. This effect appears to be triggered by the activation of FPR2/ALX receptors and crosstalk communication with the opioid system.
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Affiliation(s)
- Cintia Vieira
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil.,Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - Daiana C Salm
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil.,Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - Verônica V Horewicz
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil.,Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - Daniela D Ludtke
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil.,Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - Aline A Emer
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil.,Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - Júlia F Koerich
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil.,Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - Gustavo Mazzardo
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - Sayron Elias
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - Ari O O Moré
- Integrative Medicine and Acupuncture Division, University Hospital, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Leidiane Mazzardo-Martins
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil.,Postgraduate Program in Neuroscience, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Francisco J Cidral-Filho
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil.,Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - William R Reed
- Department of Physical Therapy, University of Alabama at Birmingham, Birmingham, AL, USA.,Rehabilitation Science Program, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Anna Paula Piovezan
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil.,Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil
| | - Daniel F Martins
- Experimental Neuroscience Laboratory (LaNEx), University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil. .,Postgraduate Program in Health Sciences, University of Southern Santa Catarina, Palhoça, Santa Catarina, Brazil.
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11
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Wei TH, Hsieh CL. Effect of Acupuncture on the p38 Signaling Pathway in Several Nervous System Diseases: A Systematic Review. Int J Mol Sci 2020; 21:E4693. [PMID: 32630156 PMCID: PMC7370084 DOI: 10.3390/ijms21134693] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 06/26/2020] [Accepted: 06/28/2020] [Indexed: 12/16/2022] Open
Abstract
Acupuncture is clinically used to treat various diseases and exerts positive local and systemic effects in several nervous system diseases. Advanced molecular and clinical studies have continually attempted to decipher the mechanisms underlying these effects of acupuncture. While a growing understanding of the pathophysiology underlying several nervous system diseases shows it to be related to inflammation and impair cell regeneration after ischemic events, the relationship between the therapeutic mechanism of acupuncture and the p38 MAPK signal pathway has yet to be elucidated. This review discusses the latest advancements in the identification of the effect of acupuncture on the p38 signaling pathway in several nervous system diseases. We electronically searched databases including PubMed, Embase, and the Cochrane Library from their inception to April 2020, using the following keywords alone or in various combinations: "acupuncture", "p38 MAPK pathway", "signaling", "stress response", "inflammation", "immune", "pain", "analgesic", "cerebral ischemic injury", "epilepsy", "Alzheimer's disease", "Parkinson's disease", "dementia", "degenerative", and "homeostasis". Manual acupuncture and electroacupuncture confer positive therapeutic effects by regulating proinflammatory cytokines, ion channels, scaffold proteins, and transcription factors including TRPV1/4, Nav, BDNF, and NADMR1; consequently, p38 regulates various phenomena including cell communication, remodeling, regeneration, and gene expression. In this review article, we found the most common acupoints for the relief of nervous system disorders including GV20, GV14, ST36, ST37, and LI4. Acupuncture exhibits dual regulatory functions of activating or inhibiting different p38 MAPK pathways, contributing to an overall improvement of clinical symptoms and function in several nervous system diseases.
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Affiliation(s)
- Tzu-Hsuan Wei
- Department of Chinese Medicine, China Medical University Hospital, Taichung 40447, Taiwan;
| | - Ching-Liang Hsieh
- Department of Chinese Medicine, China Medical University Hospital, Taichung 40447, Taiwan;
- Chinese Medicine Research Center, China Medical University, Taichung 40402, Taiwan
- Graduate Institute of Acupuncture Science, College of Chinese Medicine, China Medical University, Taichung 40402, Taiwan
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12
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Yen LT, Hsieh CL, Hsu HC, Lin YW. Preventing the induction of acid saline-induced fibromyalgia pain in mice by electroacupuncture or APETx2 injection. Acupunct Med 2020; 38:188-193. [PMID: 31986902 PMCID: PMC7278366 DOI: 10.1136/acupmed-2017-011457] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Fibromyalgia (FM) is a syndrome involving chronic pain, fatigue, sleep difficulties, morning stiffness and muscle cramping lasting longer than 3 months. The epidemiological prevalence is approximately 3-5% in women and increases with age. Antagonism of acid-sensing ion channel 3 (ASIC3) reportedly attenuates acid saline-induced FM pain in mice. AIMS Whether pre-treatment with electroacupuncture (EA) or APETx2 can attenuate mechanical hyperalgesia in this murine model remains unknown. METHODS Accordingly, we examined the analgesic effect of EA in a murine model of FM pain induced by dual injections of acid saline and investigated whether EA or APETx2 can attenuate FM pain via the ASIC3 channel. RESULTS EA significantly reduced mechanical hyperalgesia in this model. ASIC3 antagonism, induced by injecting APETx2, also significantly reduced mechanical hyperalgesia. The expression of ASIC3 in the dorsal root ganglia, spinal cord and thalamus was increased after FM model induction. Over-expression of these nociceptive channels was attenuated by pre-treatment with EA or an ASIC3 antagonist. CONCLUSION Our data reveal that both EA and ASIC3 blockade significantly reduce FM pain in mice via the ASIC3, Nav1.7 and Nav1.8 signalling pathways. Moreover, our findings support the potential clinical use of EA for the treatment of FM pain.
