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Zhang J, Gao L, Zhang Y, Wang H, Sun S, Wu L. Involvement of microglial P2X7 receptor in pain modulation. CNS Neurosci Ther 2024; 30:e14496. [PMID: 37950524 PMCID: PMC10805404 DOI: 10.1111/cns.14496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 08/23/2023] [Accepted: 10/02/2023] [Indexed: 11/12/2023] Open
Abstract
BACKGROUND Pain is a rapid response mechanism that compels organisms to retreat from the harmful stimuli and triggers a repair response. Nonetheless, when pain persists for extended periods, it can lead to adverse changes into in the individual's brain, negatively impacting their emotional state and overall quality of life. Microglia, the resident immune cells in the central nervous system (CNS), play a pivotal role in regulating a variety of pain-related disorders. Specifically, recent studies have shed light on the central role that microglial purinergic ligand-gated ion channel 7 receptor (P2X7R) plays in regulating pain. In this respect, the P2X7R on microglial membranes represents a potential therapeutic target. AIMS To expound on the intricate link between microglial P2X7R and pain, offering insights into potential avenues for future research. METHODS We reviewed 140 literature and summarized the important role of microglial P2X7R in regulating pain, including the structure and function of P2X7R, the relationship between P2X7R and microglial polarization, P2X7R-related signaling pathways, and the effects of P2X7R antagonists on pain regulation. RESULTS P2X7R activation is related to M1 polarization of microglia, while suppressing P2X7R can transfer microglia from M1 into M2 phenotype. And targeting the P2X7R-mediated signaling pathways helps to explore new therapy for pain alleviation. P2X7R antagonists also hold potential for translational and clinical applications in pain management. CONCLUSIONS Microglial P2X7R holds promise as a potential novel pharmacological target for clinical treatments due to its distinctive structure, function, and the development of antagonists.
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Affiliation(s)
- Jing Zhang
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Department of Pediatric Dentistry, School of StomatologyThe Fourth Military Medical UniversityXi'anShaanxiChina
| | - Lei Gao
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Department of Pediatric Dentistry, School of StomatologyThe Fourth Military Medical UniversityXi'anShaanxiChina
| | - Yaoyuan Zhang
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Department of Pediatric Dentistry, School of StomatologyThe Fourth Military Medical UniversityXi'anShaanxiChina
| | - Haozhen Wang
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Department of Pediatric Dentistry, School of StomatologyThe Fourth Military Medical UniversityXi'anShaanxiChina
| | - Shukai Sun
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Department of Pediatric Dentistry, School of StomatologyThe Fourth Military Medical UniversityXi'anShaanxiChina
| | - Li‐an Wu
- State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Department of Pediatric Dentistry, School of StomatologyThe Fourth Military Medical UniversityXi'anShaanxiChina
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Feng JH, Chen K, Shen SY, Luo YF, Liu XH, Chen X, Gao W, Tong YR. The composition, pharmacological effects, related mechanisms and drug delivery of alkaloids from Corydalis yanhusuo. Biomed Pharmacother 2023; 167:115511. [PMID: 37729733 DOI: 10.1016/j.biopha.2023.115511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 09/06/2023] [Accepted: 09/12/2023] [Indexed: 09/22/2023] Open
Abstract
Corydalis yanhusuo W. T. Wang, also known as yanhusuo, yuanhu, yanhu and xuanhu, is one of the herb components of many Chinese Traditional Medicine prescriptions such as Jin Ling Zi San and Yuanhu-Zhitong priscription. C. yanhusuo was traditionally used to relieve pain and motivate blood and Qi circulation. Now there has been growing interest in pharmacological effects of alkaloids, the main bioactive components of C. yanhusuo. Eighty-four alkaloids isolated from C. yanhusuo are its important bioactive components and can be characterized into protoberberine alkaloids, aporphine alkaloids, opiate alkaloids and others and proper extraction or co-administration methods modulate their contents and efficacy. Alkaloids from C. yanhusuo have various pharmacological effects on the nervous system, cardiovascular system, cancer and others through multiple molecular mechanisms such as modulating neurotransmitters, ion channels, gut microbiota, HPA axis and signaling pathways and are potential treatments for many diseases. Plenty of novel drug delivery methods such as autologous red blood cells, self-microemulsifying drug delivery systems, nanoparticles and others have also been investigated to better exert the effects of alkaloids from C. yanhusuo. This review summarized the alkaloid components of C. yanhusuo, their pharmacological effects and mechanisms, and methods of drug delivery to lay a foundation for future investigations.
