1
|
García G, Martínez-Magaña CJ, Oviedo N, Granados-Soto V, Murbartián J. Bestrophin-1 Participates in Neuropathic Pain Induced by Spinal Nerve Transection but not Spinal Nerve Ligation. THE JOURNAL OF PAIN 2022; 24:689-705. [PMID: 36521670 DOI: 10.1016/j.jpain.2022.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 11/21/2022] [Accepted: 12/07/2022] [Indexed: 12/15/2022]
Abstract
Previous studies have reported that L5/L6 spinal nerve ligation (SNL), but not L5 spinal nerve transection (SNT), enhances anoctamin-1 in injured and uninjured dorsal root ganglia (DRG) of rats suggesting some differences in function of the type of nerve injury. The role of bestrophin-1 in these conditions is unknown. The aim of this study was to investigate the role of bestrophin-1 in rats subjected to L5 SNT and L5/L6 SNL. SNT up-regulated bestrophin-1 protein expression in injured L5 and uninjured L4 DRG at day 7, whereas it enhanced GAP43 mainly in injured, but also in uninjured DRG. In contrast, SNL enhanced GAP43 at day 1 and 7, while bestrophin-1 expression increased only at day 1 after nerve injury. Accordingly, intrathecal injection of the bestrophin-1 blocker CaCCinh-A01 (1-10 µg) reverted SNT- or SNL-induced tactile allodynia in a concentration-dependent manner. Intrathecal injection of CaCCinh-A01 (10 µg) prevented SNT-induced upregulation of bestrophin-1 and GAP43 at day 7. In contrast, CaCCinh-A01 did not affect SNL-induced up-regulation of GAP43 nor bestrophin-1. Bestrophin-1 was mainly expressed in small- and medium-size neurons in naïve rats, while SNT increased bestrophin-1 immunoreactivity in CGRP+, but not in IB4+ neuronal cells in DRG. Intrathecal injection of bestrophin-1 plasmid (pCMVBest) induced tactile allodynia and increased bestrophin-1 expression in DRG and spinal cord in naïve rats. CaCCinh-A01 reversed bestrophin-1 overexpression-induced tactile allodynia and restored bestrophin-1 expression. Our data suggest that bestrophin-1 plays a relevant role in neuropathic pain induced by SNT, but not by SNL. PERSPECTIVE: SNT, but not SNL, up-regulates bestrophin-1 and GAP43 protein expression in injured L5 and uninjured L4 DRG. SNT increases bestrophin-1 immunoreactivity in CGRP+ neurons in DRG. Bestrophin-1 overexpression induces allodynia. CaCCinh-A01 reduces allodynia and restores bestrophin-1 expression. Our data suggest bestrophin-1 is differentially regulated depending on the neuropathic pain model.
Collapse
Affiliation(s)
| | | | - Norma Oviedo
- Unidad de Investigación Médica en Inmunología e Infectología, Centro Médico Nacional, La Raza, IMSS. Mexico City, Mexico
| | - Vinicio Granados-Soto
- Neurobiology of Pain Laboratory, Departamento de Farmacobiología, Cinvestav, Mexico City, Mexico
| | - Janet Murbartián
- Departamento de Farmacobiología, Cinvestav, Mexico City, Mexico.
| |
Collapse
|
2
|
Chao D, Mecca CM, Yu G, Segel I, Gold MS, Hogan QH, Pan B. Dorsal root ganglion stimulation of injured sensory neurons in rats rapidly eliminates their spontaneous activity and relieves spontaneous pain. Pain 2021; 162:2917-2932. [PMID: 33990112 PMCID: PMC8486885 DOI: 10.1097/j.pain.0000000000002284] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 03/23/2021] [Indexed: 11/26/2022]
Abstract
ABSTRACT Dorsal root ganglion field stimulation (GFS) relieves evoked and spontaneous neuropathic pain by use-dependent blockade of impulse trains through the sensory neuron T-junction, which becomes complete within less than 1 minute for C-type units, also with partial blockade of Aδ units. We used this tool in the spinal nerve ligation (SNL) rat model to selectively block sensory neuron spontaneous activity (SA) of axotomized neurons at the fifth lumbar (L5) level vs blockade of units at the L4 level that remain uninjured but exposed to inflammation. In vivo dorsal root single-unit recordings after SNL showed increased SA in L5 units but not L4 units. Ganglion field stimulation blocked this SA. Ganglion field stimulation delivered at the L5 dorsal root ganglion blocked mechanical hyperalgesia behavior, mechanical allodynia, and ongoing spontaneous pain indicated by conditioned place preference, whereas GFS at L4 blocked evoked pain behavior but not spontaneous pain. In vivo single-unit recordings of spinal cord dorsal horn (DH) wide-dynamic-range neurons showed elevated SA after SNL, which was reduced by GFS at the L5 level but not by GFS at the L4 level. In addition, L5 GFS, but not L4 GFS, increased mechanical threshold of DH units during cutaneous mechanical stimulation, while L5 GFS exceeded L4 GFS in reducing evoked firing rates. Our results indicate that SA in injured neurons supports increased firing of DH wide-dynamic-range neurons, contributing to hyperalgesia, allodynia, and ongoing pain. Ganglion field stimulation analgesic effects after nerve injury are at least partly attributable to blocking propagation of this SA.
Collapse
Affiliation(s)
- Dongman Chao
- Department of Anesthesiology, Medical College of Wisconsin, 8701 W Watertown Plank Rd, Milwaukee, WI 53226
| | - Christina M. Mecca
- Department of Anesthesiology, Medical College of Wisconsin, 8701 W Watertown Plank Rd, Milwaukee, WI 53226
| | - Guoliang Yu
- Department of Anesthesiology, Medical College of Wisconsin, 8701 W Watertown Plank Rd, Milwaukee, WI 53226
| | - Ian Segel
- Department of Anesthesiology, Medical College of Wisconsin, 8701 W Watertown Plank Rd, Milwaukee, WI 53226
| | - Michael S. Gold
- Department of Neurobiology, University of Pittsburgh, 3500 Terrace Street Rm E1440 BST, Pittsburgh, PA 15213
| | - Quinn H. Hogan
- Department of Anesthesiology, Medical College of Wisconsin, 8701 W Watertown Plank Rd, Milwaukee, WI 53226
| | - Bin Pan
- Department of Anesthesiology, Medical College of Wisconsin, 8701 W Watertown Plank Rd, Milwaukee, WI 53226
| |
Collapse
|
3
|
Comparative Transcriptome Profiling Reveals Changes of microRNAs Response to Exercise in Rats with Neuropathic Pain. Neural Plast 2021; 2021:5597139. [PMID: 34394340 PMCID: PMC8356008 DOI: 10.1155/2021/5597139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 06/24/2021] [Accepted: 07/16/2021] [Indexed: 11/18/2022] Open
Abstract
There is accumulating evidence showing that exercise therapy may play an active role in peripheral neuropathic pain (NP), but its mechanism is still unclear. Studies have found that microRNAs (miRNAs) may play a role in NP by regulating pain-related target genes. Therefore, we aimed to explore the changes of miRNA and mRNA of dorsal root ganglion (DRG) after NP in response to exercise with transcriptome technology. The chronic constriction injury (CCI) model was established, and rats were randomly allocated into three groups, namely, the sham-operated, CCI, and CCI-exercised groups. L4-L6 DRG tissue was taken for RNA-sequencing, and the differentially expressed genes (DEGs) were determined through bioinformatics analysis. Real-time PCR was used to confirm the accuracy. A total of 4 overlapping differentially expressed miRNAs and 186 overlapping differentially expressed mRNAs were identified in the two comparisons of the sham-operated group versus the CCI group and the CCI group versus the CCI-exercised group. Among these DEGs, miR-145-5p, miR-341, miR-300-5p, miR-653-5p, Atf3, Cacna2d1, Gal, and Ctss related to NP were validated by real-time PCR. DEGs between the CCI and CCI-exercised groups were enriched in HIF-1 signaling pathway, Rap1 signaling pathway, and neurotrophin signaling pathway. This study provides an understanding of the adaptive mechanisms after exercise of NP, and these DEGs in DRG might play a role in NP by stimulating the enriched pathways.
