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Pałasz A, Krzystanek M. Spider Neurotoxins as Modulators of NMDA Receptor Signaling. Neuromolecular Med 2021; 24:250-256. [PMID: 34562203 PMCID: PMC9402494 DOI: 10.1007/s12017-021-08692-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 09/14/2021] [Indexed: 11/26/2022]
Abstract
Molecules that selectively act on N-methyl-D-aspartate (NMDA) receptors may have a multidirectional effect by modulating the activity of NMDARs, affecting their active sites as well as by changing the composition of their subunits. The results of the clinical trials conducted so far in mood disorders and schizophrenia indicate that such agents may become new effective drugs for the treatment of these diseases. Number of spider neurotoxins e.g. ctenitoxins extracted from Phoneutria sp. venom act as potent and selective NMDAR blockers that do not disturb cortical and hippocampal glutamate signaling, LTP generation and synaptic neurochemistry. Possibly this intriguing kind of promising neuroregulatory peptides and polyamines can be clinically applicable in a wide spectrum of neuropsychiatric disorders, including epilepsy, neurotrauma and ischemic injuries. These novel medications can potentially be helpful in the future treatment of stroke and several neurodegenerative diseases.
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Affiliation(s)
- Artur Pałasz
- Department of Histology, Faculty of Medical Sciences, Medical University of Silesia, ul. Medyków 18, 40-752, Katowice, Poland.
| | - Marek Krzystanek
- Department of Psychiatry and Psychotherapy, Clinic of Psychiatric Rehabilitation, Faculty of Medical Sciences in Katowice, Medical University of Silesia, ul. Ziolowa 45/47, 40-635, Katowice, Poland
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2
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Négrel S, Brunel JM. Synthesis and Biological Activities of Naturally Functionalized Polyamines: An Overview. Curr Med Chem 2021; 28:3406-3448. [PMID: 33138746 DOI: 10.2174/0929867327666201102114544] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 09/01/2020] [Accepted: 09/16/2020] [Indexed: 11/22/2022]
Abstract
Recently, extensive researches have emphasized the fact that polyamine conjugates are becoming important in all biological and medicinal fields. In this review, we will focus our attention on natural polyamines and highlight recent progress in both fundamental mechanism studies and interests in the development and application for the therapeutic use of polyamine derivatives.
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Affiliation(s)
- Sophie Négrel
- Aix Marseille University, Faculty of Pharmacy, UMR-MD1, 27 bd Jean Moulin, 13385 Marseille, France
| | - Jean Michel Brunel
- Aix Marseille University, Faculty of Pharmacy, UMR-MD1, 27 bd Jean Moulin, 13385 Marseille, France
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3
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Affiliation(s)
- Olena Filchakova
- Department of Biology, School of Science and Technology, Nazarbayev University, Astana, Republic of Kazakhstan
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4
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Monge-Fuentes V, Gomes FMM, Campos GAA, Silva JDC, Biolchi AM, Dos Anjos LC, Gonçalves JC, Lopes KS, Mortari MR. Neuroactive compounds obtained from arthropod venoms as new therapeutic platforms for the treatment of neurological disorders. J Venom Anim Toxins Incl Trop Dis 2015; 21:31. [PMID: 26257776 PMCID: PMC4529710 DOI: 10.1186/s40409-015-0031-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 07/28/2015] [Indexed: 01/25/2023] Open
Abstract
The impact of neurological disorders in society is growing with alarming estimations for an incidence increase in the next decades. These disorders are generally chronic and can affect individuals early during productive life, imposing real limitations on the performance of their social roles. Patients can have their independence, autonomy, freedom, self-image, and self-confidence affected. In spite of their availability, drugs for the treatment of these disorders are commonly associated with side effects, which can vary in frequency and severity. Currently, no effective cure is known. Nowadays, the biopharmaceutical research community widely recognizes arthropod venoms as a rich source of bioactive compounds, providing a plethora of possibilities for the discovery of new neuroactive compounds, opening up novel and attractive opportunities in this field. Several identified molecules with a neuropharmacological profile can act in the central nervous system on different neuronal targets, rendering them useful tools for the study of neurological disorders. In this context, this review aims to describe the current main compounds extracted from arthropod venoms for the treatment of five major existing neurological disorders: stroke, Alzheimer’s disease, epilepsy, Parkinson’s disease, and pathological anxiety.