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Affiliation(s)
- Liang-Ta Yen
- College of Chinese Medicine, Graduate Institute of Acupuncture Science, 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.,Department of Chinese Medicine, China Medical University Hospital, Taichung, Taiwan
| | - Hsin-Cheng Hsu
- College of Chinese Medicine, School of Post-Baccalaureate Chinese Medicine, China Medical University, Taichung, Taiwan
| | - Yi-Wen Lin
- College of Chinese Medicine, Graduate Institute of Acupuncture Science, China Medical University, Taichung, Taiwan.,College of Chinese Medicine, School of Post-Baccalaureate Chinese Medicine, China Medical University, Taichung, Taiwan.,Master's Program for Traditional Chinese Veterinary Medicine.,Research Center for Chinese Medicine and Acupuncture, China Medical University, Taichung, Taiwan
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13
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Zhang Y, Huang L, Kozlov SA, Rubini P, Tang Y, Illes P. Acupuncture alleviates acid- and purine-induced pain in rodents. Br J Pharmacol 2019; 177:77-92. [PMID: 31444978 DOI: 10.1111/bph.14847] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 08/12/2019] [Accepted: 08/14/2019] [Indexed: 12/14/2022] Open
Affiliation(s)
- Ying Zhang
- Acupuncture and Tuina School, Chengdu University of TCM, Chengdu, China
| | - Lumei Huang
- Acupuncture and Tuina School, Chengdu University of TCM, Chengdu, China
| | - Sergey A Kozlov
- Shemyakin-Ovchinikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Patrizia Rubini
- Acupuncture and Tuina School, Chengdu University of TCM, Chengdu, China
| | - Yong Tang
- Acupuncture and Tuina School, Chengdu University of TCM, Chengdu, China
| | - Peter Illes
- Acupuncture and Tuina School, Chengdu University of TCM, Chengdu, China.,Rudolf-Boehm-Institut für Pharmakologie und Toxikologie, Universität Leipzig, Leipzig, Germany
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14
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Pitake S, Middleton LJ, Abdus-Saboor I, Mishra SK. Inflammation Induced Sensory Nerve Growth and Pain Hypersensitivity Requires the N-Type Calcium Channel Cav2.2. Front Neurosci 2019; 13:1009. [PMID: 31607850 PMCID: PMC6761232 DOI: 10.3389/fnins.2019.01009] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 09/05/2019] [Indexed: 12/26/2022] Open
Abstract
Voltage-gated calcium channels (VGCCs) are important mediators of pain hypersensitivity during inflammatory states, but their role in sensory nerve growth remains underexplored. Here, we assess the role of the N-type calcium channel Cav2.2 in the complete Freund’s adjuvant (CFA) model of inflammatory pain. We demonstrate with in situ hybridization and immunoblotting, an increase in Cav2.2 expression after hind paw CFA injection in sensory neurons that respond to thermal stimuli, but not in two different mechanosensitive neuronal populations. Further, Cav2.2 upregulation post-CFA correlates with thermal but not mechanical hyperalgesia in behaving mice, and this hypersensitivity is blocked with a specific Cav2.2 inhibitor. Voltage clamp recordings reveal a significant increase in Cav2.2 currents post-CFA, while current clamp analyses demonstrate a significant increase in action potential frequency. Moreover, CFA-induced sensory nerve growth, which involves the extracellular signal-related kinase (ERK1/2) signaling pathway and likely contributes to inflammation-induced hyperalgesia, was blocked with the Cav2.2 inhibitor. Together, this work uncovers a role for Cav2.2 during inflammation, demonstrating that VGCC activity can promote thermal hyperalgesia through both changes in firing rates of sensory neurons as well as promotion of new neurite outgrowth.
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Affiliation(s)
- Saumitra Pitake
- Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, United States.,Department of Biology, University of Pennsylvania, Philadelphia, PA, United States
| | - Leah J Middleton
- Department of Biology, University of Pennsylvania, Philadelphia, PA, United States
| | - Ishmail Abdus-Saboor
- Department of Biology, University of Pennsylvania, Philadelphia, PA, United States
| | - Santosh K Mishra
- Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, United States.,Comparative Medicine Institute, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, United States.,The W.M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, United States.,Program in Genetics, North Carolina State University, Raleigh, NC, United States
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15
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Hsu HC, Hsieh CL, Wu SY, Lin YW. Toll-like receptor 2 plays an essential role in electroacupuncture analgesia in a mouse model of inflammatory pain. Acupunct Med 2019; 37:356-364. [PMID: 31517506 DOI: 10.1136/acupmed-2017-011469] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Inflammatory pain occurs when local tissue injury activates macrophages and neutrophils, hence increasing pro-inflammatory cytokine and chemokine levels. Toll-like receptor 2 (TLR2) antagonism reportedly suppresses neuropathic and inflammatory pain. AIMS In the present study, we investigated the effect of electroacupuncture (EA) on TLR2 and related signalling molecules in a complete Freund's adjuvant (CFA)-induced mouse model of inflammatory pain to determine whether EA can attenuate inflammatory pain via the TLR2 signalling pathway. METHODS EA significantly reduced mechanical and thermal hyperalgesia in the animal model. A similar effect was produced by TLR2 antagonism induced by CU-CPT22 injection. RESULTS TLR2 expression in the dorsal root ganglia, spinal cord and thalamus increased following induction of inflammation. Expression levels of downstream molecules such as pPI3K, pAkt and pmTOR also increased, as did those of MAPK subfamily members such as pERK, pp38 and pJNK. Transcription factors (pCREB and pNFκB) and nociceptive ion channels (Nav1.7 and Nav1.8) were also involved. CONCLUSION Increased expression of the above molecules was attenuated by both EA and TLR2 antagonism. Our results show that EA attenuates inflammatory pain via TLR2 signalling.
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Affiliation(s)
- Hsin-Cheng Hsu
- School of Post-Baccalaureate Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan
| | - Ching-Liang Hsieh
- Graduate Institute of Acupuncture Science, College of Chinese Medicine, China Medical University, Taichung, Taiwan.,Graduate Institute of Integrated Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan
| | - Shu-Yih Wu
- Department of Rehabilitation Medicine, Mackay Memorial Hospital, Taipei, Taiwan
| | - Yi-Wen Lin
- School of Post-Baccalaureate Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan.,Graduate Institute of Acupuncture Science, College of Chinese Medicine, China Medical University, Taichung, Taiwan.,Research Center for Chinese Medicine & Acupuncture, China Medical University, Taichung, Taiwan
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16
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Islet-cell autoantigen 69 mediates the antihyperalgesic effects of electroacupuncture on inflammatory pain by regulating spinal glutamate receptor subunit 2 phosphorylation through protein interacting with C-kinase 1 in mice. Pain 2019; 160:712-723. [PMID: 30699097 PMCID: PMC6407810 DOI: 10.1097/j.pain.0000000000001450] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Supplemental Digital Content is Available in the Text. A clear role of ICA69 in mediating the antihyperalgesic effects of electroacupuncture was confirmed, and the ICA69-PICK1-GluR2 molecular mechanism to explain these effects is proposed. Electroacupuncture (EA) is widely used in clinical settings to reduce inflammatory pain. Islet-cell autoantigen 69 (ICA69) has been reported to regulate long-lasting hyperalgesia in mice. ICA69 knockout led to reduced protein interacting with C-kinase 1 (PICK1) expression and increased glutamate receptor subunit 2 (GluR2) phosphorylation at Ser880 in spinal dorsal horn. In this study, we evaluated the role of ICA69 in the antihyperalgesic effects of EA and the underlying mechanism through regulation of GluR2 and PICK1 in spinal dorsal horn. Hyperalgesia was induced in mice with subcutaneous plantar injection of complete Freund adjuvant (CFA) to cause inflammatory pain. Electroacupuncture was then applied for 30 minutes every other day after CFA injection. When compared with CFA group, paw withdrawal frequency of CFA+EA group was significantly decreased. Remarkable increases in Ica1 mRNA expression and ICA69 protein levels on the ipsilateral side were detected in the CFA+EA group. ICA69 expression reached the peak value around day 3. More importantly, ICA69 deletion impaired the antihyperalgesic effects of EA on GluR2-p, but PICK1 deletion could not. Injecting ICA69 peptide into the intrathecal space of ICA69-knockout mice mimicked the effects of EA analgesic and inhibited GluR2-p. Electroacupuncture had no effects on the total protein of PICK1 and GluR2. And, EA could increase the formation of ICA69-PICK1 complexes and decrease the amount of PICK1-GluR2 complexes. Our findings indicate that ICA69 mediates the antihyperalgesic effects of EA on CFA-induced inflammatory pain by regulating spinal GluR2 through PICK1 in mice.
