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Mendes LC, Viana GMM, Nencioni ALA, Pimenta DC, Beraldo-Neto E. Scorpion Peptides and Ion Channels: An Insightful Review of Mechanisms and Drug Development. Toxins (Basel) 2023; 15:238. [PMID: 37104176 PMCID: PMC10145618 DOI: 10.3390/toxins15040238] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 03/21/2023] [Accepted: 03/22/2023] [Indexed: 04/28/2023] Open
Abstract
The Buthidae family of scorpions consists of arthropods with significant medical relevance, as their venom contains a diverse range of biomolecules, including neurotoxins that selectively target ion channels in cell membranes. These ion channels play a crucial role in regulating physiological processes, and any disturbance in their activity can result in channelopathies, which can lead to various diseases such as autoimmune, cardiovascular, immunological, neurological, and neoplastic conditions. Given the importance of ion channels, scorpion peptides represent a valuable resource for developing drugs with targeted specificity for these channels. This review provides a comprehensive overview of the structure and classification of ion channels, the action of scorpion toxins on these channels, and potential avenues for future research. Overall, this review highlights the significance of scorpion venom as a promising source for discovering novel drugs with therapeutic potential for treating channelopathies.
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Affiliation(s)
- Lais Campelo Mendes
- Programa de Pós-Graduação em Ciências—Toxinologia do Instituto Butantan, São Paulo 05503-900, Brazil
- Laboratório de Bioquímica do Instituto Butantan, São Paulo 05503-900, Brazil
| | | | | | | | - Emidio Beraldo-Neto
- Laboratório de Bioquímica do Instituto Butantan, São Paulo 05503-900, Brazil
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2
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Lazcano-Pérez F, Bermeo K, Castro H, Salazar Campos Z, Arenas I, Zavala-Moreno A, Chávez-Villela SN, Jiménez I, Arreguín-Espinosa R, Fierro R, González-Márquez H, Garcia DE, Sánchez-Rodríguez J. A Sea Anemone Lebrunia neglecta Venom Fraction Decreases Boar Sperm Cells Capacitation: Possible Involvement of HVA Calcium Channels. Toxins (Basel) 2022; 14:toxins14040261. [PMID: 35448870 PMCID: PMC9030620 DOI: 10.3390/toxins14040261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 03/30/2022] [Accepted: 04/01/2022] [Indexed: 02/04/2023] Open
Abstract
Sea anemones produce venoms characterized by a complex mixture of low molecular weight compounds, proteins and peptides acting on voltage-gated ion channels. Mammal sperm cells, like neurons, are characterized by their ion channels. Calcium channels seem to be implicated in pivotal roles such as motility and capacitation. In this study, we evaluated the effect of a low molecular weight fraction from the venom of the sea anemone Lebrunia neglecta on boar sperm cells and in HVA calcium channels from rat chromaffin cells. Spermatozoa viability seemed unaffected by the fraction whereas motility and sperm capacitation were notoriously impaired. The sea anemone fraction inhibited the HVA calcium current with partial recovery and no changes in chromaffin cells’ current kinetics and current–voltage relationship. These findings might be relevant to the pharmacological characterization of cnidarian venoms and toxins on voltage-gated calcium channels.
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Affiliation(s)
- Fernando Lazcano-Pérez
- Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Quintana Roo 77580, Mexico; (F.L.-P.); (S.N.C.-V.)
| | - Karina Bermeo
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de Mexico 04510, Mexico; (K.B.); (H.C.); (I.A.); (D.E.G.)
| | - Héctor Castro
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de Mexico 04510, Mexico; (K.B.); (H.C.); (I.A.); (D.E.G.)
| | - Zayil Salazar Campos
- Facultad de Ingeniería, Universidad Nacional Autónoma de México, Ciudad de Mexico 04510, Mexico;
- Departamento de Ciencias de la Salud, Div. C.B.S., Universidad Autónoma Metropolitana-Iztapalapa, Ciudad de Mexico 09310, Mexico; (I.J.); (R.F.); (H.G.-M.)
| | - Isabel Arenas
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de Mexico 04510, Mexico; (K.B.); (H.C.); (I.A.); (D.E.G.)
| | - Ariana Zavala-Moreno
- Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad de Mexico 04510, Mexico;
| | - Sheila Narayán Chávez-Villela
- Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Quintana Roo 77580, Mexico; (F.L.-P.); (S.N.C.-V.)
