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Scheid S, Goebel U, Ulbrich F. Neuroprotection Is in the Air-Inhaled Gases on Their Way to the Neurons. Cells 2023; 12:2480. [PMID: 37887324 PMCID: PMC10605176 DOI: 10.3390/cells12202480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 09/29/2023] [Accepted: 10/13/2023] [Indexed: 10/28/2023] Open
Abstract
Cerebral injury is a leading cause of long-term disability and mortality. Common causes include major cardiovascular events, such as cardiac arrest, ischemic stroke, and subarachnoid hemorrhage, traumatic brain injury, and neurodegenerative as well as neuroinflammatory disorders. Despite improvements in pharmacological and interventional treatment options, due to the brain's limited regeneration potential, survival is often associated with the impairment of crucial functions that lead to occupational inability and enormous economic burden. For decades, researchers have therefore been investigating adjuvant therapeutic options to alleviate neuronal cell death. Although promising in preclinical studies, a huge variety of drugs thought to provide neuroprotective effects failed in clinical trials. However, utilizing medical gases, noble gases, and gaseous molecules as supportive treatment options may offer new perspectives for patients suffering neuronal damage. This review provides an overview of current research, potentials and mechanisms of these substances as a promising therapeutic alternative for the treatment of cerebral injury.
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Affiliation(s)
- Stefanie Scheid
- Department of Anesthesiology and Critical Care, Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany;
| | - Ulrich Goebel
- Department of Anesthesiology and Critical Care Medicine, St. Franziskus-Hospital, 48145 Muenster, Germany;
| | - Felix Ulbrich
- Department of Anesthesiology and Critical Care, Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany;
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2
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Szallasi A. "ThermoTRP" Channel Expression in Cancers: Implications for Diagnosis and Prognosis (Practical Approach by a Pathologist). Int J Mol Sci 2023; 24:9098. [PMID: 37240443 PMCID: PMC10219044 DOI: 10.3390/ijms24109098] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 05/16/2023] [Accepted: 05/18/2023] [Indexed: 05/28/2023] Open
Abstract
Temperature-sensitive transient receptor potential (TRP) channels (so-called "thermoTRPs") are multifunctional signaling molecules with important roles in cell growth and differentiation. Several "thermoTRP" channels show altered expression in cancers, though it is unclear if this is a cause or consequence of the disease. Regardless of the underlying pathology, this altered expression may potentially be used for cancer diagnosis and prognostication. "ThermoTRP" expression may distinguish between benign and malignant lesions. For example, TRPV1 is expressed in benign gastric mucosa, but is absent in gastric adenocarcinoma. TRPV1 is also expressed both in normal urothelia and non-invasive papillary urothelial carcinoma, but no TRPV1 expression has been seen in invasive urothelial carcinoma. "ThermoTRP" expression can also be used to predict clinical outcomes. For instance, in prostate cancer, TRPM8 expression predicts aggressive behavior with early metastatic disease. Furthermore, TRPV1 expression can dissect a subset of pulmonary adenocarcinoma patients with bad prognosis and resistance to a number of commonly used chemotherapeutic agents. This review will explore the current state of this rapidly evolving field with special emphasis on immunostains that can already be added to the armoire of diagnostic pathologists.
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Affiliation(s)
- Arpad Szallasi
- Department of Pathology and Experimental Cancer Research, Semmelweis University, 1085 Budapest, Hungary
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3
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Szallasi A. The Vanilloid (Capsaicin) Receptor TRPV1 in Blood Pressure Regulation: A Novel Therapeutic Target in Hypertension? Int J Mol Sci 2023; 24:8769. [PMID: 37240118 PMCID: PMC10217837 DOI: 10.3390/ijms24108769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 05/04/2023] [Accepted: 05/07/2023] [Indexed: 05/28/2023] Open
Abstract
Today's sedentary lifestyle with excess food and little exercise increases the number of people with hypertension, a major risk factor for stroke. New knowledge of treatments in this field is of utmost importance. In animal experiments, the activation by capsaicin of TRPV1-expressing sensory afferents evokes a drop in blood pressure by triggering the Bezold-Jarisch reflex. In hypertensive rats, capsaicin reduces blood pressure. Conversely, genetic ablation of the TRPV1 receptor results in elevated nocturnal (but not diurnal) blood pressure. These observations imply a therapeutic potential for TRPV1 activation in hypertensive patients. Indeed, in a major epidemiological study involving 9273 volunteers, dietary capsaicin was found to lower the risk for hypertension. New research indicates that the mechanism of action of capsaicin on blood pressure regulation is far more complex than previously thought. In addition to the well-recognized role of capsaicin-sensitive afferents in blood pressure regulation, TRPV1 seems to be expressed both in endothelial cells and vascular smooth muscle. This review aims to evaluate the therapeutic potential of TRPV1-targeting drugs in hypertensive patients.
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Affiliation(s)
- Arpad Szallasi
- Department of Pathology and Experimental Cancer Research, Semmelweis University, 1085 Budapest, Hungary
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4
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Pintér E, Helyes Z, Szőke É, Bölcskei K, Kecskés A, Pethő G. The triple function of the capsaicin-sensitive sensory neurons: In memoriam János Szolcsányi. Temperature (Austin) 2022; 10:13-34. [PMID: 38059854 PMCID: PMC10177685 DOI: 10.1080/23328940.2022.2147388] [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: 08/31/2022] [Revised: 11/08/2022] [Accepted: 11/08/2022] [Indexed: 11/23/2022] Open
Abstract
This paper is dedicated to the memory of János Szolcsányi (1938-2018), an outstanding Hungarian scientist. Among analgesics that act on pain receptors, he identified capsaicin as a selective lead molecule. He studied the application of capsaicin and revealed several physiological (pain, thermoregulation) and pathophysiological (inflammation, gastric ulcer) mechanisms. He discovered a new neuroregulatory system without sensory efferent reflex and investigated its pharmacology. The authors of this review are his former Ph.D. students who carried out their doctoral work in Szolcsányi's laboratory between 1985 and 2010 and report on the scientific results obtained under his guidance. His research group provided evidence for the triple function of the peptidergic capsaicin-sensitive sensory neurons including classical afferent function, local efferent responses, and remote, hormone-like anti-inflammatory, and antinociceptive actions. They also proposed somatostatin receptor type 4 as a promising drug target for the treatment of pain and inflammation. They revealed that neonatal capsaicin treatment caused no acute neuronal death but instead long-lasting selective ultrastructural and functional changes in B-type sensory neurons, similar to adult treatment. They described that lipid raft disruption diminished the agonist-induced channel opening of the TRPV1, TRPA1, and TRPM8 receptors in native sensory neurons. Szolcsányi's group has developed new devices for noxious heat threshold measurement: an increasing temperature hot plate and water bath. This novel approach proved suitable for assessing the thermal antinociceptive effects of analgesics as well as for analyzing peripheral mechanisms of thermonociception.
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Affiliation(s)
- Erika Pintér
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Szigeti str. 12, H-7624, Pécs, Hungary
- National Laboratory for Drug Research and Development, Magyar tudósok krt. 2. H-1117Budapest, Hungary
- Eötvös Lorand Research Network, Chronic Pain Research Group, University of Pécs, H7624, Pécs, Hungary
| | - Zsuzsanna Helyes
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Szigeti str. 12, H-7624, Pécs, Hungary
- National Laboratory for Drug Research and Development, Magyar tudósok krt. 2. H-1117Budapest, Hungary
- Eötvös Lorand Research Network, Chronic Pain Research Group, University of Pécs, H7624, Pécs, Hungary
| | - Éva Szőke
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Szigeti str. 12, H-7624, Pécs, Hungary
- National Laboratory for Drug Research and Development, Magyar tudósok krt. 2. H-1117Budapest, Hungary
- Eötvös Lorand Research Network, Chronic Pain Research Group, University of Pécs, H7624, Pécs, Hungary
| | - Kata Bölcskei
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Szigeti str. 12, H-7624, Pécs, Hungary
| | - Angéla Kecskés
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Szigeti str. 12, H-7624, Pécs, Hungary
| | - Gábor Pethő
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Szigeti str. 12, H-7624, Pécs, Hungary
- Department of Pharmacology, Faculty of Pharmacy, University of Pécs, Rókus Str. 2, H-7624 , Pécs, Hungary
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5
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Visual Disfunction due to the Selective Effect of Glutamate Agonists on Retinal Cells. Int J Mol Sci 2021; 22:ijms22126245. [PMID: 34200611 PMCID: PMC8230349 DOI: 10.3390/ijms22126245] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/25/2021] [Accepted: 05/30/2021] [Indexed: 02/07/2023] Open
Abstract
One of the causes of nervous system degeneration is an excess of glutamate released upon several diseases. Glutamate analogs, like N-methyl-DL-aspartate (NMDA) and kainic acid (KA), have been shown to induce experimental retinal neurotoxicity. Previous results have shown that NMDA/KA neurotoxicity induces significant changes in the full field electroretinogram response, a thinning on the inner retinal layers, and retinal ganglion cell death. However, not all types of retinal neurons experience the same degree of injury in response to the excitotoxic stimulus. The goal of the present work is to address the effect of intraocular injection of different doses of NMDA/KA on the structure and function of several types of retinal cells and their functionality. To globally analyze the effect of glutamate receptor activation in the retina after the intraocular injection of excitotoxic agents, a combination of histological, electrophysiological, and functional tools has been employed to assess the changes in the retinal structure and function. Retinal excitotoxicity caused by the intraocular injection of a mixture of NMDA/KA causes a harmful effect characterized by a great loss of bipolar, amacrine, and retinal ganglion cells, as well as the degeneration of the inner retina. This process leads to a loss of retinal cell functionality characterized by an impairment of light sensitivity and visual acuity, with a strong effect on the retinal OFF pathway. The structural and functional injury suffered by the retina suggests the importance of the glutamate receptors expressed by different types of retinal cells. The effect of glutamate agonists on the OFF pathway represents one of the main findings of the study, as the evaluation of the retinal lesions caused by excitotoxicity could be specifically explored using tests that evaluate the OFF pathway.