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17
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Qiu CY, Liu TT, Wei S, Zhou YM, Wu L, Jin Y, Hu WP. TGF-β1 enhances the activity of acid-sensing ion channel in rat primary sensory neurons. J Neurosci Res 2019; 97:1298-1305. [PMID: 31240740 DOI: 10.1002/jnr.24481] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 05/27/2019] [Accepted: 05/28/2019] [Indexed: 12/20/2022]
Abstract
Transforming growth factor-β1 (TGF-β1) is an important member of multifunctional growth factor superfamily. It has been implicated in pain signaling, but little is known about the underlying mechanisms. Herein, we report that TGF-β1 can exert a sustained enhancing effect on the functional activity of acid-sensing ion channels (ASICs) in rat dorsal root ganglia (DRG) neurons. Pre-application of TGF-β1 increased the amplitude of proton-gated currents in a dose-dependent manner. Enhancement of ASIC currents lasted for more than 30 min although TGF-β1 was treated once only. This sustained enhancement by TGF-β1 could be blocked by extracellular treatment of selective TGF-β receptor I antagonist SD-208, and abolished by blockade of intracellular several non-Smad-signaling pathways. TGF-β1 also sustainedly enhanced proton-evoked spikes in rat DRG neurons. Moreover, peripheral pre-treatment with TGF-β1 dose-dependently exacerbated nociceptive behaviors evoked by intraplantar injection of acetic acid through TGF-β receptor I in rats. These results suggested that TGF-β1 potentiated ASIC-mediated electrophysiological activity and nociceptive behaviors, which revealed a novel mechanism underlying TGF-β1 implicated in peripheral pain signaling by sensitizing ASICs.
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Affiliation(s)
- Chun-Yu Qiu
- Research Center of Basic Medical Sciences, School of Basic Medical Sciences, Hubei University of Science and Technology, Xianning, P R China.,Department of Pharmacology, Hubei University of Science and Technology, Xianning, P R China
| | - Ting-Ting Liu
- Research Center of Basic Medical Sciences, School of Basic Medical Sciences, Hubei University of Science and Technology, Xianning, P R China
| | - Shuang Wei
- Research Center of Basic Medical Sciences, School of Basic Medical Sciences, Hubei University of Science and Technology, Xianning, P R China
| | - Yi-Mei Zhou
- Research Center of Basic Medical Sciences, School of Basic Medical Sciences, Hubei University of Science and Technology, Xianning, P R China
| | - Lei Wu
- Research Center of Basic Medical Sciences, School of Basic Medical Sciences, Hubei University of Science and Technology, Xianning, P R China
| | - Ying Jin
- Research Center of Basic Medical Sciences, School of Basic Medical Sciences, Hubei University of Science and Technology, Xianning, P R China
| | - Wang-Ping Hu
- Research Center of Basic Medical Sciences, School of Basic Medical Sciences, Hubei University of Science and Technology, Xianning, P R China
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18
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Wang Y, Zhao Y, Ma X, Li J, Hou J, Lv X. Beneficial Effects of Electroacupuncture on Neuropathic Pain Evoked by Spinal Cord Injury and Involvement of PI3K-mTOR Mechanisms. Biol Res Nurs 2018; 21:5-13. [PMID: 30328377 DOI: 10.1177/1099800418804896] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The purpose of this study was to examine the beneficial effects of electroacupuncture (EA) on neuropathic pain evoked by spinal cord injury (SCI) and determine the underlying molecular mechanisms of these effects. SCI was induced in rats. Behavioral tests were performed to examine pain responses induced by mechanical and thermal stimulation. Western blot analysis was used to measure the protein expression of phosphorylated mammalian target of rapamycin (p-mTOR), mTOR-mediated phosphorylated ribosomal protein S6 kinase beta-1 (p-S6K1), and phosphorylated eukaryotic translation initiation factor 4E-binding protein 1 (p-4E-BP1) in the superficial dorsal horn of the spinal cord. We showed that SCI increased the expression of p-mTOR, p-S6K1, and p-4E-BP1. The EA intervention attenuated the upregulation of mTOR signaling and alleviated mechanical and thermal pain responses in SCI rats. Blocking spinal mTOR by intrathecal injection of rapamycin also inhibited mechanical and thermal pain. In addition, blocking spinal phosphorylated phosphatidylinositide 3-kinase (p-PI3K) pathway attenuated p-mTOR pathways and mechanical and thermal hyperalgesia in SCI rats. EA also decreased the enhanced p-PI3K in the superficial dorsal horn of SCI rats. In conclusion, findings revealed specific signaling pathways that lead to neuropathic pain in response to SCI, including activation of PI3K-mTOR signaling. Further, results link the beneficial role of EA in alleviating SCI-induced neuropathic pain to its effect on these molecular mechanisms.