| | - Irma Jiménez
- Departamento de Ciencias de la Salud, Div. C.B.S., Universidad Autónoma Metropolitana-Iztapalapa, Ciudad de Mexico 09310, Mexico; (I.J.); (R.F.); (H.G.-M.)
| | - Roberto Arreguín-Espinosa
- Departamento de Química de Biomacromoléculas, Instituto de Química, Universidad Nacional Autónoma de México, Ciudad de Mexico 04510, Mexico;
| | - Reyna Fierro
- Departamento de Ciencias de la Salud, Div. C.B.S., Universidad Autónoma Metropolitana-Iztapalapa, Ciudad de Mexico 09310, Mexico; (I.J.); (R.F.); (H.G.-M.)
| | - Humberto González-Márquez
- Departamento de Ciencias de la Salud, Div. C.B.S., Universidad Autónoma Metropolitana-Iztapalapa, Ciudad de Mexico 09310, Mexico; (I.J.); (R.F.); (H.G.-M.)
| | - David E. Garcia
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de Mexico 04510, Mexico; (K.B.); (H.C.); (I.A.); (D.E.G.)
| | - Judith Sánchez-Rodríguez
- Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Quintana Roo 77580, Mexico; (F.L.-P.); (S.N.C.-V.)
- Correspondence: ; Tel.: +52(998)8710009
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Wang D, Ragnarsson L, Lewis RJ. T-type Calcium Channels in Health and Disease. Curr Med Chem 2018; 27:3098-3122. [PMID: 30277145 DOI: 10.2174/0929867325666181001112821] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 08/28/2018] [Accepted: 08/30/2018] [Indexed: 12/12/2022]
Abstract
Low Voltage-Activated (LVA) T-type calcium channels are characterized by transient current and Low Threshold Spikes (LTS) that trigger neuronal firing and oscillatory behavior. Combined with their preferential localization in dendrites and their specific "window current", T-type calcium channels are considered to be key players in signal amplification and synaptic integration. Assisted by the emerging pharmacological tools, the structural determinants of channel gating and kinetics, as well as novel physiological and pathological functions of T-type calcium channels, are being uncovered. In this review, we provide an overview of structural determinants in T-type calcium channels, their involvement in disorders and diseases, the development of novel channel modulators, as well as Structure-Activity Relationship (SAR) studies that lead to rational drug design.
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Affiliation(s)
- Dan Wang
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, the University of Queensland, Brisbane Qld 4072, Australia
| | - Lotten Ragnarsson
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, the University of Queensland, Brisbane Qld 4072, Australia
| | - Richard J Lewis
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, the University of Queensland, Brisbane Qld 4072, Australia
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Romero-Gutierrez T, Peguero-Sanchez E, Cevallos MA, Batista CVF, Ortiz E, Possani LD. A Deeper Examination of Thorellius atrox Scorpion Venom Components with Omic Techonologies. Toxins (Basel) 2017; 9:E399. [PMID: 29231872 PMCID: PMC5744119 DOI: 10.3390/toxins9120399] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 12/07/2017] [Accepted: 12/08/2017] [Indexed: 02/02/2023] Open
Abstract
This communication reports a further examination of venom gland transcripts and venom composition of the Mexican scorpion Thorellius atrox using RNA-seq and tandem mass spectrometry. The RNA-seq, which was performed with the Illumina protocol, yielded more than 20,000 assembled transcripts. Following a database search and annotation strategy, 160 transcripts were identified, potentially coding for venom components. A novel sequence was identified that potentially codes for a peptide with similarity to spider ω-agatoxins, which act on voltage-gated calcium channels, not known before to exist in scorpion venoms. Analogous transcripts were found in other scorpion species. They could represent members of a new scorpion toxin family, here named omegascorpins. The mass fingerprint by LC-MS identified 135 individual venom components, five of which matched with the theoretical masses of putative peptides translated from the transcriptome. The LC-MS/MS de novo sequencing allowed to reconstruct and identify 42 proteins encoded by assembled transcripts, thus validating the transcriptome analysis. Earlier studies conducted with this scorpion venom permitted the identification of only twenty putative venom components. The present work performed with more powerful and modern omic technologies demonstrates the capacity of accomplishing a deeper characterization of scorpion venom components and the identification of novel molecules with potential applications in biomedicine and the study of ion channel physiology.