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da Silva Fiorin F, do Espírito Santo CC, do Nascimento RS, Cassol G, Plácido E, Santos ARS, Marques JLB, Brocardo PS, Fighera MR, Royes LFF. Capsaicin-sensitive fibers mediate periorbital allodynia and activation of inflammatory cells after traumatic brain injury in rats: Involvement of TRPV1 channels in post-traumatic headache. Neuropharmacology 2020; 176:108215. [PMID: 32574651 DOI: 10.1016/j.neuropharm.2020.108215] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 05/30/2020] [Accepted: 06/15/2020] [Indexed: 12/26/2022]
Abstract
Post-traumatic headache (PTH) is a condition that frequently affects individuals after traumatic brain injury (TBI). Inflammation is one of the major causes of this disability. However, little is known about the trigger for, and endurance of, this painful process. Thus, the involvement of fibers containing the transient receptor potential vanilloid 1 (TRPV1) channels on the PTH and inflammation after TBI through neonatal treatment with capsaicin are investigated. Fluid percussion injury (FPI) in adult male Wistar rats caused periorbital allodynia in one, three and seven days after injury, and the neonatal treatment reversed the painful sensation in seven days. The lack of TRPV1 channels reduced the activation of macrophages and glial cells induced by TBI in the trigeminal system, which were characterized by glial fibrillary acidic protein (GFAP) and ionized calcium binding adapter molecule-1 (IBA-1) immune content in the ipsilateral trigeminal ganglion, brainstem, and perilesional cortex. Immunofluorescence analyses of the ipsilateral Sp5C nucleus demonstrated a hypertrophic astrocytes profile after TBI which was reduced with treatment. Moreover, effects of succinate sumatriptan (SUMA - 1 mg/kg), TRPV1 selective antagonist capsazepine (CPZ - 2 mg/kg), and TRP non-selective antagonist ruthenium red (RR - 3 mg/kg) were evaluated. Although all mentioned drugs reduced the painful sensation, SUMA and CPZ demonstrated a stronger effect compared to the RR treatment, reinforcing the involvement of TRPV1 channels in periorbital allodynia after TBI. Hence, this report suggests that TRPV1-containing fibers and TRPV1 channels are able to induce inflammation of the trigeminal system and maintain the painful sensation after TBI.
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Affiliation(s)
- Fernando da Silva Fiorin
- Programa de Pós-Graduação em Neurociências, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil; Laboratório de Neurobiologia da Dor e Inflamação, Departamento de Ciências Fisiológicas, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil; Laboratório de Bioquímica do Exercício, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil.
| | - Caroline Cunha do Espírito Santo
- Programa de Pós-Graduação em Neurociências, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil; Laboratório de Neurobiologia da Dor e Inflamação, Departamento de Ciências Fisiológicas, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Raphael Santos do Nascimento
- Instituto de Engenharia Biomédica, Departamento de Engenharia Elétrica e Eletrônica, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Gustavo Cassol
- Laboratório de Bioquímica do Exercício, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Evelini Plácido
- Programa de Pós-Graduação em Neurociências, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil; Laboratório de Neuroplasticidade, Departamento de Ciências Morfológicas, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Adair Roberto Soares Santos
- Programa de Pós-Graduação em Neurociências, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil; Laboratório de Neurobiologia da Dor e Inflamação, Departamento de Ciências Fisiológicas, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Jefferson Luiz Brum Marques
- Instituto de Engenharia Biomédica, Departamento de Engenharia Elétrica e Eletrônica, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Patricia S Brocardo
- Programa de Pós-Graduação em Neurociências, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil; Laboratório de Neuroplasticidade, Departamento de Ciências Morfológicas, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Michele Rechia Fighera
- Programa de Pós-Graduação em Neurociências, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil; Laboratório de Bioquímica do Exercício, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Luiz Fernando Freire Royes
- Programa de Pós-Graduação em Neurociências, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil; Laboratório de Bioquímica do Exercício, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
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7
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Spinal cord injury: pathophysiology, treatment strategies, associated challenges, and future implications. Cell Tissue Res 2019; 377:125-151. [PMID: 31065801 DOI: 10.1007/s00441-019-03039-1] [Citation(s) in RCA: 103] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 04/01/2019] [Indexed: 12/16/2022]
Abstract
Axonal regeneration and formation of tripartite (axo-glial) junctions at damaged sites is a prerequisite for early repair of injured spinal cord. Transplantation of stem cells at such sites of damage which can generate both neuronal and glial population has gained impact in terms of recuperation upon infliction with spinal cord injury. In spite of the fact that a copious number of pre-clinical studies using different stem/progenitor cells have shown promising results at acute and subacute stages, at the chronic stages of injury their recovery rates have shown a drastic decline. Therefore, developing novel therapeutic strategies are the need of the hour in order to assuage secondary morbidity and effectuate improvement of the spinal cord injury (SCI)-afflicted patients' quality of life. The present review aims at providing an overview of the current treatment strategies and also gives an insight into the potential cell-based therapies for the treatment of SCI.
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8
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Lee RHC, Lee MHH, Wu CYC, Couto e Silva A, Possoit HE, Hsieh TH, Minagar A, Lin HW. Cerebral ischemia and neuroregeneration. Neural Regen Res 2018; 13:373-385. [PMID: 29623912 PMCID: PMC5900490 DOI: 10.4103/1673-5374.228711] [Citation(s) in RCA: 119] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/01/2018] [Indexed: 12/11/2022] Open
Abstract
Cerebral ischemia is one of the leading causes of morbidity and mortality worldwide. Although stroke (a form of cerebral ischemia)-related costs are expected to reach 240.67 billion dollars by 2030, options for treatment against cerebral ischemia/stroke are limited. All therapies except anti-thrombolytics (i.e., tissue plasminogen activator) and hypothermia have failed to reduce neuronal injury, neurological deficits, and mortality rates following cerebral ischemia, which suggests that development of novel therapies against stroke/cerebral ischemia are urgently needed. Here, we discuss the possible mechanism(s) underlying cerebral ischemia-induced brain injury, as well as current and future novel therapies (i.e., growth factors, nicotinamide adenine dinucleotide, melatonin, resveratrol, protein kinase C isozymes, pifithrin, hypothermia, fatty acids, sympathoplegic drugs, and stem cells) as it relates to cerebral ischemia.
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Affiliation(s)
- Reggie H. C. Lee
- Department of Neurology, Louisiana State University Health Science Center, Shreveport, LA, USA
- Center for Brain Health, Louisiana State University Health Science Center, Shreveport, LA, USA
| | - Michelle H. H. Lee
- Institute of Cellular and System Medicine, National Health Research Institutes, Zhunan, Taiwan, China
| | - Celeste Y. C. Wu
- Department of Neurology, Louisiana State University Health Science Center, Shreveport, LA, USA
- Center for Brain Health, Louisiana State University Health Science Center, Shreveport, LA, USA
| | - Alexandre Couto e Silva
- Department of Cellular Biology and Anatomy, Louisiana State University Health Science Center, Shreveport, LA, USA
| | - Harlee E. Possoit
- Department of Neurology, Louisiana State University Health Science Center, Shreveport, LA, USA
- Center for Brain Health, Louisiana State University Health Science Center, Shreveport, LA, USA
| | - Tsung-Han Hsieh
- Department of Neurology, Louisiana State University Health Science Center, Shreveport, LA, USA
- Center for Brain Health, Louisiana State University Health Science Center, Shreveport, LA, USA
| | - Alireza Minagar
- Department of Neurology, Louisiana State University Health Science Center, Shreveport, LA, USA
| | - Hung Wen Lin
- Department of Neurology, Louisiana State University Health Science Center, Shreveport, LA, USA
- Center for Brain Health, Louisiana State University Health Science Center, Shreveport, LA, USA
- Department of Cellular Biology and Anatomy, Louisiana State University Health Science Center, Shreveport, LA, USA
- Cardiovascular and Metabolomics Research Center, Hualien Tzu Chi Hospital, Hualien, Taiwan, China
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9
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Krishnatreyya H, Hazarika H, Saha A, Chattopadhyay P. Capsaicin, the primary constituent of pepper sprays and its pharmacological effects on mammalian ocular tissues. Eur J Pharmacol 2018; 819:114-121. [DOI: 10.1016/j.ejphar.2017.11.042] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 11/20/2017] [Accepted: 11/24/2017] [Indexed: 01/07/2023]
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10
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Patowary P, Pathak MP, Zaman K, Raju PS, Chattopadhyay P. Research progress of capsaicin responses to various pharmacological challenges. Biomed Pharmacother 2017; 96:1501-1512. [PMID: 29198921 DOI: 10.1016/j.biopha.2017.11.124] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/06/2017] [Accepted: 11/27/2017] [Indexed: 02/07/2023] Open
Abstract
Capsaicin, a well known vanilloid, has shown evidence of an ample variety of biological effects which make it the target of extensive research ever since its identification. In spite of the fact that capsaicin causes health hazards in quite a few ways, yet, the verity cannot be ignored that capsaicin has several therapeutic implications. In patients with hypersensitive bladders, vesical instillation of 1 mM capsaicin markedly improved urinary frequency and urge incontinence. Again, administration of capsaicin favors an augmentation in lipid mobilization and a decrease in adipose tissue mass. Topical capsaicin cream as well decreases postsurgical neuropathic pain and is preferred by patients over a placebo among other therapies. Several in vitro studies have revealed that capsaicin results in growth arrest in some transformed cell lines. Furthermore, capsaicin has been proven to be an undeniably exciting molecule and remains a valuable drug for alleviating pain and itch. It has been recognized that capsaicinoids are the most potential agonists of capsaicin receptor (TRPV1). However, vanilloids could exert the beneficial effects not only through the receptor-dependent pathway but also through the receptor-independent one. The involvement of serotonin, neuropeptide Substance P and somatostatin in the pharmacological actions of capsaicin has been expansively investigated. Better understanding of the established TRPV1 receptor mechanism as well as exploring other possible receptor mechanism may publicize other new clinical efficacies of capsaicin. Further, clinical studies are required in several of these conditions to establish the efficacy of capsaicin.
