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Fatima Larabadjebari - One of the best experts on this subject based on the ideXlab platform.

  • computational and functional characterization of a hemorrhagic metalloproteinase purified from Cerastes Cerastes venom
    Protein Journal, 2021
    Co-Authors: Amel Bennacer, Hinda Boukhalfaabib, Fatima Larabadjebari
    Abstract:

    Structural and functional aspects of snake venoms metalloproteinases (SVMPs) have been extensively studied due to their role in envenomation. However, in the detection of certain coagulation disorders these biomolecules have been used and applied for the production of new thrombolytic drugs. CcMP-II, a SVMP-II metalloproteinase with a hemorrhagic activity, isolated from the venom of Cerastes Cerastes, its sequence of 472 amino acids was identified. Predicted 3D structure showed an arrangement of CcMP-II into two distinct domains: i) a metalloproteinase domain where the zinc-binding motif is found (HXXGHNLGIDH) in addition to the sequence Cys‐Ile‐Met (CIM) at the Met-turn and ii) disintegrin-like domain containing RGD motif. CcMP-II inhibits platelet aggregation induced by collagen in a dose-dependent manner with an IC50 value estimated of 0.11 nM. This proteinase inhibits also aggregation of platelet stimulated by collagen even if the metal chelating agents (EDTA and 1, 10-phenontroline) are present suggesting that anti-aggregating effect is not due to its metalloproteinase domain, but to its disintegrin-like domain. Capillary pathological modifications caused by CcMP-II following intramuscular injection have as well been examined in mice. The key morphological alterations of the capillary vessels were clearly apparent from the ultrastructural study. The CcMP-II can play a key function in the pathogenesis of disorders that occurs following envenomation of Cerastes Cerastes. The three-dimensional model of CcMP-II was built to explain structure–function relationships in ADAM/ADAMTs, a family of proteins having significant therapeutic potential. In order to explain structure–function relationships in ADAM / ADAMT, a family of proteins with considerable therapeutic potential, the three-dimensional model of CcMP-II was constructed.

  • isolation and characterization of cd39 like phosphodiesterase cc pde from Cerastes Cerastes venom molecular inhibitory mechanism of antiaggregation and anticoagulation
    Protein and Peptide Letters, 2021
    Co-Authors: Hamida Kiheli, Fatah Cherifi, Meriem Ameziani, Samah Saoud, Ghania Hariti, Fatima Larabadjebari
    Abstract:

    Background Cerastes Cerastes venom contains several bioactive proteins with inhibitory potential of platelet aggregation and blood coagulation. Objective The current study deals with purification, characterization and determination of structural properties of Cc-PDE, the first phosphodiesterase from Cerastes Cerastes venom. Material and methods The purification process consists of three successive chromatographies including G75-Sephadex size exclusion, DEAE exchange chromatography and affinity using Sildenafil as a main PDEs' specific inhibitor. The amino acid sequence of purified Cc-PDE was determined by liquid chromatography coupled off line to MALDI-TOF/TOF. Modeling and structural features were obtained using several bioinformatics tools. In vivo and in vitro antiplatelet aggregation and anticoagulant assays were performed. Results Cc-PDE (73 506.42 Da) is a 654-residue single polypeptide with 1-22 signal peptide and it is characterized by the presence of predominant basic amino acids suitable to alkaline pI (8.17). Cc-PDE structure is composed of β-strands (17%) and α-helices (24%) and it shares a high identity with homologous snake venom PDEs. Cc-PDE hydrolyzes both Bis-p-nitrophenyl phosphate (Km = 2.60 ± 0.95 mM, Vmax = 0.017 ± 0.002569 μmol.min-1) and p-nitrophenyl phosphate (Km = 7.13 mM ± 0.04490 mM, Vmax = 0.053 ±0.012 μmol.min-1). Cc-PDE prevents ADP- and ATP-induced platelet aggregation by hydrolyzing ADP and ATP, reducing surface P-selectin expression and attenuating platelet function. In addition, Cc-PDE inhibits coagulation factors involved in the intrinsic pathway demonstrated by a significant prolongation of activated partial thromboplastin time and in vivo long-lasting anticoagulation. Conclusion The obtained results revealed that Cc-PDE may have a therapeutic potential and could be a remedy for thromboembolic diseases as an alternative of anticoagulant and antiplatelet aggregation chemical origins.