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Affiliation(s)
- Yujie Wang
- 1 Department of Pulmonary Medicine, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Yu Zhao
- 2 Tumor Center, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Xiaohui Ma
- 2 Tumor Center, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Jing Li
- 3 Department of Radiology, The First Hospital (Eastern Division) of Jilin University, Changchun, Jilin, China
| | - Junling Hou
- 4 Department of Neurosurgery, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Xiaohong Lv
- 1 Department of Pulmonary Medicine, The First Hospital of Jilin University, Changchun, Jilin, China
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19
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Yen LT, Hsu YC, Lin JG, Hsieh CL, Lin YW. Role of Asic3, Nav1.7 and Nav1.8 in Electroacupuncture-Induced Analgesia in a Mouse Model of Fibromyalgia Pain. Acupunct Med 2018; 36:110-116. [DOI: 10.1136/acupmed-2016-011244] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/21/2017] [Indexed: 11/04/2022]
Abstract
Background The mechanisms underlying fibromyalgia (FM) pain are not understood. The US Food and Drug Administration has recommended three drugs for treating FM—namely, pregabalin, duloxetine and milnacipran; however, these medications are associated with severe side effects. Objective To create a mouse model of FM pain using dual injections of acidic saline to cause mechanical hyperalgesia and test whether ASIC3, Nav1.7 and Nav1.8 are involved in this process and whether electroacupuncture (EA) can reverse these phenomena. Methods The FM model was established by injecting acidic saline twice into 40 ICR mice. The mice were assigned to subgroups (n=8 each) treated with different EA frequencies (2, 15 and 50 Hz). ASIC3, Nav1.7 and Nav1.8 expression levels were measured by Western blotting and immunohistochemistry. Results Significant mechanical hyperalgesia was induced on day 8 in FM mice, which was reversed by 2, 15 and 50 Hz EA. ASIC3, Nav1.7 and Nav1.8 protein levels increased significantly in both the dorsal root ganglion and in the spinal cord of FM model mice. These changes were further attenuated by 2, 15 and 50 Hz EA. Conclusion Reduced nociceptive ASIC3, Nav1.7 and Nav1.8 proteins are involved in the preventive effects of EA against FM, and this series of molecules may represent targets for FM treatment.
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Affiliation(s)
- Liang-Ta Yen
- College of Chinese Medicine, Graduate Institute of Acupuncture Science, China Medical University, Taichung, Taiwan
| | - Yu-Chan Hsu
- College of Chinese Medicine, Graduate Institute of Acupuncture Science, China Medical University, Taichung, Taiwan
| | - Jaung-Geng Lin
- College of Chinese Medicine, School of Chinese Medicine, China Medical University, Taichung, USA
| | - Ching-Liang Hsieh
- Department of Chinese Medicine, China Medical University Hospital, Taichung, Taiwan
- Graduate Institute of Acupuncture Science, Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan
| | - Yi-Wen Lin
- College of Chinese Medicine, Graduate Institute of Acupuncture Science, China Medical University, Taichung, Taiwan
- College of Chinese Medicine, School of Post-Baccalaureate Chinese Medicine, China Medical University, Taichung, Taiwan
- Master's Program for Traditional Chinese Veterinary Medicine, Taichung, Taiwan
- Research Center for Chinese Medicine & Acupuncture, China Medical University, Taichung, Taiwan
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20
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Tian D, Tian M, Zhang L, Zhao P, Cui Y, Li J. High fat diet sensitizes fibromyalgia-like pain behaviors in mice via tumor necrosis factor alpha. PLoS One 2018; 13:e0190861. [PMID: 29444083 PMCID: PMC5812560 DOI: 10.1371/journal.pone.0190861] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 12/21/2017] [Indexed: 12/21/2022] Open
Abstract
Fibromyalgia (FM) and obesity are closely related. However, little is known about how obesity contributes to FM. Importantly, adequate evidence has shown that tumor necrosis factor alpha (TNF-α) plays a critical role in obesity. Thus, we hypothesized that obesity-induced TNF-α release may potentiate FM-associated pain. To test this hypothesis, we investigated the role of TNF-α in the development of FM-like pain in a mouse model of acid saline injection-induced FM. Consistent with previous reports, we showed that repeated acid saline injections induced bilateral mechanical hyperalgesia, and this effect lasted for at least 4 days after acid saline injections. This phenomenon was associated with increased levels of TNF-α in plasma, muscles, and spinal cord. Furthermore, we found that 24 weeks of high fat diet treatment significantly potentiated acid saline-induced bilateral mechanical hyperalgesia. High fat diet-treated mice exhibited robustly increased levels of TNF-α in plasma, muscles, and spinal cord after acid saline injections compared with low fat diet-treated mice. Additionally, using immunofluorescence staining, we found that the number of TNF-α positive cells in dorsal root ganglion (DRG) was increased after acid saline injections, and high fat diet treatment further sensitized this increase. Finally, we reported that acid saline-induced FM-like pain behaviors were abolished in TNFRp55-/- mice, confirming the critical role of TNF-α in the development of FM-like pain. Taken together, our results suggested that high fat diet treatment may sensitize acid saline-induced FM-like pain via increasing TNF-α levels in plasma, muscles, and DRG.
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Affiliation(s)
- Dan Tian
- Department of Anesthesiology, Second hospital of Jilin University, Changchun, China
| | - Miao Tian
- Department of Gynecology, Second hospital of Jilin University, Changchun, China
| | - Leilei Zhang
- Department of Anesthesiology, Second hospital of Jilin University, Changchun, China
| | - Peng Zhao
- Department of Anesthesiology, Second hospital of Jilin University, Changchun, China
| | - Yunfeng Cui
- Department of Anesthesiology, Second hospital of Jilin University, Changchun, China
| | - Jinlong Li
- Department of Gastrointestinal Surgery, Second hospital of Jilin University, Changchun, China
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Targeting ASIC3 for Relieving Mice Fibromyalgia Pain: Roles of Electroacupuncture, Opioid, and Adenosine. Sci Rep 2017; 7:46663. [PMID: 28440280 PMCID: PMC5404229 DOI: 10.1038/srep46663] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 03/21/2017] [Indexed: 01/19/2023] Open
Abstract
Many scientists are seeking better therapies for treating fibromyalgia (FM) pain. We used a mouse model of FM to determine if ASIC3 and its relevant signaling pathway participated in FM pain. We demonstrated that FM-induced mechanical hyperalgesia was attenuated by electroacupuncture (EA). The decrease in fatigue-induced lower motor function in FM mice was also reversed by EA. These EA-based effects were abolished by the opioid receptor antagonist naloxone and the adenosine A1 receptor antagonist rolofylline. Administration of opioid receptor agonist endomorphin (EM) or adenosine A1 receptor agonist N6-cyclopentyladenosine (CPA) has similar results to EA. Similar results were also observed in ASIC3−/− or ASIC3 antagonist (APETx2) injected mice. Using western blotting, we determined that pPKA, pPI3K, and pERK were increased during a dual acidic injection priming period. Nociceptive receptors, such as ASIC3, Nav1.7, and Nav1.8, were upregulated in the dorsal root ganglion (DRG) and spinal cord (SC) of FM mice. Furthermore, pPKA, pPI3K, and pERK were increased in the central thalamus. These aforementioned mechanisms were completely abolished in ASIC3 knockout mice. Electrophysiological results also indicated that acid potentiated Nav currents through ASIC3 and ERK pathway. Our results highlight the crucial role of ASIC3-mediated mechanisms in the treatment of FM-induced mechanical hyperalgesia.