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Affiliation(s)
- Victoria Monge-Fuentes
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Flávia Maria Medeiros Gomes
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Gabriel Avohay Alves Campos
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Juliana de Castro Silva
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Andréia Mayer Biolchi
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Lilian Carneiro Dos Anjos
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Jacqueline Coimbra Gonçalves
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Kamila Soares Lopes
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
| | - Márcia Renata Mortari
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF CEP 70.910-900, Brasília, Brazil
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5
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Common Binding Site for Externally and Internally Applied AMPA Receptor Channel Blockers. J Mol Neurosci 2009; 39:169-74. [DOI: 10.1007/s12031-008-9172-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2008] [Accepted: 12/18/2008] [Indexed: 10/21/2022]
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6
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Lodge D. The history of the pharmacology and cloning of ionotropic glutamate receptors and the development of idiosyncratic nomenclature. Neuropharmacology 2008; 56:6-21. [PMID: 18765242 DOI: 10.1016/j.neuropharm.2008.08.006] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2008] [Revised: 07/31/2008] [Accepted: 08/06/2008] [Indexed: 10/21/2022]
Abstract
In this article, the beginnings of glutamate pharmacology are traced from the early doubts about 'non-specific' excitatory effects, through glutamate- and aspartate-preferring receptors, to NMDA, quisqualate/AMPA and kainate subtypes, and finally to the cloning of genes for these receptor subunits. The development of selective antagonists, crucial to the subtype classification, allowed the fundamental importance of glutamate receptors to synaptic activity throughout the CNS to be realised. The ability to be able to express and manipulate cloned receptor subunits is leading to huge advances in our understanding of these receptors. Similarly the tortuous path of the nomenclature is followed from naming with reference to exogenous agonists, through abortive early attempts at generic schemes, and back to the NC-IUPHAR system based on the natural agonist, the defining exogenous agonist and the gene names.
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Affiliation(s)
- David Lodge
- MRC Centre for Synaptic Plasticity, Department of Anatomy, University of Bristol, University Walk, Bristol BS8 1TD, United Kingdom.
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7
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Mortari MR, Cunha AOS, Ferreira LB, dos Santos WF. Neurotoxins from invertebrates as anticonvulsants: From basic research to therapeutic application. Pharmacol Ther 2007; 114:171-83. [PMID: 17399793 DOI: 10.1016/j.pharmthera.2007.01.009] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2007] [Revised: 01/19/2007] [Accepted: 01/19/2007] [Indexed: 12/21/2022]
Abstract
Invertebrate venoms have attracted considerable interest as a potential source of bioactive substances, especially neurotoxins. These molecules have proved to be extremely useful tools for the understanding of synaptic transmission events, and they have contributed to the design of novel drugs for the treatment of neurological disorders and pain. In this context, as epilepsy involves neuronal substrates, which are sites of action of many neurotoxins; venoms may be particularly useful for antiepileptic drug (AED) research. Epilepsy is a chronic disease whose treatment consists of controlling seizures with antiepileptics that very often induce strong undesirable side effects that may limit treatment. Here, we review the vast, but yet unexplored, world of neurotoxins from invertebrates used as probes in pharmacological screening for novel and less toxic antiepileptics. We briefly review (1) the molecular basis of epilepsy, as well as the sites of action of commonly used anticonvulsants (we bring a comprehensive review of the elements from invertebrate venoms which are mostly studied in neuroscience research and may be useful for drug development); (2) peptides from conus snails; (3) peptides and polyamine toxins from spiders and wasps; and (4) peptides from scorpions.
