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Campbell A, Bae J, Hein M, Hillis SL, Rebeck ON, Rakel BA, Grice E, Gardner SE. The heterogeneous wound microbiome varies with wound care pain, dressing type, and inflammatory gene expression. Wound Repair Regen 2024. [PMID: 38666460 DOI: 10.1111/wrr.13184] [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: 10/20/2023] [Revised: 03/11/2024] [Accepted: 04/04/2024] [Indexed: 09/28/2024]
Abstract
Wound dressing changes are essential procedures for wound management. However, ~50% of patients experience severe pain during these procedures despite the availability of analgesic medications, indicating a need for novel therapeutics that address underlying causes of pain. Along with other clinical factors, wound pathogens and inflammatory immune responses have previously been implicated in wound pain. To test whether these factors could contribute to severe pain during wound dressing changes, we conducted an exploratory, cross-sectional analysis of patient-reported pain, inflammatory immune responses, and wound microbiome composition in 445 wounds at the time of a study dressing change. We profiled the bacterial composition of 406 wounds using 16S ribosomal RNA amplicon sequencing and quantified gene expression of 13 inflammatory markers in wound fluid using quantitative real-time polymerase chain reaction (qPCR). Neither inflammatory gene expression nor clinically observed inflammation were associated with severe pain, but Corynebacterium and Streptococcus were of lower relative abundance in wounds of patients reporting severe pain than those reporting little or no pain. Wound microbiome composition differed by wound location, and correlated with six of the inflammatory markers, including complement receptor C5AR1, pro-inflammatory cytokine interleukin (IL)1β, chemokine IL-8, matrix metalloproteinase MMP2, and the antimicrobial peptide encoding cathelicidin antimicrobial peptide. Interestingly, we found a relationship between the wound microbiome and vacuum-assisted wound closure (VAC). These findings identify preliminary, associative relationships between wound microbiota and host factors which motivate future investigation into the directional relationships between wound care pain, wound closure technologies, and the wound microbiome.
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Affiliation(s)
- Amy Campbell
- The University of Iowa College of Nursing, Iowa City, Iowa, USA
| | - Jaewon Bae
- The University of Iowa College of Nursing, Iowa City, Iowa, USA
| | - Maria Hein
- The University of Iowa College of Nursing, Iowa City, Iowa, USA
| | | | - Olivia N Rebeck
- The University of Iowa College of Nursing, Iowa City, Iowa, USA
| | - Barbara A Rakel
- The University of Iowa College of Nursing, Iowa City, Iowa, USA
| | - Elizabeth Grice
- The University of Iowa College of Nursing, Iowa City, Iowa, USA
| | - Sue E Gardner
- The University of Iowa College of Nursing, Iowa City, Iowa, USA
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Drinovac Vlah V, Bach-Rojecky L. Mirror-Image Pain Update: Complex Interactions Between Central and Peripheral Mechanisms. Mol Neurobiol 2024:10.1007/s12035-024-04102-x. [PMID: 38602655 DOI: 10.1007/s12035-024-04102-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 03/06/2024] [Indexed: 04/12/2024]
Abstract
The appearance of contralateral effects after unilateral injury has been shown in various experimental pain models, as well as in clinics. They consist of a diversity of phenomena in contralateral peripheral nerves, sensory ganglia, or spinal cord: from structural changes and altered gene or protein expression to functional consequences such as the development of mirror-image pain (MP). Although MP is a well-documented phenomenon, the exact molecular mechanism underlying the induction and maintenance of mirror-like spread of pain is still an unresolved challenge. MP has generally been explained by central sensitization mechanisms leading to facilitation of pain impulse transfer through neural connections between the two sides of the central nervous system. On the contrary, the peripheral nervous system (PNS) was usually regarded unlikely to evoke such a symmetrical phenomenon. However, recent findings provided evidence that events in the PNS could play a significant role in MP induction. This manuscript provides an updated and comprehensive synthesis of the MP phenomenon and summarizes the available data on the mechanisms. A more detailed focus is placed on reported evidence for peripheral mechanisms behind the MP phenomenon, which were not reviewed up to now.
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Affiliation(s)
- Višnja Drinovac Vlah
- Department of Pharmacology, University of Zagreb Faculty of Pharmacy and Biochemistry, Domagojeva 2, 10000, Zagreb, Croatia
| | - Lidija Bach-Rojecky
- Department of Pharmacology, University of Zagreb Faculty of Pharmacy and Biochemistry, Domagojeva 2, 10000, Zagreb, Croatia.
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Yang X, Yuan C, Wang H, Wang Y, Liu M, Li Z, Zhang J. Changes in serum angiogenic factors among patients with acute pain and subacute pain. Front Mol Neurosci 2022; 15:960460. [PMID: 35909446 PMCID: PMC9335149 DOI: 10.3389/fnmol.2022.960460] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 06/27/2022] [Indexed: 11/29/2022] Open
Abstract
Screening serum biomarkers for acute and subacute pain is important for precise pain management. This study aimed to examine serum levels of angiogenic factors in patients with acute and subacute pain as potential biomarkers. Serum samples were collected from 12 healthy controls, 20 patients with postherpetic neuralgia (PHN), 4 with low back pain (LBP), and 1 with trigeminal neuralgia (TN). Pain intensity in these patients was evaluated using the visual analog scale (VAS). The serum concentrations of 11 angiogenic biomarkers were examined by Milliplex Map Human Angiogenesis Magnetic Bead Panel 2. The pain assessment from VAS showed that all patients showed moderate and severe pain. Among 11 angiogenic factors, osteopontin (OPN), thrombospondin-2 (TSP-2), soluble platelet endothelial cell adhesion molecule-1 (sPECAM-1), soluble urokinase-type plasminogen activator receptor (suPAR), and soluble epidermal growth factor receptors (sErbB2) were up-regulated and soluble interleukin-6 receptor α (sIL-6Rα) were down-regulated in patients with pain compared to the healthy participants (all P-values were < 0.005). Moreover, a linear regression model showed that the serum OPN concentration was correlated with pain intensity in patients with PHN (P = 0.03). There was no significant difference between the serum concentration of soluble epidermal growth factor receptors, sErbB3, soluble AXL, tenascin, and soluble neuropilin-1 in patients with acute and subacute pain and that of healthy controls. The results of this study provided new valuable insights into our understanding of angiogenic factors that may contribute to as mechanistic biomarkers of pain, and reveal the pathophysiological mechanism of pain. Clinical Trial Registration:www.chictr.org.cn, identifier ChiCTR2200061775.
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Affiliation(s)
- Xuewei Yang
- Department of Anesthesiology and Pain Medical Center, Tianjin Union Medical Center, Nankai University, Tianjin, China
| | - Chunmei Yuan
- Department of Anesthesiology and Pain Medical Center, Tianjin Union Medical Center, Nankai University, Tianjin, China
| | - Huanling Wang
- Department of Anesthesiology and Pain Medical Center, Tianjin Union Medical Center, Nankai University, Tianjin, China
| | - Yunxia Wang
- Department of Anesthesiology and Pain Medical Center, Tianjin Union Medical Center, Nankai University, Tianjin, China
| | - Mei Liu
- Department of Anesthesiology and Pain Medical Center, Tianjin Union Medical Center, Nankai University, Tianjin, China
| | - Zongjin Li
- School of Medicine, Nankai University, Tianjin, China
| | - Jun Zhang
- Department of Anesthesiology and Pain Medical Center, Tianjin Union Medical Center, Nankai University, Tianjin, China
- School of Medicine, Nankai University, Tianjin, China
- *Correspondence: Jun Zhang,
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Xiang Y, Dai J, Xu L, Li X, Jiang J, Xu J. Research progress in immune microenvironment regulation of muscle atrophy induced by peripheral nerve injury. Life Sci 2021; 287:120117. [PMID: 34740577 DOI: 10.1016/j.lfs.2021.120117] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 09/18/2021] [Accepted: 10/28/2021] [Indexed: 01/08/2023]
Abstract
Denervated skeletal muscular atrophy is primarily characterized by loss of muscle strength and mass and an unideal functional recovery of the muscle after extended denervation. This review emphasizes the interaction between the immune system and the denervated skeletal muscle. Immune cells such as neutrophils, macrophages and T-cells are activated and migrate to denervated muscle, where they release a high concentration of cytokines and chemokines. The migration of these immune cells, the transformation of different functional immune cell subtypes, and the cytokine network in the immune microenvironment may be involved in the regulatory process of muscle atrophy or repair. However, the exact mechanisms of the interaction between these immune cells and immune molecules in skeletal muscles are unclear. In this paper, the immune microenvironment regulation of muscle atrophy induced by peripheral nerve injury is reviewed.