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Affiliation(s)
- Jia-Hua Feng
- School of Basic Medical Sciences, Capital Medical University, Beijing 100069, China; School of Pharmaceutical Sciences, Capital Medical University, Beijing 100069, China
| | - Kang Chen
- National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Si-Yu Shen
- School of Traditional Chinese Medicine, Capital Medical University, Beijing 100069, China
| | - Yun-Feng Luo
- School of Traditional Chinese Medicine, Capital Medical University, Beijing 100069, China
| | - Xi-Hong Liu
- School of Medicine, Henan University of Chinese Medicine, Zhengzhou 450046, China
| | - Xin Chen
- School of Basic Medical Sciences, Capital Medical University, Beijing 100069, China
| | - Wei Gao
- School of Traditional Chinese Medicine, Capital Medical University, Beijing 100069, China
| | - Yu-Ru Tong
- School of Pharmaceutical Sciences, Capital Medical University, Beijing 100069, China.
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Cheng JJ, Ma XD, Ai GX, Yu QX, Chen XY, Yan F, Li YC, Xie JH, Su ZR, Xie QF. Palmatine Protects Against MSU-Induced Gouty Arthritis via Regulating the NF-κB/NLRP3 and Nrf2 Pathways. Drug Des Devel Ther 2022; 16:2119-2132. [PMID: 35812134 PMCID: PMC9259749 DOI: 10.2147/dddt.s356307] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 06/15/2022] [Indexed: 11/29/2022] Open
Abstract
Purpose Gouty arthritis could be triggered by the deposition of monosodium uric acid (MSU) crystals. Palmatine (PAL), a protoberberine alkaloid, has been proven to possess compelling health-beneficial activities. In this study, we aimed to explore the effect of PAL on LPS plus MSU crystal-stimulated gouty arthritis in vitro and in vivo. Methods PMA-differentiated THP-1 macrophages were primed with LPS and then stimulated with MSU crystal in the presence or absence of PAL. The expression of pro-inflammatory cytokines and oxidative stress-related biomarkers and signal pathway key targets were determined by ELISA kit, Western blot, immunohistochemistry and qRT-PCR, respectively. In addition, the anti-inflammatory and antioxidant activities of PAL on MSU-induced arthritis mice were also evaluated. Results The results indicated that PAL (20, 40 and 80 μM) dose-dependently decreased the mRNA expression and levels of pro-inflammatory cytokines (interleukin-1beta (IL-1β), IL-6, IL-18 and tumor necrosis factor alpha (TNF-α)). The levels of superoxide dismutase (SOD) and glutathione (GSH) were remarkably enhanced, while the level of malondialdehyde (MDA) was reduced. Western blot analysis revealed that PAL appreciably inhibited NF-κB/NLRP3 signaling pathways through inhibiting the phosphorylation of p-65 and IκBα, blocking the expression of NLRP3, ASC, IL-1β and Caspase-1, as well as enhancing the antioxidant protein expression of Nrf2 and HO-1. In vivo, PAL attenuated MSU-induced inflammation in gouty arthritis, as evidenced by mitigating the joint swelling, and decreasing the productions of IL-1β, IL-6, IL-18, TNF-α and MDA, while enhancing the levels of SOD and GSH. Moreover, PAL further attenuated the infiltration of neutrophils into joint synovitis. Conclusion PAL protected against MSU-induced inflammation and oxidative stress via regulating the NF-κB/NLRP3 and Nrf2 pathways. PAL may represent a potential candidate for the treatment of gouty arthritis.
