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Montassar F, Darche M, Blaizot A, Augustin S, Conart JB, Millet A, Elayeb M, Sahel JA, Réaux-Le Goazigo A, Sennlaub F, Marrakchi N, Messadi E, Guillonneau X. Lebecetin, a C-type lectin, inhibits choroidal and retinal neovascularization. FASEB J 2016; 31:1107-1119. [PMID: 27974593 DOI: 10.1096/fj.201600351r] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 11/28/2016] [Indexed: 12/14/2022]
Abstract
Angiogenesis is a cause of visual impairment and blindness in the wet form of age-related macular degeneration and in ischemic retinopathies. Current therapies include use of anti-VEGF agents to reduce choroidal neovascularization (CNV) and edema. These treatments are effective in most cases, but spontaneous or acquired resistance to anti-VEGF and possible adverse effects of long-term VEGF inhibition in the retina and choroid highlight a need for additional alternative therapies. Integrins αvβ3 and αvβ5, which regulate endothelial cell proliferation and stabilization, have been implicated in ocular angiogenesis. Lebecetin (LCT) is a 30-kDa heterodimeric C-type lectin that is isolated from Macrovipera lebetina venom and interacts with α5β1- and αv-containing integrins. We previously showed that LCT inhibits human brain microvascular endothelial cell adhesion, migration, proliferation, and tubulogenesis. To evaluate the inhibitory effect of LCT on ocular angiogenesis, we cultured aortic and choroidal explants in the presence of LCT and analyzed the effect of LCT on CNV in the mouse CNV model and on retinal neovascularization in the oxygen-induced retinopathy model. Our data demonstrate that a single injection of LCT efficiently reduced CNV and retinal neovascularization in these models.-Montassar, F., Darche, M., Blaizot, A., Augustin, S., Conart, J.-B., Millet, A., Elayeb, M., Sahel, J.-A., Réaux-Le Goazigo, A., Sennlaub, F., Marrakchi, N., Messadi, E., Guillonneau, X. Lebecetin, a C-type lectin, inhibits choroidal and retinal neovascularization.
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Affiliation(s)
- Fadoua Montassar
- Sorbonne Universités, Université Pierre et Marie Curie, INSERM, Centre National de la Recherche Scientifique, Institut de la Vision, Paris, France.,Laboratoire des Venins et Biomolécules Thérapeutiques LR11IPT08, Institut Pasteur de Tunis, Tunis, Tunisia.,Université de Carthage, Faculté des Sciences de Bizerte, Bizerte, Tunisia
| | - Marie Darche
- Sorbonne Universités, Université Pierre et Marie Curie, INSERM, Centre National de la Recherche Scientifique, Institut de la Vision, Paris, France
| | - Amandine Blaizot
- Sorbonne Universités, Université Pierre et Marie Curie, INSERM, Centre National de la Recherche Scientifique, Institut de la Vision, Paris, France
| | - Sébastien Augustin
- Sorbonne Universités, Université Pierre et Marie Curie, INSERM, Centre National de la Recherche Scientifique, Institut de la Vision, Paris, France
| | - Jean-Baptiste Conart
- Sorbonne Universités, Université Pierre et Marie Curie, INSERM, Centre National de la Recherche Scientifique, Institut de la Vision, Paris, France
| | - Aurélie Millet
- Laboratoire des Venins et Biomolécules Thérapeutiques LR11IPT08, Institut Pasteur de Tunis, Tunis, Tunisia
| | - Mohamed Elayeb
- Laboratoire des Venins et Biomolécules Thérapeutiques LR11IPT08, Institut Pasteur de Tunis, Tunis, Tunisia
| | - José-Alain Sahel
- Sorbonne Universités, Université Pierre et Marie Curie, INSERM, Centre National de la Recherche Scientifique, Institut de la Vision, Paris, France
| | - Annabelle Réaux-Le Goazigo
- Sorbonne Universités, Université Pierre et Marie Curie, INSERM, Centre National de la Recherche Scientifique, Institut de la Vision, Paris, France
| | - Florian Sennlaub