  • myotoxicity induced by Cerastes Cerastes venom beneficial effect of heparin in skeletal muscle tissue regeneration
    Acta Tropica, 2020
    Co-Authors: Fatima Zohra Nourreddine, Habiba Oussedikoumehdi, Fatima Larabadjebari
    Abstract:

    Abstract Myonecrosis is a relevant tissue damage induced by snakes of Viperidae family often leading to permanent tissue and function loss and even amputation. The aim of this study was to evaluate the effect of heparin on skeletal muscle tissue regeneration after Cerastes Cerastes envenomation. Mice received either the venom (1 LD50) by i.m. route, or the venom followed, by heparin administration by i.v. route at 15 min and 4 h. Obtained results showed that Cerastes Cerastes venom induced deep tissue structure alterations, characterized mainly by edema, hemorrhage, myonecrosis and inflammation. Myotoxicity was correlated with increased CK levels in sera, concomitant with their decrease in muscle tissue homogenates. Muscle wet weight was restored within 2 weeks after heparin treatment and 28 days in the envenomed group. Heparin treatment significantly decreased MPO activity, suggesting an anti-inflammatory effect. NO, HGF, VEGF and G-CSF levels were increased after heparin administration. These mitogenic factors constitute potent stimuli for satellite and endothelial cells improving, thus, muscle regeneration. This study showed that muscle tissue recovery was significantly enhanced after heparin treatment. Heparin use seems to be a promising therapeutic approach after viper envenomation.

  • isolation and in silico characterization of a leishmanicidal disintegrin from Cerastes Cerastes venom
    Acta HealthMedica, 2019
    Co-Authors: Dihia Allane, Habiba Oussedikoumehdi, Zoubir Harrat, Michel Seve, Sylvie Michelland, Fatima Larabadjebari
    Abstract:

    Background: Leishmaniasis represents a serious public health problem in Algeria. The parasite, in the promastigote form, upon transfer by the infected vector to the vertebrate host, invades mononuclear macrophages and causes substantial human morbidity and mortality. Investigating new antimicrobial and antiparasitic components from Viperidae venoms represents an alternative therapeutic strategy for leishmaniasis treatment. Objective: In the present study, we report the characterization of a disintegrin, isolated from Cerastes Cerastes venom, exhibiting antiparasitic activity on Leishmania infantum promastigotes. Methods: The active biomolecule, referred to as Disintegrin_Cc, was isolated by RP-HPLC chromatography. The in vitro antiparasitic activity of this molecule was evaluated on Leishmania infantum promastigotes. The isolated disintegrin was analyzed by SDS-PAGE for homogeneity and molecular weight determination and then subjected to MALDI-TOF MS/MS analysis. A 3D structure was predicted in silico using SWISS-Model. Results: Isolated Disintegrin_Cc induced deep morphological alterations on the parasites and a strong anti-leishmanial activity estimated to 84.75% of mortality. SDS-PAGE analysis indicated that this disintegrin was homogenous. This dimeric disintegrin of 14,193.97 Da contains an RGD domain and four intramolecular disulfide bridges. This biomolecule presents a high percentage of identity with other related types of snake disintegrin. Predicted 3D structure indicated that this peptide shares partial homology with well-known active antimicrobial peptides. Conclusion: This study demonstrated the leishmanicidal activity of Disintegrin_Cc. This molecule may be useful to design a new therapy against leishmaniasis.

  • molecular modeling biochemical characterization and pharmacological properties of cc3 spase a platelet aggregating thrombin like enzyme purified from Cerastes Cerastes venom
    Journal of Biochemical and Molecular Toxicology, 2018
    Co-Authors: Fatah Cherifi, Samah Saoud, Fatima Larabadjebari
    Abstract:

    Cc3 -SPase (30 kDa-proteinase; pI 5.98) was isolated from Cerastes Cerastes venom. Its sequence of 271 residues yielded from LC-MALDI-TOF showed high degrees of homology when aligned with other proteinases. Cc3 -SPase cleaved natural and synthetic proteins such as casein and fibrinogen leaving fibrin clots unaffected. Cc3 -SPase was fully abolished by ion chelators, whereas aprotinin, antithrombin III (Sigma Aldrich, Saint-Louis, Missouri, USA), and heparin were ineffective. Affinity of Cc3 -SPase to benzamidine indicated the presence of an aspartate residue in the catalytic site as confirmed by three-dimensional structure consisting of 14 β-strands and four α-helices. Molecular mechanisms revealed that Cc3 -SPase is capable of promoting dysfunctional platelet aggregation via two signaling pathways mediated by the G-coupled protein receptors and αIIbβ3 integrin. Cc3 -SPase is involved in both extrinsic/intrinsic coagulation pathways in deficient plasmas by replacing defective/lacking factors FII, FVII, and FVIII but not FX. Cc3 -SPase could substitute missing factors in blood diseases related to plasma factor deficiencies.