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Enhancement of immune cytokines and splenic CD4+ T cells by electroacupuncture at ST36 acupoint of SD rats. PLoS One 2017; 12:e0175568. [PMID: 28406959 PMCID: PMC5391063 DOI: 10.1371/journal.pone.0175568] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2016] [Accepted: 03/28/2017] [Indexed: 01/08/2023] Open
Abstract
Electroacupuncture at the ST36 acupoint can enhance the body’s immune function. However, the mechanism for this enhancement has not been fully described. Our study was designed to investigate the effect of electroacupuncture on the immune function of Sprague-Dawley (SD) rats. The rats were randomly divided into three groups: a control group, a non-acupoint group (abdominal muscle acupuntured) and a ST36 acupoint group. Our results showed that successive electroacupuncture at the ST36 acupoint for 3 d significantly enhanced the interferon-γ (IFN-γ) level in the serum of SD rats. The results also showed that the serum and extracts from spleen cells of the ST36 acupoint group contained higher levels of interleukin (IL)-2 and IL-17 compared to those of the other two groups. Immunohistochemical analysis showed that electroacupuncture applied to the ST36 acupoint enhanced the expression level of CD4 in spleen cells. Furthermore, it was observed that CD4 co-localized with transient receptor potential vanilloid (TRPV) channels at the membrane of splenic CD4+ T cells and the expression level of CD4 was related to TRPV channels in the electroacupuncture treatment. These observations indicated that electroacupuncture stimulation at the ST36 acupoint enhanced the level of immune cytokines and splenic CD4+ T cells through TRPV channels in this system.
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Fu H, Fang P, Zhou HY, Zhou J, Yu XW, Ni M, Zheng JY, Jin Y, Chen JG, Wang F, Hu ZL. Acid-sensing ion channels in trigeminal ganglion neurons innervating the orofacial region contribute to orofacial inflammatory pain. Clin Exp Pharmacol Physiol 2016; 43:193-202. [PMID: 26510178 DOI: 10.1111/1440-1681.12510] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 10/21/2015] [Accepted: 10/22/2015] [Indexed: 12/31/2022]
Abstract
Orofacial pain is a common clinical symptom that is accompanied by tooth pain, migraine and gingivitis. Accumulating evidence suggests that acid-sensing ion channels (ASICs), especially ASIC3, can profoundly affect the physiological properties of nociception in peripheral sensory neurons. The aim of this study is to examine the contribution of ASICs in trigeminal ganglion (TG) neurons to orofacial inflammatory pain. A Western blot (WB), immunofluorescence assay of labelled trigeminal ganglion neurons, orofacial formalin test, cell preparation and electrophysiological experiments are performed. This study demonstrated that ASIC1, ASIC2a and ASIC3 are highly expressed in TG neurons innervating the orofacial region of rats. The amplitude of ASIC currents in these neurons increased 119.72% (for ASIC1-like current) and 230.59% (for ASIC3-like current) in the formalin-induced orofacial inflammatory pain model. In addition, WB and immunofluorescence assay demonstrated a significantly augmented expression of ASICs in orofacial TG neurons during orofacial inflammation compared with the control group. The relative protein density of ASIC1, ASIC2a and ASIC3 also increased 58.82 ± 8.92%, 45.30 ± 11.42% and 55.32 ± 14.71%, respectively, compared with the control group. Furthermore, pharmacological blockade of ASICs and genetic deletion of ASIC1 attenuated the inflammation response. These findings indicate that peripheral inflammation can induce the upregulation of ASICs in TG neurons, causing orofacial inflammatory pain. Additionally, the specific inhibitor of ASICs may have a significant analgesic effect on orofacial inflammatory pain.
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Affiliation(s)
- Hui Fu
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei.,Department of Pharmacology, Guangdong Medical College, Dongguan, China
| | - Peng Fang
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei
| | - Hai-Yun Zhou
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei
| | - Jun Zhou
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei
| | - Xiao-Wei Yu
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei
| | - Ming Ni
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei
| | - Jie-Yan Zheng
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei
| | - You Jin
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei.,The Key Laboratory of Neurological Diseases (HUST), Ministry of Education of China, Wuhan, Hubei.,The Key Laboratory for Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan, Hubei
| | - Jian-Guo Chen
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei.,The Key Laboratory of Neurological Diseases (HUST), Ministry of Education of China, Wuhan, Hubei.,The Key Laboratory for Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan, Hubei
| | - Fang Wang
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei.,The Key Laboratory of Neurological Diseases (HUST), Ministry of Education of China, Wuhan, Hubei.,The Key Laboratory for Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan, Hubei
| | - Zhuang-Li Hu
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei.,The Key Laboratory of Neurological Diseases (HUST), Ministry of Education of China, Wuhan, Hubei.,The Key Laboratory for Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan, Hubei
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Gao M, Long H, Ma W, Liao L, Yang X, Zhou Y, Shan D, Huang R, Jian F, Wang Y, Lai W. The role of periodontal ASIC3 in orofacial pain induced by experimental tooth movement in rats. Eur J Orthod 2015; 38:577-583. [DOI: 10.1093/ejo/cjv082] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Mediators, Receptors, and Signalling Pathways in the Anti-Inflammatory and Antihyperalgesic Effects of Acupuncture. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2015; 2015:975632. [PMID: 26339274 PMCID: PMC4539069 DOI: 10.1155/2015/975632] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 03/30/2015] [Indexed: 12/21/2022]
Abstract
Acupuncture has been used for millennia to treat allergic diseases including both intermittent rhinitis and persistent rhinitis. Besides the research on the efficacy and safety of acupuncture treatment for allergic rhinitis, research has also investigated how acupuncture might modulate immune function to exert anti-inflammatory effects. A proposed model has previously hypothesized that acupuncture might downregulate proinflammatory neuropeptides, proinflammatory cytokines, and neurotrophins, modulating transient receptor potential vallinoid (TRPV1), a G-protein coupled receptor which plays a central role in allergic rhinitis. Recent research has been largely supportive of this model. New advances in research include the discovery of a novel cholinergic anti-inflammatory pathway activated by acupuncture. A chemokine-mediated proliferation of opioid-containing macrophages in inflamed tissues, in response to acupuncture, has also been demonstrated for the first time. Further research on the complex cross talk between receptors during inflammation is also helping to elucidate the mediators and signalling pathways activated by acupuncture.