- Sorbonne Universités, Université Pierre et Marie Curie, INSERM, Centre National de la Recherche Scientifique, Institut de la Vision, Paris, France
| | - Naziha Marrakchi
- Laboratoire des Venins et Biomolécules Thérapeutiques LR11IPT08, Institut Pasteur de Tunis, Tunis, Tunisia
| | - Erij Messadi
- Laboratoire des Venins et Biomolécules Thérapeutiques LR11IPT08, Institut Pasteur de Tunis, Tunis, Tunisia
| | - Xavier Guillonneau
- Sorbonne Universités, Université Pierre et Marie Curie, INSERM, Centre National de la Recherche Scientifique, Institut de la Vision, Paris, France;
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Tourki B, Matéo P, Morand J, Elayeb M, Godin-Ribuot D, Marrakchi N, Belaidi E, Messadi E. Lebetin 2, a Snake Venom-Derived Natriuretic Peptide, Attenuates Acute Myocardial Ischemic Injury through the Modulation of Mitochondrial Permeability Transition Pore at the Time of Reperfusion. PLoS One 2016; 11:e0162632. [PMID: 27618302 PMCID: PMC5019389 DOI: 10.1371/journal.pone.0162632] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 08/25/2016] [Indexed: 12/28/2022] Open
Abstract
Cardiac ischemia is one of the leading causes of death worldwide. It is now well established that natriuretic peptides can attenuate the development of irreversible ischemic injury during myocardial infarction. Lebetin 2 (L2) is a new discovered peptide isolated from Macrovipera lebetina venom with structural similarity to B-type natriuretic peptide (BNP). Our objectives were to define the acute cardioprotective actions of L2 in isolated Langendorff-perfused rat hearts after regional or global ischemia-reperfusion (IR). We studied infarct size, left ventricular contractile recovery, survival protein kinases and mitochondrial permeability transition pore (mPTP) opening in injured myocardium. L2 dosage was determined by preliminary experiments at its ability to induce cyclic guanosine monophosphate (cGMP) release without changing hemodynamic effects in normoxic hearts. L2 was found to be as effective as BNP in reducing infarct size after the induction of either regional or global IR. Both peptides equally improved contractile recovery after regional IR, but only L2 increased coronary flow and reduced severe contractile dysfunction after global ischemia. Cardioprotection afforded by L2 was abolished after isatin or 5-hydroxydecanote pretreatment suggesting the involvement of natriuretic peptide receptors and mitochondrial KATP (mitoKATP) channels in the L2-induced effects. L2 also increased survival protein expression in the reperfused myocardium as evidenced by phosphorylation of signaling pathways PKCε/ERK/GSK3β and PI3K/Akt/eNOS. IR induced mitochondrial pore opening, but this effect was markedly prevented by L2 treatment. These data show that L2 has strong cardioprotective effect in acute ischemia through stimulation of natriuretic peptide receptors. These beneficial effects are mediated, at least in part, by mitoKATP channel opening and downstream activated survival kinases, thus delaying mPTP opening and improving IR-induced mitochondrial dysfunction.
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Affiliation(s)
- Bochra Tourki
- Laboratoire des Venins et Biomolécules Thérapeutiques (LR11IPT08) et Plateforme de Physiologie et de Physiopathologie Cardiovasculaires (P2C), Institut Pasteur de Tunis, Université Tunis El Manar, Tunis, Tunisia
- Université Carthage Tunis, Bizerte, Tunisia
| | - Philippe Matéo
- Laboratoire de Signalisation et Physiopathologie Cardiovasculaire, UMR-S 1180, Faculté de Pharmacie, Université Paris Sud, Paris, France
| | - Jessica Morand
- Laboratoire d’Hypoxie et Physiopathologie Cardiaque, Inserm U1042, Faculté de Pharmacie, Université Grenoble Alpes, Grenoble, France
| | - Mohamed Elayeb