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Affiliation(s)
- Yaoxian Xiang
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, China; Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai, China; Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, China
| | - Junxi Dai
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, China; Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai, China; Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, China
| | - Lei Xu
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, China; Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai, China; Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, China
| | - Xiaokang Li
- Natl Res Inst Child Hlth & Dev, Div Transplantat Immunol, Tokyo, Japan
| | - Junjian Jiang
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, China; Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai, China; Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, China.
| | - Jianguang Xu
- Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, China; Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai, China; Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, China; School of Rehabilitation Science, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
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Manganotti P, Bellavita G, Tommasini V, D Acunto L, Fabris M, Cecotti L, Furlanis G, Sartori A, Bonzi L, Buoite Stella A, Pesavento V. Cerebrospinal fluid and serum interleukins 6 and 8 during the acute and recovery phase in COVID-19 neuropathy patients. J Med Virol 2021; 93:5432-5437. [PMID: 33951196 PMCID: PMC8242417 DOI: 10.1002/jmv.27061] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/23/2021] [Accepted: 05/03/2021] [Indexed: 01/08/2023]
Abstract
This case series describes three patients affected by severe acute respiratory syndrome coronavirus 2, who developed polyradiculoneuritis as a probable neurological complication of coronavirus disease 2019 (COVID-19). A diagnosis of Guillain Barré syndrome was made on the basis of clinical symptoms, cerebrospinal fluid analysis, and electroneurography. In all of them, the therapeutic approach included the administration of intravenous immunoglobulin (0.4 gr/kg for 5 days), which resulted in the improvement of neurological symptoms. Clinical neurophysiology revealed the presence of conduction block, absence of F waves, and in two cases, a significant decrease in amplitude of compound motor action potential cMAP. Due to the potential role of inflammation on symptoms development and prognosis, interleukin-6 (IL-6) and IL-8 levels were measured in serum and cerebrospinal fluid during the acute phase, while only serum was tested after recovery. Both IL-6 and IL-8 were found increased during the acute phase, both in the serum and cerebrospinal fluid, whereas 4 months after admission (at complete recovery), only IL-8 remained elevated in the serum. These results confirm the inflammatory response that might be linked to peripheral nervous system complications and encourage the use of IL-6 and IL-8 as prognostic biomarkers in COVID-19.
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Affiliation(s)
- Paolo Manganotti
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, Cattinara University Hospital ASUGI, University of Trieste, Trieste, Italy
| | - Giulia Bellavita
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, Cattinara University Hospital ASUGI, University of Trieste, Trieste, Italy
| | - Valentina Tommasini
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, Cattinara University Hospital ASUGI, University of Trieste, Trieste, Italy
| | - Laura D Acunto
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, Cattinara University Hospital ASUGI, University of Trieste, Trieste, Italy
| | - Martina Fabris
- Lab. Malattie Autoimmuni, SOC Istituto di Patologia Clinica, Azienda Sanitaria Universitaria Friuli Centrale, Udine, Italy
| | - Laura Cecotti
- Rehabilitation Unit of Severe cerebrovascular lesion, Gervasutta Hospital, Udine, Italy
| | - Giovanni Furlanis
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, Cattinara University Hospital ASUGI, University of Trieste, Trieste, Italy
| | - Arianna Sartori
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, Cattinara University Hospital ASUGI, University of Trieste, Trieste, Italy
| | - Lucia Bonzi
- Rehabilitation Unit, Maggiore City Hospital Department of Medicine, Surgery and Health Sciences, ASUGI, Trieste, Italy
| | - Alex Buoite Stella
- Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, Cattinara University Hospital ASUGI, University of Trieste, Trieste, Italy
| | - Valentina Pesavento
- Rehabilitation Unit, Maggiore City Hospital Department of Medicine, Surgery and Health Sciences, ASUGI, Trieste, Italy
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Liu M, Li Y, Zhong J, Xia L, Dou N. The effect of IL-6/Piezo2 on the trigeminal neuropathic pain. Aging (Albany NY) 2021; 13:13615-13625. [PMID: 33893246 PMCID: PMC8202871 DOI: 10.18632/aging.202887] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 03/04/2021] [Indexed: 01/27/2023]
Abstract
The nature of trigeminal neuropathic pain (TN) attacks is regarded as the ignition of ectopic action potentials from the trigeminal root following vascular compression, which seemed to be related to transmembrane proteins and inflammation factors. This study focused on the mechanosensitive channel Piezo2 and cytokine IL-6. The chronic constriction injury of infraorbital nerve in SD rats was used to establish the TN model. The trigeminal ganglion was then achieved to perform immunocytochemistry studies. A significant upregulation of Piezo2 and IL-6 was showed in the TN model rats. The Piezo2 positive accounted for 72.3±9.5% in those IL-6 positive neurons. The Piezo2 co-localized with CGRP, IB4 and NF-200 but not with GFAP, which implied that it was expressed in both the C-type and the A-type neurons. After administration of GsMTx4 or anti-rat IL-6 antibody in the TN model, the dynamic allodynia and pinprick hyperalgesia scores as well as the mechanical threshold changed significantly. In the sham-operation rates, with local administration of IL-6, an upregulation of Piezo2 was also exhibited. Our study demonstrated that the up-regulation of Piezo2 in the pain afferent neurons following trigeminal nerve injury may play a role in the development of the neuralgia. Meanwhile, the expression of Piezo2 may be modulated by inflammatory cytokines, such as IL-6.
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Affiliation(s)
- MingXing Liu
- Department of Neurosurgery, Qingdao Municipal Hospital, Qingdao 266000, China
| | - Yan Li
- Department of Neurosurgery, Qingdao Municipal Hospital, Qingdao 266000, China
| | - Jun Zhong
- Department of Neurosurgery, XinHua Hospital, The Cranial Nerve Disease Center of Shanghai, Shanghai JiaoTong University School of Medicine, Shanghai 200092, China
| | - Lei Xia
- Department of Neurosurgery, XinHua Hospital, The Cranial Nerve Disease Center of Shanghai, Shanghai JiaoTong University School of Medicine, Shanghai 200092, China
| | - NingNing Dou
- Department of Neurosurgery, XinHua Hospital, The Cranial Nerve Disease Center of Shanghai, Shanghai JiaoTong University School of Medicine, Shanghai 200092, China
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Sebba A. Pain: A Review of Interleukin-6 and Its Roles in the Pain of Rheumatoid Arthritis. Open Access Rheumatol 2021; 13:31-43. [PMID: 33707975 PMCID: PMC7943546 DOI: 10.2147/oarrr.s291388] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 01/22/2021] [Indexed: 12/29/2022] Open
Abstract
Pain is a major and common symptom reported as a top priority in patients with rheumatoid arthritis (RA). Intuitively, RA-related pain is often considered to be a natural consequence of peripheral inflammation, so treatment of RA is expected to manage pain concurrently as part of inflammation control. However, pain in patients with RA can be poorly correlated with objective measures of inflammation, for example, in patients who are otherwise in remission. Joint damage appears to account for only a fraction of this residual pain. Emerging evidence suggests that alteration of peripheral and central pain processing contributes to RA-related pain; this is parallel to, but somewhat independent of, joint inflammation. Interleukin (IL)-6 is a proinflammatory cytokine that contributes to the pathogenesis of RA. It exerts systemic effects via signaling through soluble forms of the IL-6 receptor (“trans-signaling”). Evidence from preclinical studies demonstrates that intra-articular IL-6 can produce long-lasting peripheral sensitization to mechanical stimulation and suggests an important role for IL-6 in central pain sensitization. This may be partly explained by its ability to activate neurons through trans-signaling, affecting nociceptive plasticity and nerve fiber regrowth. Local activity at neuron endings may culminate in altered pain processing in the central nervous system because of persistent signaling from sensitized peripheral neurons. Peripheral and central sensitization can promote the development of chronic pain, which can have a significant impact on patients’ health and quality of life. A proportion of pain in RA may be more appropriately managed as an entity separate from inflammation. Both the peripheral and central nervous systems should be recognized as important potential systems targeted by RA. The substantial burden of RA-related chronic pain suggests that pain should be a key focus in RA management and should be assessed and addressed early and separately from the inflammatory component.