Collapse
|
4
|
Chang CH, Chang YS, Hsieh YL. Transient receptor potential vanilloid subtype 1 depletion mediates mechanical allodynia through cellular signal alterations in small-fiber neuropathy. Pain Rep 2021; 6:e922. [PMID: 34585035 PMCID: PMC8462592 DOI: 10.1097/pr9.0000000000000922] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 01/22/2021] [Accepted: 02/22/2021] [Indexed: 12/27/2022] Open
Abstract
Transient receptor potential vanilloid subtype 1 (TRPV1) is a polymodal nociceptor that monitors noxious thermal sensations. Few studies have addressed the role of TRPV1 in mechanical allodynia in small-fiber neuropathy (SFN) caused by sensory nerve damage. Accordingly, this article reviews the putative mechanisms of TRPV1 depletion that mediates mechanical allodynia in SFN. The intraepidermal nerve fibers (IENFs) degeneration and sensory neuronal injury are the primary characteristics of SFN. Intraepidermal nerve fibers are mainly C-polymodal nociceptors and Aδ-fibers, which mediated allodynic pain after neuronal sensitization. TRPV1 depletion by highly potent neurotoxins induces the upregulation of activating transcription factor 3 and IENFs degeneration which mimics SFN. TRPV1 is predominately expressed by the peptidergic than nonpeptidergic nociceptors, and these neurochemical discrepancies provided the basis of the distinct pathways of thermal analgesia and mechanical allodynia. The depletion of peptidergic nociceptors and their IENFs cause thermal analgesia and sensitized nonpeptidergic nociceptors respond to mechanical allodynia. These distinct pathways of noxious stimuli suggested determined by the neurochemical-dependent neurotrophin cognate receptors such as TrkA and Ret receptors. The neurogenic inflammation after TRPV1 depletion also sensitized Ret receptors which results in mechanical allodynia. The activation of spinal TRPV1(+) neurons may contribute to mechanical allodynia. Also, an imbalance in adenosinergic analgesic signaling in sensory neurons such as the downregulation of prostatic acid phosphatase and adenosine A1 receptors, which colocalized with TRPV1 as a membrane microdomain also correlated with the development of mechanical allodynia. Collectively, TRPV1 depletion-induced mechanical allodynia involves a complicated cascade of cellular signaling alterations.
Collapse
Affiliation(s)
- Chin-Hong Chang
- Department of Surgery, Chi Mei Medical Center, Tainan, Taiwan
| | - Ying-Shuang Chang
- Department of Anatomy, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yu-Lin Hsieh
- Department of Anatomy, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- School of Post-Baccalaureate Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| |
Collapse
|
5
|
A modulator of the low-voltage-activated T-type calcium channel that reverses HIV glycoprotein 120-, paclitaxel-, and spinal nerve ligation-induced peripheral neuropathies. Pain 2021; 161:2551-2570. [PMID: 32541387 DOI: 10.1097/j.pain.0000000000001955] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The voltage-gated calcium channels CaV3.1-3.3 constitute the T-type subfamily, whose dysfunctions are associated with epilepsy, psychiatric disorders, and chronic pain. The unique properties of low-voltage-activation, faster inactivation, and slower deactivation of these channels support their role in modulation of cellular excitability and low-threshold firing. Thus, selective T-type calcium channel antagonists are highly sought after. Here, we explored Ugi-azide multicomponent reaction products to identify compounds targeting T-type calcium channel. Of the 46 compounds tested, an analog of benzimidazolonepiperidine-5bk (1-{1-[(R)-{1-[(1S)-1-phenylethyl]-1H-1,2,3,4-tetrazol-5-yl}(thiophen-3-yl)methyl]piperidin-4-yl}-2,3-dihydro-1H-1,3-benzodiazol-2-one) modulated depolarization-induced calcium influx in rat sensory neurons. Modulation of T-type calcium channels by 5bk was further confirmed in whole-cell patch clamp assays in dorsal root ganglion (DRG) neurons, where pharmacological isolation of T-type currents led to a time- and concentration-dependent regulation with a low micromolar IC50. Lack of an acute effect of 5bk argues against a direct action on T-type channels. Genetic knockdown revealed CaV3.2 to be the isoform preferentially modulated by 5bk. High voltage-gated calcium, as well as tetrodotoxin-sensitive and -resistant sodium, channels were unaffected by 5bk. 5bk inhibited spontaneous excitatory postsynaptic currents and depolarization-evoked release of calcitonin gene-related peptide from lumbar spinal cord slices. Notably, 5bk did not bind human mu, delta, or kappa opioid receptors. 5bk reversed mechanical allodynia in rat models of HIV-associated neuropathy, chemotherapy-induced peripheral neuropathy, and spinal nerve ligation-induced neuropathy, without effects on locomotion or anxiety. Thus, 5bk represents a novel T-type modulator that could be used to develop nonaddictive pain therapeutics.
Collapse
|
6
|
Studies on CRMP2 SUMOylation-deficient transgenic mice identify sex-specific Nav1.7 regulation in the pathogenesis of chronic neuropathic pain. Pain 2021; 161:2629-2651. [PMID: 32569093 DOI: 10.1097/j.pain.0000000000001951] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The sodium channel Nav1.7 is a master regulator of nociceptive input into the central nervous system. Mutations in this channel can result in painful conditions and produce insensitivity to pain. Despite being recognized as a "poster child" for nociceptive signaling and human pain, targeting Nav1.7 has not yet produced a clinical drug. Recent work has illuminated the Nav1.7 interactome, offering insights into the regulation of these channels and identifying potentially new druggable targets. Among the regulators of Nav1.7 is the cytosolic collapsin response mediator protein 2 (CRMP2). CRMP2, modified at lysine 374 (K374) by addition of a small ubiquitin-like modifier (SUMO), bound Nav1.7 to regulate its membrane localization and function. Corollary to this, preventing CRMP2 SUMOylation was sufficient to reverse mechanical allodynia in rats with neuropathic pain. Notably, loss of CRMP2 SUMOylation did not compromise other innate functions of CRMP2. To further elucidate the in vivo role of CRMP2 SUMOylation in pain, we generated CRMP2 K374A knock-in (CRMP2) mice in which Lys374 was replaced with Ala. CRMP2 mice had reduced Nav1.7 membrane localization and function in female, but not male, sensory neurons. Behavioral appraisal of CRMP2 mice demonstrated no changes in depressive or repetitive, compulsive-like behaviors and a decrease in noxious thermal sensitivity. No changes were observed in CRMP2 mice to inflammatory, acute, or visceral pain. By contrast, in a neuropathic model, CRMP2 mice failed to develop persistent mechanical allodynia. Our study suggests that CRMP2 SUMOylation-dependent control of peripheral Nav1.7 is a hallmark of chronic, but not physiological, neuropathic pain.
Collapse
|
7
|
Tran EL, Crawford LK. Revisiting PNS Plasticity: How Uninjured Sensory Afferents Promote Neuropathic Pain. Front Cell Neurosci 2020; 14:612982. [PMID: 33362476 PMCID: PMC7759741 DOI: 10.3389/fncel.2020.612982] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 11/12/2020] [Indexed: 11/13/2022] Open
Abstract
Despite the widespread study of how injured nerves contribute to chronic pain, there are still major gaps in our understanding of pain mechanisms. This is particularly true of pain resulting from nerve injury, or neuropathic pain, wherein tactile or thermal stimuli cause painful responses that are particularly difficult to treat with existing therapies. Curiously, this stimulus-driven pain relies upon intact, uninjured sensory neurons that transmit the signals that are ultimately sensed as painful. Studies that interrogate uninjured neurons in search of cell-specific mechanisms have shown that nerve injury alters intact, uninjured neurons resulting in an activity that drives stimulus-evoked pain. This review of neuropathic pain mechanisms summarizes cell-type-specific pathology of uninjured sensory neurons and the sensory ganglia that house their cell bodies. Uninjured neurons have demonstrated a wide range of molecular and neurophysiologic changes, many of which are distinct from those detected in injured neurons. These intriguing findings include expression of pain-associated molecules, neurophysiological changes that underlie increased excitability, and evidence that intercellular signaling within sensory ganglia alters uninjured neurons. In addition to well-supported findings, this review also discusses potential mechanisms that remain poorly understood in the context of nerve injury. This review highlights key questions that will advance our understanding of the plasticity of sensory neuron subpopulations and clarify the role of uninjured neurons in developing anti-pain therapies.