- Laboratoire des Venins et Biomolécules Thérapeutiques (LR11IPT08) et Plateforme de Physiologie et de Physiopathologie Cardiovasculaires (P2C), Institut Pasteur de Tunis, Université Tunis El Manar, Tunis, Tunisia
| | - Diane Godin-Ribuot
- Laboratoire d’Hypoxie et Physiopathologie Cardiaque, Inserm U1042, Faculté de Pharmacie, Université Grenoble Alpes, Grenoble, France
| | - Naziha Marrakchi
- Laboratoire des Venins et Biomolécules Thérapeutiques (LR11IPT08) et Plateforme de Physiologie et de Physiopathologie Cardiovasculaires (P2C), Institut Pasteur de Tunis, Université Tunis El Manar, Tunis, Tunisia
| | - Elise Belaidi
- Laboratoire d’Hypoxie et Physiopathologie Cardiaque, Inserm U1042, Faculté de Pharmacie, Université Grenoble Alpes, Grenoble, France
| | - Erij Messadi
- Laboratoire des Venins et Biomolécules Thérapeutiques (LR11IPT08) et Plateforme de Physiologie et de Physiopathologie Cardiovasculaires (P2C), Institut Pasteur de Tunis, Université Tunis El Manar, Tunis, Tunisia
- * E-mail:
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3
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Ayari-Riabi S, Trimaille T, Mabrouk K, Bertin D, Gigmes D, Benlasfar Z, Zaghmi A, Bouhaouala-Zahar B, Elayeb M. Venom conjugated polylactide applied as biocompatible material for passive and active immunotherapy against scorpion envenomation. Vaccine 2016; 34:1810-5. [PMID: 26902547 DOI: 10.1016/j.vaccine.2016.02.030] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Revised: 01/15/2016] [Accepted: 02/10/2016] [Indexed: 12/20/2022]
Abstract
Scorpion envenoming represents a public health issue in subtropical regions of the world. Treatment and prevention need to promote antitoxin immunity. Preserving antigenic presentation while removing toxin effect remains a major challenge in toxin vaccine development. Among particulate adjuvant, particles prepared with poly (D,L-lactide) polymer are the most extensively investigated due to their excellent biocompatibility and biodegradability. The aim of this study is to develop surfactant-free PLA nanoparticles that safely deliver venom toxic fraction to enhance specific immune response. PLA nanoparticles are coated with AahG50 (AahG50/PLA) and BotG50 (BotG50/PLA): a toxic fraction purified from Androctonus australis hector and Buthus occitanus tunetanus venoms, respectively. Residual toxicities are evaluated following injections of PLA-containing high doses of AahG50 (or BotG50). Immunization trials are performed with the detoxified fraction administered alone without adjuvant. A comparative study of the effect of Freund is also included. The neutralizing capacity of sera is determined in naive mice. Six months later, immunized mice are challenged subcutaneously with increased doses of AahG50. Subcutaneous lethal dose 50 (LD50) of AahG50 and BotG50 is of 575 μg/kg and 1300 μg/kg respectively. By comparison, BotG50/PLA is totally innocuous while 50% of tested mice survive 2875 μg AahG50/kg. Alhydrogel and Freund are not able to detoxify such a high dose. Cross-antigenicity between particulate and soluble fraction is also, ensured. AahG50/PLA and BotG50/PLA induce high antibody levels in mice serum. The neutralizing capacity per mL of anti-venom was 258 μg/mL and 186 μg/mL calculated for anti-AahG50/PLA and anti-BotG50/PLA sera, respectively. Animals immunized with AahG50/PLA are protected against AahG50 injected dose of 3162 μg/kg as opposed all non-immunized mice died at this dose. We find that the detoxification approach based PLA nanoparticles, benefit the immunogenicity and protective efficacy of venom immunogen.
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Affiliation(s)
- Sana Ayari-Riabi
- Laboratoire des Venins et Molécules Thérapeutiques, Institut Pasteur Tunis - University Tunis El Manar, BP 74, 13 Place Pasteur, 1002 Tunis, Tunisia; Faculté des Sciences de Bizerte, 7021 Jarzouna, Tunisia.