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Affiliation(s)
- Anthony Sebba
- Division of Rheumatology, University of South Florida, Tampa, FL, USA
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Wang C, Chen P, Lin D, Chen Y, Wu Z, Lin X. [Effects of different materials for partial sciatic nerve ligation on glial cell activation in rat models of chronic constriction injury]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2020; 40:1207-1212. [PMID: 32895191 DOI: 10.12122/j.issn.1673-4254.2020.08.20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To compare the effects of different materials for partial sciatic nerve ligation on glial cell activation in the spinal cord in a rat model of chronic constriction injury (CCI). METHODS SD rats were randomly divided into the sham group (n=15), silk suture CCI group (n=15) and chromic catgut CCI group (n=14). The mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) of the rats were detected at 3, 7, 11 and 15 days after the operation. The changes in the sciatic nerve, the activation of spinal cord glial cells and the expression of inflammatory factors were observed using Western blotting and RT-PCR. RESULTS At 3 to 15 days after the surgery, MWT and TWL of the rats were significantly lower in silk suture group and chromic catgut group than in the control group (P < 0.05), and was significantly lower in chromic catgut group than in the silk suture group (P < 0.05) at 3 days after the surgery. The results of sciatic nerve myelin staining showed that the sciatic nerve was damaged and demyelinated in both the ligation groups. The expressions of CD11b, GFAP, IL-1β and TNF-α in the two ligation groups were similar and all significantly higher than those in the control group (P < 0.05). IL-6 mRNA level was significantly higher in chromic catgut group than in the silk suture group (P < 0.05). CONCLUSIONS The CCI models established by partial sciatic nerve ligation with silk suture and chromic catgut all show glial activation, and the inflammatory response is stronger in chromic catgut group.
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Affiliation(s)
- Chen Wang
- First Clinical Medical School, Guangzhou University of Chinese Medicine, Guangzhou 510006, China
| | - Peng Chen
- Basic Medical School, Guizhou University of Traditional Chinese Medicine, Guiyang 550025, China
| | - Dongsheng Lin
- First Clinical Medical School, Guangzhou University of Chinese Medicine, Guangzhou 510006, China
| | - Yi Chen
- First Clinical Medical School, Guangzhou University of Chinese Medicine, Guangzhou 510006, China
| | - Zhibing Wu
- Department of Neurology, First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Xingdong Lin
- Department of Neurology, Third Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510240, China
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Yang QQ, Li HN, Zhang ST, Yu YL, Wei W, Zhang X, Wang JY, Zeng XY. Red nucleus IL-6 mediates the maintenance of neuropathic pain by inducing the productions of TNF-α and IL-1β through the JAK2/STAT3 and ERK signaling pathways. Neuropathology 2020; 40:347-357. [PMID: 32380573 DOI: 10.1111/neup.12653] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 02/14/2020] [Accepted: 02/21/2020] [Indexed: 01/13/2023]
Abstract
We previously reported that interleukin (IL)-6 in the red nucleus (RN) is involved in the maintenance of neuropathic pain induced by spared nerve injury (SNI), and exerts a facilitatory effect via Janus-activated kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) and extracellular signal-regulated kinase (ERK) signal transduction pathways. The present study aimed at investigating the roles of tumor necrosis factor-α (TNF-α) and IL-1β in RN IL-6-mediated maintenance of neuropathic pain and related signal transduction pathways. Being similar to the elevation of RN IL-6 three weeks after SNI, increased protein levels of both TNF-α and IL-1β were also observed in the contralateral RN three weeks after the nerve injury. The upregulations of TNF-α and IL-1β were closely correlative with IL-6 and suppressed by intrarubral injection of a neutralizing antibody against IL-6. Administration of either the JAK2 antagonist AG490 or the ERK antagonist PD98059 to the RN of rats with SNI remarkably increased the paw withdrawal threshold (PWT) and inhibited the up-regulations of local TNF-α and IL-1β. Further experiments indicated that intrarubral injection of exogenous IL-6 in naive rats apparently lowered the PWT of the contralateral hindpaw and boosted the local expressions of TNF-α and IL-1β. Pretreatment with AG490 could block IL-6-induced tactile hypersensitivity and suppress the up-regulations of both TNF-α and IL-1β. However, injection of PD98059 in advance only inhibited the upregulation of IL-1β, but not TNF-α. These findings indicate that RN IL-6 mediates the maintenance of neuropathic pain by inducing the productions of TNF-α and IL-1β. IL-6 induces the expression of TNF-α through the JAK2/STAT3 pathway, and the production of IL-1β through the JAK2/STAT3 and ERK pathways.
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Affiliation(s)
- Qing-Qing Yang
- Department of Laboratory Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.,Department of Pathogenic Biology and Immunology, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Hao-Nan Li
- Department of Pathogenic Biology and Immunology, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Shu-Ting Zhang
- Department of Pathogenic Biology and Immunology, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Yan-Li Yu
- Department of Pathogenic Biology and Immunology, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Wei Wei
- Department of Pathogenic Biology and Immunology, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Xi Zhang
- Department of Pathogenic Biology and Immunology, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Jun-Yang Wang
- Department of Pathogenic Biology and Immunology, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Xiao-Yan Zeng
- Department of Laboratory Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
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Liu MX, Zhong J, Xia L, Dou NN, Li ST. IL-6 contributes to Na v1.3 up-regulation in trigeminal nerve following chronic constriction injury. Neurol Res 2020; 42:504-514. [PMID: 32279611 DOI: 10.1080/01616412.2020.1747719] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Background: To verify the hypothesis that the nature of trigeminal neuralgia (TN) is an ectopic impulse induced by sodium channel modulated by cytokines, we conducted an animal study using the infraorbital nerve chronic constriction injury (CCI) model in rats.Method: The expression of Nav1.3 or IL-6 in the infraorbital nerve (ION) and trigeminal ganglion (TG) were detected by western blot and immunocytochemistry after administration of antisense oligodeoxynucleotide sequence (AS), IL-6 or Anti-IL-6.Results: With intrathecal administration of AS or mismatch oligodeoxynucleotide sequence (MM) in the CCI rats, the Nav1.3-IR in ION and TG accounted for 2.2 ± 0.51% and 8.5 ± 3.1% in AS+CCI group vs. 6.9 ± 1.3% and 38.7 ± 4.8% in MM+CCI group (p < 0.05), respectively. While with local administration of IL-6 in those with sham operation, it accounted for 7.4 ± 2.1% and 45.5 ± 3.4% in IL-6+ sham group vs. 1.9 ± 0.67% and 8.1 ± 1.3% in vehicle+sham group (p < 0.05); with local administration of anti-IL-6 in CCI rats, 4.5 ± 0.78% and 32.1 ± 9.6% in Anti-IL-6+ CCI group vs 8.9 ± 2.1% and 61.4 ± 11.2% in vehicle+CCI group (p < 0.05).Discussion: We believe that the emergence of Nav1.3 from the compressed trigeminal nerve might be an important structural basis for the development of the ectopic excitability on the axon and IL-6 may play a role of necessary precondition.