Collapse
Affiliation(s)
- Emily L Tran
- Department of Pathobiological Sciences, University of Wisconsin-Madison School of Veterinary Medicine, Madison, WI, United States
| | - LaTasha K Crawford
- Department of Pathobiological Sciences, University of Wisconsin-Madison School of Veterinary Medicine, Madison, WI, United States
| |
Collapse
|
8
|
Javed H, Rehmathulla S, Tariq S, Emerald BS, Ljubisavljevic M, Shehab S. Perineural application of resiniferatoxin on uninjured L3 and L4 nerves completely alleviates thermal and mechanical hypersensitivity following L5 nerve injury in rats. J Comp Neurol 2020; 528:2195-2217. [PMID: 32064609 DOI: 10.1002/cne.24884] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 02/11/2020] [Accepted: 02/12/2020] [Indexed: 12/21/2022]
Abstract
Fifth lumbar (L5) nerve injury in rats causes neuropathic pain manifested with thermal and mechanical hypersensitivity in the ipsilateral hind paw. This study aimed to determine whether the elimination of unmyelinated primary afferents of the adjacent uninjured nerves (L3 and L4) would alleviate peripheral neuropathic pain. Different concentrations of capsaicin or its analog, resiniferatoxin (RTX), were applied perineurally on either the left L4 or L3 and L4 nerves in Wistar rats whose left L5 nerves were ligated and cut. The application of both capsaicin and RTX on the L4 nerve significantly reduced both thermal and mechanical hypersensitivity. However, only the application of RTX on both L3 and L4 nerves completely alleviated all neuropathic manifestations. Interestingly, responses to thermal and mechanical stimuli were preserved, despite RTX application on uninjured L3, L4, and L5 nerves, which supply the plantar skin in rats. Perineural application of RTX caused downregulation of TRPV1, CGRP, and IB4 binding and upregulation of VIP in the corresponding dorsal root ganglia (DRG) and the dorsal horn of the spinal cord. In comparison, VGLUT1 and NPY immunoreactivities were not altered. RTX application did not cause degenerative or ultrastructural changes in the treated nerves and corresponding DRGs. The results demonstrate that RTX induces neuroplasticity, rather than structural changes in primary afferents, that are responsible for alleviating hypersensitivity and chronic pain. Furthermore, this study suggests that treating uninjured adjacent spinal nerves may be used to manage chronic neuropathic pain following peripheral nerve injury.
Collapse
Affiliation(s)
- Hayate Javed
- Department of Anatomy, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Sumisha Rehmathulla
- Department of Anatomy, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Saeed Tariq
- Department of Anatomy, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Bright S Emerald
- Department of Anatomy, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Milos Ljubisavljevic
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Safa Shehab
- Department of Anatomy, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates.,Zayed Center for Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| |
Collapse
|
9
|
García G, Noriega-Navarro R, Martínez-Rojas VA, Gutiérrez-Lara EJ, Oviedo N, Murbartián J. Spinal TASK-1 and TASK-3 modulate inflammatory and neuropathic pain. Eur J Pharmacol 2019; 862:172631. [DOI: 10.1016/j.ejphar.2019.172631] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 08/09/2019] [Accepted: 08/27/2019] [Indexed: 12/13/2022]
|
10
|
Shinoda M, Fukuoka T, Takeda M, Iwata K, Noguchi K. Spinal glial cell line-derived neurotrophic factor infusion reverses reduction of Kv4.1-mediated A-type potassium currents of injured myelinated primary afferent neurons in a neuropathic pain model. Mol Pain 2019; 15:1744806919841196. [PMID: 30868936 PMCID: PMC6463340 DOI: 10.1177/1744806919841196] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
High frequency spontaneous activity in injured primary afferents has been proposed as a pathological mechanism of neuropathic pain following nerve injury. Although spinal infusion of glial cell line-derived neurotrophic factor reduces the activity of injured myelinated A-fiber neurons after fifth lumbar (L5) spinal nerve ligation in rats, the implicated molecular mechanism remains undetermined. The fast-inactivating transient A-type potassium current (IA) is an important determinant of neuronal excitability, and five voltage-gated potassium channel (Kv) alpha-subunits, Kv1.4, Kv3.4, Kv4.1, Kv4.2, and Kv4.3, display IA in heterologous expression systems. Here, we examined the effect of spinal glial cell line-derived neurotrophic factor infusion on IA and the expression of these five Kv mRNAs in injured A-fiber neurons using the in vitro patch clamp technique and in situ hybridization histochemistry. Glial cell line-derived neurotrophic factor infusion reversed axotomy-induced reduction of the rheobase, elongation of first spike duration, and depolarization of the resting membrane potential. L5 spinal nerve ligation significantly reduced the current density of IA and glial cell line-derived neurotrophic factor treatment reversed the reduction. Among the examined Kv mRNAs, only the change in Kv4.1-expression was parallel with the change in IA after spinal nerve ligation and glial cell line-derived neurotrophic factor treatment. These findings suggest that glial cell line-derived neurotrophic factor should reduce the hyperexcitability of injured A-fiber primary afferents by IA recurrence. Among the five IA-related Kv channels, Kv4.1 should be a key channel, which account for this IA recurrence.
Collapse
Affiliation(s)
- Masamichi Shinoda
- 1 Department of Physiology, Nihon University School of Dentistry, Surugadai, Chiyoda-ku, Tokyo, Japan
| | - Tetsuo Fukuoka
- 2 Department of Anatomy and Neuroscience, Hyogo College of Medicine, Mukogawa-cho, Nishinomiya, Hyogo, Japan.,3 Fukuoka Clinic, Kasuga, Suita, Osaka, Japan
| | - Mamoru Takeda
- 4 Laboratory of Food and Physiological Sciences, Department of Life and Food Sciences, School of Life and Environmental Sciences, Azabu University, Fuchinobe, Chuo-ku, Sagamihara, Japan
| | - Koichi Iwata
- 1 Department of Physiology, Nihon University School of Dentistry, Surugadai, Chiyoda-ku, Tokyo, Japan
| | - Koichi Noguchi
- 2 Department of Anatomy and Neuroscience, Hyogo College of Medicine, Mukogawa-cho, Nishinomiya, Hyogo, Japan
| |
Collapse
|
11
|
Chang YS, Kan HW, Hsieh YL. Activating transcription factor 3 modulates protein kinase C epsilon activation in diabetic peripheral neuropathy. J Pain Res 2019; 12:317-326. [PMID: 30679921 PMCID: PMC6338122 DOI: 10.2147/jpr.s186699] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Background Skin denervation that develops in patients with diabetes mellitus as a neuropathic manifestation is known as diabetic peripheral neuropathy (DPN). Skin denervation is parallel to neuronal injuries that alter intracellular signaling. To date, the correlation between nerve injury and the activation of intracellular responses to neuropathic manifestations has not been elucidated; specifically, whether activating transcription factor 3 (ATF3) is responsible for neuronal injury and a critical molecule that modulates the activation of intracellular protein kinase C epsilon (p-PKCε) and pain development in DPN is a crucial question. Methods To address, ATF3 knockout (atf3−/− group, C57/B6 genetic background) and wild-type mice (atf3+/+ group) received a single dose of streptozotocin (200 mg/kg) to generate a mouse model of DPN. Results Both atf3+/+ and atf3−/− mice exhibited hyperglycemia and the same pathology of skin denervation at posttreatment month 2, but only atf3+/+ mice developed thermal hyperalgesia (P<0.001) and mechanical allodynia (P=0.002). The atf3+/+ group, but not the atf3−/− group, had preferential ATF3 upregulation on p-PKCε(+) neurons with a ratio of 37.7%±6.1% in p-PKCε(+):ATF3(+) neurons (P<0.001). In addition, B-cell lymphoma-extra large (Bcl-XL), an antiapoptotic Bcl2 family protein, exhibited parallel patterns to p-PKCε (ie, Bcl-XL upregulation was reversed in atf3−/− mice). These two molecules were colocalized and increased by approximately two-fold in the atf3+/+ group compared with the atf3−/− group (30.0%±3.4% vs 13.7% ± 6.2%, P=0.003). Furthermore, linear analysis results showed that the densities of p-PKCε and Bcl-XL had a reverse linear relationship with the degrees of thermal hyperalgesia and mechanical allodynia. Conclusion Collectively, this report suggested that ATF3 is a critical upstream molecule that modulates p-PKCε and Bcl-XL expression, which consequently mediated the development of neuropathic manifestation in DPN.