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Affiliation(s)
- Pompy Patowary
- Division of Pharmaceutical Technology, Defence Research Laboratory, Tezpur, 784 001, Assam, India; Department of Pharmaceutical Sciences, Dibrugarh University, Dibrugarh, 786 004, Assam, India
| | - Manash Pratim Pathak
- Division of Pharmaceutical Technology, Defence Research Laboratory, Tezpur, 784 001, Assam, India; Department of Pharmaceutical Sciences, Dibrugarh University, Dibrugarh, 786 004, Assam, India
| | - Kamaruz Zaman
- Department of Pharmaceutical Sciences, Dibrugarh University, Dibrugarh, 786 004, Assam, India
| | - P S Raju
- Division of Pharmaceutical Technology, Defence Research Laboratory, Tezpur, 784 001, Assam, India
| | - Pronobesh Chattopadhyay
- Division of Pharmaceutical Technology, Defence Research Laboratory, Tezpur, 784 001, Assam, India.
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11
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Kim Y, Davidson JO, Green CR, Nicholson LFB, O'Carroll SJ, Zhang J. Connexins and Pannexins in cerebral ischemia. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1860:224-236. [PMID: 28347700 DOI: 10.1016/j.bbamem.2017.03.018] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 02/24/2017] [Accepted: 03/22/2017] [Indexed: 12/12/2022]
Abstract
A common cause of mortality and long-term adult disability, cerebral ischemia or brain ischemia imposes a significant health and financial burden on communities worldwide. Cerebral ischemia is a condition that arises from a sudden loss of blood flow and consequent failure to meet the high metabolic demands of the brain. The lack of blood flow initiates a sequelae of cell death mechanisms, including the activation of the inflammatory pathway, which can ultimately result in irreversible brain tissue damage. In particular, Connexins and Pannexins are non-selective channels with a large pore that have shown to play time-dependent roles in the perpetuation of ischaemic injury. This review highlights the roles of Connexin and Pannexin channels in cell death mechanisms as a promising therapeutic target in cerebral ischemia, and in particular connexin hemichannels which may contribute most of the ATP release as a result of ischemia as well as during reperfusion. This article is part of a Special Issue entitled: Gap Junction Proteins edited by Jean Claude Herve.
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Affiliation(s)
- Yeri Kim
- Department of Ophthalmology, Faculty of Medical and Health Sciences, University of Auckland
| | - Joanne O Davidson
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland
| | - Colin R Green
- Department of Ophthalmology, Faculty of Medical and Health Sciences, University of Auckland
| | - Louise F B Nicholson
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland
| | - Simon J O'Carroll
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland
| | - Jie Zhang
- Department of Ophthalmology, Faculty of Medical and Health Sciences, University of Auckland.
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12
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Yan Y, Shen FY, Agresti M, Zhang LL, Matloub HS, LoGiudice JA, Havlik R, Li J, Gu YD, Yan JG. Best time window for the use of calcium-modulating agents to improve functional recovery in injured peripheral nerves-An experiment in rats. J Neurosci Res 2017; 95:1786-1795. [PMID: 28052373 DOI: 10.1002/jnr.24009] [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: 08/17/2015] [Revised: 11/23/2016] [Accepted: 11/30/2016] [Indexed: 11/08/2022]
Abstract
Peripheral nerve injury can have a devastating effect on daily life. Calcium concentrations in nerve fibers drastically increase after nerve injury, and this activates downstream processes leading to neuron death. Our previous studies showed that calcium-modulating agents decrease calcium accumulation, which aids in regeneration of injured peripheral nerves; however, the optimal therapeutic window for this application has not yet been identified. In this study, we show that calcium clearance after nerve injury is positively correlated with functional recovery in rats suffering from a crushed sciatic nerve injury. After the nerve injury, calcium accumulation increased. Peak volume is from 2 to 8 weeks post injury; calcium accumulation then gradually decreased over the following 24-week period. The compound muscle action potential (CMAP) measurement from the extensor digitorum longus muscle recovered to nearly normal levels in 24 weeks. Simultaneously, real-time polymerase chain reaction results showed that upregulation of calcium-ATPase (a membrane protein that transports calcium out of nerve fibers) mRNA peaked at 12 weeks. These results suggest that without intervention, the peak in calcium-ATPase mRNA expression in the injured nerve occurs after the peak in calcium accumulation, and CMAP recovery continues beyond 24 weeks. Immediately using calcium-modulating agents after crushed nerve injury improved functional recovery. These studies suggest that a crucial time frame in which to initiate effective clinical approaches to accelerate calcium clearance and nerve regeneration would be prior to 2 weeks post injury. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Yuhui Yan
- Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee
| | - Feng-Yi Shen
- Froedtert Health-Community Memorial Hospital, Medical College of Wisconsin, Milwaukee
| | - Michael Agresti
- Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee
| | - Lin-Ling Zhang
- Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee
| | - Hani S Matloub
- Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee
| | - John A LoGiudice
- Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee
| | - Robert Havlik
- Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee
| | - Jifeng Li
- Department of Hand Surgery, Huashan Hospital, Fudan University and Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, China
| | - Yu-Dong Gu
- Department of Hand Surgery, Huashan Hospital, Fudan University and Key Laboratory of Hand Reconstruction, Ministry of Health, Shanghai Key Laboratory of Peripheral Nerve and Microsurgery, Shanghai, China
| | - Ji-Geng Yan
- Department of Plastic and Reconstructive Surgery, Medical College of Wisconsin, Milwaukee
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Chung MK, Campbell JN. Use of Capsaicin to Treat Pain: Mechanistic and Therapeutic Considerations. Pharmaceuticals (Basel) 2016; 9:ph9040066. [PMID: 27809268 PMCID: PMC5198041 DOI: 10.3390/ph9040066] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 10/25/2016] [Accepted: 10/27/2016] [Indexed: 12/31/2022] Open
Abstract
Capsaicin is the pungent ingredient of chili peppers and is approved as a topical treatment of neuropathic pain. The analgesia lasts for several months after a single treatment. Capsaicin selectively activates TRPV1, a Ca2+-permeable cationic ion channel that is enriched in the terminals of certain nociceptors. Activation is followed by a prolonged decreased response to noxious stimuli. Interest also exists in the use of injectable capsaicin as a treatment for focal pain conditions, such as arthritis and other musculoskeletal conditions. Recently injection of capsaicin showed therapeutic efficacy in patients with Morton’s neuroma, a painful foot condition associated with compression of one of the digital nerves. The relief of pain was associated with no change in tactile sensibility. Though injection evokes short term pain, the brief systemic exposure and potential to establish long term analgesia without other sensory changes creates an attractive clinical profile. Short-term and long-term effects arise from both functional and structural changes in nociceptive terminals. In this review, we discuss how local administration of capsaicin may induce ablation of nociceptive terminals and the clinical implications.
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Affiliation(s)
- Man-Kyo Chung
- Department of Neural and Pain Sciences, University of Maryland, School of Dentistry, Program in Neuroscience, Center to Advance Chronic Pain Research, Baltimore, MD 21201, USA.
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14
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Yan JG, Logiudice J, Davis J, Zhang LL, Agresti M, Sanger J, Matloub HS, Havlik R. Calcitonin pump improves nerve regeneration after transection injury and repair. Muscle Nerve 2014; 51:229-34. [PMID: 24809806 DOI: 10.1002/mus.24281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/06/2014] [Indexed: 11/11/2022]
Abstract
INTRODUCTION After nerve injury, excessive calcium impedes nerve regeneration. We previously showed that calcitonin improved nerve regeneration in crush injury. We aimed to validate the direct effect of calcitonin on transected and repaired nerve. METHODS Two rat groups (n = 8) underwent sciatic nerve transection followed by direct repair. In the calcitonin group, a calcitonin-filled mini-osmotic pump was implanted subcutaneously, with a catheter parallel to the repaired nerve. The control group underwent repair only, without a pump. Evaluation and comparison between the groups included: (1) compound muscle action potential recording of the extensor digitorum longus (EDL) muscle; (2) tetanic muscle force test of EDL; (3) nerve calcium concentration; and (4) nerve fiber count and calcified spot count. RESULTS The calcitonin pump group showed superior recovery. CONCLUSIONS Calcitonin affects injured and repaired peripheral nerve directly. The calcitonin-filled mini-osmotic pump improved nerve functional recovery by accelerating calcium absorption from the repaired nerve. This finding has potential clinical applications.
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Affiliation(s)
- Ji-Geng Yan
- Department of Plastic Surgery, Medical College of Wisconsin, 8700 Watertown Plank Road, Milwaukee, Wisconsin, 53226, USA
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15
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Lai TW, Zhang S, Wang YT. Excitotoxicity and stroke: identifying novel targets for neuroprotection. Prog Neurobiol 2013; 115:157-88. [PMID: 24361499 DOI: 10.1016/j.pneurobio.2013.11.006] [Citation(s) in RCA: 776] [Impact Index Per Article: 70.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 11/28/2013] [Accepted: 11/29/2013] [Indexed: 01/22/2023]
Abstract
Excitotoxicity, the specific type of neurotoxicity mediated by glutamate, may be the missing link between ischemia and neuronal death, and intervening the mechanistic steps that lead to excitotoxicity can prevent stroke damage. Interest in excitotoxicity began fifty years ago when monosodium glutamate was found to be neurotoxic. Evidence soon demonstrated that glutamate is not only the primary excitatory neurotransmitter in the adult brain, but also a critical transmitter for signaling neurons to degenerate following stroke. The finding led to a number of clinical trials that tested inhibitors of excitotoxicity in stroke patients. Glutamate exerts its function in large by activating the calcium-permeable ionotropic NMDA receptor (NMDAR), and different subpopulations of the NMDAR may generate different functional outputs, depending on the signaling proteins directly bound or indirectly coupled to its large cytoplasmic tail. Synaptic activity activates the GluN2A subunit-containing NMDAR, leading to activation of the pro-survival signaling proteins Akt, ERK, and CREB. During a brief episode of ischemia, the extracellular glutamate concentration rises abruptly, and stimulation of the GluN2B-containing NMDAR in the extrasynaptic sites triggers excitotoxic neuronal death via PTEN, cdk5, and DAPK1, which are directly bound to the NMDAR, nNOS, which is indirectly coupled to the NMDAR via PSD95, and calpain, p25, STEP, p38, JNK, and SREBP1, which are further downstream. This review aims to provide a comprehensive summary of the literature on excitotoxicity and our perspectives on how the new generation of excitotoxicity inhibitors may succeed despite the failure of the previous generation of drugs.