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Affiliation(s)
- Márcia Renata Mortari
- Neurobiology and Venoms Laboratory, Department of Biology, School of Philosophy, Sciences and Literature, University of São Paulo Ribeirão Preto, Brazil
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8
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Pogatzki-Zahn EM, Niemeier JS, Sorkin LS, Brennan TJ. Spinale Glutamatrezeptorantagonisten: Differenzierung von primärer und sekundärer mechanischer Hyperalgesie nach operativer Schnittinzision im Tierexperiment. Schmerz 2006; 20:245-53. [PMID: 16763860 DOI: 10.1007/s00482-006-0481-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Secondary mechanical hyperalgesia has been demonstrated in postoperative patients indicating that central sensitization occurs after surgery. However, the underlying mechanisms are unknown. Here, we studied the role of spinal AMPA/kainate receptors for pain behaviors indicating secondary hyperalgesia caused by gastrocnemius incision in the rat. These were reduced by NBQX, a selective antagonist of AMPA/kainate receptors. However, administration of NMDA receptor antagonists caused no or only a modest decrease in behaviors for secondary hyperalgesia but produced associated motor deficits and supraspinal side effects. We further determined that only secondary mechanical hyperalgesia was reversed by JSTX, a selective antagonist of calcium-permeable AMPA receptor; primary mechanical hyperalgesia and guarding behavior were unchanged. These findings indicate that JSTX influenced a spinal amplification process that leads to secondary hyperalgesia but does not contribute to primary hyperalgesia and guarding after incision. This amplification process likely requires Ca(2) influx through spinal AMPA/KA (but not NMDA) receptors. Behaviors for secondary mechanical hyperalgesia after incision can be inhibited without affecting primary mechanical hyperalgesia and guarding. Mechanisms for central sensitization causing secondary hyperalgesia in postoperative patients may therefore be separated from spontaneous pain and hyperalgesia that arises adjacent to the area of the incision.
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MESH Headings
- Animals
- Calcium/metabolism
- Excitatory Amino Acid Antagonists/pharmacology
- Hyperalgesia/physiopathology
- Male
- Mechanoreceptors/drug effects
- Mechanoreceptors/physiopathology
- Muscle, Skeletal/innervation
- Muscle, Skeletal/surgery
- Neurotoxins/pharmacology
- Pain Threshold/drug effects
- Pain Threshold/physiology
- Pain, Postoperative/physiopathology
- Quinoxalines/pharmacology
- Rats
- Rats, Sprague-Dawley
- Receptors, AMPA/antagonists & inhibitors
- Receptors, AMPA/physiology
- Receptors, Glutamate/drug effects
- Receptors, Glutamate/physiology
- Receptors, Kainic Acid/antagonists & inhibitors
- Receptors, Kainic Acid/physiology
- Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors
- Receptors, N-Methyl-D-Aspartate/physiology
- Spider Venoms/pharmacology
- Spinal Cord/drug effects
- Spinal Cord/physiopathology
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Affiliation(s)
- E M Pogatzki-Zahn
- Klinik und Poliklinik für Anästhesiologie und operative Intensivmedizin, Westfälische Wilhelms-Universität, 48129 Münster.
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9
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Abstract
Neurodegeneration induced by excitatory neurotransmitter glutamate is considered to be of particular relevance in several types of acute and chronic neurological impairments ranging from cerebral ischaemia to neuropathological conditions such as motor neuron disease, Alzheimer's, Parkinson's disease and epilepsy. The hyperexcitation of glutamate receptors coupled with calcium overload can be prevented or modulated by using well-established competitive and non-competitive antagonists targeting ion/receptor channels. The exponentially increasing body of pharmacological evidence over the years indicates potential applications of peptide toxins, due to their exquisite subtype selectivity on ion channels and receptors, as lead structures for the development of drugs for the treatment of wide variety of neurological disorders. This review comprehensively highlights the overview of the diversity in the molecular as well as neurobiological mechanisms of different peptide toxins derived from venomous animals with particular reference to neuroprotection. In addition, the potential applications of peptide toxins in the diagnosis and treatment of neurological disorders such as neuromuscular disorders, epilepsy, Alzheimer's and Parkinson's diseases, gliomas and ischaemic stroke and their future prospects in the diagnosis as well as in the therapy are addressed.