| | - Thomas Trimaille
- Institut de chimie radicalaire, Equipe Chimie Radicalaire, Organique et Polymères de Spécialité (CROPS), (CNRS - UMR7273), Aix-Marseille University, avenue Escadrille Normandie-Niemen, 13397 Marseille cedex 20, France
| | - Kamel Mabrouk
- Institut de chimie radicalaire, Equipe Chimie Radicalaire, Organique et Polymères de Spécialité (CROPS), (CNRS - UMR7273), Aix-Marseille University, avenue Escadrille Normandie-Niemen, 13397 Marseille cedex 20, France
| | - Denis Bertin
- Institut de chimie radicalaire, Equipe Chimie Radicalaire, Organique et Polymères de Spécialité (CROPS), (CNRS - UMR7273), Aix-Marseille University, avenue Escadrille Normandie-Niemen, 13397 Marseille cedex 20, France
| | - Didier Gigmes
- Institut de chimie radicalaire, Equipe Chimie Radicalaire, Organique et Polymères de Spécialité (CROPS), (CNRS - UMR7273), Aix-Marseille University, avenue Escadrille Normandie-Niemen, 13397 Marseille cedex 20, France
| | - Zakaria Benlasfar
- Service des Unités Animalières, Institut Pasteur Tunis - BP 74, 13 Place Pasteur, 1002 Tunis, Tunisia
| | - Ahlem Zaghmi
- Laboratoire des Venins et Molécules Thérapeutiques, Institut Pasteur Tunis - University Tunis El Manar, BP 74, 13 Place Pasteur, 1002 Tunis, Tunisia
| | - Balkiss Bouhaouala-Zahar
- Laboratoire des Venins et Molécules Thérapeutiques, Institut Pasteur Tunis - University Tunis El Manar, BP 74, 13 Place Pasteur, 1002 Tunis, Tunisia
| | - Mohamed Elayeb
- Laboratoire des Venins et Molécules Thérapeutiques, Institut Pasteur Tunis - University Tunis El Manar, BP 74, 13 Place Pasteur, 1002 Tunis, Tunisia.
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Jguirim M, Mani L, Mhenni A, Klii R, Moula G, Elayeb M, Younes M, Zrour S, Bejia I, Touzi M, Bergaoui N. Ostéogenèse imparfaite en rhumatologie : à propos de 12 cas. Rev Med Interne 2014. [DOI: 10.1016/j.revmed.2014.10.312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Jguirim M, Mhenni A, Klii R, Mani L, Elayeb M, Moula G, Younes M, Zrour S, Bejia I, Touzi M, Bergaoui N. Comorbidités cardiovasculaires au cours des spondyloarthropathie. Rev Med Interne 2014. [DOI: 10.1016/j.revmed.2014.10.313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Jguirim M, Mani L, Mhenni A, Klii R, Elayeb M, Moula G, Younes M, Zrour S, Bejia I, Touzi M, Bergaoui N. Profil évolutif et thérapeutique dans la polyarthrite rhumatoïde : à propos de 100 cas. Rev Med Interne 2014. [DOI: 10.1016/j.revmed.2014.10.314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Rjeibi I, Mabrouk K, Mosrati H, Berenguer C, Mejdoub H, Villard C, Laffitte D, Bertin D, Ouafik L, Luis J, Elayeb M, Srairi-Abid N. Purification, synthesis and characterization of AaCtx, the first chlorotoxin-like peptide from Androctonus australis scorpion venom. Peptides 2011; 32:656-63. [PMID: 21262299 DOI: 10.1016/j.peptides.2011.01.015] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Revised: 01/11/2011] [Accepted: 01/11/2011] [Indexed: 01/18/2023]
Abstract
AaCtx is the first chlorotoxin-like peptide isolated from Androctonus australis scorpion venom. Its amino acid sequence shares 70% similarity with chlorotoxin from Leiurus quinquestriatus scorpion venom, from which it differs by twelve amino acids. Due to its very low concentration in venom (0.05%), AaCtx was chemically synthesized. Both native and synthetic AaCtx were active on invasion and migration of human glioma cells. However, their activity was found to be lower than that of chlorotoxin. The molecular model of AaCtx shows that most of amino acids differing between AaCtx and chlorotoxin are localized on the N-terminal loop and the α-helix. Based on known compounds that block chloride channels, we suggest that the absence of negative charged amino acids on AaCtx structure may be responsible for its weak activity on glioma cells migration and invasion. This finding serves as a starting point for structure-function relationship studies leading to design high specific anti-glioma drugs.