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Affiliation(s)
- Ted Weita Lai
- Graduate Institute of Clinical Medical Science, China Medical University, 91 Hsueh-Shih Road, 40402 Taichung, Taiwan; Translational Medicine Research Center, China Medical University Hospital, 2 Yu-De Road, 40447 Taichung, Taiwan.
| | - Shu Zhang
- Translational Medicine Research Center, China Medical University Hospital, 2 Yu-De Road, 40447 Taichung, Taiwan; Brain Research Center, University of British Columbia, 2211 Wesbrook Mall, V6T 2B5 Vancouver, Canada
| | - Yu Tian Wang
- Brain Research Center, University of British Columbia, 2211 Wesbrook Mall, V6T 2B5 Vancouver, Canada.
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16
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The effect of calcium modulating agents on peripheral nerve recovery after crush. J Neurosci Methods 2013; 217:54-62. [DOI: 10.1016/j.jneumeth.2013.04.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 03/26/2013] [Accepted: 04/15/2013] [Indexed: 01/03/2023]
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17
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Increased brain tissue sodium concentration in Huntington's Disease — A sodium imaging study at 4T. Neuroimage 2012; 63:517-24. [DOI: 10.1016/j.neuroimage.2012.07.009] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Revised: 07/05/2012] [Accepted: 07/06/2012] [Indexed: 02/05/2023] Open
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18
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Leonelli M, Martins DO, Britto LRG. TRPV1 receptors are involved in protein nitration and Müller cell reaction in the acutely axotomized rat retina. Exp Eye Res 2010; 91:755-68. [PMID: 20826152 DOI: 10.1016/j.exer.2010.08.026] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Revised: 06/24/2010] [Accepted: 08/30/2010] [Indexed: 12/20/2022]
Abstract
We report here the protein expression of TRPV1 receptor in axotomized rat retinas and its possible participation in mechanisms involved in retinal ganglion cell (RGC) death. Adult rats were subjected to unilateral, intraorbital axotomy of the optic nerve, and the retinal tissue was removed for further processing. TRPV1 total protein expression decreased progressively after optic nerve transection, reaching 66.2% of control values 21 days after axotomy. The number of cells labeled for TRPV1 in the remnant GCL decreased after 21 days post-lesion (to 63%). Fluoro-Jade B staining demonstrated that the activation of TRPV1 in acutely-lesioned eyes elicited more intense neuronal degeneration in the GCL and in the inner nuclear layer than in sham-operated retinas. A single intraocular injection of capsazepine (100 μM), a TRPV1 antagonist, 5 days after optic nerve lesion, decreased the number of GFAP-expressing Müller cells (72.5% of control values) and also decreased protein nitration in the retinal vitreal margin (75.7% of control values), but did not affect lipid peroxidation. Furthermore, retinal explants were treated with capsaicin (100 μM), and remarkable protein nitration was then present, which was reduced by blockers of the constitutive and inducible nitric oxide synthases (7-NI and aminoguanidine, respectively). TRPV1 activation also increased GFAP expression, which was reverted by both TRPV1 antagonism with capsazepine and by 7-NI and aminoguanidine. Given that Müller cells do not express TRPV1, we suppose that the increased GFAP expression in these cells might be elicited by TRPV1 activation and by its indirect effect upon nitric oxide overproduction and peroxynitrite formation. We incubated Fluorogold pre-labeled retinal explants in the presence of capsazepine (1 μM) during 48 h. The numbers of surviving RGCs stained with fluorogold and the numbers of apoptotic cells in the GCL detected with TUNEL were similar in lesioned and control retinas. We conclude that TRPV1 receptor expression decreased after optic nerve injury due to death of TRPV1-containing cells. Furthermore, these data indicate that TRPV1 might be involved in intrinsic protein nitration and Müller cell reaction observed after optic nerve injury.
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Affiliation(s)
- Mauro Leonelli
- Department of Physiology & Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP 05508-900, Brazil.
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19
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Negri L, Lattanzi R, Giannini E, Melchiorri P. Modulators of pain: Bv8 and prokineticins. Curr Neuropharmacol 2010; 4:207-15. [PMID: 18615143 DOI: 10.2174/157015906778019518] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2006] [Revised: 03/06/2006] [Accepted: 03/07/2006] [Indexed: 12/14/2022] Open
Abstract
Bv8 is a small protein secreted by frog skin. Mammalian homologues of Bv8, the prokineticins PK1 and PK2, and their G-protein coupled receptors PKR1 and PKR2 have been identified and linked to several biological effects. Bv8 elicits a dose-dependent reduction in nociceptive threshold to thermal and mechanical stimuli applied to the skin of tail and paw of rats and mice and increases the sensitivity to nociceptive mediators as capsaicin and prostaglandins. The receptors for Bv8/PKs are present in a fraction of peptidergic population of C-fibre neurons, and in a fraction of A myelinated-fibre neurons. In mouse and rat dorsal root ganglia, PKR-expressing neurons also express TRPV1 and the activation of PKRs sensitises TPRV1 to the action of capsaicin. Mice lacking PKR1 gene exhibit impaired Bv8-induced hyperalgesia, develop deficient responses to noxious heat, capsaicin and protons and show reduced thermal and mechanical hypersensitivity to paw inflammation, indicating a requirement for PKR1 signalling associated with activation and sensitisation of primary afferent fibres. PKs are highly expressed by neutrophils and other inflammatory cells and must be considered as new pronociceptive mediators in inflammatory tissues. Bv8-like hyperalgesic activity was demonstrated in extracts of rat inflammatory granulocytes. Bv8 stimulate macrophage and T lymphocyte to differentiate between an inflammatory and Th1 profile indicating that Bv8/PK proteins play a role in immuno-inflammatory responses. Blockade of PKRs may represent a novel therapeutic strategy in acute and inflammatory pain conditions.
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Affiliation(s)
- Lucia Negri
- Department of Human Physiology and Pharmacology, University of Rome "La Sapienza" Roma, Italia.
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20
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Tan PL, Katsanis N. Thermosensory and mechanosensory perception in human genetic disease. Hum Mol Genet 2009; 18:R146-55. [PMID: 19808790 DOI: 10.1093/hmg/ddp412] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Peripheral sensory perception is established through an elaborate network of specialized neurons that mediate the translation of extraorganismal stimuli through the use of a broad array of receptors and downstream effector molecules. Studies of human genetic disorders, as well as mouse and other animal models, have identified some of the key molecules necessary for peripheral innervation and function. These findings have, in turn, yielded new insights into the developmental networks and homeostatic mechanisms necessary for the transformation of external stimuli into interpretable electrical impulses. In this review, we will summarize and discuss some of the genes/proteins implicated in two particular aspects of sensory perception, thermosensation and mechanosensation, highlighting pathways whose perturbation leads to both isolated and syndromic sensory deficits.
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Affiliation(s)
- Perciliz L Tan
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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21
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St. Pierre M, Reeh PW, Zimmermann K. Differential effects of TRPV channel block on polymodal activation of rat cutaneous nociceptors in vitro. Exp Brain Res 2009; 196:31-44. [DOI: 10.1007/s00221-009-1808-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2009] [Accepted: 04/07/2009] [Indexed: 02/02/2023]
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22
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The pharmacological challenge to tame the transient receptor potential vanilloid-1 (TRPV1) nocisensor. Br J Pharmacol 2008; 155:1145-62. [PMID: 18806809 DOI: 10.1038/bjp.2008.351] [Citation(s) in RCA: 137] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The transient receptor potential vanilloid-1 (TRPV1) cation channel is a receptor that is activated by heat (>42 degrees C), acidosis (pH<6) and a variety of chemicals among which capsaicin is the best known. With these properties, TRPV1 has emerged as a polymodal nocisensor of nociceptive afferent neurones, although some non-neuronal cells and neurones in the brain also express TRPV1. The activity of TRPV1 is controlled by a multitude of regulatory mechanisms that either cause sensitization or desensitization of the channel. As many proalgesic pathways converge on TRPV1 and this nocisensor is upregulated and sensitized by inflammation and injury, TRPV1 is thought to be a central transducer of hyperalgesia and a prime target for the pharmacological control of pain. As a consequence, TRPV1 agonists causing defunctionalization of sensory neurones and a large number of TRPV1 blockers have been developed, some of which are in clinical trials. A major drawback of many TRPV1 antagonists is their potential to cause hyperthermia, and their long-term use may carry further risks because TRPV1 has important physiological functions in the peripheral and central nervous system. The challenge, therefore, is to pharmacologically differentiate between the physiological and pathological implications of TRPV1. There are several possibilities to focus therapy specifically on those TRPV1 channels that contribute to disease processes. These approaches include (i) site-specific TRPV1 antagonists, (ii) modality-specific TRPV1 antagonists, (iii) uncompetitive TRPV1 (open channel) blockers, (iv) drugs interfering with TRPV1 sensitization, (v) drugs interfering with intracellular trafficking of TRPV1 and (vi) TRPV1 agonists for local administration.
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23
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Goswami C, Hucho T. Submembraneous microtubule cytoskeleton: biochemical and functional interplay of TRP channels with the cytoskeleton. FEBS J 2008; 275:4684-99. [PMID: 18754773 DOI: 10.1111/j.1742-4658.2008.06617.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Much work has focused on the electrophysiological properties of transient receptor potential channels. Recently, a novel aspect of importance emerged: the interplay of transient receptor potential channels with the cytoskeleton. Recent data suggest a direct interaction and functional repercussion for both binding partners. The bi-directionality of physical and functional interaction renders therefore, the cytoskeleton a potent integration point of complex biological signalling events, from both the cytoplasm and the extracellular space. In this minireview, we focus mostly on the interaction of the cytoskeleton with transient receptor potential vanilloid channels. Thereby, we point out the functional importance of cytoskeleton components both as modulator and as modulated downstream effector. The resulting implications for patho-biological situations are discussed.