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Analgesic Effect of Electroacupuncture in a Mouse Fibromyalgia Model: Roles of TRPV1, TRPV4, and pERK. PLoS One 2015; 10:e0128037. [PMID: 26043006 PMCID: PMC4456150 DOI: 10.1371/journal.pone.0128037] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 04/21/2015] [Indexed: 11/19/2022] Open
Abstract
Fibromyalgia (FM) is among the most common chronic pain syndromes encountered in clinical practice, but there is limited understanding of FM pathogenesis. We examined the contribution of transient receptor potential vanilloid 1 (TRPV1) and TRPV4 channels to chronic pain in the repeated acid injection mouse model of FM and the potential therapeutic efficacy of electroacupuncture. Electroacupuncture (EA) at the bilateral Zusanli (ST36) acupoint reduced the long-lasting mechanical hyperalgesia induced by repeated acid saline (pH 4) injection in mouse hindpaw. Isolated L5 dorsal root ganglion (DRG) neurons from FM model mice (FM group) were hyperexcitable, an effect reversed by EA pretreatment (FM + EA group). The increase in mechanical hyperalgesia was also accompanied by upregulation of TRPV1 expression and phosphoactivation of extracellular signal regulated kinase (pERK) in the DRG, whereas DRG expression levels of TRPV4, p-p38, and p-JNK were unaltered. Blockade of TRPV1, which was achieved using TRPV1 knockout mice or via antagonist injection, and pERK suppressed development of FM-like pain. Both TRPV1 and TRPV4 protein expression levels were increased in the spinal cord (SC) of model mice, and EA at the ST36 acupoint decreased overexpression. This study strongly suggests that DRG TRPV1 overexpression and pERK signaling, as well as SC TRPV1 and TRPV4 overexpression, mediate hyperalgesia in a mouse FM pain model. The therapeutic efficacy of EA may result from the reversal of these changes in pain transmission pathways.
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Qiu F, Qiu CY, Cai H, Liu TT, Qu ZW, Yang Z, Li JD, Zhou QY, Hu WP. Oxytocin inhibits the activity of acid-sensing ion channels through the vasopressin, V1A receptor in primary sensory neurons. Br J Pharmacol 2015; 171:3065-76. [PMID: 24641084 DOI: 10.1111/bph.12635] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 01/01/2014] [Accepted: 02/04/2014] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND AND PURPOSE A growing number of studies have demonstrated that oxytocin (OT) plays an analgesic role in modulation of nociception and pain. Most work to date has focused on the central mechanisms of OT analgesia, but little is known about whether peripheral mechanisms are also involved. Acid-sensing ion channels (ASICs) are distributed in peripheral sensory neurons and participate in nociception. Here, we investigated the effects of OT on the activity of ASICs in dorsal root ganglion (DRG) neurons. EXPERIMENTAL APPROACH Electrophysiological experiments were performed on neurons from rat DRG. Nociceptive behaviour was induced by acetic acid in rats and mice lacking vasopressin, V1A receptors. KEY RESULTS OT inhibited the functional activity of native ASICs. Firstly, OT dose-dependently decreased the amplitude of ASIC currents in DRG neurons. Secondly, OT inhibition of ASIC currents was mimicked by arginine vasopressin (AVP) and completely blocked by the V1A receptor antagonist SR49059, but not by the OT receptor antagonist L-368899. Thirdly, OT altered acidosis-evoked membrane excitability of DRG neurons and significantly decreased the amplitude of the depolarization and number of action potentials induced by acid stimuli. Finally, peripherally administered OT or AVP inhibited nociceptive responses to intraplantar injection of acetic acid in rats. Both OT and AVP also induced an analgesic effect on acidosis-evoked pain in wild-type mice, but not in V1A receptor knockout mice. CONCLUSIONS AND IMPLICATIONS These results reveal a novel peripheral mechanism for the analgesic effect of OT involving the modulation of native ASICs in primary sensory neurons mediated by V1A receptors.
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Affiliation(s)
- Fang Qiu
- Department of Pharmacology, Hubei University of Science and Technology, Xianning, China; College of Life Sciences, Hubei University, Wuhan, China
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Martínez-Rojas VA, Barragán-Iglesias P, Rocha-González HI, Murbartián J, Granados-Soto V. Role of TRPV1 and ASIC3 in formalin-induced secondary allodynia and hyperalgesia. Pharmacol Rep 2014; 66:964-71. [PMID: 25443722 DOI: 10.1016/j.pharep.2014.06.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 04/02/2014] [Accepted: 06/05/2014] [Indexed: 01/18/2023]
Abstract
BACKGROUND In the present study we determined the role of transient receptor potential V1 channel (TRPV1) and acid-sensing ion channel 3 (ASIC3) in chronic nociception. METHODS 1% formalin was used to produce long-lasting secondary allodynia and hyperalgesia in rats. Western blot was used to determine TRPV1 and ASIC3 expression in dorsal root ganglia. RESULTS Peripheral ipsilateral, but not contralateral, pre-treatment (-10min) with the TRPV1 receptor antagonists capsazepine (0.03-0.3μM/paw) and A-784168 (0.01-1μM/paw) prevented 1% formalin-induced secondary mechanical allodynia and hyperalgesia in the ipsilateral and contralateral paws. Likewise, peripheral ipsilateral, but not contralateral, pre-treatment with the non-selective and selective ASIC3 blocker benzamil (0.1-10μM/paw) and APETx2 (0.02-2μM/paw), respectively, prevented 1% formalin-induced secondary mechanical allodynia and hyperalgesia in both paws. Peripheral ipsilateral post-treatment (day 6 after formalin injection) with capsazepine (0.03-0.3μM/paw) and A-784168 (0.01-1μM/paw) reversed 1% formalin-induced secondary mechanical allodynia and hyperalgesia in both paws. In addition, peripheral ipsilateral post-treatment with benzamil (0.1-10μM/paw) and APETx2 (0.02-2μM/paw), respectively, reversed 1% formalin-induced secondary mechanical allodynia and hyperalgesia in both paws. TRPV1 and ASIC3 proteins were expressed in dorsal root ganglion in normal conditions, and 1% formalin injection increased expression of both proteins in this location at 1 and 6 days compared to naive rats. CONCLUSIONS Data suggest that TRPV1 and ASIC3 participate in the development and maintenance of long-lasting secondary allodynia and hyperalgesia induced by formalin in rats. The use of TRPV1 and ASIC3 antagonists by peripheral administration could prove useful to treat chronic pain.