Collapse
Affiliation(s)
- Ying-Shuang Chang
- Department of Anatomy, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan,
| | - Hung-Wei Kan
- Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
| | - Yu-Lin Hsieh
- Department of Anatomy, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan, .,Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan,
| |
Collapse
|
12
|
García G, Martínez-Rojas VA, Oviedo N, Murbartián J. Blockade of anoctamin-1 in injured and uninjured nerves reduces neuropathic pain. Brain Res 2018; 1696:38-48. [DOI: 10.1016/j.brainres.2018.06.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Revised: 04/12/2018] [Accepted: 06/01/2018] [Indexed: 12/28/2022]
|
13
|
Salinas-Abarca AB, Velazquez-Lagunas I, Franco-Enzástiga Ú, Torres-López JE, Rocha-González HI, Granados-Soto V. ATF2, but not ATF3, participates in the maintenance of nerve injury-induced tactile allodynia and thermal hyperalgesia. Mol Pain 2018; 14:1744806918787427. [PMID: 29921170 PMCID: PMC6050803 DOI: 10.1177/1744806918787427] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Transcription factors are proteins that modulate the transcriptional rate of target genes in the nucleus in response to extracellular or cytoplasmic signals. Activating transcription factors 2 (ATF2) and 3 (ATF3) respond to environmental signals and maintain cellular homeostasis. There is evidence that inflammation and nerve injury modulate ATF2 and ATF3 expression. However, the function of these transcription factors in pain is unknown. The purpose of this study was to investigate the contribution of ATF2 and ATF3 to nerve injury-induced neuropathic pain. L5/6 spinal nerve ligation induced tactile allodynia and thermal hyperalgesia. Moreover, nerve damage enhanced ATF2 and ATF3 protein expression in injured L5/6 dorsal root ganglia and spinal cord but not in uninjured L4 dorsal root ganglia. Nerve damage also enhanced ATF2 immunoreactivity in dorsal root ganglia and spinal cord 7 to 21 days post-injury. Repeated intrathecal post-treatment with a small-interfering RNA targeted against ATF2 (ATF2 siRNA) or anti-ATF2 antibody partially reversed tactile allodynia and thermal hyperalgesia. In contrast, ATF3 siRNA or anti-ATF3 antibody did not modify nociceptive behaviors. ATF2 immunoreactivity was found in dorsal root ganglia and spinal cord co-labeling with NeuN mainly in non-peptidergic (IB4+) but also in peptidergic (CGRP+) neurons. ATF2 was found mainly in small- and medium-sized neurons. These results suggest that ATF2, but not ATF3, is found in strategic sites related to spinal nociceptive processing and participates in the maintenance of neuropathic pain in rats.
Collapse
Affiliation(s)
- Ana B Salinas-Abarca
- 1 Neurobiology of Pain Laboratory, Departamento de Farmacobiología, Cinvestav, Mexico
| | | | | | - Jorge E Torres-López
- 2 Laboratorio Mecanismos del Dolor, Centro de Investigación, División Académica de Ciencias de la Salud, Universidad Juárez Autónoma de Tabasco, Mexico.,3 Hospital Regional de Alta Especialidad Dr. Juan Graham Casasús, Mexico
| | - Héctor I Rocha-González
- 4 Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Mexico
| | - Vinicio Granados-Soto
- 1 Neurobiology of Pain Laboratory, Departamento de Farmacobiología, Cinvestav, Mexico
| |
Collapse
|
14
|
Upregulation of Ca v3.2 T-type calcium channels in adjacent intact L4 dorsal root ganglion neurons in neuropathic pain rats with L5 spinal nerve ligation. Neurosci Res 2018; 142:30-37. [PMID: 29684385 DOI: 10.1016/j.neures.2018.04.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 04/13/2018] [Accepted: 04/16/2018] [Indexed: 02/07/2023]
Abstract
Besides the injured peripheral dorsal root ganglion (DRG) neurons, the adjacent intact DRG neurons also have important roles in neuropathic pain. Ion channels including Cav3.2 T-type calcium channel in the DRG neurons are important in the development of neuropathic pain. In the present study, we aimed to examine the expression of Cav3.2 T-type calcium channels in the intact DRG neurons in neuropathic pain. A neuropathic pain model of rat with lumbar 5 (L5) spinal nerve ligation (SNL) was established, in which the L4 DRG was separated from the axotomized L5 DRG, and the molecular, morphological and electrophysiological changes of Cav3.2 T-type calcium channels in L4 DRG neurons were investigated. Western blotting showed that total and membrane protein levels of Cav3.2 in L4 DRG neurons increased, and voltage-dependent patch clamp recordings revealed an increased T-type current density with a curve shift to the left in steady-state activation in the acutely isolated L4 DRG neurons in neuropathic pain rats. Immunofluorescent staining further showed that the membrane expression of Cav3.2 increased in CGRP-, IB4-positive small neurons and NF200-positive large ones. In conclusion, the membrane expression and the function of Cav3.2 T-type calcium channels are increased in the intact L4 DRG neurons in neuropathic pain rats with peripheral nerve injury like SNL.
Collapse
|
15
|
Lee YC, Lu SC, Hsieh YL. Establishing a Mouse Model of a Pure Small Fiber Neuropathy with the Ultrapotent Agonist of Transient Receptor Potential Vanilloid Type 1. J Vis Exp 2018. [PMID: 29553496 DOI: 10.3791/56651] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Patients with diabetes mellitus (DM) or those experiencing the neurotoxic effects of chemotherapeutic agents may develop sensation disorders due to degeneration and injury of small-diameter sensory neurons, referred to as small fiber neuropathy. Present animal models of small fiber neuropathy affect both large- and small-diameter sensory fibers and thus create a neuropathology too complex to properly assess the effects of injured small-diameter sensory fibers. Therefore, it is necessary to develop an experimental model of pure small fiber neuropathy to adequately examine these issues. This protocol describes an experimental model of small fiber neuropathy specifically affecting small-diameter sensory nerves with resiniferatoxin (RTX), an ultrapotent agonist of transient receptor potential vanilloid type 1 (TRPV1), through a single dose of intraperitoneal injection, referred to as RTX neuropathy. This RTX neuropathy showed pathological manifestations and behavioral abnormalities that mimic the clinical characteristics of patients with small fiber neuropathy, including intraepidermal nerve fiber (IENF) degeneration, specifically injury in small-diameter neurons, and induction of thermal hypoalgesia and mechanical allodynia. This protocol tested three doses of RTX (200, 50, and 10 µg/kg, respectively) and concluded that a critical dose of RTX (50 µg/kg) is required for the development of typical small fiber neuropathy manifestations, and prepared a modified immunostaining procedure to investigate IENF degeneration and neuronal soma injury. The modified procedure is fast, systematic, and economic. Behavioral evaluation of neuropathic pain is critical to reveal the function of small-diameter sensory nerves. The evaluation of mechanical thresholds in experimental rodents is particularly challenging and this protocol describes a customized metal mesh that is suitable for this type of assessment in rodents. In summary, RTX neuropathy is a new and easily established experimental model to evaluate the molecular significance and intervention underlying neuropathic pain for the development of therapeutic agents.
Collapse
Affiliation(s)
- Yi-Chen Lee
- Department of Anatomy, School of Medicine, College of Medicine, Kaohsiung Medical University; Department of Medical Research, Kaohsiung Medical University Hospital
| | - Shui-Chin Lu
- Department of Medical Research, Ultrastructural Laboratory, Kaohsiung Medical University Hospital
| | - Yu-Lin Hsieh
- Department of Anatomy, School of Medicine, College of Medicine, Kaohsiung Medical University; Department of Medical Research, Kaohsiung Medical University Hospital;
| |
Collapse
|
16
|
Sanna MD, Mello T, Masini E, Galeotti N. Activation of ERK/CREB pathway in noradrenergic neurons contributes to hypernociceptive phenotype in H4 receptor knockout mice after nerve injury. Neuropharmacology 2018; 128:340-350. [DOI: 10.1016/j.neuropharm.2017.10.025] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 10/18/2017] [Accepted: 10/20/2017] [Indexed: 12/27/2022]
|
17
|
Qin S, Jiang F, Zhou Y, Zhou G, Ye P, Ji Y. Local knockdown of Nav1.6 relieves pain behaviors induced by BmK I. Acta Biochim Biophys Sin (Shanghai) 2017; 49:713-721. [PMID: 28655185 DOI: 10.1093/abbs/gmx064] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Accepted: 06/05/2017] [Indexed: 12/13/2022] Open
Abstract
Voltage-gated sodium channels (VGSCs) in peripheral nociceptive sensory neurons are critical to transmit pain signals. BmK I purified from the venom of scorpion Buthus martensi Karsch (BmK) has been demonstrated to be the primary contributor of envenomation-associated pain. However, the role of distinct VGSCs such as Nav1.6 in the induction and maintenance of pain behaviors induced by BmK I was ambiguous. Herein, using molecular and behavioral approaches we investigated the mRNA and protein expression profiles of Nav1.6 in rat DRG after intraplantar injection of BmK I and tested the pain behaviors after knockdown of Nav1.6 in BmK I-treated rats. It was shown that during induction and maintenance of pain responses induced by BmK I, the expression of Nav1.6 in DRG was found to be significantly increased at both mRNA and protein levels. The percentage of co-localization of Nav1.6 and Isolectin B4, a molecular marker of small diameter non-peptidergic DRG neurons, was increased at the maintenance phase of pain responses. Furthermore, spontaneous pain and mechanical allodynia, but not thermal hyperalgesia induced by BmK I, were significantly alleviated after knockdown of Nav1.6. These data strongly suggest that Nav1.6 plays an indispensable role in the peripheral pain hypersensitivity induced by BmK I.