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Affiliation(s)
- Teresa Romero-Gutierrez
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Avenida Universidad 2001, Apartado Postal 510-3, Cuernavaca CP: 62210, Morelos, Mexico.
| | - Esteban Peguero-Sanchez
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Avenida Universidad 2001, Apartado Postal 510-3, Cuernavaca CP: 62210, Morelos, Mexico.
| | - Miguel A Cevallos
- Programa de Genómica Evolutiva, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Apartado Postal 510-3, Cuernavaca CP: 62210, Morelos, Mexico.
| | - Cesar V F Batista
- Laboratorio Universitario de Proteómica, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Avenida Universidad 2001, Apartado Postal 510-3, Cuernavaca CP: 62210, Morelos, Mexico.
| | - Ernesto Ortiz
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Avenida Universidad 2001, Apartado Postal 510-3, Cuernavaca CP: 62210, Morelos, Mexico.
| | - Lourival D Possani
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Avenida Universidad 2001, Apartado Postal 510-3, Cuernavaca CP: 62210, Morelos, Mexico.
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5
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Wang X, Gao B, Zhu S. A single-point mutation enhances dual functionality of a scorpion toxin. Comp Biochem Physiol C Toxicol Pharmacol 2016; 179:72-8. [PMID: 26358403 DOI: 10.1016/j.cbpc.2015.09.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 08/24/2015] [Accepted: 09/01/2015] [Indexed: 12/11/2022]
Abstract
Scorpion venom represents a tremendous, hitherto partially explored peptide library that has been proven to be useful not only for understanding ion channels but also for drug design. MeuTXKα3 is a functionally unknown scorpion toxin-like peptide. Here we describe new transcripts of this gene arising from alternative polyadenylation and its biological function as well as a mutant with a single-point substitution at site 30. Native-like MeuTXKα3 and its mutant were produced in Escherichia coli and their toxic function against Drosophila Shaker K(+) channel and its mammalian counterparts (rKv1.1-rKv1.3) were assayed by two-electrode voltage clamp technique. The results show that MeuTXKα3 is a weak toxin with a wide-spectrum of activity on both Drosophila and mammalian K(+) channels. The substitution of a proline at site 30 by an asparagine, an evolutionarily conserved functional residue in the scorpion α-KTx family, led to an increased activity on rKv1.2 and rKv1.3 but a decreased activity on the Shaker channel without changing the potency on rKv1.1, suggesting a key role of this site in species selectivity of scorpion toxins. MeuTXKα3 was also active on a variety of bacteria with lethal concentrations ranging from 4.66 to 52.01μM and the mutant even had stronger activity on some of these bacterial species. To the best of our knowledge, this is the first report on a bi-functional short-chain peptide in the lesser Asian scorpion venom. Further extensive mutations of MeuTXKα3 at site 30 could help improve its K(+) channel-blocking and antibacterial functions.
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Affiliation(s)
- Xueli Wang
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects & Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, 100101 Beijing, China
| | - Bin Gao
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects & Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, 100101 Beijing, China
| | - Shunyi Zhu
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects & Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, 100101 Beijing, China.
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6
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Cohen R, Buttke DE, Asano A, Mukai C, Nelson JL, Ren D, Miller RJ, Cohen-Kutner M, Atlas D, Travis AJ. Lipid modulation of calcium flux through CaV2.3 regulates acrosome exocytosis and fertilization. Dev Cell 2014; 28:310-21. [PMID: 24525187 DOI: 10.1016/j.devcel.2014.01.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 10/23/2013] [Accepted: 01/10/2014] [Indexed: 12/14/2022]
Abstract
Membrane lipid regulation of cell function is poorly understood. In early development, sterol efflux and the ganglioside GM1 regulate sperm acrosome exocytosis (AE) and fertilization competence through unknown mechanisms. Here, we show that sterol efflux and focal enrichment of GM1 trigger Ca(2+) influx necessary for AE through CaV2.3, whose activity has been highly controversial in sperm. Sperm lacking CaV2.3's pore-forming α1E subunit showed altered Ca(2+) responses, reduced AE, and a strong subfertility phenotype. Surprisingly, AE depended on spatiotemporal information encoded by flux through CaV2.3, not merely the presence/amplitude of Ca(2+) waves. Using studies in both sperm and voltage clamp of Xenopus oocytes, we define a molecular mechanism for GM1/CaV2.3 regulatory interaction, requiring GM1's lipid and sugar components and CaV2.3's α1E and α2δ subunits. Our results provide a mechanistic understanding of membrane lipid regulation of Ca(2+) flux and therefore Ca(2+)-dependent cellular and developmental processes such as exocytosis and fertilization.