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Affiliation(s)
- Ming-Xing Liu
- Department of Neurosurgery, Qingdao Municipal Hospital, Qingdao, China
| | - Jun Zhong
- Department of Neurosurgery, XinHua Hospital (The Cranial Nerve Disease Center of Shanghai), Shanghai JiaoTong University School of Medicine, Shanghai, China
| | - Lei Xia
- Department of Neurosurgery, XinHua Hospital (The Cranial Nerve Disease Center of Shanghai), Shanghai JiaoTong University School of Medicine, Shanghai, China
| | - Ning-Ning Dou
- Department of Neurosurgery, XinHua Hospital (The Cranial Nerve Disease Center of Shanghai), Shanghai JiaoTong University School of Medicine, Shanghai, China
| | - Shi-Ting Li
- Department of Neurosurgery, XinHua Hospital (The Cranial Nerve Disease Center of Shanghai), Shanghai JiaoTong University School of Medicine, Shanghai, China
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Dubový P, Hradilová-Svíženská I, Klusáková I, Brázda V, Joukal M. Interleukin-6 contributes to initiation of neuronal regeneration program in the remote dorsal root ganglia neurons after sciatic nerve injury. Histochem Cell Biol 2019; 152:109-117. [PMID: 30927067 DOI: 10.1007/s00418-019-01779-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/19/2019] [Indexed: 01/18/2023]
Abstract
To assess the potential role of IL-6 in sciatic nerve injury-induced activation of a pro-regenerative state in remote dorsal root ganglia (DRG) neurons, we compared protein levels of SCG-10 and activated STAT3, as well as axon regeneration in IL-6 knockout (IL-6ko) mice and their wild-type (WT) counterparts. Unilateral sciatic nerve compression and transection upregulated SCG-10 protein levels and activated STAT3 in DRG neurons not only in lumbar but also in cervical segments of WT mice. A pro-regenerative state induced by prior sciatic nerve lesion in cervical DRG neurons of WT mice was also shown by testing for axon regeneration in crushed ulnar nerve. DRG neurons from IL-6ko mice also displayed bilaterally increased levels of SCG-10 and STAT3 in both lumbar and cervical segments after sciatic nerve lesions. However, levels of SCG-10 protein in lumbar and cervical DRG of IL-6ko mice were significantly lower than those of their WT counterparts. Sciatic nerve injury induced a lower level of SCG-10 in cervical DRG of IL-6ko than WT mice, and this correlates with significantly shorter regeneration of axons distal to the crushed ulnar nerve. These results suggest that IL-6 contributes, at the very least, to initiation of the neuronal regeneration program in remote DRG neurons after unilateral sciatic nerve injury.
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Affiliation(s)
- Petr Dubový
- Department of Anatomy, Cellular and Molecular Research Group, Faculty of Medicine, Masaryk University, Kamenice 3, 62500, Brno, Czech Republic
| | - Ivana Hradilová-Svíženská
- Department of Anatomy, Cellular and Molecular Research Group, Faculty of Medicine, Masaryk University, Kamenice 3, 62500, Brno, Czech Republic
| | - Ilona Klusáková
- Department of Anatomy, Cellular and Molecular Research Group, Faculty of Medicine, Masaryk University, Kamenice 3, 62500, Brno, Czech Republic
| | - Václav Brázda
- Department of Anatomy, Cellular and Molecular Research Group, Faculty of Medicine, Masaryk University, Kamenice 3, 62500, Brno, Czech Republic
| | - Marek Joukal
- Department of Anatomy, Cellular and Molecular Research Group, Faculty of Medicine, Masaryk University, Kamenice 3, 62500, Brno, Czech Republic.
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Dubový P, Klusáková I, Hradilová-Svíženská I, Brázda V, Kohoutková M, Joukal M. A Conditioning Sciatic Nerve Lesion Triggers a Pro-regenerative State in Primary Sensory Neurons Also of Dorsal Root Ganglia Non-associated With the Damaged Nerve. Front Cell Neurosci 2019; 13:11. [PMID: 30778286 PMCID: PMC6369159 DOI: 10.3389/fncel.2019.00011] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 01/14/2019] [Indexed: 12/19/2022] Open
Abstract
The primary sensory neurons of dorsal root ganglia (DRG) are a very useful model to study the neuronal regenerative program that is a prerequisite for successful axon regeneration after peripheral nerve injury. Seven days after a unilateral sciatic nerve injury by compression or transection, we detected a bilateral increase in growth-associated protein-43 (GAP-43) and superior cervical ganglion-10 (SCG-10) mRNA and protein levels not only in DRG neurons of lumbar spinal cord segments (L4-L5) associated with injured nerve, but also in remote cervical segments (C6-C8). The increase in regeneration-associated proteins in the cervical DRG neurons was associated with the greater length of regenerated axons 1 day after ulnar nerve crush following prior sciatic nerve injury as compared to controls with only ulnar nerve crush. The increased axonal regeneration capacity of cervical DRG neurons after a prior conditioning sciatic nerve lesion was confirmed by neurite outgrowth assay of in vitro cultivated DRG neurons. Intrathecal injection of IL-6 or a JAK2 inhibitor (AG490) revealed a role for the IL-6 signaling pathway in activating the pro-regenerative state in remote DRG neurons. Our results suggest that the pro-regenerative state induced in the DRG neurons non-associated with the injured nerve reflects a systemic reaction of these neurons to unilateral sciatic nerve injury.
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Affiliation(s)
- Petr Dubový
- Department of Anatomy, Laboratory of Cellular and Molecular Neurobiology, Faculty of Medicine, Masaryk University, Brno, Czechia
| | - Ilona Klusáková
- Department of Anatomy, Laboratory of Cellular and Molecular Neurobiology, Faculty of Medicine, Masaryk University, Brno, Czechia
| | - Ivana Hradilová-Svíženská
- Department of Anatomy, Laboratory of Cellular and Molecular Neurobiology, Faculty of Medicine, Masaryk University, Brno, Czechia
| | - Václav Brázda
- Department of Anatomy, Laboratory of Cellular and Molecular Neurobiology, Faculty of Medicine, Masaryk University, Brno, Czechia
| | - Marcela Kohoutková
- Department of Anatomy, Laboratory of Cellular and Molecular Neurobiology, Faculty of Medicine, Masaryk University, Brno, Czechia
| | - Marek Joukal
- Department of Anatomy, Laboratory of Cellular and Molecular Neurobiology, Faculty of Medicine, Masaryk University, Brno, Czechia
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Liu MX, Zhong J, Xia L, Dou NN, Li ST. A correlative analysis between inflammatory cytokines and trigeminal neuralgia or hemifacial spasm. Neurol Res 2019; 41:335-340. [PMID: 30612530 DOI: 10.1080/01616412.2018.1564188] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND It is necessary to understand the mechanism of trigeminal neuralgia (TN) and hemifacial spasm (HFS) in order to seek for an effective noninvasive remedy. As previous studies implied that inflammatory cytokines induced by demyelination following the nerve injury may be the initiated factor causing neuropathic pain, we attempt to analyze the correlation between cytokines and these hyperactive cranial nerve disorders. METHOD The consecutive patients whose diagnosis were confirmed by microvascular decompression surgery as primary TN or HFS caused by vascular compression and healthy volunteers between March and May 2018 in XinHua Hospital Shanghai JiaoTong University School of Medicine were recruited. Preoperatively, venous blood was collected and the protein concentrations of IL-1β, IL-2, IL-6, IL-8, IL-10, TNF-α and IFN-γ were determined with ELISA. Each cytokine was compared between the patients and healthy volunteers. RESULTS Ultimately, 28 healthy volunteers as well as 44 TN and 47 HFS patients were enrolled in this investigation. The serum levels of IL-1β, IL-6, IL-8 and TNF-α in either HFS or TN patients were significantly higher than that in healthy volunteers (p < 0.05), yet which were similar between TN and HFS patients (p > 0.05). Besides, there was a significantly correlation between IL-6 concentration and severity of HFS (r = 0.933, p < 0.05) or TN (r = 0.943, p < 0.05). DISCUSSION Vascular compression of trigeminal or facial nerve roots may induce a rise in variety of cytokines, and IL-6 may play an important role in the signaling pathways to generate ectopic impulses from these cranial nerves.