Collapse
Affiliation(s)
- Shichao Qin
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai 200444, China
| | - Feng Jiang
- Shanghai Chongming Xinhua Translational Medical Institute for Cancer Pain, Shanghai 202150, China
| | - You Zhou
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai 200444, China
| | - Guokun Zhou
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai 200444, China
| | - Pin Ye
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai 200444, China
| | - Yonghua Ji
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai 200444, China
- Shanghai Chongming Xinhua Translational Medical Institute for Cancer Pain, Shanghai 202150, China
| |
Collapse
|
18
|
Noxious, but not innocuous, thermal stimuli evoke pERK expression in dorsal horn neurons after spared nerve injury in adult rats. Neurosci Lett 2017. [PMID: 28636927 DOI: 10.1016/j.neulet.2017.06.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Noxious stimulation of sensory afferents evokes phosphorylated extracellular signal regulated kinase (pERK) expression in spinal cord neurons. This study investigated the expression of pERK in the dorsal horn neurons in response to innocuous and noxious cold stimuli in naïve versus spared nerve injury (SNI) rats. Noxious cold or hot stimuli (0 or 45°C) elicited pERK expression in laminae I-II whereas cooling stimuli from 32°C to 25, 15 or 5°C produced no or little pERK expression in dorsal horn neurons. Five days after SNI, a time when these animals showed heat hyperalgesia, cold and mechanical hypersensitivity, only noxious heat stimuli produced a significant increase in pERK expression compared to naïve rats in spinal cord neurons. Thus, pERK cannot be used as an activity marker for neurons responding to cooling stimuli or cold allodynia; however, these results confirm the role of pERK as an activity marker for heat hyperalgesia.
Collapse
|
19
|
Acquired Exchange Protein Directly Activated by Cyclic Adenosine Monophosphate Activity Induced by p38 Mitogen-activated Protein Kinase in Primary Afferent Neurons Contributes to Sustaining Postincisional Nociception. Anesthesiology 2017; 126:150-162. [PMID: 27984207 DOI: 10.1097/aln.0000000000001401] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND The molecular mechanisms responsible for sustained pain after tissue injury are largely unknown. The aim of this study was to clarify the role of exchange protein directly activated by cyclic adenosine monophosphate (EPAC) in sustained postincisional nociception, using tissue injury-induced nociceptor priming, and involvement of p38 mitogen-activated protein kinase (p38MAPK) in EPAC-mediated nociceptor priming. METHODS Plantar incisions were made in the hind paws of Sprague-Dawley rats (n = 144). Nociceptor priming was confirmed by behavior testing followed by prostaglandin E2 injection 14 to 21 days after the incision. ESI-09, a selective EPAC inhibitor, was administered to assess its effects on nociceptor priming. Expression of two isoforms of EPAC (EPAC1/EPAC2) in dorsal root ganglions from naive rats and those 14 days after the incision was detected by immunohistochemistry and Western blotting. Separately, FR167653, a selective p38MAPK inhibitor, was administered to assess its effect on EPAC1/EPAC2 expression and the development of nociceptor priming. RESULTS Prostaglandin E2 injection 14 to 21 days after the plantar incision induced persistent mechanical hyperalgesia for 7 days. EPAC1/EPAC2 expression in dorsal root ganglion neurons was trivial in naive rats (7.7 ± 4.8% for EPAC1; 6.3 ± 4.1% for EPAC2) but markedly increased 14 days after the incision (21.0 ± 9.4% and 20.1 ± 3.8%, respectively). ESI-09 treatment inhibited prostaglandin E2-induced persistent mechanical hypersensitivity but had no effect on incision-induced acute nociceptive hypersensitivity. Treatment with FR167653 before the incision inhibited the development of nociceptor priming and incision-induced EPAC1/EPAC2 expression (8.5 ± 5.4% and 7.6 ± 3.3%, respectively). CONCLUSIONS Transient inflammatory stimulation causes long-lasting nociceptive hypersensitivity via nociceptor priming during the subacute period after incision. Acquired EPAC activity by p38MAPK in the dorsal root ganglion neurons is a key for this event.
Collapse
|
20
|
Ramachandra R, Elmslie KS. EXPRESS: Voltage-dependent sodium (NaV) channels in group IV sensory afferents. Mol Pain 2016; 12:12/0/1744806916660721. [PMID: 27385723 PMCID: PMC4956173 DOI: 10.1177/1744806916660721] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Patients with intermittent claudication suffer from both muscle pain and an exacerbated exercise pressor reflex. Excitability of the group III and group IV afferent fibers mediating these functions is controlled in part by voltage-dependent sodium (NaV) channels. We previously found tetrodotoxin-resistant NaV1.8 channels to be the primary type in muscle afferent somata. However, action potentials in group III and IV afferent axons are blocked by TTX, supporting a minimal role of NaV1.8 channels. To address these apparent differences in NaV channel expression between axon and soma, we used immunohistochemistry to identify the NaV channels expressed in group IV axons within the gastrocnemius muscle and the dorsal root ganglia sections. Positive labeling by an antibody against the neurofilament protein peripherin was used to identify group IV neurons and axons. We show that >67% of group IV fibers express NaV1.8, NaV1.6, or NaV1.7. Interestingly, expression of NaV1.8 channels in group IV somata was significantly higher than in the fibers, whereas there were no significant differences for either NaV1.6 or NaV1.7. When combined with previous work, our results suggest that NaV1.8 channels are expressed in most group IV axons, but that, under normal conditions, NaV1.6 and/or NaV1.7 play a more important role in action potential generation to signal muscle pain and the exercise pressor reflex.
Collapse
Affiliation(s)
- Renuka Ramachandra
- The Baker Laboratory of Pharmacology, Department of Pharmacology, AT Still University of Health Sciences, Kirksville, MO, USA
- Renuka Ramachandra, The Baker Laboratory of Pharmacology, Department of Pharmacology, Kirksville College of Osteopathic Medicine, AT Still University of Health Sciences, Kirksville, MO 63501, USA.
| | - Keith S Elmslie
- The Baker Laboratory of Pharmacology, Department of Pharmacology, AT Still University of Health Sciences, Kirksville, MO, USA
| |
Collapse
|
21
|
Medici T, Shortland PJ. Effects of peripheral nerve injury on parvalbumin expression in adult rat dorsal root ganglion neurons. BMC Neurosci 2015; 16:93. [PMID: 26674138 PMCID: PMC4681077 DOI: 10.1186/s12868-015-0232-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 12/07/2015] [Indexed: 12/24/2022] Open
Abstract
Background Parvalbumin (PV) is a calcium binding protein that identifies a subpopulation of proprioceptive dorsal root ganglion (DRG) neurons. Calcitonin gene-related peptide (CGRP) is also expressed in a high proportion of muscle afferents but its relationship to PV is unclear. Little is known of the phenotypic responses of muscle afferents to nerve injury. Sciatic nerve axotomy or L5 spinal nerve ligation and section (SNL) lesions were used to explore these issues in adult rats using immunocytochemistry. Results In naive animals, the mean PV expression was 25 % of L4 or L5 dorsal root ganglion (DRG) neurons, and this was unchanged 2 weeks after sciatic nerve axotomy. Colocalization studies with the injury marker activating transcription factor 3 (ATF3) showed that approximately 24 % of PV neurons expressed ATF3 after sciatic nerve axotomy suggesting that PV may show a phenotypic switch from injured to uninjured neurons. This possibility was further assessed using the spinal nerve ligation (SNL) injury model where injured and uninjured neurons are located in different DRGs. Two weeks after L5 SNL there was no change in total PV staining and essentially all L5 PV neurons expressed ATF3. Additionally, there was no increase in PV-ir in the adjacent uninjured L4 DRG cells. Co-labelling of DRG neurons revealed that less than 2 % of PV neurons normally expressed CGRP and no colocalization was seen after injury. Conclusion These experiments clearly show that axotomy does not produce down regulation of PV protein in the DRG. Moreover, this lack of change is not due to a phenotypic switch in PV immunoreactive (ir) neurons, or de novo expression of PV-ir in uninjured neurons after nerve injury. These results further illustrate differences that occur when muscle afferents are injured as compared to cutaneous afferents.