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Affiliation(s)
- Roy Cohen
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Hungerford Hill Road, Ithaca, NY 14853, USA
| | - Danielle E Buttke
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Hungerford Hill Road, Ithaca, NY 14853, USA
| | - Atsushi Asano
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Hungerford Hill Road, Ithaca, NY 14853, USA
| | - Chinatsu Mukai
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Hungerford Hill Road, Ithaca, NY 14853, USA
| | - Jacquelyn L Nelson
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Hungerford Hill Road, Ithaca, NY 14853, USA
| | - Dongjun Ren
- Department of Biochemistry and Molecular Pharmacology, Northwestern University Medical School, 303 E. Chicago Avenue, Chicago, IL 60611, USA
| | - Richard J Miller
- Department of Biochemistry and Molecular Pharmacology, Northwestern University Medical School, 303 E. Chicago Avenue, Chicago, IL 60611, USA
| | - Moshe Cohen-Kutner
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Daphne Atlas
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Alexander J Travis
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Hungerford Hill Road, Ithaca, NY 14853, USA.
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7
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Valdez-Velázquez LL, Quintero-Hernández V, Romero-Gutiérrez MT, Coronas FIV, Possani LD. Mass fingerprinting of the venom and transcriptome of venom gland of scorpion Centruroides tecomanus. PLoS One 2013; 8:e66486. [PMID: 23840487 PMCID: PMC3688770 DOI: 10.1371/journal.pone.0066486] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 05/06/2013] [Indexed: 01/02/2023] Open
Abstract
Centruroides tecomanus is a Mexican scorpion endemic of the State of Colima, that causes human fatalities. This communication describes a proteome analysis obtained from milked venom and a transcriptome analysis from a cDNA library constructed from two pairs of venom glands of this scorpion. High perfomance liquid chromatography separation of soluble venom produced 80 fractions, from which at least 104 individual components were identified by mass spectrometry analysis, showing to contain molecular masses from 259 to 44,392 Da. Most of these components are within the expected molecular masses for Na+- and K+-channel specific toxic peptides, supporting the clinical findings of intoxication, when humans are stung by this scorpion. From the cDNA library 162 clones were randomly chosen, from which 130 sequences of good quality were identified and were clustered in 28 contigs containing, each, two or more expressed sequence tags (EST) and 49 singlets with only one EST. Deduced amino acid sequence analysis from 53% of the total ESTs showed that 81% (24 sequences) are similar to known toxic peptides that affect Na+-channel activity, and 19% (7 unique sequences) are similar to K+-channel especific toxins. Out of the 31 sequences, at least 8 peptides were confirmed by direct Edman degradation, using components isolated directly from the venom. The remaining 19%, 4%, 4%, 15% and 5% of the ESTs correspond respectively to proteins involved in cellular processes, antimicrobial peptides, venom components, proteins without defined function and sequences without similarity in databases. Among the cloned genes are those similar to metalloproteinases.
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Affiliation(s)
| | | | | | - Fredy I. V. Coronas
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Lourival D. Possani
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
- * E-mail:
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Han S, Hu Y, Zhang R, Yi H, Wei J, Wu Y, Cao Z, Li W, He X. ImKTx88, a novel selective Kv1.3 channel blocker derived from the scorpion Isometrus maculates. Toxicon 2010; 57:348-55. [PMID: 21194541 DOI: 10.1016/j.toxicon.2010.12.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Revised: 12/20/2010] [Accepted: 12/20/2010] [Indexed: 01/15/2023]
Abstract
Scorpion toxins are useful in the structure-function research of ion channels and valuable resources for drug design. The Kv1.3 channel is an important pharmacological target for the therapy of T cell-mediated autoimmune diseases, and many toxin peptides targeting Kv1.3 have been identified as good drug candidates in recent years. In this study, a novel toxin gene ImKTx88 was isolated from the venom of the scorpion Isometrus maculates through the construction of the cDNA library method, and the recombinant toxin peptide was purified and characterized physiologically. The mature peptide of ImKTx88 contained 39 amino acid residues including six cysteines and was predicted to be a new member of α-KTx scorpion family by sequence analysis. The electrophysiological experiments further indicated that the rImKTx88 peptide had a novel pharmacological profile: it inhibited Kv1.3 channel current with an IC₅₀ of 91 ± 42 pM, and exhibited very good selectivity for Kv1.3 over Kv1.1 (4200-fold) and Kv1.2 (93000-fold) channels, respectively. All these results suggested that, as a new selective Kv1.3 channel blocker, the ImKTx88 peptide may serve as a potential drug candidate in the therapy of autoimmune diseases.