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Affiliation(s)
- Ming-Xing Liu
- a Department of Neurosurgery , XinHua Hospital (The Cranial Nerve Disease Center of Shanghai), Shanghai JiaoTong University School of Medicine , Shanghai , China
| | - Jun Zhong
- a Department of Neurosurgery , XinHua Hospital (The Cranial Nerve Disease Center of Shanghai), Shanghai JiaoTong University School of Medicine , Shanghai , China
| | - Lei Xia
- a Department of Neurosurgery , XinHua Hospital (The Cranial Nerve Disease Center of Shanghai), Shanghai JiaoTong University School of Medicine , Shanghai , China
| | - Ning-Ning Dou
- a Department of Neurosurgery , XinHua Hospital (The Cranial Nerve Disease Center of Shanghai), Shanghai JiaoTong University School of Medicine , Shanghai , China
| | - Shi-Ting Li
- a Department of Neurosurgery , XinHua Hospital (The Cranial Nerve Disease Center of Shanghai), Shanghai JiaoTong University School of Medicine , Shanghai , China
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14
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Jurga AM, Rojewska E, Makuch W, Mika J. Lipopolysaccharide from Rhodobacter sphaeroides (TLR4 antagonist) attenuates hypersensitivity and modulates nociceptive factors. PHARMACEUTICAL BIOLOGY 2018; 56:275-286. [PMID: 29656686 PMCID: PMC6130482 DOI: 10.1080/13880209.2018.1457061] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
CONTEXT Accumulating evidence has demonstrated that Toll-like receptors (TLRs), especially TLR4 localized on microglia/macrophages, may play a significant role in nociception. OBJECTIVE We examine the role of TLR4 in a neuropathic pain model. Using behavioural/biochemical methods, we examined the influence of TLR4 antagonist on levels of hypersensitivity and nociceptive factors whose contribution to neuropathy development has been confirmed. MATERIALS AND METHODS Behavioural (von Frey's/cold plate) tests were performed with Wistar male rats after intrathecal administration of a TLR4 antagonist (LPS-RS ULTRAPURE (LPS-RSU), 20 μG: lipopolysaccharide from Rhodobacter sphaeroides, InvivoGen, San Diego, CA) 16 H and 1 h before chronic constriction injury (cci) to the sciatic nerve and then daily for 7 d. three groups were used: an intact group and two cci-exposed groups that received vehicle or LPS-RSU. tissue [spinal cord/dorsal root ganglia (DRG)] for western blot analysis was collected on day 7. RESULTS The pharmacological blockade of TLR4 diminished mechanical (from ca. 40% to 16% that in the INTACT group) and thermal (from ca. 51% to 32% that in the INTACT group) hypersensitivity despite the enhanced activation of IBA-1-positive cells in DRG. Moreover, LPS-RSU changed the ratio between IL-18/IL-18BP and MMP-9/TIMP-1 in favour of the increase of antinociceptive factors IL-18BP (25%-spinal; 96%-DRG) and TIMP-1 (15%-spinal; 50%-DRG) and additionally led to an increased IL-6 (40%-spinal; 161%-DRG), which is known to have analgesic properties in neuropathy. CONCLUSIONS Our results provide evidence that LPS-RSU influences pain through the expression of TLR4. TLR4 blockade has analgesic properties and restores the balance between nociceptive factors, which indicates its engagement in neuropathy development.
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Affiliation(s)
- Agnieszka M. Jurga
- Department of Pain Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Ewelina Rojewska
- Department of Pain Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Wioletta Makuch
- Department of Pain Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Joanna Mika
- Department of Pain Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
- CONTACT Joanna MikaDepartment of Pain Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna Str., 31343Krakow, Poland
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Raoof R, Willemen HLDM, Eijkelkamp N. Divergent roles of immune cells and their mediators in pain. Rheumatology (Oxford) 2018; 57:429-440. [PMID: 28968842 PMCID: PMC5850827 DOI: 10.1093/rheumatology/kex308] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Indexed: 12/20/2022] Open
Abstract
Chronic pain is a major debilitating condition that is difficult to treat. Although chronic pain may appear to be a disorder of the nervous system, crucial roles for immune cells and their mediators have been identified as important contributors in various types of pain. This review focuses on how the immune system regulates pain and discusses the emerging roles of immune cells in the initiation or maintenance of chronic pain. We highlight which immune cells infiltrate damaged nerves, the dorsal root ganglia, spinal cord and tissues around free nerve endings and discuss through which mechanisms they control pain. Finally we discuss emerging roles of the immune system in resolving pain and how the immune system contributes to the transition from acute to chronic pain. We propose that targeting some of these immune processes may provide novel therapeutic opportunities for the treatment of chronic pain.
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Affiliation(s)
- Ramin Raoof
- Laboratory of Translational Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Hanneke L D M Willemen
- Laboratory of Neuroimmunology and Developmental Origins of Disease (NIDOD), University Medical Center Utrecht, Utrecht, The Netherlands
| | - Niels Eijkelkamp
- Laboratory of Translational Immunology, University Medical Center Utrecht, Utrecht, The Netherlands.,Laboratory of Neuroimmunology and Developmental Origins of Disease (NIDOD), University Medical Center Utrecht, Utrecht, The Netherlands
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16
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Bilateral activation of STAT3 by phosphorylation at the tyrosine-705 (Y705) and serine-727 (S727) positions and its nuclear translocation in primary sensory neurons following unilateral sciatic nerve injury. Histochem Cell Biol 2018; 150:37-47. [PMID: 29488000 DOI: 10.1007/s00418-018-1656-y] [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] [Accepted: 02/24/2018] [Indexed: 01/06/2023]
Abstract
Unilateral sciatic nerve compression (SNC) or complete sciatic nerve transection (CSNT), both varying degrees of nerve injury, induced activation of STAT3 bilaterally in the dorsal root ganglia (DRG) neurons of lumbar (L4-L5) as well as cervical (C6-C8) spinal cord segments. STAT3 activation was by phosphorylation at the tyrosine-705 (Y705) and serine-727 (S727) positions and was followed by their nuclear translocation. This is the first evidence of STAT3(S727) activation together with the well-known activation of STAT3(Y705) in primary sensory neurons upon peripheral nerve injury. Bilateral activation of STAT3 in DRG neurons of spinal segments anatomically both associated as well as non-associated with the injured nerve indicates diffusion of STAT3 activation inducers along the spinal cord. Increased levels of IL-6 protein in the CSF following nerve injury as well as activation and nuclear translocation of STAT3 in DRG after intrathecal injection of IL-6 shows that this cytokine, released into the subarachnoid space can penetrate the DRG to activate STAT3. Previous results on increased bilateral IL-6 synthesis and the present manifestation of STAT3 activation in remote DRG following unilateral sciatic nerve injury may reflect a systemic reaction of the DRG neurons to nerve injury.
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17
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Ding CP, Guo YJ, Li HN, Wang JY, Zeng XY. Red nucleus interleukin-6 participates in the maintenance of neuropathic pain through JAK/STAT3 and ERK signaling pathways. Exp Neurol 2017; 300:212-221. [PMID: 29183675 DOI: 10.1016/j.expneurol.2017.11.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/21/2017] [Accepted: 11/24/2017] [Indexed: 12/18/2022]
Abstract
We previously reported that interleukin-6 (IL-6) in the red nucleus (RN) is up-regulated at 3weeks after spared nerve injury (SNI), and plays facilitated role in the later maintenance of neuropathic pain. The current study aimed to reveal the roles of different signaling pathways, including Janus kinase/signal transducer and activator of transcription 3 (JAK/STAT3), extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (MAPK) and phosphatidylinositide 3-kinase/protein kinase B (PI3K/AKT), in RN IL-6-mediated pain modulation. In accord with the increase of IL-6 in the RN following SNI, the protein levels of phospho-STAT3 (p-STAT3), p-ERK and p-JNK were also up-regulated in the RN contralateral to the nerve injury side at 3weeks after SNI. The increases of p-STAT3 and p-ERK (but not p-JNK) were associated with IL-6 and could be blocked by anti-IL-6 antibody. Microinjection of JAK2 inhibitor AG490, ERK inhibitor PD98059 and also JNK inhibitor SP600125 into the RN significantly increased the paw withdrawal threshold (PWT) and alleviated SNI-induced mechanical allodynia. Further studies showed that microinjection of recombinant rat IL-6 (rrIL-6, 20ng) into the RN of normal rats significantly decreased the PWT of rats and increased the local protein levels of p-STAT3 and p-ERK, but not p-JNK. Pre-treatment with AG490 and PD98059 could prevent IL-6-induced mechanical allodynia. Whereas, p-p38 MAPK and p-AKT did not show any expression changes in the RN of rats with SNI or rats treated with rrIL-6. These results suggest that RN IL-6 participates in the later maintenance of SNI-induced neuropathic pain and plays facilitated role through activating JAK/STAT3 and ERK signaling pathways.