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Affiliation(s)
- Chandan Goswami
- Department for Molecular Human Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany.
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24
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Maggi CA. The dual function of capsaicin-sensitive sensory nerves in the bladder and urethra. CIBA FOUNDATION SYMPOSIUM 2007; 151:77-83; discussion 83-90. [PMID: 2226067 DOI: 10.1002/9780470513941.ch5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The sensory innervation of the urinary bladder and urethra plays a key role in a variety of reflexes involved in urine storage and voiding. Dysfunction of these systems is a possible cause of many disturbances related to urine continence but basic knowledge in this field has been hampered by the lack of tools for studying sensory nerves. The use of capsaicin, the pungent ingredient of red peppers, allowed us to investigate the anatomical and functional properties of a specific subset of sensory neurons in the lower urinary tract. These 'capsaicin-sensitive' neurons play a dual sensory and 'efferent' function, determined by transmitter release from their central and peripheral nerve endings. Tachykinins, including substance P, and other neuropeptides such as calcitonin gene-related peptide, mediate the functions of these sensory neurons. The 'sensory' function includes regulation of micturition threshold, activation of cardiovascular reflexes and perception of pain from the urinary bladder. The 'efferent' function includes local regulation of muscle cell activity, nerve excitability, blood flow and plasma protein extravasation. Recent data suggest that capsaicin-sensitive sensory nerves could be present in the human bladder.
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Affiliation(s)
- C A Maggi
- Pharmacology Department, A. Menarini Pharmaceuticals, Florence, Italy
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25
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Caterina MJ. Transient receptor potential ion channels as participants in thermosensation and thermoregulation. Am J Physiol Regul Integr Comp Physiol 2006; 292:R64-76. [PMID: 16973931 DOI: 10.1152/ajpregu.00446.2006] [Citation(s) in RCA: 287] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Living organisms must evaluate changes in environmental and internal temperatures to mount appropriate physiological and behavioral responses conducive to survival. Classical physiology has provided a wealth of information regarding the specialization of thermosensory functions among subclasses of peripheral sensory neurons and intrinsically thermosensitive neurons within the hypothalamus. However, until recently, the molecular mechanisms by which these cells carry out thermometry have remained poorly understood. The demonstration that certain ion channels of the transient receptor potential (TRP) family can be activated by increases or decreases in ambient temperature, along with the recognition of their heterogeneous expression patterns and heterogeneous temperature sensitivities, has led investigators to evaluate these proteins as candidate endogenous thermosensors. Much of this work has involved one specific channel, TRP vanilloid 1 (TRPV1), which is both a receptor for capsaicin and related pungent vanilloid compounds and a "heat receptor," capable of directly depolarizing neurons in response to temperatures >42 degrees C. Evidence for a contribution of TRPV1 to peripheral thermosensation has come from pharmacological, physiological, and genetic approaches. In contrast, although capsaicin-sensitive mechanisms clearly influence core body temperature regulation, the specific contribution of TRPV1 to this process remains a matter of debate. Besides TRPV1, at least six additional thermally sensitive TRP channels have been identified in mammals, and many of these also appear to participate in thermosensation. Moreover, the identification of invertebrate TRP channels, whose genetic ablation alters thermally driven behaviors, makes it clear that thermosensation represents an evolutionarily conserved role of this ion channel family.
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Affiliation(s)
- Michael J Caterina
- Department of Biological Chemistry, Center for Sensory Biology, Johns Hopkins School of Medicine, 725 N. Wolfe St., Baltimore, MD 21205, USA.
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26
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Goswami C, Dreger M, Otto H, Schwappach B, Hucho F. Rapid disassembly of dynamic microtubules upon activation of the capsaicin receptor TRPV1. J Neurochem 2005; 96:254-66. [PMID: 16336230 DOI: 10.1111/j.1471-4159.2005.03551.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The transmission of pain signalling involves the cytoskeleton, but mechanistically this is poorly understood. We recently demonstrated that the capsaicin receptor TRPV1, a non-selective cation channel expressed by nociceptors that is capable of detecting multiple pain-producing stimuli, directly interacts with the tubulin cytoskeleton. We hypothesized that the tubulin cytoskeleton is a downstream effector of TRPV1 activation. Here we show that activation of TRPV1 results in the rapid disassembly of microtubules, but not of the actin or neurofilament cytoskeletons. TRPV1 activation mainly affects dynamic microtubules that contain tyrosinated tubulins, whereas stable microtubules are apparently unaffected. The C-terminal fragment of TRPV1 exerts a stabilizing effect on microtubules when over-expressed in F11 cells. These findings suggest that TRPV1 activation may contribute to cytoskeleton remodelling and so influence nociception.
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Affiliation(s)
- C Goswami
- Freie Universität Berlin, Institut für Chemie/Biochemie, Berlin, Germany
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27
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Nagy I, Sántha P, Jancsó G, Urbán L. The role of the vanilloid (capsaicin) receptor (TRPV1) in physiology and pathology. Eur J Pharmacol 2005; 500:351-69. [PMID: 15464045 DOI: 10.1016/j.ejphar.2004.07.037] [Citation(s) in RCA: 198] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2004] [Indexed: 02/06/2023]
Abstract
The cloning of the vanilloid receptor 1 opened a floodgate for discoveries regarding the function of this complex molecule. It has been found that, in addition to heat, protons and vanilloids, this receptor also responds to various endogenous ligands. Furthermore, it has been also emerged that, through associations with other molecules, the vanilloid receptor 1 plays an important role in the integration of various stimuli and modulation of cellular excitability. Although, originally, the vanilloid receptor 1 was associated with nociceptive primary afferent fibres, it has been gradually revealed that it is broadly expressed in the brain, epidermis and visceral cells. The expression pattern of the vanilloid receptor 1 indicates that it could be involved in various physiological functions and in the pathomechanisms of diverse diseases. Here, we summarise the molecular, pharmacological and physiological characteristics, and putative functions, of the vanilloid receptor 1, and discuss the therapeutic potential of this molecule.
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Affiliation(s)
- István Nagy
- Department of Anaesthetics and Intensive Care, Imperial College London, Chelsea and Westminster Hospital, 369 Fulham Road, London SW10 9NH, United Kingdom.
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28
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Abstract
Mammalian transient receptor potential (TRP) channels consist of six related protein sub-families that are involved in a variety of pathophysiological function, and disease development. The TRPV1 channel, a member of the TRPV sub-family, is identified by expression cloning using the "hot" pepper-derived vanilloid compound capsaicin as a ligand. Therefore, TRPV1 is also referred as the vanilloid receptor (VR1) or the capsaicin receptor. VR1 is mainly expressed in a subpopulation of primary afferent neurons that project to cardiovascular and renal tissues. These capsaicin-sensitive primary afferent neurons are not only involved in the perception of somatic and visceral pain, but also have a "sensory-effector" function. Regarding the latter, these neurons release stored neuropeptides through a calcium-dependent mechanism via the binding of capsaicin to VR1. The most studied sensory neuropeptides are calcitonin gene-related peptide (CGRP) and substance P (SP), which are potent vasodilators and natriuretic/diuretic factors. Recent evidence using the model of neonatal degeneration of capsaicin-sensitive sensory nerves revealed novel mechanisms that underlie increased salt sensitivity and several experimental models of hypertension. These mechanisms include insufficient suppression of plasma renin activity and plasma aldosterone levels subsequent to salt loading, enhancement of sympathoexcitatory response in the face of a salt challenge, activation of the endothelin-1 receptor, and impaired natriuretic response to salt loading in capsaicin-pretreated rats. These data indicate that sensory nerves counterbalance the prohypertensive effects of several neurohormonal systems to maintain normal blood pressure when challenged with salt loading. The therapeutic utilities of vanilloid compounds, endogenous agonists, and sensory neuropeptides are also discussed.
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Affiliation(s)
- Donna H Wang
- Department of Medicine, College of Human Medicine, Michigan State University, East Lansing, MI 48825, USA.
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29
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Abstract
Inflammatory reaction following a spinal cord injury (SCI) contributes substantially to secondary effects, with both beneficial and devastating effects. This review summarizes the current knowledge concerning the structural features (vascular, cellular, and biochemical events) of SCI and gives an overview of the regulation of post-traumatic inflammation.
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Affiliation(s)
- O N Hausmann
- Neurosurgical Department, University Clinics Basel, Switzerland
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30
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Liu M, Liu MC, Magoulas C, Priestley JV, Willmott NJ. Versatile regulation of cytosolic Ca2+ by vanilloid receptor I in rat dorsal root ganglion neurons. J Biol Chem 2003; 278:5462-72. [PMID: 12454015 DOI: 10.1074/jbc.m209111200] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Analysis of small dorsal root ganglion (DRG) neurons revealed novel functions for vanilloid receptor 1 (VR1) in the regulation of cytosolic Ca(2+). The VR1 agonist capsaicin induced Ca(2+) mobilization from intracellular stores in the absence of extracellular Ca(2+), and this release was inhibited by the VR1 antagonist capsazepine but was unaffected by the phospholipase C inhibitor xestospongins, indicating that Ca(2+) mobilization was dependent on capsaicin receptor binding and was not due to intracellular inositol-1,4,5-trisphosphate generation. Confocal microscopy revealed extensive expression of VR1 on endoplasmic reticulum, consistent with VR1 operating as a Ca(2+) release receptor. The main part of the capsaicin-releasable Ca(2+) store was insensitive to thapsigargin, a selective endoplasmic reticulum Ca(2+)-ATPase inhibitor, suggesting that VR1 might be predominantly localized to a thapsigargin-insensitive endoplasmic reticulum Ca(2+) store. In addition, VR1 was observed to behave as a store-operated Ca(2+) influx channel. In DRG neurons, capsazepine attenuated Ca(2+) influx following thapsigargin-induced Ca(2+) store depletion and inhibited thapsigargin-induced inward currents. Conversely, transfected HEK-293 cells expressing VR1 showed enhanced Ca(2+) influx and inward currents following Ca(2+) store depletion. Combined data support topographical and functional diversity for VR1 in the regulation of cytosolic Ca(2+) with the plasma membrane-associated form behaving as a store-operated Ca(2+) influx channel and endoplasmic reticulum-associated VR1 possibly functioning as a Ca(2+) release receptor in sensory neurons.