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Affiliation(s)
- Song Han
- School of Medicine, Wuhan University, Wuhan 430071, People's Republic of China
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Giordanetto F, Knerr L, Wållberg A. T-type calcium channels inhibitors: a patent review. Expert Opin Ther Pat 2010; 21:85-101. [PMID: 21087200 DOI: 10.1517/13543776.2011.536532] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
IMPORTANCE OF THE FIELD T-type calcium channels are transmembrane proteins that regulate calcium entry in the cell in a voltage-dependent manner. Intracellular calcium levels are the key to many physiological processes, ranging from neuron firing to cardiac pacemaking. Inhibition of T-type calcium channels is heralded as a potential treatment to peripheral and CNS disorders, including hypertension, heart failure, sleep, epilepsy, drug addiction and neuropathic pain. AREAS COVERED IN THIS REVIEW A comprehensive summary of patent literature disclosing T-type calcium channels inhibitors is provided. WHAT THE READER WILL GAIN In all, 46 patent applications including 15 chemical structure classes are reviewed. Available in vitro, in vivo and clinical results are also discussed. TAKE HOME MESSAGE Several selective T-type calcium channels inhibitors with demonstrated in vitro and in vivo effects, including one Phase I clinical candidate, are now available. While future clinical results will be paramount to assess target validity in patients, these novel inhibitors represent excellent tools to further investigate the role of T-type channels in pathophysiological conditions.
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Navarrete P, Martínez-Torres A, Gutiérrez RS, Mejía FR, Parodi J. Venom of the ChileanLatrodectus mactansAlters Bovine Spermatozoa Calcium and Function by Blocking the TEA-sensitive K+Current. Syst Biol Reprod Med 2010; 56:303-10. [DOI: 10.3109/19396368.2010.492447] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Parodi J, Navarrete P, Marconi M, Gutiérrez RS, Martínez‐Torres A, Mejías FR. Tetraethylammonium-Sensitive K+Current in the Bovine Spermatozoa and its Blocking by the Venom of the ChileanLatrodectus mactans. Syst Biol Reprod Med 2010; 56:37-43. [DOI: 10.3109/19396360903497217] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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12
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García-Gómez BI, Olamendi-Portugal TC, Paniagua J, van der Walt J, Dyason K, Possani LD. Heterologous expression of a gene that codes for Pg8, a scorpion toxin of Parabuthus granulatus, capable of generating protecting antibodies in mice. Toxicon 2009; 53:770-8. [DOI: 10.1016/j.toxicon.2009.02.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2008] [Revised: 01/22/2009] [Accepted: 02/02/2009] [Indexed: 10/21/2022]
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13
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14
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Zeng XC, Luo F, Li WX. Molecular dissection of venom from Chinese scorpion Mesobuthus martensii: identification and characterization of four novel disulfide-bridged venom peptides. Peptides 2006; 27:1745-54. [PMID: 16513212 DOI: 10.1016/j.peptides.2006.01.012] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2005] [Revised: 01/21/2006] [Accepted: 01/23/2006] [Indexed: 11/28/2022]
Abstract
Scorpion venom is composed of a large repertoire of biologically active polypeptides. However, most of these peptides remain to be identified and characterized. In this paper, we report the identification and characterization of four novel disulfide-bridged venom peptides (named BmKBTx, BmKITx, BmKKx1 and BmKKx2, respectively) from the Chinese scorpion, Mesobuthus martensii (also named Buthus martensii Karsch). BmKBTx is composed of 58 amino acid residues and cross-linked by three disulfide bridges. The sequence of BmKBTx shows some similarities to that of the toxin, birtoxin, and its analogs. It is likely that BmKBTx is a beta-toxin active on Na+ channels, which is toxic to either insects or mammals. BmKITx is composed of 71 amino acid residues with four disulfide bridges. It is the longest venom peptide identified from M. martensii so far. BmKITx shows little sequence identity with scorpion alpha-toxins toxic to insects. It is likely that BmKITx is a new type of Na+ -channel specific toxin active on both insects and mammals. BmKKx1 contains 38 amino acid residues cross-linked by three disulfide bridges and shows 84% sequence identity with BmTx3, an inhibitor of A-type K+ channel and HERG currents. BmKKx1 has been classified as alpha-KTx-15.8. BmKKx2 is composed of 36 residues and stabilized by three disulfide bridges. BmKKx2 is a new member of the gamma-K+ -channel toxin subfamily (classified as gamma-KTx 2.2). The venoms of scorpions thus continue to provide novel toxins with potential novel actions on targets.