Naziha Marrakchi - One of the best experts on this subject based on the ideXlab platform.

  • Antitumoral potential of tunisian snake venoms secreted phospholipases A2.
    BioMed Research International, 2013
    Co-Authors: Raoudha Zouari-kessentini, Amine Bazaa, Mohamed El Ayeb, Jose Luis, Najet Srairi-abid, Naziha Marrakchi
    Abstract:

    Phospholipases type A2 (PLA2s) are the most abundant proteins found in Viperidae snake venom. They are quite fascinating from both a biological and structural point of view. Despite similarity in their structures and common catalytic properties, they exhibit a wide spectrum of pharmacological activities. Besides being hydrolases, secreted phospholipases A2 (sPLA2) are an important group of toxins, whose action at the molecular level is still a matter of debate. These proteins can display toxic effects by different mechanisms. In addition to neurotoxicity, myotoxicity, hemolytic activity, antibacterial, anticoagulant, and antiplatelet effects, some venom PLA2s show antitumor and antiangiogenic activities by mechanisms independent of their enzymatic activity. This paper aims to discuss original finding against anti-tumor and anti-angiogenic activities of sPLA2 isolated from Tunisian vipers: Cerastes Cerastes and Macrovipera lebetina, representing new tools to target specific integrins, mainly, α5β1 and αv integrins.

  • CC-PLA2-1 and CC-PLA2-2, two Cerastes Cerastes venom-derived phospholipases A2, inhibit angiogenesis both in vitro and in vivo.
    Laboratory Investigation, 2010
    Co-Authors: Raoudha Kessentini-zouari, Mohamed El Ayeb, Jacques Marvaldi, Olfa Kallech-ziri, Najet Srairi-abid, Sofiane Bezzine, Jed Jebali, Maram Morjen, Salma Taboubi, Naziha Marrakchi
    Abstract:

    Integrins are essential in the complex multistep process of angiogenesis and are thus attractive targets for the development of antiangiogenic therapies. Integrins are antagonized by disintegrins and C-type lectin-like proteins, two protein families from snake venom. Here, we report that CC-PLA2-1 and CC-PLA2-2, two novel secreted phospholipases A(2) (PLA(2)) isolated from Cerastes Cerastes venom, also showed anti-integrin activity. Indeed, both PLA(2)s efficiently inhibited human brain microvascular endothelial cell adhesion and migration to fibrinogen and fibronectin in a dose-dependent manner. Interestingly, we show that this anti-adhesive effect was mediated by alpha5beta1 and alphav-containing integrins. CC-PLA2s also impaired in vitro human brain microvascular endothelial cell tubulogenesis on Matrigel and showed antiangiogenic activity in vivo in chicken chorioallantoic membrane assay. The complete PLA(2) cDNAs were cloned from a venom gland cDNA library. Mature CC-PLA2-1 and CC-PLA2-2 contain 121 and 120 amino acids, respectively, including 14 cysteines each and showed 83% identity. Tertiary model structures of CC-PLA2-1 and CC-PLA2-2 were generated by homology modeling. This is thus the first study describing an antiangiogenic effect for snake venom PLA(2)s and reporting first clues to their mechanism of action on endothelial cells.

  • Two purified and characterized phospholipases A2 from Cerastes Cerastes venom, that inhibit cancerous cell adhesion and migration.
    Toxicon, 2009
    Co-Authors: Raoudha Zouari-kessentini, Amine Bazaa, Mohamed El Ayeb, Jose Luis, Aida Karray, Olfa Kallech-ziri, Najet Srairi-abid, Erwann Loret, Sofiane Bezzine, Naziha Marrakchi
    Abstract:

    Two non-toxic PLA2s were purified to homogeneity from Cerastes Cerastes Tunisian snake venom. The purification process employed gel filtration on Sephadex G-75 followed by C18 reverse phase high-pressure liquid chromatography. These two acidic enzymes, namely CC-PLA2-1 and CC-PLA2-2, have a molecular weight of 13,737.52 and 13,705.63 Da, respectively. These two PLA2 are the first reported glycosylated phospholipases A2 purified from snake venom. The rates of glycosylation are 2.5% and 0.5% (w/w), respectively. Specific activities of 1800 U/mg and 2400 U/mg for CC-PLA2-1 and CC-PLA2-2, respectively, were measured at optimal conditions. CC-PLA2-1 and CC-PLA2-2 strongly inhibited coagulation. They also exhibited a marked dose-dependent inhibitory effect on platelet aggregation induced by ADP and arachidonic acid in platelet-rich plasma. Interestingly, CC-PLA2-1 and CC-PLA2-2 inhibited in a dose-dependent manner adhesion of IGR39 melanoma and HT1080 fibrosarcoma cells to fibrinogen and fibronectin. Furthermore, both CC-PLA2-1 and CC-PLA2-2 abolished HT1080 cell migration towards fibrinogen and fibronectin. This activity is reported for the first time for PLA2 enzymes.