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Affiliation(s)
- Min Liu
- Department of Neuroscience, St. Bartholomew's, Mile End Road, London EC1 4NS, United Kingdom
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31
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Szöke E, Seress L, Szolcsányi J. Neonatal capsaicin treatment results in prolonged mitochondrial damage and delayed cell death of B cells in the rat trigeminal ganglia. Neuroscience 2002; 113:925-37. [PMID: 12182898 DOI: 10.1016/s0306-4522(02)00208-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Capsaicin acts on the vanilloid receptor subtype 1, a noxious heat-gated cation channel located on a major subgroup of nociceptive primary afferent neurons. Following the systemic capsaicin treatment of neonatal rats, the loss of B-type sensory neurons in trigeminal ganglion of adult rats with chemoanalgesia and abolition of neurogenic inflammation was investigated. Our quantitative morphometric analysis revealed that in the trigeminal ganglion of neonatal rats treated with 50 mg/kg s.c. capsaicin, the total number of neurons, morphology of B-type cells and cell-size histograms did not differ from that of the controls 1 or 5 days after treatment. These observations indicate that early cell death does not play a significant part in the loss of B-type cells, which in our sample was 39.4% on the 19th day. However under the electron microscope pronounced selective mitochondrial swelling with disorganized cristae was observed in B-type neurons at 1-20 weeks after capsaicin treatment. Daily treatment with nerve growth factor (NGF, 10 x 100 microg/kg s.c.), started 1 day after capsaicin injection, prevented the loss of B-type cells but did not counteract the development of long-lasting mitochondrial damage. After NGF treatment, partial restitution of chemonociception to capsaicin instillation into the eye occurred but capsaicin-induced inhibition of neurogenic plasma extravasation in the hindpaw evoked by topical application of mustard oil remained unaltered. We conclude, that capsaicin treatment in neonatal rats, as in the adults, destroys terminal parts of the sensory neurons supplied by vanilloid receptors and induces long-lasting mitochondrial swelling in the soma. We hypothesize that loss of NGF uptake results in delayed cell death of B-type neurons in neonates.
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Affiliation(s)
- E Szöke
- Department of Pharmacology and Pharmacotherapy, Neuropharmacology Research Group of the Hungarian Academy of Sciences, Faculty of Medicine of University of Pécs, Szigeti u. 12, 7643 Pécs, Hungary
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Pini A, Lynn B. C-fibre Function During the 6 Weeks Following Brief Application of Capsaicin to a Cutaneous Nerve in the Rat. Eur J Neurosci 2002; 3:274-284. [PMID: 12106205 DOI: 10.1111/j.1460-9568.1991.tb00089.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The functional properties of afferent fibres, especially C-fibres, have been studied over the 46 days following application of capsaicinoids to a segment of the saphenous nerve in the rat. After 1 - 3 days, approximately half of the C-afferents were found to be non-conducting at or immediately distal to the treatment site. By 6 - 9 days there was some recovery of conduction at the treatment site, but few of the conducting fibres were excitable from the skin. From 12 days onwards, C-fibre conduction in the segment of nerve both proximal and distal to the treatment site was reduced and of the conducting fibres relatively few had cutaneous receptive fields. In the sample of C-fibres with cutaneous receptive fields the proportion of polymodal nociceptors was reduced markedly compared with control values. Analysis of the numbers of surviving units shows a large effect on C-polymodal nociceptors, but no significant change in the numbers of any other type of afferent unit. At 2 weeks, when C-fibre numbers were reduced to about one third, there was a virtual abolition of antidromic vasodilatation and an 85% fall in skin substance P levels. The synthetic capsaicinoid, NE-21610, had similar actions to capsaicin and was more potent in depleting skin substance P levels. These results confirm that capsaicinoids produce a selective local lesion on nociceptive C-fibres in rat cutaneous nerves. In addition, the transient and partial nature of functional recovery indicates that capsaicin may also cause a longer-term toxic action that inhibits significant regeneration.
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Affiliation(s)
- Adrian Pini
- Department of Physiology, University College London, Gower Street, London WC1E 6BT, UK
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Grant ER, Dubin AE, Zhang SP, Zivin RA, Zhong Z. Simultaneous intracellular calcium and sodium flux imaging in human vanilloid receptor 1 (VR1)-transfected human embryonic kidney cells: a method to resolve ionic dependence of VR1-mediated cell death. J Pharmacol Exp Ther 2002; 300:9-17. [PMID: 11752091 DOI: 10.1124/jpet.300.1.9] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The vanilloid receptor 1 (VR1) is a ligand-gated, nonselective cation channel important for the sensory processing of painful stimuli. Activation of VR1 leads to increases in intracellular concentrations of calcium and sodium. Prolonged activation of VR1 in mammalian expression systems leads to cell death. The mechanism of VR1-mediated toxicity may have relevance to pathophysiological processes that can occur in neurons. Therefore, we have evaluated the relative contributions of intracellular calcium and sodium changes to VR1-mediated toxicity in human embryonic kidney 293 cells stably transfected with the human VR1 channel. The data demonstrate that VR1 receptor agonists capsaicin and resiniferatoxin lead to a sustained increase in intracellular calcium and sodium in a concentration-dependent manner, followed by cell death. Pretreatment with VR1 receptor antagonists capsazepine or ruthenium red block both the calcium and sodium responses to agonists, and block agonist-induced cell death in a concentration-dependent manner. However, addition of antagonists several minutes after agonists selectively reverses the agonist-induced increase in intracellular calcium, but does not reverse the elevated intracellular sodium concentration. Nonetheless, antagonists retain protective efficacy against capsaicin toxicity when added several minutes after capsaicin, conditions in which the cells still manifest elevated intracellular sodium, but not elevated intracellular calcium. In addition, a transient VR1-mediated increase in intracellular calcium that returns to baseline within minutes, induced by a rapid drop in pH, from pH 7.5 to pH 6.3, also does not lead to cell death. Collectively, these data demonstrate that the most important intracellular ionic change for mediating VR1-dependent toxicity is a sustained increase of calcium.
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Affiliation(s)
- Elfrida R Grant
- Drug Discovery, R. W. Johnson Pharmaceutical Research Institute, Raritan, New Jersey 08869, USA
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34
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Abstract
The detection of painful stimuli occurs primarily at the peripheral terminals of specialized sensory neurons called nociceptors. These small-diameter neurons transduce signals of a chemical, mechanical, or thermal nature into action potentials and transmit this information to the central nervous system, ultimately eliciting a perception of pain or discomfort. Little is known about the proteins that detect noxious stimuli, especially those of a physical nature. Here we review recent advances in the molecular characterization of the capsaicin (vanilloid) receptor, an excitatory ion channel expressed by nociceptors, which contributes to the detection and integration of pain-producing chemical and thermal stimuli. The analysis of vanilloid receptor gene knockout mice confirms the involvement of this channel in pain sensation, as well as in hypersensitivity to noxious stimuli following tissue injury. At the same time, these studies demonstrate the existence of redundant mechanisms for the sensation of heat-evoked pain.
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Affiliation(s)
- M J Caterina
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
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35
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Olajos EJ, Salem H. Riot control agents: pharmacology, toxicology, biochemistry and chemistry. J Appl Toxicol 2001; 21:355-91. [PMID: 11746179 DOI: 10.1002/jat.767] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The desired effect of all riot control agents is the temporary disablement of individuals by way of intense irritation of the mucous membranes and skin. Generally, riot control agents can produce acute site-specific toxicity where sensory irritation occurs. Early riot control agents, namely, chloroacetophenone (CN) and chlorodihydrophenarsazine (DM), have been replaced with 'safer' agents such as o-chlorobenzylidene malononitrile (CS) and oleoresin of capsicum (OC). Riot control agents are safe when used as intended: however, the widespread use of riot control agents raises questions and concerns regarding their health effects and safety. A large margin exists between dosages that produce harassment and dosages likely to cause adverse health effects for modern riot control agents such as CS and dibenz[b,f]1 : 4-oxazepine (CR). Yet, despite the low toxicity of modern riot control agents, these compounds are not entirely without risk. The risk of toxicity increases with higher exposure levels and prolonged exposure durations. Ocular, pulmonary and dermal injury may occur on exposure to high levels of these substances, and exposure to riot control agents in enclosed spaces may produce significant toxic effects. Reported deaths are few involving riot control agents, and then only under conditions of prolonged exposure and high concentrations. Recently, concern has focused on the deaths resulting from law enforcement use of OC, a riot control agent generally regarded as safe because it is a natural product. As with other xenobiotics, not enough is known concerning the long-term/chronic effects of riot control agents. Clearly, there is considerable need for additional research to define and delineate the biological and toxicological actions of riot control agents and to illuminate the full health consequences of these compounds as riot control agents.
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Affiliation(s)
- E J Olajos
- US Army, Edgewood Chemical and Biological Center, 5183 Blackhawk Rd, Aberdeeen Proving Ground, MD 21010-5424, USA
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36
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Olah Z, Szabo T, Karai L, Hough C, Fields RD, Caudle RM, Blumberg PM, Iadarola MJ. Ligand-induced dynamic membrane changes and cell deletion conferred by vanilloid receptor 1. J Biol Chem 2001; 276:11021-30. [PMID: 11124944 DOI: 10.1074/jbc.m008392200] [Citation(s) in RCA: 188] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The real time dynamics of vanilloid-induced cytotoxicity and the specific deletion of nociceptive neurons expressing the wild-type vanilloid receptor (VR1) were investigated. VR1 was C-terminally tagged with either the 27-kDa enhanced green fluorescent protein (eGFP) or a 12-amino acid epsilon-epitope. Upon exposure to resiniferatoxin, VR1eGFP- or VR1epsilon-expressing cells exhibited pharmacological responses similar to those of cells expressing the untagged VR1. Within seconds of vanilloid exposure, the intracellular free calcium ([Ca(2+)](i)) was elevated in cells expressing VR1. A functional pool of VR1 also was localized to the endoplasmic reticulum that, in the absence of extracellular calcium, also was capable of releasing calcium upon agonist treatment. Confocal imaging disclosed that resiniferatoxin treatment induced vesiculation of the mitochondria and the endoplasmic reticulum ( approximately 1 min), nuclear membrane disruption (5-10 min), and cell lysis (1-2 h). Nociceptive primary sensory neurons endogenously express VR1, and resiniferatoxin treatment induced a sudden increase in [Ca(2+)](i) and mitochondrial disruption which was cell-selective, as glia and non-VR1-expressing neurons were unaffected. Early hallmarks of cytotoxicity were followed by specific deletion of VR1-expressing cells. These data demonstrate that vanilloids disrupt vital organelles within the cell body and, if administered to sensory ganglia, may be employed to rapidly and selectively delete nociceptive neurons.