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Affiliation(s)
- Vladimir A Martínez-Rojas
- Neurobiology of Pain Laboratory, Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados (Cinvestav), Sede Sur., México, D.F., Mexico
| | - Paulino Barragán-Iglesias
- Neurobiology of Pain Laboratory, Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados (Cinvestav), Sede Sur., México, D.F., Mexico
| | - Héctor I Rocha-González
- Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, México, D.F., Mexico
| | - Janet Murbartián
- Neurobiology of Pain Laboratory, Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados (Cinvestav), Sede Sur., México, D.F., Mexico
| | - Vinicio Granados-Soto
- Neurobiology of Pain Laboratory, Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados (Cinvestav), Sede Sur., México, D.F., Mexico.
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Abundant expression and functional participation of TRPV1 at Zusanli acupoint (ST36) in mice: mechanosensitive TRPV1 as an "acupuncture-responding channel". BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2014; 14:96. [PMID: 24612851 PMCID: PMC3984709 DOI: 10.1186/1472-6882-14-96] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 02/13/2014] [Indexed: 02/07/2023]
Abstract
Background Acupuncture is a therapy that involves applying mechanical stimulation to acupoints using needles. Although acupuncture is believed to trigger neural regulation by opioids or adenosine, still little is known about how physical stimulation is turned into neurological signaling. The transient receptor potential vanilloid receptors 1 and 4 (TRPV1 and TRPV4) and the acid-sensing ion channel 3 (ASIC3) are regarded as mechanosensitive channels. This study aimed to clarify their role at the Zusanli acupoint (ST36) and propose possible sensing pathways linking channel activation to neurological signaling. Methods First, tissues from different anatomical layers of ST36 and the sham point were sampled, and channel expressions between the two points were compared using western blotting. Second, immunofluorescence was performed at ST36 to reveal distribution pattern of the channels. Third, agonist of the channels were injected into ST36 and tested in a mouse inflammatory pain model to seek if agonist injection could replicate acupuncture-like analgesic effect. Last, the components of proposed downstream sensing pathway were tested with western blotting to determine if they were expressed in tissues with positive mechanosensitive channel expression. Results The results from western blotting demonstrated an abundance of TRPV1, TRPV4, and ASIC3 in anatomical layers of ST36. Furthermore, immunofluorescence showed these channels were expressed in both neural and non-neural cells at ST36. However, only capsaicin, a TRPV1 agonist, replicated the analgesic effect of acupuncture when injected into ST36. Components of calcium wave propagation (CWP, the proposed downstream sensing pathway) were also expressed in tissues with abundant TRPV1 expression, the muscle and epimysium layers. Conclusions The results demonstrated mechanosensitive channel TRPV1 is highly expressed at ST36 and possibly participated in acupuncture related analgesia. Since CWP was reported by other to occur during acupuncture and its components were shown here to express in tissues with positive TRPV1 expression. These findings suggest TRPV1 might act as acupuncture-responding channel by sensing physical stimulation from acupuncture and conducting the signaling via CWP to nerve terminals. This study provided a better understanding between physical stimulation from acupuncture to neurological signaling.
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Abstract
In the last decade, preclinical investigations of electroacupuncture mechanisms on persistent tissue injury (inflammatory), nerve injury (neuropathic), cancer, and visceral pain have increased. These studies show that electroacupuncture activates the nervous system differently in health than in pain conditions, alleviates both sensory and affective inflammatory pain, and inhibits inflammatory and neuropathic pain more effectively at 2 to 10 Hz than at 100 Hz. Electroacupuncture blocks pain by activating a variety of bioactive chemicals through peripheral, spinal, and supraspinal mechanisms. These include opioids, which desensitize peripheral nociceptors and reduce proinflammatory cytokines peripherally and in the spinal cord, and serotonin and norepinephrine, which decrease spinal N-methyl-D-aspartate receptor subunit GluN1 phosphorylation. Additional studies suggest that electroacupuncture, when combined with low dosages of conventional analgesics, provides effective pain management which can forestall the side effects of often-debilitating pharmaceuticals.
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Affiliation(s)
- Ruixin Zhang
- Assistant Professor, Center for Integrative Medicine, School of Medicine, University of Maryland, Baltimore, Maryland
| | - Lixing Lao
- Professor, Center for Integrative Medicine, School of Medicine, University of Maryland, Baltimore, Maryland
| | - Ke Ren
- Professor, Department of Neural and Pain Sciences, Dental School, University of Maryland, Baltimore, Maryland
| | - Brian M. Berman
- Professor, Center for Integrative Medicine, School of Medicine, University of Maryland, Baltimore, Maryland
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Guo BL, Sui BD, Wang XY, Wei YY, Huang J, Chen J, Wu SX, Li YQ, Wang YY, Yang YL. Significant changes in mitochondrial distribution in different pain models of mice. Mitochondrion 2013; 13:292-7. [DOI: 10.1016/j.mito.2013.03.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Revised: 02/23/2013] [Accepted: 03/19/2013] [Indexed: 11/25/2022]
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Dang K, Bielefeldt K, Gebhart GF. Cyclophosphamide-induced cystitis reduces ASIC channel but enhances TRPV1 receptor function in rat bladder sensory neurons. J Neurophysiol 2013; 110:408-17. [PMID: 23636721 DOI: 10.1152/jn.00945.2012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Using patch-clamp techniques, we studied the plasticity of acid-sensing ion channels (ASIC) and transient receptor potential V1 (TRPV1) channel function in dorsal root ganglia (DRG) neurons retrogradely labeled from the bladder. Saline (control) or cyclophosphamide (CYP) was given intraperitoneally on days 1, 3, and 5. On day 6, lumbosacral (LS, L6-S2) or thoracolumbar (TL, T13-L2) DRG were removed and dissociated. Bladders and bladder DRG neurons from CYP-treated rats showed signs of inflammation (greater myeloperoxidase activity; lower intramuscular wall pH) and increased size (whole cell capacitance), respectively, compared with controls. Most bladder neurons (>90%) responded to protons and capsaicin. Protons produced multiphasic currents with distinct kinetics, whereas capsaicin always triggered a sustained response. The TRPV1 receptor antagonist A-425619 abolished capsaicin-triggered currents and raised the threshold of heat-activated currents. Prolonged exposure to an acidic environment (pH range: 7.2 to 6.6) inhibited proton-evoked currents, potentiated the capsaicin-evoked current, and reduced the threshold of heat-activated currents in LS and TL bladder neurons. CYP treatment reduced density but not kinetics of all current components triggered by pH 5. In contrast, CYP-treatment was associated with an increased current density in response to capsaicin in LS and TL bladder neurons. Correspondingly, heat triggered current at a significantly lower temperature in bladder neurons from CYP-treated rats compared with controls. These results reveal that cystitis differentially affects TRPV1- and ASIC-mediated currents in both bladder sensory pathways. Acidification of the bladder wall during inflammation may contribute to changes in nociceptive transmission mediated through the TRPV1 receptor, suggesting a role for TRPV1 in hypersensitivity associated with cystitis.