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Affiliation(s)
- Ilhem Rjeibi
- Laboratoire des Venins et Toxines, Institut Pasteur de Tunis, 13, Place Pasteur, BP 74, 1002 Belvédère, Universités Tunis-El Manar, Tunisia
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Nouira S, Elatrous S, Besbes L, Boukef R, Devaux C, Aubrey N, Elayeb M, Abroug F. Neurohormonal activation in severe scorpion envenomation: correlation with hemodynamics and circulating toxin. Toxicol Appl Pharmacol 2005; 208:111-6. [PMID: 16183384 DOI: 10.1016/j.taap.2005.01.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2004] [Revised: 12/23/2004] [Accepted: 01/31/2005] [Indexed: 11/30/2022]
Abstract
We studied the effects of scorpion (Androctonus australis hector) venom on hemodynamics and on the release of catecholamines, neuropeptide Y (NPY), endothelin-1 (ET-1) and atrial natriuretic peptide (ANP) in dog model of severe scorpion envenomation. Nine mongrel anesthetized dogs were submitted to mechanical ventilation through intubation and were administered intravenously purified dried scorpion venom (Androctonus autstralis) 0.05 mg/kg. Measurements including pulmonary artery catheter derived parameters, serum toxin levels and humoral variables were performed at baseline (before venom injection) and 5, 15, 30 and 60 min after venom injection. Humoral variables included: serum lactate, epinephrine (EP), norepinephrine (NE), NPY, ET-1 and ANP plasma concentrations. Scorpion venom caused rapid and transient increase of mean arterial pressure (MAP) and PAOP associated with a marked and sustained decline in cardiac output (-55% at 60 min; P < 0.001). Hemodynamic changes were associated with a rapid and significant increase of all measured hormones. The highest increase was for NE (28-fold) and EP (25-fold). MAP was closely correlated with NE and less significantly correlated with toxin levels. Similarly, significant correlation was observed between PAPO and ANP plasma levels. These findings support the implication of excessive catecholamines release in hemodynamic disturbances of severe SE and suggest that NPY and ET-1 could be involved in this process. Serum toxin does not appear to consistently contribute to these effects. Through its correlation with PAOP, ANP could be a reliable and useful marker of cardiac dysfunction in SE.
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Affiliation(s)
- Semir Nouira
- Service de Réanimation Médicale and Experimental Toxicology Unit (99/UR/088-59 and UR/06/02), Fattouma Bourguiba University Hospital Monastir 5000, Tunisia.
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Gasmi A, Abidi F, Srairi N, Oijatayer A, Karoui H, Elayeb M. Purification and characterization of a growth factor-like which increases capillary permeability from Vipera lebetina venom. Biochem Biophys Res Commun 2000; 268:69-72. [PMID: 10652214 DOI: 10.1006/bbrc.2000.2078] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have investigated the effect of Vipera lebetina venom on capillary permeability and isolated an increasing capillary permeability protein (ICPP) which is devoid of arginine ester hydrolase and phospholipase A2 activities. This protein was purified with a yield of about 0.2% by fast protein liquid chromatography (FPLC) using successively Superose 12, Mono Q, and Mono S columns and by high-pressure liquid chromatography (HPLC) on a C8 reverse-phase column. The purified protein migrated on SDS-PAGE as a band of about 27 kDa under nonreducing conditions and as a band of about 16 kDa under reducing conditions. Chromatography on a C8 column of reduced and alkylated protein yielded a single peak suggesting that this protein is homodimeric. This protein was refractory to Edman degradation chemistry. We used successfully a chemical unblocking involving the incubation of the protein with HCl in anhydrous methanol. The N-terminal amino acid sequence clearly shows considerable similarity to that of vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF).
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Affiliation(s)
- A Gasmi
- Laboratoire Venins et Toxines, Institut Pasteur de Tunis, Tunis-Belvédère, Tunisia.
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Gasmi A, Chabchoub A, Guermazi S, Karoui H, Elayeb M, Dellagi K. Further characterization and thrombolytic activity in a rat model of a fibrinogenase from Vipera lebetina venom. Thromb Res 1997; 86:233-42. [PMID: 9175244 DOI: 10.1016/s0049-3848(97)00066-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Vipera lebetina fibrinogenase (VlF) was shown to render fibrinogen incoagulable and to solubilize fibrin. The fibrinogenolytic activity of this enzyme was found to be 33 mg fibrinogen/min/mg protein. The study of the specificity of this enzyme revealed that it has no effect on purified factor X, prothrombin and protein C and on the specific chromogenic substrates of their active form. Plasminogen was not activated by VlF but slightly degraded. We have also compared the effect of VlF and plasmin on fibrinogen and shown that these two enzymes have a different sites of cleavage. This enzyme inhibited human platelet aggregation on PRP initiated by ADP and collagen but was without effect on the aggregation of washed rabbit platelets using thrombin as agonist. Administration of VlF in rat did not show any necrosis or hemorrhage in treated rats organ's. We therefore, examined the thrombolytic activity of VlF in a rat model of venous thrombosis. Thrombus was produced in the posterior vena cava by injection of human fibrinogen and thrombin. Injection of 5 mg/Kg body weight showed an evident flow restoration after one hour and measurement of the fibrinogen level a decrease of about 30% after 3 hrs. VlF's action is not dependent on plasminogen activators and may act synergistically with them, thereby providing an intriguing potential clinical application for dissolution of blood clots.