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Affiliation(s)
- Xian-Chun Zeng
- State Key Laboratory of Virology, Department of Biotechnology, College of Life Sciences, Wuhan University, Wuhan 430072, PR China
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15
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Zhijian C, Feng L, Yingliang W, Xin M, Wenxin L. Genetic mechanisms of scorpion venom peptide diversification. Toxicon 2006; 47:348-55. [PMID: 16387337 DOI: 10.1016/j.toxicon.2005.11.013] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2005] [Revised: 11/16/2005] [Accepted: 11/21/2005] [Indexed: 11/15/2022]
Abstract
The diversity of scorpion venom peptides is well shown by the presence of about 400 such polypeptides with or without disulfide bonds. Scorpion toxins with disulfide bonds present a variety of sequence features and pharmacological functions by affecting different ion channels, while the venom peptides without disulfide bonds represent a new subfamily, having much lower sequence homology among each other and different functions (e.g. bradykinin-potentiating, antimicrobial, molecular cell signal initiating and immune modulating). Interestingly, all scorpion venom peptides with divergent functions may have evolved from a common ancestor gene. Over the lengthy evolutionary time, the diversification of scorpion venom peptides evolved through polymorphism, duplication, trans-splicing, or alternative splicing at the gene level. In order to completely clarify the diversity of scorpion toxins and toxin-like peptides, toxinomics (genomics and proteomics of scorpion toxins and toxin-like peptides) are expected to greatly advance in the near future.
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Affiliation(s)
- Cao Zhijian
- State Key Laboratory of Virology, College of Life Sciences, Wuhan Uiniversity, Wuhan 430072, People's Republic of China.
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16
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Abstract
Voltage-gated Ca2+ (Ca(v)) channels are found in all excitable cells and many nonexcitable cells, in which they govern Ca2+ influx, thereby contributing to determine a host of important physiological processes including gene transcription, muscle contraction, hormone secretion, and neurotransmitter release. The past years have seen some significant advances in our understanding of the functional, pharmacological, and molecular properties of Ca(v) channels. Molecular studies have revealed that several of these channels are oligomeric complexes consisting of an ion-conducting alpha1 subunit and auxiliary alpha2delta, beta, and gamma subunits. In addition, cloning of multiple Ca(v) channel alpha1 subunits has offered the opportunity to investigate the regulation of these proteins at the molecular level. The regulation of Ca(v) channels by intracellular second messengers constitutes a key mechanism for controlling Ca2+ influx. This review summarizes recent advances that have provided important clues to the underlying molecular mechanisms involved in the regulation of Ca(v) channels by protein phosphorylation, G-protein activation, and interactions with Ca(2+)-binding and SNARE proteins.
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Affiliation(s)
- Ricardo Felix
- Department of Physiology Biophysics, and Neuroscience, Center for Research and Advanced Studies of the National Polytechnic Institute, Cinvestav-IPN, Mexico City, Mexico.
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17
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Mendes TM, Maria WS, Granier C, Chávez-Olórtegui C, Kalapothakis E. Epitope mapping of the antigenic protein TsNTxP from Tityus serrulatus scorpion venom using mouse, rabbit and sheep antibodies. Toxicon 2005; 44:617-24. [PMID: 15501287 DOI: 10.1016/j.toxicon.2004.07.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2004] [Revised: 07/05/2004] [Accepted: 07/06/2004] [Indexed: 11/25/2022]
Abstract
In the present investigation we used native and recombinant TsNTxP to elicit antibodies in three different animal models (mouse, rabbit and sheep). Differences among anti-TsNTxP antibodies were analyzed using sets of overlapping pentadecapeptides of the TsNTxP amino acid sequence and also modified peptides to reveal key residues in antibody-peptide binding. Despite the identification of similar peptides by the antibodies in the C and N-terminal, peculiarities of each system were observed including the level of reactivity and also the number and type of key residues in the continuous epitopes of TsNTxP. In addition, in vitro neutralization assays indicated that sheep are an alternative and efficient model for the production of anti-Tityus serrulatus venom.