  • snake venomics comparative analysis of the venom proteomes of the tunisian snakes Cerastes Cerastes Cerastes vipera and macrovipera lebetina
    Proteomics, 2005
    Co-Authors: Amine Bazaa, Mohamed El Ayeb, Naziha Marrakchi, Libia Sanz, Juan J. Calvete
    Abstract:

    : The protein composition of the crude venoms of the three most important vipers of Tunisia was analyzed by RP-HPLC, N-terminal sequence analysis, MALDI-TOF mass determination, and in-gel tryptic digestion followed by PMF and CID-MS/MS of selected peptide ions in a quadrupole-linear IT instrument. Our results show that the venom proteomes of Cerastes Cerastes, Cerastes vipera, and Macrovipera lebetina are composed of proteins belonging to a few protein families. However, each venom showed distinct degree of protein composition complexity. The three venoms shared a number of protein classes though the relative occurrence of these toxins was different in each snake species. On the other hand, the venoms of the Cerastes species and Macrovipera lebetina each contained unique components. The comparative proteomic analysis of Tunisian snake venoms provides a comprehensible catalogue of secreted proteins, which may contribute to a deeper understanding of the biological effects of the venoms, and may also serve as a starting point for studying structure-function correlations of individual toxins.

  • Molecular Cloning and Expression of a Functional Snake Venom Serine Proteinase, with Platelet Aggregating Activity, from the Cerastes Cerastes Viper
    Biochemistry, 2003
    Co-Authors: Hafedh Dekhil, Mohamed El Ayeb, Naziha Marrakchi, Cassian Bon, Anne Wisner, Habib Karoui
    Abstract:

    The venoms of Viperidae snakes contain numerous serine proteinases that have been recognized to possess one or more of the essential activities of thrombin on fibrinogen and platelets. Among them, a platelet proaggregant protein, cerastocytin, has been isolated from the venom of the Tunisian viper Cerastes Cerastes. Using the RACE-PCR technique, we isolated and identified the complete nucleotide sequence of a cDNA serine proteinase precursor. The recombinant protein was designated rCC-PPP (for C. Cerastes platelet proaggregant protein), since its deduced amino acid sequence is more than 96% identical to the partial polypeptide sequences that have been determined for natural cerastocytin. The structure of the rCC-PPP cDNA is similar to that of snake venom serine proteinases. The expression of rCC-PPP in Escherichia coli system allowed, for the first time, the preparation and purification of an active protein from snake venom with platelet proaggregant and fibrinogenolytic activities. Purified rCC-PPP efficiently activates blood platelets at nanomolar (8 nM) concentrations, as do natural cerastocytin (5 nM) and thrombin (1 nM). It is able to clot purified fibrinogen and to hydrolyze alpha-chains. Thus, rCC-PPP could be therefore considered a cerastocytin isoform. By comparison with other snake venom serine proteinases, a Gly replaces the conserved Cys(42). This implies that rCC-PPP lacks the conserved Cys(42)-Cys(58) disulfide bridge. A structural analysis performed by molecular modeling indicated that the segment of residues Tyr(67)-Arg(80) of rCC-PPP corresponds to anion-binding exosite 1 of thrombin that is involved in its capacity to induce platelet aggregation. Furthermore, the surface of the rCC-PPP molecule is characterized by a hydrophobic pocket, comprising the 90 loop (Phe(90)-Val(99)), Tyr(172), and Trp(215) residues, which might be involved in the fibrinogen clotting activity of rCC-PPP.

Mohamed El Ayeb - One of the best experts on this subject based on the ideXlab platform.

  • Antitumoral potential of tunisian snake venoms secreted phospholipases A2.
    BioMed Research International, 2013
    Co-Authors: Raoudha Zouari-kessentini, Amine Bazaa, Mohamed El Ayeb, Jose Luis, Najet Srairi-abid, Naziha Marrakchi
    Abstract:

    Phospholipases type A2 (PLA2s) are the most abundant proteins found in Viperidae snake venom. They are quite fascinating from both a biological and structural point of view. Despite similarity in their structures and common catalytic properties, they exhibit a wide spectrum of pharmacological activities. Besides being hydrolases, secreted phospholipases A2 (sPLA2) are an important group of toxins, whose action at the molecular level is still a matter of debate. These proteins can display toxic effects by different mechanisms. In addition to neurotoxicity, myotoxicity, hemolytic activity, antibacterial, anticoagulant, and antiplatelet effects, some venom PLA2s show antitumor and antiangiogenic activities by mechanisms independent of their enzymatic activity. This paper aims to discuss original finding against anti-tumor and anti-angiogenic activities of sPLA2 isolated from Tunisian vipers: Cerastes Cerastes and Macrovipera lebetina, representing new tools to target specific integrins, mainly, α5β1 and αv integrins.