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Affiliation(s)
- Z Olah
- Neuronal Gene Expression Unit, Pain and Neurosensory Mechanisms Branch, NIDCR, the Laboratory of Cellular Carcinogenesis and Tumor Promotion, NCI, National Institutes of Health, Bethesda, Maryland 20892, USA.
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37
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Gschossmann JM, Chaban VV, McRoberts JA, Raybould HE, Young SH, Ennes HS, Lembo T, Mayer EA. Mechanical activation of dorsal root ganglion cells in vitro: comparison with capsaicin and modulation by kappa-opioids. Brain Res 2000; 856:101-10. [PMID: 10677616 DOI: 10.1016/s0006-8993(99)02353-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The aim of this study was to characterize plasma membrane pathways involved in the intracellular calcium ([Ca(2+)](i)) response of small DRG neurons to mechanical stimulation and the modulation of these pathways by kappa-opioids. [Ca(2+)](i) responses were measured by fluorescence video microscopy of Fura-2 labeled lumbosacral DRG neurons obtained from adult rats in short-term primary culture. Transient focal mechanical stimulation of the soma, or brief superfusion with 300 nM capsaicin, resulted to [Ca(2+)](i) increases which were abolished in Ca(2+)-free solution, but unaffected by lanthanum (25 microM) or tetrodotoxin (10(-6) M). 156 out of 465 neurons tested (34%) showed mechanosensitivity while 55 out of 118 neurons (47%) were capsaicin-sensitive. Ninty percent of capsaicin-sensitive neurons were mechanosensitive. Gadolinium (Gd(3+); 250 microM) and amiloride (100 microM) abolished the [Ca(2+)](i) transient in response to mechanical stimulation, but had no effect on capsaicin-induced [Ca(2+)](i) transients. The kappa-opioid agonists U50,488 and fedotozine showed a dose-dependent inhibition of mechanically stimulated [Ca(2+)](i) transients but had little effect on capsaicin-induced [Ca(2+)](i) transients. The inhibitory effect of U50,488 was abolished by the kappa-opioid antagonist nor-Binaltorphimine dihydrochloride (nor-BNI; 100 nM), and by high concentrations of naloxone (30-100 nM), but not by low concentrations of naloxone (3 nM). We conclude that mechanically induced [Ca(2+)](i) transients in small diameter DRG somas are mediated by influx of Ca(2+) through a Gd(3+)- and amiloride-sensitive plasma membrane pathway that is co-expressed with capsaicin-sensitive channels. Mechanical-, but not capsaicin-mediated, Ca(2+) transients are sensitive to kappa-opioid agonists.
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MESH Headings
- 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer/pharmacology
- Amiloride/pharmacology
- Animals
- Benzyl Compounds/pharmacology
- Calcium/metabolism
- Capsaicin/pharmacology
- Cells, Cultured
- Gadolinium/pharmacology
- Ganglia, Spinal/cytology
- Ganglia, Spinal/physiology
- In Vitro Techniques
- Kinetics
- Male
- Naltrexone/analogs & derivatives
- Naltrexone/pharmacology
- Neurons/drug effects
- Neurons/physiology
- Physical Stimulation
- Propylamines/pharmacology
- Rats
- Rats, Sprague-Dawley
- Receptors, Opioid, kappa/agonists
- Receptors, Opioid, kappa/antagonists & inhibitors
- Receptors, Opioid, kappa/physiology
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Affiliation(s)
- J M Gschossmann
- CURE Digestive Diseases Research Center/Neuroenteric Disease Program, Department of Medicine, University of California, Los Angeles, Los Angeles CA, USA
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Truncated apolipoprotein E (ApoE) causes increased intracellular calcium and may mediate ApoE neurotoxicity. J Neurosci 1999. [PMID: 10436064 DOI: 10.1523/jneurosci.19-16-07100.1999] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Apolipoprotein E (apoE)-related synthetic peptides, the 22 kDa N-terminal thrombin-cleavage fragment of apoE (truncated apoE), and full-length apoE have all been shown to exhibit neurotoxic activity under certain culture conditions. In the present study, protease inhibitors reduced the neurotoxicity and proteolysis of full-length apoE but did not block the toxicity of truncated apoE or a synthetic apoE peptide, suggesting that fragments of apoE may account for its toxicity. Additional experiments demonstrated that both truncated apoE and the apoE peptide elicit an increase in intracellular calcium levels and subsequent death of embryonic rat hippocampal neurons in culture. Similar effects on calcium were found when the apoE peptide was applied to chick sympathetic neurons. The rise in intracellular calcium and the hippocampal cell death caused by the apoE peptide were significantly reduced by receptor-associated protein, removal of extracellular calcium, or administration of the specific NMDA glutamate receptor antagonist MK-801. These results suggest that apoE may be a source of both neurotoxicity and calcium influx that involves cell surface receptors. Such findings strengthen the hypothesis that apoE plays a direct role in the pathology of Alzheimer's disease.
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39
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Brunetti O, Barazzoni AM, Della Torre G, Clavenzani P, Pettorossi VE, Bortolami R. Partial transformation from fast to slow muscle fibers induced by deafferentation of capsaicin-sensitive muscle afferents. Muscle Nerve 1997; 20:1404-13. [PMID: 9342157 DOI: 10.1002/(sici)1097-4598(199711)20:11<1404::aid-mus8>3.0.co;2-e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Mechanical and histochemical characteristics of the lateral gastrocnemius (LG) muscle of the rat were examined 21 days after capsaicin injection into the LG muscle. The capsaicin caused a decrease in generation rate of twitch and tetanic tension and an increase in fatigue resistance of LG muscle. The histochemical muscle fiber profile evaluated by myosin adenosine triphosphatase and reduced nicotinamide adenine dinucleotide tetrazolium reductase methods showed an increase of type I and IIC fibers and a decrease of the type IIB in whole muscle, and a decrease of the IIA, IIX fibers in the red part accompanied by their increase in the white part. Therefore the capsaicin treatment, which selectively eliminated fibers belonging to the III and IV groups of muscle afferents, induced muscle fiber transformation from fast contracting fatiguing fibers to slowly contracting nonfatiguing ones.
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Affiliation(s)
- O Brunetti
- Institute of Human Physiology, University of Perugia, Italy
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40
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Appendino G, Szallasi A. Euphorbium: modern research on its active principle, resiniferatoxin, revives an ancient medicine. Life Sci 1997; 60:681-96. [PMID: 9064473 DOI: 10.1016/s0024-3205(96)00567-x] [Citation(s) in RCA: 128] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Resiniferatoxin, an ultrapotent capsaicin analog present in the latex of Euphorbia resinifera, interacts at a specific membrane recognition site (referred to as the vanilloid receptor), expressed by primary sensory neurons mediating pain perception as well as neurogenic inflammation. Desensitization to resiniferatoxin is a promising approach to mitigate neuropathic pain and other pathological conditions in which sensory neuropeptides released from capsaicin-sensitive neurons play a crucial role. Clinical trials to evaluate the potential of topical resiniferatoxin treatment to relieve pain associated with diabetic polyneuropathy and postherpetic neuralgia are in progress. Though resiniferatoxin was isolated only two decades ago, the dried latex of Euphorbia resinifera, called Euphorbium, has been in medicinal use since the time of recorded history. This review highlights the most important events in the history of this ancient medicine, from the first written record of the therapeutic potential of Euphorbium (at the time of the reign of the Roman Emperor Augustus) to the identification of its active principle as resiniferatoxin in 1975. A brief overview of the enormous contribution of resiniferatoxin to our current understanding of the anatomical localization, function, and pharmacology of vanilloid receptors is provided. Lastly, the mechanisms are summarized by which capsaicin and resiniferatoxin, despite sharing receptors, may have dissimilar biological actions.
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Affiliation(s)
- G Appendino
- Dipartimento di Scienza e Tecnologia del Farmaco, Università degli Studi di Torino, Italy
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41
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42
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Tymianski M, Tator CH. Normal and abnormal calcium homeostasis in neurons: a basis for the pathophysiology of traumatic and ischemic central nervous system injury. Neurosurgery 1996; 38:1176-95. [PMID: 8727150 DOI: 10.1097/00006123-199606000-00028] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Clinical recovery after central nervous system (CNS) trauma or ischemia may be limited by a neural injury process that is triggered and perpetuated at the cellular level, rather than by a lesion amenable to surgical repair. It is widely thought that one such process, a fundamental pathological mechanism initiated by CNS injury, is a disruption of cellular Ca2+ homeostasis. Because of the critical role of Ca2+ ions in regulating innumerable cellular functions, this major homeostatic disturbance is thought to trigger neuronal and axonal degeneration and produce clinical disability. We review those aspects of normal and pathological Ca2+ homeostasis in neurons that relate to neurodegeneration and to the application of neuroprotective strategies for the treatment of CNS injury. In particular, we examine the contribution of Ca(2+)-permeable ionic channels, Ca2+ pumps, intracellular Ca2+ stores, intracellular Ca2+ buffering systems, and the roles of secondary, Ca(2+)-dependent processes in neurodegeneration. A number of hypotheses linking Ca2+ ions and Ca2+ permeable channels to neurotoxicity are discussed with an emphasis on strategies for lessening Ca(2+)-related damage. A number of these strategies may have a future role in the treatment of traumatic and ischemic CNS injury.