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Affiliation(s)
- Juan-Juan Cheng
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, 510006, People's Republic of China
| | - Xing-Dong Ma
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, 510006, People's Republic of China
| | - Gao-Xiang Ai
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, 510006, People's Republic of China
| | - Qiu-Xia Yu
- The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, 510120, People's Republic of China
| | - Xiao-Ying Chen
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, 510006, People's Republic of China
| | - Fang Yan
- The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510120, People's Republic of China.,Li Ke and Qi Yu-ru Academic Experience Inheritance Studio, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, 510006, People's Republic of China
| | - Yu-Cui Li
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, 510006, People's Republic of China
| | - Jian-Hui Xie
- The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510120, People's Republic of China.,State Key Laboratory of Dampness Syndrome of Chinese Medicine, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510120, People's Republic of China.,Guangdong Provincial Key Laboratory of Clinical Research on Traditional Chinese Medicine Syndrome, Guangzhou, 510120, People's Republic of China
| | - Zi-Ren Su
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, 510006, People's Republic of China
| | - Qing-Feng Xie
- The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510120, People's Republic of China.,Li Ke and Qi Yu-ru Academic Experience Inheritance Studio, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, 510006, People's Republic of China
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KC E, Islam J, Kim S, Kim HK, Park YS. Pain Relief in a Trigeminal Neuralgia Model via Optogenetic Inhibition on Trigeminal Ganglion Itself With Flexible Optic Fiber Cannula. Front Cell Neurosci 2022; 16:880369. [PMID: 35573830 PMCID: PMC9096083 DOI: 10.3389/fncel.2022.880369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 03/22/2022] [Indexed: 11/29/2022] Open
Abstract
The trigeminal ganglion (TG) is the primary site of aberration in trigeminal neuralgia (TN), and hence a crucial site where afferent input can be modulated. Here, we postulated that inhibiting TG via optogenetics using flexible optic cannula would diminish brainstem trigeminal nucleus caudalis (TNC) neuronal activity and pain behavior in TN rat model. Infraorbital nerve constriction was employed to induce TN in female Sprague-Dawley rats, while naive and sham rats served as controls. TG-directed microinjections of AAV virus containing either the optogenetic or null vector were delivered to rats in each group. In vivo electrophysiological responses were obtained from the ventral posteromedial nucleus (VPm) of the thalamus with simultaneous TG optogenetic stimulation using flexible optic cannula as well the effects on behavioral responses were investigated. Recordings in TN rats revealed a decrease in burst firing activity during yellow laser driven inhibition on TG, as well as considerably improved behavioral responses. In contrast, we noticed persistent hypersensitivity and increased tonic firing with blue laser stimulation which indicates that TG inhibition can synchronize trigeminal pain signal transmission in a TN animal model. The potential of an optogenetic approach in TG itself with flexible optic fiber to directly disrupt the trigeminal pain circuitry delivers fundamental underpinnings toward its prospective as a trigeminal neuralgia management.