  • CC-PLA2-1 and CC-PLA2-2, two Cerastes Cerastes venom-derived phospholipases A2, inhibit angiogenesis both in vitro and in vivo.
    Laboratory Investigation, 2010
    Co-Authors: Raoudha Kessentini-zouari, Mohamed El Ayeb, Jacques Marvaldi, Olfa Kallech-ziri, Najet Srairi-abid, Sofiane Bezzine, Jed Jebali, Maram Morjen, Salma Taboubi, Naziha Marrakchi
    Abstract:

    Integrins are essential in the complex multistep process of angiogenesis and are thus attractive targets for the development of antiangiogenic therapies. Integrins are antagonized by disintegrins and C-type lectin-like proteins, two protein families from snake venom. Here, we report that CC-PLA2-1 and CC-PLA2-2, two novel secreted phospholipases A(2) (PLA(2)) isolated from Cerastes Cerastes venom, also showed anti-integrin activity. Indeed, both PLA(2)s efficiently inhibited human brain microvascular endothelial cell adhesion and migration to fibrinogen and fibronectin in a dose-dependent manner. Interestingly, we show that this anti-adhesive effect was mediated by alpha5beta1 and alphav-containing integrins. CC-PLA2s also impaired in vitro human brain microvascular endothelial cell tubulogenesis on Matrigel and showed antiangiogenic activity in vivo in chicken chorioallantoic membrane assay. The complete PLA(2) cDNAs were cloned from a venom gland cDNA library. Mature CC-PLA2-1 and CC-PLA2-2 contain 121 and 120 amino acids, respectively, including 14 cysteines each and showed 83% identity. Tertiary model structures of CC-PLA2-1 and CC-PLA2-2 were generated by homology modeling. This is thus the first study describing an antiangiogenic effect for snake venom PLA(2)s and reporting first clues to their mechanism of action on endothelial cells.

  • Two purified and characterized phospholipases A2 from Cerastes Cerastes venom, that inhibit cancerous cell adhesion and migration.
    Toxicon, 2009
    Co-Authors: Raoudha Zouari-kessentini, Amine Bazaa, Mohamed El Ayeb, Jose Luis, Aida Karray, Olfa Kallech-ziri, Najet Srairi-abid, Erwann Loret, Sofiane Bezzine, Naziha Marrakchi
    Abstract:

    Two non-toxic PLA2s were purified to homogeneity from Cerastes Cerastes Tunisian snake venom. The purification process employed gel filtration on Sephadex G-75 followed by C18 reverse phase high-pressure liquid chromatography. These two acidic enzymes, namely CC-PLA2-1 and CC-PLA2-2, have a molecular weight of 13,737.52 and 13,705.63 Da, respectively. These two PLA2 are the first reported glycosylated phospholipases A2 purified from snake venom. The rates of glycosylation are 2.5% and 0.5% (w/w), respectively. Specific activities of 1800 U/mg and 2400 U/mg for CC-PLA2-1 and CC-PLA2-2, respectively, were measured at optimal conditions. CC-PLA2-1 and CC-PLA2-2 strongly inhibited coagulation. They also exhibited a marked dose-dependent inhibitory effect on platelet aggregation induced by ADP and arachidonic acid in platelet-rich plasma. Interestingly, CC-PLA2-1 and CC-PLA2-2 inhibited in a dose-dependent manner adhesion of IGR39 melanoma and HT1080 fibrosarcoma cells to fibrinogen and fibronectin. Furthermore, both CC-PLA2-1 and CC-PLA2-2 abolished HT1080 cell migration towards fibrinogen and fibronectin. This activity is reported for the first time for PLA2 enzymes.