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Affiliation(s)
- T M Mendes
- Departamento de Biologia Geral-Genética, ICB, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627 Pampulha, 31270-901 Belo Horizonte, MG, Brazil
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18
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Darszon A, Nishigaki T, Wood C, Treviño CL, Felix R, Beltrán C. Calcium Channels and Ca2+ Fluctuations in Sperm Physiology. INTERNATIONAL REVIEW OF CYTOLOGY 2005; 243:79-172. [PMID: 15797459 DOI: 10.1016/s0074-7696(05)43002-8] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Generating new life in animals by sexual reproduction depends on adequate communication between mature and competent male and female gametes. Ion channels are instrumental in the dialogue between sperm, its environment, and the egg. The ability of sperm to swim to the egg and fertilize it is modulated by ion permeability changes induced by environmental cues and components of the egg outer layer. Ca(2+) is probably the key messenger in this information exchange. It is therefore not surprising that different Ca(2+)-permeable channels are distinctly localized in these tiny specialized cells. New approaches to measure sperm currents, intracellular Ca(2+), membrane potential, and intracellular pH with fluorescent probes, patch-clamp recordings, sequence information, and heterologous expression are revealing how sperm channels participate in fertilization. Certain sperm ion channels are turning out to be unique, making them attractive targets for contraception and for the discovery of novel signaling complexes.
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Affiliation(s)
- Alberto Darszon
- Department of Developmental Genetics and Molecular Physiology, Institute of Biotechnology, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, Mexico 62210
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19
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Bubien JK, Ji HL, Gillespie GY, Fuller CM, Markert JM, Mapstone TB, Benos DJ. Cation selectivity and inhibition of malignant glioma Na+ channels by Psalmotoxin 1. Am J Physiol Cell Physiol 2004; 287:C1282-91. [PMID: 15253892 DOI: 10.1152/ajpcell.00077.2004] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Psalmotoxin 1 (a component of the venom of a West Indies tarantula) is a 40-amino acid peptide that inhibits cation currents mediated by acid-sensing ion channels (ASIC). In this study we performed electrophysiological experiments to test the hypothesis that Psalmotoxin 1 (PcTX1) inhibits Na+ currents in high-grade human astrocytoma cells (glioblastoma multiforme, or GBM). In whole cell patch-clamped cultured GBM cells, the peptide toxin quickly and reversibly inhibited both inward and outward current with an IC50 of 36 +/- 2 pM. The same inhibition was observed in freshly resected GBM cells. However, when the same experiment was performed on normal human astrocytes, the toxin failed to inhibit the whole cell current. We also determined a cationic selectivity sequence for inward currents in three cultured GBM cell lines (SK-MG-1, U87-MG, and U251-MG). The selectivity sequence yielded a unique biophysical fingerprint with inward K+ conductance approximately fourfold greater than that of Na+, Li+, and Ca2+. These observations suggest that PcTX1 may prove useful in determining whether GBM cells express a specific ASIC-containing ion channel type that can serve as a target for both diagnostic and therapeutic treatments of aggressive malignant gliomas.
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Affiliation(s)
- James K Bubien
- Department of Physiology and Biophysics, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA.
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20
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Felix R, Sandoval A, Sánchez D, Gómora JC, De la Vega-Beltrán JL, Treviño CL, Darszon A. ZD7288 inhibits low-threshold Ca2+ channel activity and regulates sperm function. Biochem Biophys Res Commun 2003; 311:187-92. [PMID: 14575712 DOI: 10.1016/j.bbrc.2003.09.197] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In this study, ZD7288, a blocker of hyperpolarization-activated and cyclic nucleotide-gated (HCN) channels, has been found to inhibit the mouse sperm acrosome reaction (AR). HCN channels have not yet been either recorded or implicated in mouse sperm AR, but low-threshold (T-type) Ca(2+) channels have. Interestingly, ZD7288 blocked native T-type Ca(2+) currents in mouse spermatogenic cells with an IC(50) of about 100 microM. This blockade was more effective at voltages producing low levels of inactivation, suggesting a differential affinity of ZD7288 for different channel conformations. Furthermore, ZD7288 inhibited all cloned T-type but not high-threshold N-type channels heterologously expressed in HEK-293 cells. Our results further support the role of T-type Ca(2+) channels in the mouse sperm AR.