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Affiliation(s)
- Khoa Dang
- Department of Pharmacology, Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
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Serotonin facilitates peripheral pain sensitivity in a manner that depends on the nonproton ligand sensing domain of ASIC3 channel. J Neurosci 2013; 33:4265-79. [PMID: 23467344 DOI: 10.1523/jneurosci.3376-12.2013] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Tissue acidosis and inflammatory mediators play critical roles in inflammatory pain. Extracellular acidosis activates acid-sensing ion channels (ASICs), which have emerged as key sensors for extracellular protons in the central and peripheral nervous systems and play key roles in pain sensation and transmission. Additionally, inflammatory mediators, such as serotonin (5-HT), are known to enhance pain sensation. However, functional interactions among protons, inflammatory mediators, and ASICs in pain sensation are poorly understood. In the present study, we show that 5-HT, a classical pro-inflammatory mediator, specifically enhances the proton-evoked sustained, but not transient, currents mediated by homomeric ASIC3 channels and heteromeric ASIC3/1a and ASIC3/1b channels. Unexpectedly, the effect of 5-HT on ASIC3 channels does not involve activation of 5-HT receptors, but is mediated via a functional interaction between 5-HT and ASIC3 channels. We further show that the effect of 5-HT on ASIC3 channels depends on the newly identified nonproton ligand sensing domain. Finally, coapplication of 5-HT and acid significantly increased pain-related behaviors as assayed by the paw-licking test in mice, which was largely attenuated in ASIC3 knock-out mice, and inhibited by the nonselective ASIC inhibitor amiloride. Together, these data identify ASIC3 channels as an unexpected molecular target for acute actions of 5-HT in inflammatory pain sensation and reveal an important role of ASIC3 channels in regulating inflammatory pain via coincident detection of extracellular protons and inflammatory mediators.
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Electroacupuncture Reduces Carrageenan- and CFA-Induced Inflammatory Pain Accompanied by Changing the Expression of Nav1.7 and Nav1.8, rather than Nav1.9, in Mice Dorsal Root Ganglia. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 2013:312184. [PMID: 23573123 PMCID: PMC3615619 DOI: 10.1155/2013/312184] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/25/2012] [Accepted: 02/13/2013] [Indexed: 11/17/2022]
Abstract
Several voltage-gated sodium channels (Navs) from nociceptive nerve fibers have been identified as important effectors in pain signaling. The objective of this study is to investigate the electroacupuncture (EA) analgesia mechanism by changing the expression of Navs in mice dorsal root ganglia (DRG). We injected carrageenan and complete Freund's adjuvant (CFA) into the mice plantar surface of the hind paw to induce inflammation and examined the antinociception effect of EA at the Zusanli (ST36) acupoint at 2 Hz low frequency. Mechanical hyperalgesia was evaluated by using electronic von Frey filaments, and thermal hyperalgesia was assessed using Hargreaves' test. Furthermore, we observed the expression and quality of Navs in DRG neurons. Our results showed that EA reduced mechanical and thermal pain in inflammatory animal model. The expression of Nav1.7 and Nav1.8 was increased after 4 days of carrageenan- and CFA-elicited inflammatory pain and further attenuated by 2 Hz EA stimulation. The attenuation cannot be observed in Nav1.9 sodium channels. We demonstrated that EA at Zusanli (ST36) acupoint at 2 Hz low-frequency stimulation attenuated inflammatory pain accompanied by decreasing the expression of Nav1.7 and 1.8, rather than Nav1.9, sodium channels in peripheral DRG neurons.
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Attenuation of TRPV1 and TRPV4 Expression and Function in Mouse Inflammatory Pain Models Using Electroacupuncture. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2012; 2012:636848. [PMID: 23258994 PMCID: PMC3520481 DOI: 10.1155/2012/636848] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 10/15/2012] [Accepted: 10/18/2012] [Indexed: 11/17/2022]
Abstract
Although pain is a major human affliction, our understanding of pain mechanisms is limited. TRPV1 (transient receptor potential vanilloid subtype 1) and TRPV4 are two crucial receptors involved in inflammatory pain, but their roles in EA- (electroacupuncture-) mediated analgesia are unknown. We injected mice with carrageenan (carra) or a complete Freund's adjuvant (CFA) to model inflammatory pain and investigated the analgesic effect of EA using animal behavior tests, immunostaining, Western blotting, and a whole-cell recording technique. The inflammatory pain model mice developed both mechanical and thermal hyperalgesia. Notably, EA at the ST36 acupoint reversed these phenomena, indicating its curative effect in inflammatory pain. The protein levels of TRPV1 and TRPV4 in DRG (dorsal root ganglion) neurons were both increased at day 4 after the initiation of inflammatory pain and were attenuated by EA, as demonstrated by immunostaining and Western blot analysis. We verified DRG electrophysiological properties to confirm that EA ameliorated peripheral nerve hyperexcitation. Our results indicated that the AP (action potential) threshold, rise time, and fall time, and the percentage and amplitude of TRPV1 and TRPV4 were altered by EA, indicating that EA has an antinociceptive role in inflammatory pain. Our results demonstrate a novel role for EA in regulating TRPV1 and TRPV4 protein expression and nerve excitation in mouse inflammatory pain models.
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