  • snake venomics comparative analysis of the venom proteomes of the tunisian snakes Cerastes Cerastes Cerastes vipera and macrovipera lebetina
    Proteomics, 2005
    Co-Authors: Amine Bazaa, Mohamed El Ayeb, Naziha Marrakchi, Libia Sanz, Juan J. Calvete
    Abstract:

    : The protein composition of the crude venoms of the three most important vipers of Tunisia was analyzed by RP-HPLC, N-terminal sequence analysis, MALDI-TOF mass determination, and in-gel tryptic digestion followed by PMF and CID-MS/MS of selected peptide ions in a quadrupole-linear IT instrument. Our results show that the venom proteomes of Cerastes Cerastes, Cerastes vipera, and Macrovipera lebetina are composed of proteins belonging to a few protein families. However, each venom showed distinct degree of protein composition complexity. The three venoms shared a number of protein classes though the relative occurrence of these toxins was different in each snake species. On the other hand, the venoms of the Cerastes species and Macrovipera lebetina each contained unique components. The comparative proteomic analysis of Tunisian snake venoms provides a comprehensible catalogue of secreted proteins, which may contribute to a deeper understanding of the biological effects of the venoms, and may also serve as a starting point for studying structure-function correlations of individual toxins.

  • Molecular Cloning and Expression of a Functional Snake Venom Serine Proteinase, with Platelet Aggregating Activity, from the Cerastes Cerastes Viper
    Biochemistry, 2003
    Co-Authors: Hafedh Dekhil, Mohamed El Ayeb, Naziha Marrakchi, Cassian Bon, Anne Wisner, Habib Karoui
    Abstract:

    The venoms of Viperidae snakes contain numerous serine proteinases that have been recognized to possess one or more of the essential activities of thrombin on fibrinogen and platelets. Among them, a platelet proaggregant protein, cerastocytin, has been isolated from the venom of the Tunisian viper Cerastes Cerastes. Using the RACE-PCR technique, we isolated and identified the complete nucleotide sequence of a cDNA serine proteinase precursor. The recombinant protein was designated rCC-PPP (for C. Cerastes platelet proaggregant protein), since its deduced amino acid sequence is more than 96% identical to the partial polypeptide sequences that have been determined for natural cerastocytin. The structure of the rCC-PPP cDNA is similar to that of snake venom serine proteinases. The expression of rCC-PPP in Escherichia coli system allowed, for the first time, the preparation and purification of an active protein from snake venom with platelet proaggregant and fibrinogenolytic activities. Purified rCC-PPP efficiently activates blood platelets at nanomolar (8 nM) concentrations, as do natural cerastocytin (5 nM) and thrombin (1 nM). It is able to clot purified fibrinogen and to hydrolyze alpha-chains. Thus, rCC-PPP could be therefore considered a cerastocytin isoform. By comparison with other snake venom serine proteinases, a Gly replaces the conserved Cys(42). This implies that rCC-PPP lacks the conserved Cys(42)-Cys(58) disulfide bridge. A structural analysis performed by molecular modeling indicated that the segment of residues Tyr(67)-Arg(80) of rCC-PPP corresponds to anion-binding exosite 1 of thrombin that is involved in its capacity to induce platelet aggregation. Furthermore, the surface of the rCC-PPP molecule is characterized by a hydrophobic pocket, comprising the 90 loop (Phe(90)-Val(99)), Tyr(172), and Trp(215) residues, which might be involved in the fibrinogen clotting activity of rCC-PPP.

Larabadjebari Fatima - One of the best experts on this subject based on the ideXlab platform.

  • CcMP-II Metalloproteinase from Cerastes Cerastes Snake Venom Acts both on Blood Vessel ECM and Platelets
    'Knowledge Kingdom Publishing', 2020
    Co-Authors: Bennacer Amel, Boukhalfa-abib Hinda, Larabadjebari Fatima
    Abstract:

    Background: Snake venoms contain various metalloproteinases that are highly toxic, inducing in severe bleeding by interfering with the blood coagulation and degrading the basement membrane or extracellular matrix (ECM) components. It has been suggested that hemorrhagic metalloproteinases interact in a specific way with platelet surface proteins resulting in an alteration of platelet function.  Hemorrhage and tissue necrosis are common manifestations of viperid envenomations in humans, largely due to the actions of prominent metalloproteinases. CcMP-II a weakly hemorrhagic metalloproteinase purified from Cerastes Cerastes venom, as already described it belongs to the class P-II snake venom metalloproteinase. Methods: In this study, we characterized the biological effects of CcMP-II, including the ability of the enzyme to hydrolyze extracellular matrix components and plasma proteins, as well as its histopathological effects induced in capillaries. Then a study of the anti-aggregating activity was carried out and controlled for 10 min using a Chronolog aggregometer (ServiBIO) (USTHB, Faculty of Biological Sciences, BP 32, El-Alia Bab Ezzouar, 16111, Algiers, Algeria in 2019). The histopathological changes induced by CcMP-II were also analyzed and the 1 µm semi-thin sections are then stained with Toluidine Blue and the observation of these sections was realized using a photomicroscope. Toluidine Blue, magnification: 100x. Results: Obtained results showed that CcMP-II metalloproteinase hydrolyzed selectively the A α-chain of fibrinogen. This enzyme hydrolyzed also laminin and type IV collagen in time- and dose-dependent manner. CcMP-II inhibits collagen-induced platelet aggregation of human PRP with an IC50 value of 0.11 nM.  Pathological changes induced by CcMP-II after intramuscular injection in mice gastrocnemius were also studied. Histological study showed that the main morphological alterations in capillary vessels are characterized by a separation of endothelial cells from the surrounding basement membrane and reduction in the width of these cells, together with loss of basement membrane in some areas, through which erythrocytes and plasma are extravasated. Conclusion: In conclusion, CcMP-II, as a member of the P-II class of SVMPs, presents a selective specificity toward fibrinogen, laminin and type IV collagen. It was an α- fibrinogenase metalloproteinase, which inhibits collagen-stimulated platelet aggregation. This study will contribute to understanding better the functional mechanisms of the metalloproteinases that may be useful in the development of therapeutic agents related to thrombotic disorders