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Affiliation(s)
- Cui-Ping Ding
- Department of Laboratory Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China; Department of Pathogenic Biology and Immunology, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi 710061, China
| | - Yi-Jie Guo
- Department of Pathogenic Biology and Immunology, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi 710061, China
| | - Hao-Nan Li
- Department of Pathogenic Biology and Immunology, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi 710061, China
| | - Jun-Yang Wang
- Department of Pathogenic Biology and Immunology, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi 710061, China
| | - Xiao-Yan Zeng
- Department of Laboratory Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China.
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Hung AL, Lim M, Doshi TL. Targeting cytokines for treatment of neuropathic pain. Scand J Pain 2017; 17:287-293. [PMID: 29229214 DOI: 10.1016/j.sjpain.2017.08.002] [Citation(s) in RCA: 118] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 07/26/2017] [Accepted: 08/01/2017] [Indexed: 12/11/2022]
Abstract
BACKGROUND Neuropathic pain is a challenging condition often refractory to existing therapies. An increasing number of studies have indicated that the immune system plays a crucial role in the mediation of neuropathic pain. Exploration of the various functions of individual cytokines in neuropathic pain will provide greater insight into the mechanisms of neuropathic pain and suggest potential opportunities to expand the repertoire of treatment options. METHODS A literature review was performed to assess the role of pro-inflammatory and anti-inflammatory cytokines in the development of neuropathic pain. Both direct and indirect therapeutic approaches that target various cytokines for pain were reviewed. The current understanding based on preclinical and clinical studies is summarized. RESULTS AND CONCLUSIONS In both human and animal studies, neuropathic pain has been associated with a pro-inflammatory state. Analgesic therapies involving direct manipulation of various cytokines and indirect methods to alter the balance of the immune system have been explored, although there have been few large-scale clinical trials evaluating the efficacy of immune modulators in the treatment of neuropathic pain. TNF-α is perhaps the widely studied pro-inflammatory cytokine in the context of neuropathic pain, but other pro-inflammatory (IL-1β, IL-6, and IL-17) and anti-inflammatory (IL-4, IL-10, TGF-β) signaling molecules are garnering increased interest. With better appreciation and understanding of the interaction between the immune system and neuropathic pain, novel therapies may be developed to target this condition.
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Affiliation(s)
- Alice L Hung
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Michael Lim
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Tina L Doshi
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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Ding CP, Xue YS, Yu J, Guo YJ, Zeng XY, Wang JY. The Red Nucleus Interleukin-6 Participates in the Maintenance of Neuropathic Pain Induced by Spared Nerve Injury. Neurochem Res 2016; 41:3042-3051. [DOI: 10.1007/s11064-016-2023-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 07/24/2016] [Accepted: 07/28/2016] [Indexed: 11/30/2022]
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20
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Ko JS, Eddinger KA, Angert M, Chernov AV, Dolkas J, Strongin AY, Yaksh TL, Shubayev VI. Spinal activity of interleukin 6 mediates myelin basic protein-induced allodynia. Brain Behav Immun 2016; 56:378-89. [PMID: 26970355 PMCID: PMC4917441 DOI: 10.1016/j.bbi.2016.03.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 03/04/2016] [Accepted: 03/08/2016] [Indexed: 12/19/2022] Open
Abstract
Mechanosensory fibers are enveloped by myelin, a unique multilamellar membrane permitting saltatory neuronal conduction. Damage to myelin is thought to contribute to severe pain evoked by innocuous tactile stimulation (i.e., mechanical allodynia). Our earlier (Liu et al., 2012) and present data demonstrate that a single injection of a myelin basic protein-derived peptide (MBP84-104) into an intact sciatic nerve produces a robust and long-lasting (>30days) mechanical allodynia in female rats. The MBP84-104 peptide represents the immunodominant epitope and requires T cells to maintain allodynia. Surprisingly, only systemic gabapentin (a ligand of voltage-gated calcium channel α2δ1), but not ketorolac (COX inhibitor), lidocaine (sodium channel blocker) or MK801 (NMDA antagonist) reverse allodynia induced by the intrasciatic MBP84-104. The genome-wide transcriptional profiling of the sciatic nerve followed by the bioinformatics analyses of the expression changes identified interleukin (IL)-6 as the major cytokine induced by MBP84-104 in both the control and athymic T cell-deficient nude rats. The intrasciatic MBP84-104 injection resulted in both unilateral allodynia and unilateral IL-6 increase the segmental spinal cord (neurons and astrocytes). An intrathecal delivery of a function-blocking IL-6 antibody reduced the allodynia in part by the transcriptional effects in large-diameter primary afferents in DRG. Our data suggest that MBP regulates IL-6 expression in the nervous system and that the spinal IL-6 activity mediates nociceptive processing stimulated by the MBP epitopes released after damage or disease of the somatosensory nervous system.
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Affiliation(s)
- Justin S. Ko
- Department of Anesthesiology, University of California, San Diego, La Jolla, California, USA,Sungkyunkwan University School of Medicine, Samsung Medical Center, Seoul, South Korea
| | - Kelly A. Eddinger
- Department of Anesthesiology, University of California, San Diego, La Jolla, California, USA
| | - Mila Angert
- Department of Anesthesiology, University of California, San Diego, La Jolla, California, USA,VA San Diego Healthcare System, La Jolla, California, USA
| | - Andrei V. Chernov
- Sanford-Burnham Prebys Medical Discovery Institute, La Jolla, California, USA
| | - Jennifer Dolkas
- Department of Anesthesiology, University of California, San Diego, La Jolla, California, USA,VA San Diego Healthcare System, La Jolla, California, USA
| | - Alex Y. Strongin
- Sanford-Burnham Prebys Medical Discovery Institute, La Jolla, California, USA
| | - Tony L. Yaksh
- Department of Anesthesiology, University of California, San Diego, La Jolla, California, USA
| | - Veronica I. Shubayev
- Department of Anesthesiology, University of California, San Diego, La Jolla, California, USA,VA San Diego Healthcare System, La Jolla, California, USA,Corresponding Author: Veronica I. Shubayev, Department of Anesthesiology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0629. Phone: (858) 534-5278; Fax: (858) 534-1445;
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Zhou YQ, Liu Z, Liu ZH, Chen SP, Li M, Shahveranov A, Ye DW, Tian YK. Interleukin-6: an emerging regulator of pathological pain. J Neuroinflammation 2016; 13:141. [PMID: 27267059 PMCID: PMC4897919 DOI: 10.1186/s12974-016-0607-6] [Citation(s) in RCA: 255] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 06/01/2016] [Indexed: 02/08/2023] Open
Abstract
Interleukin-6 is an inflammatory cytokine with wide-ranging biological effects. It has been widely demonstrated that neuroinflammation plays a critical role in the development of pathological pain. Recently, various pathological pain models have shown elevated expression levels of interleukin-6 and its receptor in the spinal cord and dorsal root ganglia. Additionally, the administration of interleukin-6 could cause mechanical allodynia and thermal hyperalgesia, and an intrathecal injection of anti-interleukin-6 neutralizing antibody alleviated these pain-related behaviors. These studies indicated a pivotal role of interleukin-6 in pathological pain. In this review, we summarize the recent progress in understanding the roles and mechanisms of interleukin-6 in mediating pathological pain associated with bone cancer, peripheral nerve injury, spinal cord injury, chemotherapy-induced peripheral neuropathy, complete Freund’s adjuvant injection, and carrageenan injection. Understanding and regulating interleukin-6 could be an interesting lead to novel therapeutic strategies for pathological pain.