Collapse
Affiliation(s)
- Tom Medici
- Centre for Neuroscience and Trauma, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Newark Street, London, E1 2AT, UK. .,Queens Hospital, Romford, Essex, RM7 0AG, UK.
| | - Peter J Shortland
- School of Science and Health, Western Sydney University, Narellen Road, Campbelltown, NSW, 2560, Australia. .,Centre for Neuroscience and Trauma, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Newark Street, London, E1 2AT, UK.
| |
Collapse
|
22
|
Fukuoka T, Noguchi K. A potential anti-allodynic mechanism of GDNF following L5 spinal nerve ligation; Mitigation of NPY up-regulation in the touch sense pathway. Neuroscience 2015. [PMID: 26215916 DOI: 10.1016/j.neuroscience.2015.07.059] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Intrathecal delivery of glial cell line-derived neurotrophic factor (GDNF) reverses mechanical allodynia after 5th lumbar (L5) spinal nerve ligation (SNL). However, the molecular mechanism behind this process is not fully understood. Following sciatic nerve injury, primary afferent neurons in the injured dorsal root ganglion (DRG) begin to express neuropeptide Y (NPY) that is absent in normal DRG. The aim of the current study was to determine the relationship of this de novo expression of NPY and the anti-allodynic effect of GDNF. Following L5 SNL, 73% of neurons began to express NPY mRNA in the ipsilateral L5 DRG and robust NPY-immunoreactive fibers appeared in the ipsilateral GN where the touch-sense mediating A-fiber primary afferents from the hindpaw terminate. Seven-daylong intrathecal infusion of GDNF at the L5 DRG level, starting on day three when mechanical allodynia had fully developed, reversed once-established these changes. The GN neurons normally expressed NPY Y1 receptor, but not Y2, Y4, or Y5 receptors, and L5 SNL did not change the expression pattern. Bolus intracisternal injection of BIBP3226, a Y1 receptor antagonist, dose-dependently reversed mechanical allodynia. We demonstrated that GDNF reversed once-established mechanical allodynia as well as NPY induction in the touch-sense processing pathway. NPY could facilitate touch-sense processing by Y1 receptor in the gracile nucleus after peripheral nerve injury. GDNF may exert anti-allodynic effects through mitigation of this NPY up-regulation. The effectiveness of delayed treatment further indicates the therapeutic potential of GDNF on neuropathic pain.
Collapse
Affiliation(s)
- T Fukuoka
- Department of Anatomy & Neuroscience, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan; Pain Mechanism Research Group, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan.
| | - K Noguchi
- Department of Anatomy & Neuroscience, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan
| |
Collapse
|
23
|
Shehab S, Anwer M, Galani D, Abdulkarim A, Al-Nuaimi K, Al-Baloushi A, Tariq S, Nagelkerke N, Ljubisavljevic M. Anatomical evidence that the uninjured adjacent L4 nerve plays a significant role in the development of peripheral neuropathic pain after L5 spinal nerve ligation in rats. J Comp Neurol 2015; 523:1731-47. [DOI: 10.1002/cne.23750] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 01/15/2015] [Accepted: 01/18/2015] [Indexed: 12/19/2022]
Affiliation(s)
- Safa Shehab
- Department of Anatomy, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Mehwish Anwer
- Department of Anatomy, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Divya Galani
- Department of Anatomy, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Afaf Abdulkarim
- Department of Anatomy, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Khuloud Al-Nuaimi
- Department of Anatomy, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Abdullah Al-Baloushi
- Department of Anatomy, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Saeed Tariq
- Department of Anatomy, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Nico Nagelkerke
- Department of Community Medicine, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| | - Milos Ljubisavljevic
- Department of Physiology, College of Medicine and Health Sciences; United Arab Emirates University; Al-Ain UAE
| |
Collapse
|
24
|
Su J, Gao T, Shi T, Xiang Q, Xu X, Wiesenfeld-Hallin Z, Hökfelt T, Svensson CI. Phenotypic changes in dorsal root ganglion and spinal cord in the collagen antibody-induced arthritis mouse model. J Comp Neurol 2015; 523:1505-28. [DOI: 10.1002/cne.23749] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 12/26/2014] [Accepted: 01/24/2015] [Indexed: 12/31/2022]
Affiliation(s)
- Jie Su
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm 171 77 Sweden
| | - Tianle Gao
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm 171 77 Sweden
| | - Tiejun Shi
- Department of Neuroscience; Karolinska Institutet; Stockholm 171 77 Sweden
| | - Qiong Xiang
- Department of Neuroscience; Karolinska Institutet; Stockholm 171 77 Sweden
| | - Xiaojun Xu
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm 171 77 Sweden
| | | | - Tomas Hökfelt
- Department of Neuroscience; Karolinska Institutet; Stockholm 171 77 Sweden
| | - Camilla I. Svensson
- Department of Physiology and Pharmacology; Karolinska Institutet; Stockholm 171 77 Sweden
| |
Collapse
|
25
|
Sasaki M, Hashimoto S, Sawa T, Amaya F. Tumor necrosis factor-alpha induces expression of C/EBP-beta in primary afferent neurons following nerve injury. Neuroscience 2014; 279:1-9. [PMID: 25173154 DOI: 10.1016/j.neuroscience.2014.08.032] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2014] [Revised: 07/16/2014] [Accepted: 08/01/2014] [Indexed: 12/28/2022]
Abstract
CCAAT/enhancer binding protein-beta (C/EBP-beta) is a transcription factor that belongs to the C/EBP family. To understand the role of C/EBP-beta in the peripheral nervous system, we investigated the expression of C/EBP-beta in the dorsal root ganglion. C/EBP-beta was weakly detected in nuclei of naive dorsal root ganglion (DRG) neurons. Spinal nerve ligation increased the expression of C/EBP-beta in L4 and L5 DRG neurons. Treatment with anti-TNF-alpha prevented SNL-induced pain hypersensitivity and C/EBP-beta expression in the DRG. Injection of TNF-alpha into the sciatic nerve produced transient pain hypersensitivity and induction of C/EBP-beta expression in the DRG. These results demonstrate that C/EBP-beta is activated in the DRG neurons by a TNF-alpha-dependent manner and might be involved in the activation of primary afferent neurons after nerve injury.
Collapse
Affiliation(s)
- M Sasaki
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - S Hashimoto
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - T Sawa
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - F Amaya
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
| |
Collapse
|
26
|
Gene therapy for neuropathic pain by silencing of TNF-α expression with lentiviral vectors targeting the dorsal root ganglion in mice. PLoS One 2014; 9:e92073. [PMID: 24642694 PMCID: PMC3958473 DOI: 10.1371/journal.pone.0092073] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 02/19/2014] [Indexed: 12/23/2022] Open
Abstract
Neuropathic pain can be a debilitating condition. Many types of drugs that have been used to treat neuropathic pain have only limited efficacy. Recent studies indicate that pro-inflammatory mediators including tumor necrosis factor α (TNF-α) are involved in the pathogenesis of neuropathic pain. In the present study, we engineered a gene therapy strategy to relieve neuropathic pain by silencing TNF-α expression in the dorsal root ganglion (DRG) using lentiviral vectors expressing TNF short hairpin RNA1-4 (LV-TNF-shRNA1-4) in mice. First, based on its efficacy in silencing TNF-α in vitro, we selected shRNA3 to construct LV-TNF-shRNA3 for in vivo study. We used L5 spinal nerve transection (SNT) mice as a neuropathic pain model. These animals were found to display up-regulated mRNA expression of activating transcription factor 3 (ATF3) and neuropeptide Y (NPY), injury markers, and interleukin (IL)-6, an inflammatory cytokine in the ipsilateral L5 DRG. Injection of LV-TNF-shRNA3 onto the proximal transected site suppressed significantly the mRNA levels of ATF3, NPY and IL-6, reduced mechanical allodynia and neuronal cell death of DRG neurons. These results suggest that lentiviral-mediated silencing of TNF-α in DRG relieves neuropathic pain and reduces neuronal cell death, and may constitute a novel therapeutic option for neuropathic pain.