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Affiliation(s)
- Elina KC
- Department of Medical Neuroscience, College of Medicine, Chungbuk National University, Cheongju, South Korea
| | - Jaisan Islam
- Department of Medical Neuroscience, College of Medicine, Chungbuk National University, Cheongju, South Korea
| | - Soochong Kim
- Department of Veterinary Medicine, College of Veterinary Medicine, Chungbuk National University, Cheongju, South Korea
| | - Hyong Kyu Kim
- Department of Medicine and Microbiology, College of Medicine, Chungbuk National University, Cheongju, South Korea
| | - Young Seok Park
- Department of Medical Neuroscience, College of Medicine, Chungbuk National University, Cheongju, South Korea
- Department of Neurosurgery, Chungbuk National University Hospital, Cheongju, South Korea
- *Correspondence: Young Seok Park, ;
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Pereira EWM, Heimfarth L, Santos TK, Passos FRS, Siqueira-Lima P, Scotti L, Scotti MT, Almeida JRGDS, Campos AR, Coutinho HDM, Martin P, Quintans-Júnior LJ, Quintans JSS. Limonene, a citrus monoterpene, non-complexed and complexed with hydroxypropyl-β-cyclodextrin attenuates acute and chronic orofacial nociception in rodents: Evidence for involvement of the PKA and PKC pathway. Phytomedicine 2022; 96:153893. [PMID: 35026511 DOI: 10.1016/j.phymed.2021.153893] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Revised: 12/05/2021] [Accepted: 12/11/2021] [Indexed: 06/14/2023]
Abstract
BACKGROUND Chronic orofacial pain is a serious public health problem with a prevalence of 7-11% in the population. This disorder has different etiologies and characteristics that make pharmacological treatment difficult. Natural products have been shown to be a promising source of treatments for the management of chronic pain, as an example the terpenes. PURPOSE The aim of this study was to evaluate the anti-nociceptive and anti-inflammatory effects of one of these terpenes, d-limonene (LIM - a common monoterpene found in citrus fruits) alone and complexed with hydroxypropyl-β-cyclodextrin (LIM/HPβCD) in preclinical animal models. METHODS Orofacial pain was induced by the administration of hypertonic saline on the corneal surface, the injection of formalin into the temporomandibular joint (TMJ), or chronic constriction injury of the infraorbital nerve (CCI-IoN). The study used male Wistar rats and Swiss mice treated with LIM (50 mg/kg), LIM/HPβCD (50 mg/kg), vehicle (control), gabapentin or morphine, and eyes wiping (induced by hypertonic saline), face rubbing (formalin-induced in TMJ) or mechanical hyperalgesia (provoked by CCI-IoN) were assessed. Additionally, ELISA was used to measure TNF-α, and western blot analysis to assess levels of PKAcα, NFκB, p38MAPK and phosphorylated PKC substrates. Serum levels of aspartate aminotransferase (AST) and alanine transferase (ALT) were also evaluated. RESULTS LIM and LIM/HPβCD significantly reduced (p < 0.001) corneal nociception and formalin-induced TMJ nociception. In addition, both substances attenuated (p < 0.001) mechanical hyperalgesia in the CCI-IoN model. The antinociceptive effect induced by LIM and HPβCD/LIM was associated with decreased TNF-α levels, downregulation of the NFκB and p38MAPK signalling pathways and reduced PKC substrate phosphorylation and PKA immunocontent. Moreover, the results demonstrated that complexation with HPβCD was able to decrease the therapeutic dose of LIM. CONCLUSION LIM was found to be a promising molecule for the treatment of orofacial pain due to its capacity to modulate some important mediators essential to the establishment of pain, and HPβCD can be a key tool to improve the profile of LIM.