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Affiliation(s)
- Ya-Qun Zhou
- Department of Anesthesiology and Pain Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zheng Liu
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhi-Heng Liu
- Department of Anesthesiology, Shenzhen Second People's Hospital, Shenzhen, China
| | - Shu-Ping Chen
- Department of Anesthesiology and Pain Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Man Li
- Department of Neurobiology and Key Laboratory of Neurological Diseases of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Allahverdi Shahveranov
- Cancer Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Da-Wei Ye
- Cancer Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Yu-Ke Tian
- Department of Anesthesiology and Pain Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Hernangómez M, Klusáková I, Joukal M, Hradilová-Svíženská I, Guaza C, Dubový P. CD200R1 agonist attenuates glial activation, inflammatory reactions, and hypersensitivity immediately after its intrathecal application in a rat neuropathic pain model. J Neuroinflammation 2016; 13:43. [PMID: 26891688 PMCID: PMC4759712 DOI: 10.1186/s12974-016-0508-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 02/10/2016] [Indexed: 12/15/2022] Open
Abstract
Background Interaction of CD200 with its receptor CD200R has an immunoregulatory role and attenuates various types of neuroinflammatory diseases. Methods Immunofluorescence staining, western blot analysis, and RT-PCR were used to investigate the modulatory effects of CD200 fusion protein (CD200Fc) on activation of microglia and astrocytes as well as synthesis of pro- (TNF, IL-1β, IL-6) and anti-inflammatory (IL-4, IL-10) cytokines in the L4–L5 spinal cord segments in relation to behavioral signs of neuropathic pain after unilateral sterile chronic constriction injury (sCCI) of the sciatic nerve. Withdrawal thresholds for mechanical hypersensitivity and latencies for thermal hypersensitivity were measured in hind paws 1 day before operation; 1, 3, and 7 days after sCCI operation; and then 5 and 24 h after intrathecal application of artificial cerebrospinal fluid or CD200Fc. Results Seven days from sCCI operation and 5 h from intrathecal application, CD200Fc reduced mechanical and thermal hypersensitivity when compared with control animals. Simultaneously, CD200Fc attenuated activation of glial cells and decreased proinflammatory and increased anti-inflammatory cytokine messenger RNA (mRNA) levels. Administration of CD200Fc also diminished elevation of CD200 and CD200R proteins as a concomitant reaction of the modulatory system to increased neuroinflammatory reactions after nerve injury. The anti-inflammatory effect of CD200Fc dropped at 24 h after intrathecal application. Conclusions Intrathecal administration of the CD200R1 agonist CD200Fc induces very rapid suppression of neuroinflammatory reactions associated with glial activation and neuropathic pain development. This may constitute a promising and novel therapeutic approach for the treatment of neuropathic pain.
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Affiliation(s)
- Miriam Hernangómez
- Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 3, 62500, Brno, Czech Republic.
| | - Ilona Klusáková
- Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 3, 62500, Brno, Czech Republic. .,Department of Anatomy, Division of Neuroanatomy, Faculty of Medicine, Masaryk University, Kamenice 3, 62500, Brno, Czech Republic.
| | - Marek Joukal
- Department of Anatomy, Division of Neuroanatomy, Faculty of Medicine, Masaryk University, Kamenice 3, 62500, Brno, Czech Republic.
| | - Ivana Hradilová-Svíženská
- Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 3, 62500, Brno, Czech Republic. .,Department of Anatomy, Division of Neuroanatomy, Faculty of Medicine, Masaryk University, Kamenice 3, 62500, Brno, Czech Republic.
| | - Carmen Guaza
- Department of Functional and Systems Neurobiology, Neuroimmunology Group, Cajal Institute, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain.
| | - Petr Dubový
- Central European Institute of Technology (CEITEC), Masaryk University, Kamenice 3, 62500, Brno, Czech Republic. .,Department of Anatomy, Division of Neuroanatomy, Faculty of Medicine, Masaryk University, Kamenice 3, 62500, Brno, Czech Republic.
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Transcriptome Analysis of Chemically-Induced Sensory Neuron Ablation in Zebrafish. PLoS One 2016; 11:e0148726. [PMID: 26863206 PMCID: PMC4749159 DOI: 10.1371/journal.pone.0148726] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 01/22/2016] [Indexed: 12/31/2022] Open
Abstract
Peripheral glia are known to have a critical role in the initial response to axon damage and degeneration. However, little is known about the cellular responses of non-myelinating glia to nerve injury. In this study, we analyzed the transcriptomes of wild-type and mutant (lacking peripheral glia) zebrafish larvae that were treated with metronidazole. This treatment allowed us to conditionally and selectively ablate cranial sensory neurons whose axons are ensheathed only by non-myelinating glia. While transcripts representing over 27,000 genes were detected by RNAseq, only a small fraction (~1% of genes) were found to be differentially expressed in response to neuronal degeneration in either line at either 2 hrs or 5 hrs of metronidazole treatment. Analysis revealed that most expression changes (332 out of the total of 458 differentially expressed genes) occurred over a continuous period (from 2 to 5 hrs of metronidazole exposure), with a small number of genes showing changes limited to only the 2 hr (55 genes) or 5 hr (71 genes) time points. For genes with continuous alterations in expression, some of the most meaningful sets of enriched categories in the wild-type line were those involving the inflammatory TNF-alpha and IL6 signaling pathways, oxidoreductase activities and response to stress. Intriguingly, these changes were not observed in the mutant line. Indeed, cluster analysis indicated that the effects of metronidazole treatment on gene expression was heavily influenced by the presence or absence of glia, indicating that the peripheral non-myelinating glia play a significant role in the transcriptional response to sensory neuron degeneration. This is the first transcriptome study of metronidazole-induced neuronal death in zebrafish and the response of non-myelinating glia to sensory neuron degeneration. We believe this study provides important insight into the mechanisms by which non-myelinating glia react to neuronal death and degeneration in sensory circuits.
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Computational functional genomics based analysis of pain-relevant micro-RNAs. Hum Genet 2015; 134:1221-38. [DOI: 10.1007/s00439-015-1600-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 09/01/2015] [Indexed: 02/07/2023]
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Kambiz S, Brakkee E, Duraku L, Hovius S, Ruigrok T, Walbeehm E. Mirror-image pain after nerve reconstruction in rats is related to enhanced density of epidermal peptidergic nerve fibers. Exp Neurol 2015; 267:87-94. [DOI: 10.1016/j.expneurol.2015.02.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 01/17/2015] [Accepted: 02/10/2015] [Indexed: 11/24/2022]
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Chung MK, Asgar J, Lee J, Shim MS, Dumler C, Ro JY. The role of TRPM2 in hydrogen peroxide-induced expression of inflammatory cytokine and chemokine in rat trigeminal ganglia. Neuroscience 2015; 297:160-9. [PMID: 25849615 DOI: 10.1016/j.neuroscience.2015.03.067] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Accepted: 03/31/2015] [Indexed: 12/30/2022]
Abstract
Trigeminal ganglia (TG) contain neuronal cell bodies surrounded by satellite glial cells. Although peripheral injury is well known to induce changes in gene expression within sensory ganglia, detailed mechanisms whereby peripheral injury leads to gene expression within sensory ganglia are not completely understood. Reactive oxygen species (ROS) are an important modulator of hyperalgesia, but the role of ROS generated within sensory ganglia is unclear. Since ROS are known to affect transcription processes, ROS generated within sensory ganglia could directly influence gene expression and induce cellular changes at the soma level. In this study, we hypothesized that peripheral inflammation leads to cytokine and chemokine production and ROS generation within TG and that transient receptor potential melastatin (TRPM2), a well known oxidative sensor, contributes to ROS-induced gene regulation within TG. The masseter injection of complete Freund's adjuvant (CFA) resulted in a significantly elevated level of ROS within TG of the inflamed side with a concurrent increase in cytokine expression in TG. Treatment of TG cultures with H2O2 significantly up-regulated mRNA and protein levels of cytokine/chemokine such as interleukin 6 (IL-6) and chemokine (C-X-C motif) ligand 2 (CXCL2). TRPM2 was expressed in both neurons and non-neuronal cells in TG, and pretreatment of TG cultures with 2-aminoethoxydiphenyl borate (2-APB), an inhibitor of TRPM2, or siRNA against TRPM2 attenuated H2O2-induced up-regulation of IL-6 and CXCL2. These results suggested that activation of TRPM2 could play an important role in the modulation of cytokine/chemokine expression within TG under oxidative stress and that such changes may contribute to amplification of nociceptive signals leading to pathological pain conditions.