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Affiliation(s)
- Wudayagiri Rajendra
- Department of Biochemistry, Faculty of Medicine, National University of Singapore, 8 Medical Drive, Singapore 117597, Singapore
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10
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Rajendra W, Armugam A, Jeyaseelan K. Toxins in anti-nociception and anti-inflammation. Toxicon 2004; 44:1-17. [PMID: 15225557 DOI: 10.1016/j.toxicon.2004.04.014] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2003] [Revised: 04/05/2004] [Accepted: 04/08/2004] [Indexed: 10/26/2022]
Abstract
The use of toxins as novel molecular probes to study the structure-function relationship of ion-channels and receptors as well as potential therapeutics in the treatment of wide variety of diseases is well documented. The high specificity and selectivity of these toxins have attracted a great deal of interest as candidates for drug development. This review highlights the involvement of the proteins and peptide toxins as well as non-proteinaceous compounds derived from both venomous and non-venomous animals, in anti-nociception and anti-inflammation. The possible mechanisms of these potential therapeutic agents and possible clinical applications in the treatment of pain and inflammation are also summarized.
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Affiliation(s)
- Wudayagiri Rajendra
- Department of Biochemistry, Faculty of Medicine, National University of Singapore, 8, Medical Drive, Singapore, Singapore 117597
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11
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Strømgaard K, Mellor I. AMPA receptor ligands: Synthetic and pharmacological studies of polyamines and polyamine toxins. Med Res Rev 2004; 24:589-620. [PMID: 15224382 DOI: 10.1002/med.20004] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors (AMPAR), subtype of the ionotropic glutamate receptors (IGRs), mediate fast synaptic transmission in the central nervous system (CNS), and are involved in many neurological disorders, as well as being a key player in the formation of memory. Hence, ligands affecting AMPARs are highly important for the study of the structure and function of this receptor, and in this regard polyamine-based ligands, particularly polyamine toxins, are unique as they selectively block Ca2+ -permeable AMPARs. Indeed, endogenous intracellular polyamines are known to modulate the function of these receptors in vivo. In this study, recent developments in the medicinal chemistry of polyamine-based ligands are given, particularly focusing on the use of solid-phase synthesis (SPS) as a tool for the facile generation of libraries of polyamine toxin analogues. Moreover, the recent development of highly potent and very selective AMPAR ligands is described. Additionally, we provide a detailed account on the mechanism and site of action of AMPAR blockade by polyamine-based ligands, including examples of how these ligands are used as tools to study AMPAR, and a comparison with their action on other ionotropic receptors.
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Affiliation(s)
- Kristian Strømgaard
- Department of Medicinal Chemistry, The Danish University of Pharmaceutical Sciences, Universitetsparken 2, DK-2100 Copenhagen.
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12
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Abstract
This review summarises current knowledge of polyamine-containing spider toxins and their interactions with ionotropic receptors of invertebrate and vertebrate excitable cells. Their diverse actions on ionotropic glutamate and acetylcholine receptors, which include potentiation, closed channel block and open channel block, are discussed in the context of toxin and target structures. Factors that complicate attempts to identify and pharmacologically characterise the binding sites for these toxins include their ability to permeate channels of some ionotropic receptors and their apparent accumulation in a cellular compartment, possibly the membrane bilayer.
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Affiliation(s)
- Ian R Mellor
- School of Biology, University of Nottingham, University Park, Nottingham NG7 2RD, UK
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13