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Affiliation(s)
- Erik W M Pereira
- Department of Physiology, Laboratory of Neuroscience and Pharmacological Assays (LANEF), Federal University of Sergipe, São Cristóvão, SE, Brazil; Health Sciences Graduate Program (PPGCS), Federal University of Sergipe, Aracaju, SE, Brazil
| | - Luana Heimfarth
- Department of Physiology, Laboratory of Neuroscience and Pharmacological Assays (LANEF), Federal University of Sergipe, São Cristóvão, SE, Brazil
| | - Tiffany Kb Santos
- Department of Physiology, Laboratory of Neuroscience and Pharmacological Assays (LANEF), Federal University of Sergipe, São Cristóvão, SE, Brazil
| | - Fabiolla R S Passos
- Department of Physiology, Laboratory of Neuroscience and Pharmacological Assays (LANEF), Federal University of Sergipe, São Cristóvão, SE, Brazil; Health Sciences Graduate Program (PPGCS), Federal University of Sergipe, Aracaju, SE, Brazil
| | | | | | | | | | - Adriana R Campos
- Experimental Biology Centre (NUBEX). University of Fortaleza, Fortaleza, CE, Brazil
| | | | - Patrick Martin
- Univ Artois, UniLaSalle, Unité Transformations & Agroressources, Béthune, France
| | - Lucindo J Quintans-Júnior
- Department of Physiology, Laboratory of Neuroscience and Pharmacological Assays (LANEF), Federal University of Sergipe, São Cristóvão, SE, Brazil; Health Sciences Graduate Program (PPGCS), Federal University of Sergipe, Aracaju, SE, Brazil
| | - Jullyana S S Quintans
- Department of Physiology, Laboratory of Neuroscience and Pharmacological Assays (LANEF), Federal University of Sergipe, São Cristóvão, SE, Brazil; Health Sciences Graduate Program (PPGCS), Federal University of Sergipe, Aracaju, SE, Brazil
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Buapratoom A, Wanasuntronwong A, Khongsombat O, Tantisira MH. Anti-nociceptive effects of ECa 233 a standardized extract of Centella asiatica (L.) Urban on chronic neuropathic orofacial pain in mice. J Ethnopharmacol 2022; 283:114737. [PMID: 34648902 DOI: 10.1016/j.jep.2021.114737] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 09/30/2021] [Accepted: 10/09/2021] [Indexed: 06/13/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE ECa 233 is a standardized extract of Centella asiatica (L.) Urban, a herb traditionally used to treat a number of diseases including neurological disorders. Accordingly, ECa 233 showed benefits on animal models of cognitive deficits, chronic stress and Parkinson's disease. Analgesic activity of ECa 233 was shown in Tail's flick test in rodent and relieving aphthous ulcer pain in man. Moreover, acute and sub-chronic toxicity testing in rodents and pharmacokinetic study in healthy volunteers, clinical trial phase I demonstrated good safety profiles of ECa 233. AIM OF THE STUDY This study aims to evaluate the anti-nociceptive effects of ECa 233 and its synergistic effect with gabapentin on chronic neuropathic orofacial pain after 3 weeks infraorbital nerve chronic constriction injury in mice. The peripheral and central nociceptive activities are also examined. MATERIALS AND METHODS Chronic neuropathic orofacial pain was induced by 3 weeks infraorbital nerve chronic constriction injury. Mice were treated with ECa 233 (30, 100 and 300 mg/kg) and gabapentin (10 mg/kg) by oral gavage starting on day 21 and going on for 14 consecutive days. Mechanical hyperalgesia and allodynia were measured on day 7, 14, 21, 28 and 35 after infraorbital nerve chronic constriction injury. At the end of the experiment, mice were observed for the sedative effect using the locomotor activity, the calcitonin gen-related peptide in trigeminal ganglion and c-fos expression in trigeminal nucleus caudalis were investigated after euthanasia. RESULTS Infraorbital nerve chronic constriction injury gradually induced marked ipsilateral mechanical hyperalgesia and allodynia. The maximum hyperalgesia and allodynia response presented on day 21 and the response was remained constant until day 35. Treatment with either 300 mg/kg ECa 233 or 10 mg/kg gabapentin were able to attenuate mechanical hyperalgesia and allodynia. The downregulation of calcitonin gen-related peptide on ipsilateral trigeminal ganglion were observed in ECa 233 at 100 and 300 mg/kg and 10 mg/kg gabapentin-treated groups. The c-fos expression on ipsilateral trigeminal nucleus caudalis was also decreased in 300 mg/kg ECa 233 and 10 mg/kg gabapentin-treated groups. CONCLUSION ECa 233 reduced hyperalgesia and allodynia by modulating the peripheral calcitonin gen-related peptide expression consequently alleviate the nociceptive activity in trigeminal nucleus caudalis. Further clinical trial to proof ECa 233's efficacy in neuropathic pain in man as well as possible attributable mechanism of action should be further investigated.