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Affiliation(s)
- M-K Chung
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, Program in Neuroscience, United States
| | - J Asgar
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, Program in Neuroscience, United States
| | - J Lee
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, Program in Neuroscience, United States
| | - M S Shim
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, Program in Neuroscience, United States
| | - C Dumler
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, Program in Neuroscience, United States
| | - J Y Ro
- University of Maryland School of Dentistry, Department of Neural and Pain Sciences, Program in Neuroscience, United States.
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Feng Q, Wang YI, Yang Y. Neuroprotective effect of interleukin-6 in a rat model of cerebral ischemia. Exp Ther Med 2015; 9:1695-1701. [PMID: 26136879 DOI: 10.3892/etm.2015.2363] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2014] [Accepted: 03/04/2015] [Indexed: 11/06/2022] Open
Abstract
Interleukin (IL)-6 is known to be a key cytokine in immune regulation in addition to serving crucial functions in various autoimmune diseases; however, the neuroprotective potential of IL-6 has not been fully investigated. The aim of the present study was to investigate the neuroprotective effects of the inflammatory cytokine IL-6 in a rat model of cerebral ischemia. Rat cerebral ischemia was induced by intraluminal middle cerebral artery occlusion. Following treatment with 500 or 50 ng IL-6, the infarct volumes and symptoms of neurological deficit were ameliorated. Furthermore, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining suggested that the IL-6 treatment reduced neuronal apoptosis in vivo, which was consistent with a lower percentage of annexin V- and caspase-3-positive cortical neurons. In addition, IL-6 in vitro induced the phosphorylation of signal transducer and activator of transcription (STAT) 3 and the expression of induced myeloid leukemia cell differentiation protein Mcl-1, but not the expression of B-cell lymphoma 2, suggesting the activation of the Janus kinase/STAT pathway by IL-6. IL-6 also appeared to be involved in the regulation of cytokine secretion and blood-brain barrier (BBB) integrity in cerebral ischemia. IL-6 downregulated a number of inflammatory cytokines, including tumor necrosis factor-α and IL-1β, as well as myeloperoxidase activity, indicating the accumulation of granulocytes in the ischemic brain tissue. IL-6 was also observed to support the integrity of the BBB by reducing Evans blue leakage in vivo and suppressing the expression of matrix metalloproteinase-9 in ischemic brain tissue. In conclusion, the results of the present study indicate that the neuroprotective effects of IL-6 in cerebral ischemia are the result of a range of processes, including the modulation of cell apoptosis, cytokine secretion and the integrity of the BBB. IL-6 could therefore be used as a therapeutic agent in clinical practice.
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Affiliation(s)
- Qilin Feng
- Department of Pharmacy, Central Hospital of Wuhan, Wuhan, Hubei 430030, P.R. China
| | - Y I Wang
- Department of Pharmacy, Central Hospital of Wuhan, Wuhan, Hubei 430030, P.R. China
| | - Yingda Yang
- School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
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Cao J, Li Z, Zhang Z, Ren X, Zhao Q, Shao J, Li M, Wang J, Huang P, Zang W. Intrathecal injection of fluorocitric acid inhibits the activation of glial cells causing reduced mirror pain in rats. BMC Anesthesiol 2014; 14:119. [PMID: 25598703 PMCID: PMC4297429 DOI: 10.1186/1471-2253-14-119] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2014] [Accepted: 12/11/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Growing evidence has shown that unilateral nerve injury results in pain hypersensitivity in the ipsilateral and contralateral sides respective to the injury site. This phenomenon is known as mirror image pain (MIP). Glial cells have been indicated in the mechanism of MIP; however, it is not clear how glial cells are involved in MIP. METHODS To observe phenomenon MIP and the following mechanism, 20 adult male Sprague-Dawley rats (weighing 180-220 g) were separated into two groups: Sham Group (n = 10) and left L5 spinal nerve ligated and sectioned (SNL) group (n = 10). Thermal hyperalgesia and mechanical hypersensitivity were measured for both groups to determine if the SNL model had Mirror image of Pain (MIP). Nav1.7 protein expression in DRG was analyzed using immunohistochemistry and western-blotting. And then to observe the effect of fluorocitrate on MIP, 15 rats were separated into three Groups: Sham Group (n = 5); SNL + FC group: intrathecal injection of Fluorocitric acid(FC) 1 nmol/10 μL (n = 5); SNL + NS group: intrathecal injection of 0.9% Normal Saline (n = 5). Behavior testing, immunocytochemistry, and western-blotting using dorsal root ganglion (DRG) from both sides were then conducted. RESULTS The results showed pain hypersensitivity in both hind-paws of the SNL animals, Mechanical tests showed the paw withdrawal threshold dropped from 13.30 ± 1.204 g to 2.57 ± 1.963 g at 14 d as will as the ipsilateral paw thermal withdrawal threshold dropped from 16.5 ± 2.236 s to 4.38 ± 2.544 s at 14 d. Mechanical tests showed the contralateral paw withdrawal threshold dropped from 14.01 ± 1.412 to 4.2 ± 1.789 g at 7d will the thermal withdrawal threshold dropped from 16.8 ± 2.176 s to 7.6 ± 1.517 s at 7d. Nav1.7 expression increased and glial cells actived in bilateral side DRG after SNL compared with sham group. After intrathecal injection of fluorocitrate, the glial cell in bilateral DRG were inhibited and the pain behavior were reversed in both hindpaws too. CONCLUSIONS Fluorocitrate can inhibit the activation of glial cells in spinal cord and DRG, and reduce MIP.
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Affiliation(s)
- Jing Cao
- Department of Basic Medical Sciences, Laboratory of Anatomy, Zhengzhou University, Zhengzhou, 450001 Henan Province China
| | - Zhihua Li
- Department of Basic Medical Sciences, Laboratory of Anatomy, Zhengzhou University, Zhengzhou, 450001 Henan Province China
| | - Zhenhua Zhang
- Department of Basic Medical Sciences, Laboratory of Anatomy, Zhengzhou University, Zhengzhou, 450001 Henan Province China
| | - Xiuhua Ren
- Department of Basic Medical Sciences, Laboratory of Anatomy, Zhengzhou University, Zhengzhou, 450001 Henan Province China
| | - Qingzan Zhao
- Department of Basic Medical Sciences, Laboratory of Anatomy, Zhengzhou University, Zhengzhou, 450001 Henan Province China
| | - Jinping Shao
- Department of Basic Medical Sciences, Laboratory of Anatomy, Zhengzhou University, Zhengzhou, 450001 Henan Province China
| | - Ming Li
- Department of Basic Medical Sciences, Laboratory of Anatomy, Zhengzhou University, Zhengzhou, 450001 Henan Province China
| | - Jiannan Wang
- Department of Basic Medical Sciences, Laboratory of Anatomy, Zhengzhou University, Zhengzhou, 450001 Henan Province China
| | - Puchao Huang
- Department of Basic Medical Sciences, Laboratory of Anatomy, Zhengzhou University, Zhengzhou, 450001 Henan Province China
| | - Weidong Zang
- Department of Basic Medical Sciences, Laboratory of Anatomy, Zhengzhou University, Zhengzhou, 450001 Henan Province China
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