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Pogatzki EM, Niemeier JS, Sorkin LS, Brennan TJ. Spinal glutamate receptor antagonists differentiate primary and secondary mechanical hyperalgesia caused by incision. Pain 2003; 105:97-107. [PMID: 14499425 DOI: 10.1016/s0304-3959(03)00169-6] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Secondary mechanical hyperalgesia has been demonstrated in postoperative patients indicating that central sensitization occurs after surgery. However, the underlying mechanisms are unknown. Here, we studied the role of spinal N-methyl-D-aspartate and alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA)/kainate receptors for pain behaviors indicating secondary hyperalgesia caused by gastrocnemius incision in the rat. We further determined if Ca(2+) permeable AMPA/kainate receptors are important for secondary hyperalgesia after gastrocnemius incision and for pain behaviors indicating primary hyperalgesia and guarding behavior after plantar incision. Withdrawal thresholds (WTs) to punctate mechanical stimuli were assessed by applying calibrated monofilaments to the plantar hind paw before gastrocnemius incision. WTs were tested again 2 h after gastrocnemius incision and again after intrathecal (IT) injection of either dizocilpine maleate (MK-801), 2-amino-5-phosphonovaleric acid (AP5), 1,2,3,4-tetrahydro-6-nitro-2,3-dioxo[f]quinoxaline-7-sulfonamide (NBQX), or Joro spider toxin (JSTX). The doses used were: MK-801 (vehicle, 15, 30, 40 nmol), AP5 (vehicle, 10, 30 nmol), NBQX (vehicle, 5, 10 nmol), and JSTX (vehicle, 2, 5, 9 nmol). In the same rats, WTs were tested on postoperative day 2 before and after the same drugs were injected again. In other rats, WTs to monofilaments and response frequencies to a non-punctate mechanical stimulus or guarding behaviors were determined before, 1 h after plantar incision was made, and assessed again after JSTX (9 nmol or vehicle) was administered IT. Secondary mechanical hyperalgesia after gastrocnemius incision was dose-dependently blocked by NBQX but was only marginally affected by AP5 or MK-801. Only secondary mechanical hyperalgesia was reversed by JSTX; primary mechanical hyperalgesia and guarding behavior were unchanged. These results indicate that spinal sensitization contributing to behaviors for secondary hyperalgesia after incision requires Ca(2+) permeable AMPA/kainate receptors. The data further demonstrate that behaviors for secondary mechanical hyperalgesia after incision can be inhibited without affecting behaviors for primary mechanical hyperalgesia and guarding. Mechanisms for central sensitization causing secondary hyperalgesia in postoperative patients may therefore be separated from spontaneous pain and hyperalgesia that arises adjacent to the area of the incision.
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Affiliation(s)
- Esther M Pogatzki
- Department of Anesthesia, University of Iowa, 200 Hawkins Drive 6 JCP, Iowa City, IA 52242, USA
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14
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Albensi BC, Alasti N, Mueller AL. Long-term potentiation in the presence of NMDA receptor antagonist arylalkylamine spider toxins. J Neurosci Res 2000; 62:177-85. [PMID: 11020211 DOI: 10.1002/1097-4547(20001015)62:2<177::aid-jnr3>3.0.co;2-d] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The role of the NMDA receptor (NMDAR) in long-term potentiation (LTP) is now well established. All potent NMDAR antagonists known to date inhibit the induction of LTP at the Schaffer collateral-CA1 pyramidal cell synapse in rat hippocampus, regardless of their site and mechanism of action. Arylalkylamine toxins are noncompetitive NMDAR antagonists in the mammalian central nervous system (CNS). The synthetic toxins argiotoxin-636 (Arg-636), Joro spider toxin (JSTX-3), alpha-agatoxin-489 and -505 (Agel-489 and Agel-505) and philanthotoxin-433 (delta-PhTX) were found in the present study to have no effect on the induction of LTP in the Schaffer collateral-CA1 pyramidal cell pathway in rat hippocampal slices maintained in vitro. Arylalkylamine toxins represent a class of potent NMDAR antagonists that fail to affect hippocampal LTP, and thus provide novel structural leads for the development of NMDAR antagonists that do not impair cognition.
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Affiliation(s)
- B C Albensi
- NPS Pharmaceuticals, Inc., Salt Lake City, Utah 84108, USA
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15
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Stanfa LC, Hampton DW, Dickenson AH. Role of Ca2+-permeable non-NMDA glutamate receptors in spinal nociceptive transmission. Neuroreport 2000; 11:3199-202. [PMID: 11043548 DOI: 10.1097/00001756-200009280-00030] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The functional role of Ca2+-permeable non-NMDA receptors in spinal nociceptive processing was investigated using joro spider toxin (JSTx), a selective blocker of these receptors. JSTx 0.25 and 1 microg administered spinally produced a significant facilitation of the C-fibre evoked response and post-discharge, but not the A-fibre response, of dorsal horn neurones recorded in adult rats. This may result from a block of Ca2+-permeable AMPA receptors located on GABAergic interneurones. At higher doses, this facilitation of responses was lost, suggesting additional Ca2+-permeable non-NMDA receptors, possibly kainate receptors, in excitatory spinal pathways. Thus, functional Ca2+-permeable AMPA receptors are present within the dorsal horn, predominantly within inhibitory pathways, and play a role distinct from other excitatory amino acid receptors in spinal nociceptive processing.