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Affiliation(s)
- Ananya Buapratoom
- Department of Physiology, Faculty of Medical Science, Naresuan University, Phitsanulok, Thailand.
| | - Aree Wanasuntronwong
- Department of Oral Biology, Faculty of Dentistry, Mahidol University, Bangkok, Thailand.
| | - Onrawee Khongsombat
- Department of Physiology, Faculty of Medical Science, Naresuan University, Phitsanulok, Thailand; The Center of Excellence for Innovation in Chemistry (PERCH-CIC), Ministry of Higher Education, Science, Research and Innovation, Thailand.
| | - Mayuree H Tantisira
- Division of Pharmacology, Faculty of Pharmaceutical Sciences, Burapha University, Chonburi, Thailand.
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Yin C, Shen W, Zhang M, Wen L, Huang R, Sun M, Gao Y, Xiong W. Inhibitory Effects of Palmatine on P2X7 Receptor Expression in Trigeminal Ganglion and Facial Pain in Trigeminal Neuralgia Rats. Front Cell Neurosci 2021; 15:672022. [PMID: 34366788 PMCID: PMC8339261 DOI: 10.3389/fncel.2021.672022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 06/01/2021] [Indexed: 11/13/2022] Open
Abstract
Trigeminal Neuralgia (TN) refers to recurrent severe paroxysmal pain in the distribution area of the trigeminal nerve, which seriously affects the quality of life of patients. This research applied the chronic constriction injury of the infraorbital nerve (CCI—ION) approach to induce an animal model of TN in rats. The mechanical pain threshold of each group of rats was determined postoperatively; the expression of P2X7 receptor in trigeminal ganglion (TG) was assessed by qRT-PCR, immunofluorescence and Western blot; and the changes of the proinflammatory cytokines IL-1β and TNF-α in serum of rats were detected by ELISA. The results showed that the administration of palmatine in the TN rats could reduce the mechanical pain threshold, significantly decrease the expression of P2X7 receptor in TG, and lower the serum concentrations of IL-1β and TNF-α, compared to the sham group. In addition, the phosphorylation level of p38 in TG of TN rats was significantly decreased after treatment with palmatine. Likewise, inhibition of P2X7 expression by shRNA treatment could effectively counteract the adversary changes of pain sensitivity, IL-1β and TNF-α production, and p38 phosphorylation in TN rats. Our data suggest that palmatine may alleviate mechanical facial pain in TN rats possibly by reducing the expression of P2X7 receptor in TG of TN rats, which may be attributable to inhibiting p38 phosphorylation and reducing the release of IL-1β and TNF-α.
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Affiliation(s)
- Cancan Yin
- Affiliated Stomatological Hospital of Nanchang University, Nanchang, China.,Hangzhou Stomatology Hospital, Hangzhou, China
| | - Wenhao Shen
- Affiliated Stomatological Hospital of Nanchang University, Nanchang, China
| | - Mingming Zhang
- Department of Physiology, Basic Medical College, Nanchang University, Nanchang, China
| | - Lequan Wen
- Joint Program of Nanchang University and Queen Mary University of London, Nanchang, China
| | - Ruoyu Huang
- Affiliated Stomatological Hospital of Nanchang University, Nanchang, China
| | - Mengyun Sun
- Department of Physiology, Basic Medical College, Nanchang University, Nanchang, China
| | - Yun Gao
- Department of Physiology, Basic Medical College, Nanchang University, Nanchang, China.,Jiangxi Provincial Key Laboratory of Autonomic Nervous Function and Disease, Nanchang, China
| | - Wei Xiong
- Affiliated Stomatological Hospital of Nanchang University, Nanchang, China.,Jiangxi Provincial Key Laboratory of Oral Biomedicine, Nanchang, China
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