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Affiliation(s)
- A Gasmi
- Laboratoire venins et toxines, Institut Pasteur de Tunis, Tunisia
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11
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Aouani ME, Mhamdi R, Mars M, Elayeb M, Ghtir R. Potential for inoculation of common bean by effective rhizobia in Tunisian soils. ACTA ACUST UNITED AC 1997. [DOI: 10.1051/agro:19970902] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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12
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Bahraoui E, Pichon J, Muller JM, Darbon H, Elayeb M, Granier C, Marvaldi J, Rochat H. Monoclonal antibodies to scorpion toxins: characterization and molecular mechanisms of neutralization. The Journal of Immunology 1988. [DOI: 10.4049/jimmunol.141.9.3241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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13
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Bahraoui E, Pichon J, Muller JM, Darbon H, Elayeb M, Granier C, Marvaldi J, Rochat H. Monoclonal antibodies to scorpion toxins. Characterization and molecular mechanisms of neutralization. The Journal of Immunology 1988. [DOI: 10.4049/jimmunol.141.1.214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
Two mAb specific for the potent toxin II of the scorpion Androctonus australis Hector have been produced. One of them shows both high affinity binding to the toxin (Kd) = 0.8 nM) and in vivo and in vitro neutralizing properties. The mechanism by which the antibody neutralizes toxin binding to its receptor was shown to be of the competitive type, the epitope overlapping or being close to the receptor-binding region of the toxin. Several residues of the toxin clustered in the C-terminal region were shown likely to be part of the discontinuous epitope recognized by the antibody. The positive charge of the N epsilon-Lys-58 seems to play a pivotal role in the binding of the toxin to both the mAb and the sodium channel receptor.
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Affiliation(s)
- E Bahraoui
- Laboratoire de Biochimie, CNRS UA 1179, Marseille, France
| | - J Pichon
- Laboratoire de Biochimie, CNRS UA 1179, Marseille, France
| | - J M Muller
- Laboratoire de Biochimie, CNRS UA 1179, Marseille, France
| | - H Darbon
- Laboratoire de Biochimie, CNRS UA 1179, Marseille, France
| | - M Elayeb
- Laboratoire de Biochimie, CNRS UA 1179, Marseille, France
| | - C Granier
- Laboratoire de Biochimie, CNRS UA 1179, Marseille, France
| | - J Marvaldi
- Laboratoire de Biochimie, CNRS UA 1179, Marseille, France
| | - H Rochat
- Laboratoire de Biochimie, CNRS UA 1179, Marseille, France
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14
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Bahraoui E, Pichon J, Muller JM, Darbon H, Elayeb M, Granier C, Marvaldi J, Rochat H. Monoclonal antibodies to scorpion toxins. Characterization and molecular mechanisms of neutralization. J Immunol 1988; 141:214-20. [PMID: 2454259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Two mAb specific for the potent toxin II of the scorpion Androctonus australis Hector have been produced. One of them shows both high affinity binding to the toxin (Kd) = 0.8 nM) and in vivo and in vitro neutralizing properties. The mechanism by which the antibody neutralizes toxin binding to its receptor was shown to be of the competitive type, the epitope overlapping or being close to the receptor-binding region of the toxin. Several residues of the toxin clustered in the C-terminal region were shown likely to be part of the discontinuous epitope recognized by the antibody. The positive charge of the N epsilon-Lys-58 seems to play a pivotal role in the binding of the toxin to both the mAb and the sodium channel receptor.
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Affiliation(s)
- E Bahraoui
- Laboratoire de Biochimie, CNRS UA 1179, Marseille, France
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