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Affiliation(s)
- L C Stanfa
- Department of Pharmacology, University College London, UK
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16
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Pizzo AB, Fontana AC, Coutinho-Netto J, dos Santos WF. Effects of the crude venom of the social wasp Agelaia vicina on gamma-aminobutyric acid and glutamate uptake in synaptosomes from rat cerebral cortex. J Biochem Mol Toxicol 2000; 14:88-94. [PMID: 10630422 DOI: 10.1002/(sici)1099-0461(2000)14:2<88::aid-jbt4>3.0.co;2-g] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Glutamate (L-glu) is the most important excitatory neurotransmitter in the mammalian central nervous system. Its action is terminated by transporters located in the plasma membrane of neurons and glial cells, which have a critical role in preventing glutamate excitotoxicity under normal conditions. The neurotransmitter gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the mammalian central nervous system. Venoms of solitary wasps and orb-spiders are composed of large proteins, medium-size peptides, polyamine amides (PAs), and other neuroactive components that are highly selective to nervous tissues. The abnormal operation of uptake systems is involved in several failures. Several studies indicate alterations in extracellular GABA and glutamate concentrations in epilepsy conditions that may relate to transporter functions. The effects of the crude and boiled venom of the social wasp Agelaia vicina, "cassununga," on GABA and L-glu uptake in rat cerebral cortex synaptosomes are related. The venom uncompetitively inhibited high- and low-affinity GABA uptake by 91.2% and by 76%, respectively. This kind of inhibition was also found to affect high- (99.6%) and low-affinity (90%) uptake of L-glu. These results suggest that the effects observed in these experiments indicate the venom of A. vicina to be a useful tool to further characterize GABA- and L-glu-uptake systems.
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Affiliation(s)
- A B Pizzo
- Department of Biology, Faculty of Philosophy, Sciences, and Letters, University of São Paulo, Ribeirão Preto, Brazil
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17
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Affiliation(s)
- D Bleakman
- Lilly Research Laboratories, Eli Lilly & Company, Lilly Corporate Center, Indianapolis, IN 46285, USA.
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18
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Green AC, Nakanishi K, Usherwood PN. Polyamine amides are neuroprotective in cerebellar granule cell cultures challenged with excitatory amino acids. Brain Res 1996; 717:135-46. [PMID: 8738263 DOI: 10.1016/0006-8993(96)00042-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Primary cultures of rat cerebellar granule cells have been used to assess the potential neuroprotective effects of philanthotoxins and argiotoxin-636 (ArgTX-636). These polyamine amides are potent antagonists of ionotropic L-glutamate (L-Glu) receptors. In granule cells loaded with fluo-3, ArgTX-636 and philanthotoxin-343 (PhTX-343) antagonised increases of intracellular free calcium concentration ([Ca2+]i) that were stimulated by N-methyl-D-aspartate (NMDA). The antagonism was use-dependent. Antagonism by PhTX-343 was fully reversible, but recovery following antagonism by ArgTX-636 was slow and only partial during the time-course of an experiment. Neither compound inhibited K(+)-induced increases in [Ca2+]i. In excitotoxicity studies with cerebellar granule cells, the release of lactate dehydrogenase (LDH) and morphological observations were used to assess cell death. A 20-30 min exposure to 500 microM NMDA, 100 microM L-Glu or 500 microM kainate was sufficient to kill > 90% of the cells after 18-20 h. When added 5 min prior to, and during agonist exposure, PhTX-343 and ArgTX-636 provided total neuroprotection. ArgTX-636 was about 20-30 fold more potent than PhTX-343 against NMDA, but was approximately equipotent with PhTX-343 against a kainate challenge. Neither of the toxins showed any inherent toxicity even at 400 microM and 100 microM respectively. Some analogues of PhTX-343 are more potent, both in terms of antagonism of NMDA-stimulated increases of [Ca2+]i and neuroprotection, than PhTX-343 and ArgTX-636.