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Affiliation(s)
- M Tymianski
- Division of Neurosurgery, Toronto Hospital, Ontario, Canada
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43
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Tymianski M, Tator CH. Normal and Abnormal Calcium Homeostasis in Neurons: A Basis for the Pathophysiology of Traumatic and Ischemic Central Nervous System Injury. Neurosurgery 1996. [DOI: 10.1227/00006123-199606000-00028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
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44
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Hernádi L, Erdélyi L, Párducz A, Szabadi H, Such G, Jancsó G. In vitro capsaicin-induced cytological changes and alteration in calcium distribution in giant serotonergic neurons of the snail Helix pomatia: a light- and electron-microscopic study. Cell Tissue Res 1995; 282:445-53. [PMID: 8581938 DOI: 10.1007/bf00318876] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Morphological changes induced by capsaicin were studied in the serotonergic metacerebral giant neurons of the cerebral ganglia of Helix pomatia under in vitro conditions. Capsaicin at a concentration of 10(-4)M caused characteristic structural alterations in the giant serotonergic neurons but did not significantly influence serotonin immunoreactivity in the neurons. At the light-microscopic level, the most conspiciuous structural alterations were swelling of the cell bodies, which contained a swollen pale nucleus. Under the electron microscope, the nuclei, mitochondria and the cisternae of the endoplasmic reticulum were swollen in the capsaicin-affected metacerebral giant neurons. Electron-microscopic cytochemical techniques for calcium demonstration revealed electron-dense deposits in the swollen mitochondria and in the cisternae of the endoplasmic reticulum, suggesting an increased Ca2+ influx. The serotonergic metacerebral giant neurons could be labelled by cobalt (1mM) in the presence of capsaicin (10(-4)M) suggesting that capsaicin opens the cation chanels of the capsaicin-sensitive neuronal membrane. The morphological and cytochemical alterations induced by capsaicin in the serotonergic metacerebral giant neurons of Helix pomatia closely resemble those induced in sensory neurons of mammalian dorsal root ganglion.
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Affiliation(s)
- L Hernádi
- Balaton Limnological Research Institute of the Hungarian Academy of Sciences, Tihany, 8237 Hungary
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45
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Chard PS, Bleakman D, Savidge JR, Miller RJ. Capsaicin-induced neurotoxicity in cultured dorsal root ganglion neurons: involvement of calcium-activated proteases. Neuroscience 1995; 65:1099-108. [PMID: 7617165 DOI: 10.1016/0306-4522(94)00548-j] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We examined the mechanism by which capsaicin produces its toxic effects on cultures of rat sensory neurons. Capsaicin caused a robust increase in [Ca2+]i in a subpopulation of cultured rat dorsal root ganglion neurons. Similarly, a brief exposure to capsaicin resulted in delayed degeneration of a subpopulation of the cells. This subpopulation (about 35% of the cells present) was characterized by a capsaicin-induced uptake of Co2+, which could be detected cytochemically. Both capsaicin-induced Co2+ uptake and capsaicin-induced cell death were blocked by the capsaicin antagonist Ruthenium Red. Cell death was also prevented by removal of external calcium or by inhibiting calcium-activated proteases such as calpain. Evidence that calpain activity was increased was provided by examining the amount of degradation of the preferred calpain substrate alpha-spectrin. Capsaicin treatment produced a significant increase in the levels of the 150,000 molecular weight spectrin breakdown product. Furthermore, applying the protease inhibitors E64 or MDL 28,170 reduced capsaicin-mediated cell death. It is concluded that capsaicin kills a subpopulation of sensory neurons by activating a receptor-operated channel. The consequent Ca2+ ion influx causes large increases in [Ca2+]i and subsequent activation of Ca(2+)-sensitive proteases. This model provides support for the role of [Ca2+]i as the orchestrator of delayed neuronal degeneration.
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Affiliation(s)
- P S Chard
- Department of Pharmacological and Physiological Sciences, University of Chicago, IL 60637, USA
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46
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Electron Probe X-Ray Microanalysis as a Tool for Discerning Mechanisms of Nerve Injury. Neurotoxicology 1995. [DOI: 10.1016/b978-012168055-8/50031-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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47
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Johannessen JN. Biomolecular Approaches to Neurotoxic Hazard Assessment. Neurotoxicology 1995. [DOI: 10.1016/b978-012168055-8/50027-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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48
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Stjärne P, Lundblad L, Rinder J. Ruthenium red selectively attenuates capsaicin induced vasodilation in pig nasal mucosa. Acta Otolaryngol 1994; 114:651-6. [PMID: 7533471 DOI: 10.3109/00016489409126121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The effect of ruthenium red, a blocker of transmembrane Ca2+ fluxes, on vasodilation in pig nasal mucosa induced by capsaicin, nicotine, bradykinin or histamine was evaluated in an in vivo preparation. To decrease toxic systemic effects pretreatment with ruthenium red was performed locally, intra-arterially in a nasal artery. Pretreatment with two doses of ruthenium red was evaluated (0.25 and 2.5 mg kg-1). Ruthenium red, in the low dose, resulted in a marked attenuation of the capsaicin-induced nasal vasodilation while the effect on the nicotine-induced vasodilation was not as prominent. Pretreatment with the high dose significantly blocked the vasodilatory effects of capsaicin, nicotine, bradykinin and histamine. Our series indicates that low concentration ruthenium red selectively modulates capsaicin induced vasodilation in pig nasal mucosa in vivo, probably via a direct blocking effect on cation channels opened by capsaicin. A high concentration of ruthenium red may exert a general inhibitory effect on transmembrane Ca2+ transport.
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Affiliation(s)
- P Stjärne
- Department of Oto-Rhino-Laryngology, Karolinska Institute, Stockholm, Sweden
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49
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Ninkina NN, Willoughby JJ, Beech MM, Coote PR, Wood JN. Molecular cloning of a resiniferatoxin-binding protein. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1994; 22:39-48. [PMID: 8015392 DOI: 10.1016/0169-328x(94)90030-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Capsaicin and resiniferatoxin are neurotoxins which act on a sensory neuron membrane-associated receptor. In order to identify sensory neuron capsaicin binding proteins, expressed fusion proteins encoded by a directionally-cloned rat neonatal dorsal root ganglion library in lambda Zap-II were photoaffinity-labelled with the potent resiniferatoxin and capsaicin-like agonist resiniferanol-9,13,14-orthophenylacetate-20-(3-azido, 4-methoxyphenyl) acetate. Four clones encoding possible binding proteins were detected with rabbit anti-resiniferanotoxin antiserum and sequenced. Two clones were homologous and hybridised on Northern blots with a 1.6 kb transcript enriched in dorsal root ganglia, but also present in other non-neuronal tissues. The full-length sequence corresponding to this transcript (RTX-42) was verified using primer extension and found to encode a putative 235 amino acid protein of molecular weight 26,000 which we named RBP-26. In vitro translation of transcribed cRNA resulted in the synthesis of radiolabelled protein of the predicted molecular weight. In situ hybridisation showed that the mRNA encoding this protein was present in sensory neuron cell bodies. Both expressed bacterial fusion proteins and cytoplasmic fractions from COS cells transfected with an expression vector encoding RTX-42 showed [3H]resiniferatoxin binding activity (IC50 approximately 10 nM). RBP-26 is expressed in non-neuronal and capsaicin-insensitive neuronal tissues, and shows distinct binding characteristics from the resiniferatoxin binding site defined on DRG membranes. The functional role of RBP-26 thus remains to be established.
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Affiliation(s)
- N N Ninkina
- Sandoz Institute for Medical Research, London, UK
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50
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Szallasi A. The vanilloid (capsaicin) receptor: receptor types and species differences. GENERAL PHARMACOLOGY 1994; 25:223-43. [PMID: 8026721 DOI: 10.1016/0306-3623(94)90049-3] [Citation(s) in RCA: 151] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
1. Capsaicin was postulated to exert its pharmacological actions by interacting at a specific recognition site (receptor) expressed predominantly by primary afferent neurons. 2. The actual existence of this long-sought "capsaicin-receptor" has recently been demonstrated by the specific binding of [3H]resiniferatoxin (RTX), an ultrapotent capsaicin analog with a unique spectra of actions. 3. Since homovanillic acid is the key structural motif shared by capsaicin and RTX, their recognition site appears to be best termed the vanilloid receptor. 4. Central (sensory ganglia and spinal cord) vanilloid receptors of the rat bind RTX with high affinity in a cooperative fashion; moreover, they recognize capsaicin with higher affinity than the competp6ive antagonist, capsazepine. Peripheral (urinary bladder, urethra, airways, colon) vanilloid receptors, by contrast, bind RTX with lower affinity in a noncooperative manner. An opposite affinity for capsazepine relative to capsaicin appears to distinguish vanilloid receptors in the urinary bladder from those present in the airways or colon. These findings imply heterogeneity in the properties of vanilloid receptors. 5. The affinity of [3H]RTX binding in vitro is influenced by reducing agents, suggesting an in vivo modulatory role for endogenous reducing agents in vanilloid receptor functions. 6. The size of central vanilloid receptors (270 kDa) as measured by radiation inactivation and the cooperative binding both suggest a receptor cluster with cooperating subunits. 7. RTX binds to vanilloid receptors with orders of magnitude higher affinity than capsaicin; its ability to induce cooperative binding is also more pronounced. These differences in receptor binding along with the pharmacokinetical differences in tissue equilibration and in plasma binding may form a rational basis to explain the peculiar spectrum of actions of RTX. 8. Guinea pig spinal cord and airway membranes bind RTX with lower affinity than rat tissues. The receptor density is, however, higher in the guinea pig in keeping with the marked sensitivity of this species to vanilloid actions. 9. The apparently low level of specific [3H]RTX binding sites in the hamster and rabbit is in accord with the resistance of these species to vanilloid actions. 10. In post-mortem human spinal cord specific [3H]RTX binding sites can be detected; their binding parameters are similar to those determined in guinea pig spinal cord. 11. The vanilloid receptor appears to display both intraspecies heterogeneity and marked interspecies differences. 12. As yet, it is known whether the vanilloid receptor is operated by endogenous ligands. It is not known either which receptor superfamily (if any) it belongs to. The [3H]RTX binding assay has, however, the potential of answering these questions.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- A Szallasi
- Department of Pharmacology, Menarini Richerche Sud, Pomezia (Roma), Italy
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