Collapse
|
27
|
Laedermann CJ, Pertin M, Suter MR, Decosterd I. Voltage-gated sodium channel expression in mouse DRG after SNI leads to re-evaluation of projections of injured fibers. Mol Pain 2014; 10:19. [PMID: 24618114 PMCID: PMC4007621 DOI: 10.1186/1744-8069-10-19] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Accepted: 02/28/2014] [Indexed: 12/19/2022] Open
Abstract
Background Dysregulation of voltage-gated sodium channels (Navs) is believed to play a major role in nerve fiber hyperexcitability associated with neuropathic pain. A complete transcriptional characterization of the different isoforms of Navs under normal and pathological conditions had never been performed on mice, despite their widespread use in pain research. Navs mRNA levels in mouse dorsal root ganglia (DRG) were studied in the spared nerve injury (SNI) and spinal nerve ligation (SNL) models of neuropathic pain. In the SNI model, injured and non-injured neurons were intermingled in lumbar DRG, which were pooled to increase the tissue available for experiments. Results A strong downregulation was observed for every Navs isoform expressed except for Nav1.2; even Nav1.3, known to be upregulated in rat neuropathic pain models, was lower in the SNI mouse model. This suggests differences between these two species. In the SNL model, where the cell bodies of injured and non-injured fibers are anatomically separated between different DRG, most Navs were observed to be downregulated in the L5 DRG receiving axotomized fibers. Transcription was then investigated independently in the L3, L4 and L5 DRG in the SNI model, and an important downregulation of many Navs isoforms was observed in the L3 DRG, suggesting the presence of numerous injured neurons there after SNI. Consequently, the proportion of axotomized neurons in the L3, L4 and L5 DRG after SNI was characterized by studying the expression of activating transcription factor 3 (ATF3). Using this marker of nerve injury confirmed that most injured fibers find their cell bodies in the L3 and L4 DRG after SNI in C57BL/6 J mice; this contrasts with their L4 and L5 DRG localization in rats. The spared sural nerve, through which pain hypersensitivity is measured in behavioral studies, mostly projects into the L4 and L5 DRG. Conclusions The complex regulation of Navs, together with the anatomical rostral shift of the DRG harboring injured fibers in C57BL/6 J mice, emphasize that caution is necessary and preliminary anatomical experiments should be carried out for gene and protein expression studies after SNI in mouse strains.
Collapse
Affiliation(s)
- Cédric J Laedermann
- Pain Center, Department of Anesthesiology, University Hospital Center and University of Lausanne, Lausanne 1011, Switzerland.
| | | | | | | |
Collapse
|
28
|
Amaya F, Izumi Y, Matsuda M, Sasaki M. Tissue injury and related mediators of pain exacerbation. Curr Neuropharmacol 2014; 11:592-7. [PMID: 24396335 PMCID: PMC3849785 DOI: 10.2174/1570159x11311060003] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Revised: 06/13/2013] [Accepted: 07/12/2013] [Indexed: 01/03/2023] Open
Abstract
Tissue injury and inflammation result in release of various mediators that promote ongoing pain or pain hypersensitivity against mechanical, thermal and chemical stimuli. Pro-nociceptive mediators activate primary afferent neurons directly or indirectly to enhance nociceptive signal transmission to the central nervous system. Excitation of primary afferents by peripherally originating mediators, so-called “peripheral sensitization”, is a hallmark of tissue injury-related pain. Many kinds of pro-nociceptive mediators, including ATP, glutamate, kinins, cytokines and tropic factors, synthesized at the damaged tissue, contribute to the development of peripheral sensitization. In the present review we will discuss the molecular mechanisms of peripheral sensitization following tissue injury.
Collapse
Affiliation(s)
- Fumimasa Amaya
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kajiicho 465, Kamigyo-Ku, Kyoto 602-8566, Japan
| | - Yuta Izumi
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kajiicho 465, Kamigyo-Ku, Kyoto 602-8566, Japan
| | - Megumi Matsuda
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kajiicho 465, Kamigyo-Ku, Kyoto 602-8566, Japan
| | - Mika Sasaki
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kajiicho 465, Kamigyo-Ku, Kyoto 602-8566, Japan
| |
Collapse
|
29
|
Shehab SADS. Fifth lumbar spinal nerve injury causes neurochemical changes in corresponding as well as adjacent spinal segments: a possible mechanism underlying neuropathic pain. J Chem Neuroanat 2014; 55:38-50. [PMID: 24394408 DOI: 10.1016/j.jchemneu.2013.12.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Revised: 12/23/2013] [Accepted: 12/23/2013] [Indexed: 01/19/2023]
Abstract
Previous investigations of the anatomical basis of the neuropathic-like manifestations in the spinal nerve ligation animal model have shown that the central terminations of the unmyelinated primary afferents of L5 spinal nerve are not restricted to the corresponding L5 spinal segment, and rather extend to two spinal segments rostrally and one segment caudally where they intermingle with primary afferents of the adjacent L4 spinal nerve. The aim of the present study was to investigate the neurochemical changes in the dorsal horn of the spinal cord and DRGs after L5 nerve injury in rats. In the first experiment, the right L5 nerve was ligated and sectioned for 14 days, and isolectin B4 (IB4, a tracer for unmyelinated primary afferents) was injected into the left L5 nerve. The results showed that the vasoactive intestinal peptide (VIP) was up-regulated in laminae I-II of L3-L6 spinal segments on the right side in exactly the same areas where IB4 labelled terminals were revealed on the left side. In the second experiment, L5 was ligated and sectioned and the spinal cord and DRGs were stained immunocytochemically with antibodies raised against various peptides known to be involved in pain transmission and hyperalgesia. The results showed that L5 nerve lesion caused down-regulation of substance P, calcitonin-gene related peptide and IB4 binding and up-regulation of neuropeptide Y and neurokinin-1 receptor in the dorsal horn of L4 and L5 spinal segments. Similar neurochemical changes were observed only in the corresponding L5 DRG with minimal effects observed in L3, L4 and L6 DRGs. Although, L5 nerve injury caused an up-regulation in NPY, no change in SP and CGRP immunoreactivity was observed in ipsilateral garcile nucleus. These neuroplastic changes in the dorsal horn of the spinal cord, in the adjacent uninjured territories of the central terminations of the adjacent uninjured nerves, might explain the mechanism of hyperalgesia after peripheral nerve injury.
Collapse
Affiliation(s)
- Safa Al-Deen Saudi Shehab
- Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, PO BOX 16777, United Arab Emirates.
| |
Collapse
|
30
|
Sakai A, Saitow F, Miyake N, Miyake K, Shimada T, Suzuki H. miR-7a alleviates the maintenance of neuropathic pain through regulation of neuronal excitability. ACTA ACUST UNITED AC 2013; 136:2738-50. [PMID: 23861446 DOI: 10.1093/brain/awt191] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Neuronal damage in the somatosensory system causes intractable chronic neuropathic pain. Plastic changes in sensory neuron excitability are considered the cellular basis of persistent pain. Non-coding microRNAs modulate specific gene translation to impact on diverse cellular functions and their dysregulation causes various diseases. However, their significance in adult neuronal functions and disorders is still poorly understood. Here, we show that miR-7a is a key functional RNA sustaining the late phase of neuropathic pain through regulation of neuronal excitability in rats. In the late phase of neuropathic pain, microarray analysis identified miR-7a as the most robustly decreased microRNA in the injured dorsal root ganglion. Moreover, local induction of miR-7a, using an adeno-associated virus vector, in sensory neurons of injured dorsal root ganglion, suppressed established neuropathic pain. In contrast, miR-7a overexpression had no effect on acute physiological or inflammatory pain. Furthermore, miR-7a downregulation was sufficient to cause pain-related behaviours in intact rats. miR-7a targeted the β2 subunit of the voltage-gated sodium channel, and decreased miR-7a associated with neuropathic pain caused increased β2 subunit protein expression, independent of messenger RNA levels. Consistently, miR-7a overexpression in primary sensory neurons of injured dorsal root ganglion suppressed increased β2 subunit expression and normalized long-lasting hyperexcitability of nociceptive neurons. These findings demonstrate miR-7a downregulation is causally involved in maintenance of neuropathic pain through regulation of neuronal excitability, and miR-7a replenishment offers a novel therapeutic strategy specific for chronic neuropathic pain.