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Affiliation(s)
- Ricardo Felix
- Department of Physiology, Biophysics and Neuroscience, Cinvestav-IPN, Mexico City, Mexico
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21
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Yudin AI, Tollner TL, Li MW, Treece CA, Overstreet JW, Cherr GN. ESP13.2, a member of the beta-defensin family, is a macaque sperm surface-coating protein involved in the capacitation process. Biol Reprod 2003; 69:1118-28. [PMID: 12773404 DOI: 10.1095/biolreprod.103.016105] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Female macaques produced isoantibodies to a limited number of sperm surface proteins following immunization with sperm components released by phosphatidylinositol-specific phospholipase C (PI-PLC). Washed, acrosome-intact, fixed sperm injected into rabbits elicited a major immune response to one of the same PI-PLC-released proteins, which was shown to be a sperm surface-coating protein. After purification and digestion of the glycoprotein, four peptides were analyzed for amino acid sequence, and all had 100% homology with an epididymal secretory protein, ESP13.2, reported previously to be a small, cationic-rich peptide and a member of the beta-defensin family. Antibodies to purified ESP13.2 recognized a number of protein bands on Western blots of nonreduced PI-PLC-released sperm components and nonreduced whole-sperm extracts. After chemical disulfide reduction, only a single, broad band from 31 to 35 kDa was recognized by anti-ESP13.2 antibodies. Indirect immunofluorescence showed ESP13.2 over the entire surface of ejaculated macaque sperm. Fluorescence was only slightly reduced after sperm were washed through 80% Percoll. A 24-h incubation in capacitating medium significantly reduced the amount of ESP13.2 over the head and midpiece, whereas exposure of the incubated sperm to dbcAMP and caffeine (capacitation activators) resulted in almost complete loss of ESP13.2 from the sperm surface. After activation, ESP13.2 was the primary component released into the medium as judged electrophoretically. Lignosulfonic acid, a potent inhibitor of macaque fertilization in vitro, completely blocked release of ESP13.2 from the sperm surface, even following treatment with activators. These findings suggest that the beta-defensin, ESP13.2, has a function in the capacitation of macaque spermatozoa and may modulate sperm surface-receptor presentation at the time of fertilization.
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Affiliation(s)
- Ashley I Yudin
- Department of Obstetrics and Gynecology, Division of Reproductive Biology, University of California, Davis 94923, USA
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22
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Olamendi-Portugal T, García BI, López-González I, Van Der Walt J, Dyason K, Ulens C, Tytgat J, Felix R, Darszon A, Possani LD. Two new scorpion toxins that target voltage-gated Ca2+ and Na+ channels. Biochem Biophys Res Commun 2002; 299:562-8. [PMID: 12459175 DOI: 10.1016/s0006-291x(02)02706-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
This report describes the isolation, primary structure determination, and functional characterization of two similar toxins from the scorpion Parabuthus granulatus named kurtoxin-like I and II (KLI and KLII, respectively). KLII from P. granulatus is identical to kurtoxin from Parabuthus transvaalicus (a 63 amino-acid long toxin) whereas KLI is a new peptide containing 62 amino acid residues closely packed by four disulfide bridges with a molecular mass of 7244. Functional assays showed that both toxins, KLI and kurtoxin from P. granulatus, potently inhibit native voltage-gated T-type Ca(2+) channel activity in mouse male germ cells. In addition, KLI was shown to significantly affect the gating mechanisms of recombinant Na(+) channels and weakly block alpha(1)3.3Ca(V) channels expressed in Xenopus oocytes. KLI and kurtoxin from P. granulatus represent new probes to study the role of ion channels in germ cells, as well as in cardiac and neural tissue.
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Affiliation(s)
- Timoteo Olamendi-Portugal
- Department of Molecular Medicine and Bioprocesses, Institute of Biotechnology, National Autonomous University of Mexico, Apartado Postal 510-3 Cuernavaca 62210, Mexico
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