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Affiliation(s)
- A C Green
- Department of Life Science, University of Nottingham, University Park, UK
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19
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Fletcher EJ, Lodge D. New developments in the molecular pharmacology of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate and kainate receptors. Pharmacol Ther 1996; 70:65-89. [PMID: 8804111 DOI: 10.1016/0163-7258(96)00014-9] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Separation of non-N-methyl-D-aspartate subtypes of glutamate receptors, known as alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) and kainate receptors, is traced through conventional pharmacology to molecular biology. The physiology and pharmacology of recombinant receptor subtypes (GluR1-7 and KA1-2) are described. Competitive antagonists, e.g., the quinoxalinedione, 2,3-dihyroxy-6-nitro-7-sulphamoyl-benz(F)quinoxaline, and the decahydroisoquinoline, 3S,4aR,6R, 8aR-6-[2-(1(2)H-tetrazol-5-yl)ethyl]-decahydroisoquinolin e-3-carboxylate, have a broad antagonist spectrum, except that the latter is inactive on GluR6. The 2,3-benzodiazepines noncompetitively antagonise the AMPA receptor GluR1-4. Desensitisation of AMPA (GluR1-4) and kainate (GluR5-7 and KA1-2) receptors is blocked by cyclothiazide and concanavalin A, respectively. Polyamine toxins block AMPA receptors not containing GluR2 and unedited kainate receptors (GluR5-6). These data correlate well with results on native neurons characterised by techniques such as in situ hybridisation.
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Affiliation(s)
- E J Fletcher
- MRC Laboratory of Molecular Biology/Department of Zoology, Cambridge, UK
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Karst H, Joëls M, Wadman WJ, Piek T. Philanthotoxin inhibits Ca2+ currents in rat hippocampal CA1 neurons. Eur J Pharmacol 1994; 270:357-60. [PMID: 7805785 DOI: 10.1016/0926-6917(94)90012-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The wasp venom philanthotoxin-4.3.3 (PhTX-4.3.3) is an antagonist of glutamate transmission in the insect as well as in the mammalian brain. It was recently shown that PhTX-4.3.3 inhibits the N-methyl-D-aspartate (NMDA) transmission in rat hippocampus. In this study we show that dideaza-philanthotoxin-12 (dideaza-PhTX-12), an analogue of PhTX-4.3.3, is a potent antagonist of voltage-dependent Ca2+ currents in rat hippocampal CA1 neurons. At a concentration of 10 microM it reduces the Ca2+ current to 40%. Two voltage-dependent potassium currents, the A current and the delayed rectifier, were hardly affected by dideaza-PhTX-12, indicating selectivity of the drug for Ca2+ currents. As a consequence the philanthotoxins will inhibit the calcium influx via voltage dependent as well as NMDA mediaded calcium channels and thus reduce excitability in the hippocampus.
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Affiliation(s)
- H Karst
- Department of Experimental Zoology, University of Amsterdam, Netherlands
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Fedorov NB, Screbitsky VG, Reymann KG. Effects of philanthotoxin-343 on CA1 pyramidal neurons of rat hippocampus in vitro. Eur J Pharmacol 1992; 228:201-6. [PMID: 1282467 DOI: 10.1016/0926-6917(92)90030-g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A synthetic analog of philanthotoxin-433, philanthotoxin-343 (PhTX-343), was tested in hippocampal pyramidal neurons in vitro. PhTX-343 (2 microM) did not significantly change synaptic transmission mediated by AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid)/kainate receptors in the CA1 region of hippocampus. However, PhTX-343 significantly suppressed both the synaptic N-methyl-D-aspartate receptor-induced current (NMDA) obtained in the presence of CNQX(6-cyano-7-nitroquinoxaline-2,3-dione)/picrotoxin (10 microM) and the directly evoked NMDA receptor-induced current to pressure ejection of NMDA in the presence of tetrodotoxin (0.5 microM). A short transient facilitation of both types of NMDA response was seen immediately after the beginning of PhTX-343 application. Our results suggest that at high concentration (2 microM) PhTX-343 inhibits the NMDA-gated current, while the early facilitation occurred during an initial low concentration of the compound. Both facilitative and depressive actions of PhTX-343 are localized at the postsynaptic membrane.
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Affiliation(s)
- N B Fedorov
- Institute for Neurobiology, Magdeburg, Germany
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