Collapse
Affiliation(s)
- Atsushi Sakai
- Department of Pharmacology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8602, Japan
| | | | | | | | | | | |
Collapse
|
31
|
Sakai A, Suzuki H. Nerve injury-induced upregulation of miR-21 in the primary sensory neurons contributes to neuropathic pain in rats. Biochem Biophys Res Commun 2013; 435:176-81. [DOI: 10.1016/j.bbrc.2013.04.089] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Accepted: 04/21/2013] [Indexed: 01/17/2023]
|
32
|
Hagenacker T, Schäfer N, Büsselberg D, Schäfers M. Analgesic ineffectiveness of lacosamide after spinal nerve ligation and its sodium channel activity in injured neurons. Eur J Pain 2012; 17:881-92. [DOI: 10.1002/j.1532-2149.2012.00260.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/12/2012] [Indexed: 11/10/2022]
Affiliation(s)
- T. Hagenacker
- Department of Neurology; University Hospital Essen; Germany
| | - N. Schäfer
- Department of Neurology; University Hospital Essen; Germany
| | - D. Büsselberg
- Weill Cornell Medical College in Qatar; Qatar Foundation-Education City; Doha; Qatar
| | - M. Schäfers
- Department of Neurology; University Hospital Essen; Germany
| |
Collapse
|
33
|
Cachemaille M, Laedermann CJ, Pertin M, Abriel H, Gosselin RD, Decosterd I. Neuronal expression of the ubiquitin ligase Nedd4-2 in rat dorsal root ganglia: modulation in the spared nerve injury model of neuropathic pain. Neuroscience 2012; 227:370-80. [PMID: 23022218 DOI: 10.1016/j.neuroscience.2012.09.044] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Revised: 09/13/2012] [Accepted: 09/19/2012] [Indexed: 10/27/2022]
Abstract
Neuronal hyperexcitability following peripheral nerve lesions may stem from altered activity of voltage-gated sodium channels (VGSCs), which gives rise to allodynia or hyperalgesia. In vitro, the ubiquitin ligase Nedd4-2 is a negative regulator of VGSC α-subunits (Na(v)), in particular Na(v)1.7, a key actor in nociceptor excitability. We therefore studied Nedd4-2 in rat nociceptors, its co-expression with Na(v)1.7 and Na(v)1.8, and its regulation in pathology. Adult rats were submitted to the spared nerve injury (SNI) model of neuropathic pain or injected with complete Freund's adjuvant (CFA), a model of inflammatory pain. L4 dorsal root ganglia (DRG) were analyzed in sham-operated animals, seven days after SNI and 48 h after CFA with immunofluorescence and Western blot. We observed Nedd4-2 expression in almost 50% of DRG neurons, mostly small and medium-sized. A preponderant localization is found in the non-peptidergic sub-population. Additionally, 55.7 ± 2.7% and 55.0 ± 3.6% of Nedd4-2-positive cells are co-labeled with Na(v)1.7 and Na(v)1.8 respectively. SNI significantly decreases the proportion of Nedd4-2-positive neurons from 45.9 ± 1.9% to 33.5 ± 0.7% (p<0.01) and the total Nedd4-2 protein to 44% ± 0.13% of its basal level (p<0.01, n=4 animals in each group, mean ± SEM). In contrast, no change in Nedd4-2 was found after peripheral inflammation induced by CFA. These results indicate that Nedd4-2 is present in nociceptive neurons, is downregulated after peripheral nerve injury, and might therefore contribute to the dysregulation of Na(v)s involved in the hyperexcitability associated with peripheral nerve injuries.
Collapse
Affiliation(s)
- M Cachemaille
- Pain Center, Department of Anesthesiology, University Hospital Center (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.
| | | | | | | | | | | |
Collapse
|
34
|
Abstract
Neuropathic pain is a common cause of pain after nerve injury, but its molecular basis is poorly understood. In a post-gene chip microarray effort to identify new target genes contributing to neuropathic pain development, we report here the characterization of a novel neuropathic pain contributor, thrombospondin-4 (TSP4), using a neuropathic pain model of spinal nerve ligation injury. TSP4 is mainly expressed in astrocytes and significantly upregulated in the injury side of dorsal spinal cord that correlates with the development of neuropathic pain states. TSP4 blockade by intrathecal antibodies, antisense oligodeoxynucleotides, or inactivation of the TSP4 gene reverses or prevents behavioral hypersensitivities. Intrathecal injection of TSP4 protein into naive rats is sufficient to enhance the frequency of EPSCs in spinal dorsal horn neurons, suggesting an increased excitatory presynaptic input, and to cause similar behavioral hypersensitivities. Together, these findings support that injury-induced spinal TSP4 may contribute to spinal presynaptic hypersensitivity and neuropathic pain states. Development of TSP4 antagonists has the therapeutic potential for target-specific neuropathic pain management.
Collapse
|
35
|
Hsieh YL, Chiang H, Lue JH, Hsieh ST. P2X3-mediated peripheral sensitization of neuropathic pain in resiniferatoxin-induced neuropathy. Exp Neurol 2012; 235:316-25. [PMID: 22391132 DOI: 10.1016/j.expneurol.2012.02.013] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2011] [Revised: 02/10/2012] [Accepted: 02/20/2012] [Indexed: 11/29/2022]
Abstract
Patients suffering from sensory neuropathy due to skin denervation frequently have paradoxical manifestations of reduced nociception and neuropathic pain. However, there is a lack of satisfactory animal models to investigate these phenomena and underlying mechanisms. We developed a mouse system of neuropathy induced by resiniferatoxin (RTX), a capsaicin analog, and examined the functional significance of P2X3 receptor in neuropathic pain. From day 7 of RTX neuropathy, mice displayed mechanical allodynia (p<0.0001) and thermal hypoalgesia (p<0.0001). After RTX treatment, dorsal root ganglion (DRG) neurons of the peripherin type were depleted (p=0.012), while neurofilament (+) DRG neurons were not affected (p=0.62). In addition, RTX caused a shift in neuronal profiles of DRG: (1) increased in P2X3 receptor (p=0.0002) and ATF3 (p=0.0006) but (2) reduced TRPV1 (p=0.036) and CGRP (p=0.015). The number of P2X3(+)/ATF3(+) neurons was linearly correlated with mechanical thresholds (p=0.0017). The peripheral expression of P2X3 receptor in dermal nerves was accordingly increased (p=0.016), and an intraplantar injection of the P2X3 antagonists, A-317491 and TNP-ATP, relieved mechanical allodynia in a dose-dependent manner. In conclusion, RTX-induced sensory neuropathy with upregulation of P2X3 receptor for peripheral sensitization of mechanical allodynia, which provides a new therapeutic target for neuropathic pain after skin denervation.
Collapse
Affiliation(s)
- Yu-Lin Hsieh
- Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
| | | | | | | |
Collapse
|
36
|
Tetrodotoxin (TTX) as a therapeutic agent for pain. Mar Drugs 2012; 10:281-305. [PMID: 22412801 PMCID: PMC3296997 DOI: 10.3390/md10020281] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2011] [Revised: 01/19/2012] [Accepted: 01/19/2012] [Indexed: 12/19/2022] Open
Abstract
Tetrodotoxin (TTX) is a potent neurotoxin that blocks voltage-gated sodium channels (VGSCs). VGSCs play a critical role in neuronal function under both physiological and pathological conditions. TTX has been extensively used to functionally characterize VGSCs, which can be classified as TTX-sensitive or TTX-resistant channels according to their sensitivity to this toxin. Alterations in the expression and/or function of some specific TTX-sensitive VGSCs have been implicated in a number of chronic pain conditions. The administration of TTX at doses below those that interfere with the generation and conduction of action potentials in normal (non-injured) nerves has been used in humans and experimental animals under different pain conditions. These data indicate a role for TTX as a potential therapeutic agent for pain. This review focuses on the preclinical and clinical evidence supporting a potential analgesic role for TTX. In addition, the contribution of specific TTX-sensitive VGSCs to pain is reviewed.
Collapse
|
37
|
Todd AJ. How to recognise collateral damage in partial nerve injury models of neuropathic pain. Pain 2011; 153:11-12. [PMID: 22079327 DOI: 10.1016/j.pain.2011.10.031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Revised: 10/12/2011] [Accepted: 10/24/2011] [Indexed: 11/28/2022]
Affiliation(s)
- Andrew J Todd
- Institute of Neuroscience and Psychology, University of Glasgow, Glasgow G12 8QQ, UK
| |
Collapse
|