  • antiplatelet and anticoagulant activities of two phospholipase a2s purified from Cerastes Cerastes venom structure function relationship
    Journal of Biochemical and Molecular Toxicology, 2018
    Co-Authors: Cherifi Fatah, Saoud Samah, Larabadjebari Fatima
    Abstract:

    This study aimed to elucidate anticoagulant/antiplatelet mechanisms of two previously purified PLA2 s from Cerastes Cerastes venom, here, termed Cc1 -PLA2 and Cc2 -PLA2 . Both PLA2 s present close molecular weights of 13,534 and 13,430 Da and Isoectric pH (pI) 7.38 and 7.86 respectively, for Cc1 -PLA2 and Cc2 -PLA2 . These Ca2+ -dependent enzymes showed a high catalytic activity upon phospholipids, inducing indirect hemolysis, since they conserve the catalytic domain of PLA2 s 26 CYCGWGGKG34 . They exhibited dual inhibition of platelet aggregation by targeting P2 Y12 and TPα receptors preventing Adenosine diphosphate/arachidonate binding and blood clotting. These effects are due to the interaction of Cc1 -PLA2 s/Cc2 -PLA2 s with factor FXa through a noncatalytic PL-independent mechanism leading to nonreleased thrombin. Both proteins consist of 120 amino acid residues and share similar three-dimensional structures close to other SV-PLA2 s. Structural data of PLA2 s allowed the relevant residues involved in binding to FXa and platelet receptors. These findings may lead to the design of novel noncompetitive FXa inhibitors.

  • Isolation and characterization of an anti-leishmanial disintegrin from Cerastes Cerastes venom
    'Wiley', 2018
    Co-Authors: Allane Dihia, Oussedik-oumehdi Habiba, Harrat Zoubir, Seve Michel, Larabadjebari Fatima
    Abstract:

    International audienceInvestigating new antimicrobial and antiparasitic components from Viperidae venoms represents an alternative therapeutic strategy. In this study, we report the characterization of a disintegrin isolated from Cerastes Cerastes venom, exhibiting antiparasitic activity on Leishmania infantum promastigotes. Indeed, isolated disintegrin, referred to Disintegrin_Cc, induced 84.75% of parasiticidal activity and deep morphological alterations on the parasites. SDS-PAGE analysis indicated that this disintegrin was homogenous. This dimeric disintegrin of 14,193.97 Da contains an RGD domain and four intramolecular disulfide bridges. It presents a high percentage of identity with other related snake disintegrins. Predicted 3D structure indicated that this peptide shares partial homology with well-known active antimicrobial peptides. Disintegrin_Cc inhibited 80% of arachidonic acid-induced platelet aggregation. The obtained results suggest that the isolated molecule plays a dual role as a disintegrin and as an anti-leishmanial compound. This component could be useful as a drug in the treatment of leishmaniasis

  • purification and characterization of cc lec c type lactose binding lectin a platelet aggregation and blood clotting inhibitor from Cerastes Cerastes venom
    International Journal of Biological Macromolecules, 2017
    Co-Authors: Saoud Samah, Cherifi Fatah, Berjeaud Jeanmarc, Kelloutairi Safia, Larabadjebari Fatima
    Abstract:

    Abstract In this study, we reported for the first time the biochemical and structural characterization of Cc-Lec, a C-type lectin purified from Cerastes Cerastes venom by affinity chromatography. This lectin was homogeneous by SDS-PAGE, and was shown to be a 34 271.59 Da polypeptide by Electrospray mass spectrometry MS-ES-TOF. Its identified sequence of 160 amino acids corresponding to one subunit, revealed a high identity with other related proteins. Cc-Lec modeled 3D structure appeared as homodimer cross-linked by one disulfide bridge. Cc-Lec exhibited a calcium dependent hemagglutinating activity against human group O erythrocytes. Cc-Lec inhibited platelet aggregation induced by ADP, arachidonic acid or fibrinogen suggesting its interaction with their specific receptors namely P2Y1 and/or P2Y12, GPIIb/IIIa and TPα respectively. Cc-Lec was not lethal for mice until 10 mg/kg administered by i.p. route. The lectin displayed a lasting anticoagulation on mice plasma even two days post-injection. This anticoagulation seems to be related to its interaction with coagulation factors Xa and IXa. Therefore, Cc-Lec prevented FXa amidolytic activity with K m = 4.33 10 −4  μg/mL and k i = 14.4 μg/mL. It seems to interact with these targets through CRD domain which could make it a good target as a pharmacological promising molecule in thrombosis diagnosis and therapy.

  • purification characterization and antibacterial activity of l amino acid oxidase from Cerastes Cerastes
    Journal of Biochemical and Molecular Toxicology, 2014
    Co-Authors: Ziadmeziane Hananefadila, Larabadjebari Fatima
    Abstract:

    Antibiotic resistance presents a real problem in which new antibacterial molecules from natural secretions could be beneficial in the development of new drugs. In this study, Cerastes Cerastes venom was investigated for its antibacterial activity against Gram-positive and Gram-negative bacteria. The antibacterial activity was evaluated by measuring the halo inhibition and minimum inhibitory concentration (MIC). An L-amino acid oxidase (CcLAAO) was purified from this venom using three chromatographic steps; its homogeneity (60 kDa) was confirmed by SDS-PAGE. LC-MS/MS analysis of CcLAAO showed similarities with other LAAO enzymes from Echis ocellatus and Viridovipera stejnegeri venoms. CcLAAO presents an antibacterial activity against three bacterial strains (Staphylococcus aureus, Methicillin-resistant S. aureus, and Pseudomonas aeruginosa) with MIC values of 10, 10, and 20 μg/mL, respectively. However, no effect was observed against Escherichia coli and yeast strains. Kinetic parameters of CcLAAO evaluated on L-leucine at pH 8.0 and 20°C were Km = 0.06 mmol and Vmax = 164 mmol/min.

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  • rosemary leaves extract anti snake action against egyptian Cerastes Cerastes venom
    Journal of Traditional and Complementary Medicine, 2018
    Co-Authors: Walaa H. Salama, Azza M Abdelaty, Afaf S. Fahmy
    Abstract:

    Abstract The morbidity caused by viper bites is very dangerous and the anti-venom therapy couldn't treat the local injures such as hemorrhage, edema, necrosis and inflammation of bitten tissues. Searching for safe and effective anti-venom compounds from natural sources is very important. This study was designed to explore the neutralizing ability of Rosmarinus officinalis L. leaves aqueous extract (RMAE) against Egyptian Cerastes Cerastes (Cc) viper venom toxicity. The RMAE contained a considerable amount of phenolic and flavonoid contents with 3,300 and 800 mg/100 g dry weight, respectively. The RMAE showed a considerable variation of phenolic acids by using HPLC technique. Rosmarinic acid is the major component of the RMAE which recorded 400 mg/100 g dry weight and 64% of all the identified compounds. In vitro, the RMAE neutralized the enzymatic activities of proteases, l -amino acid oxidases, and phospholipases A2 of the Cc venom dose-dependently. In addition, the RMAE effectively neutralized the gelatinolytic, fibrinogenolytic, hemolytic and procoagulant activities of Cc venom. In vivo, the RMAE markedly reduced lethality, hemorrhage, edema, muscle and liver toxicities induced by Cc venom. In conclusion, the venom neutralizing property of the RMAE gives a new prospect for efficient treatment of the lethal viper bites.

  • Rosemary leaves extract: Anti-snake action against Egyptian Cerastes Cerastes venom
    Elsevier, 2018
    Co-Authors: Walaa H. Salama, Azza M. Abdel-aty, Afaf S. Fahmy
    Abstract:

    The morbidity caused by viper bites is very dangerous and the anti-venom therapy couldn't treat the local injures such as hemorrhage, edema, necrosis and inflammation of bitten tissues. Searching for safe and effective anti-venom compounds from natural sources is very important. This study was designed to explore the neutralizing ability of Rosmarinus officinalis L. leaves aqueous extract (RMAE) against Egyptian Cerastes Cerastes (Cc) viper venom toxicity. The RMAE contained a considerable amount of phenolic and flavonoid contents with 3,300 and 800 mg/100 g dry weight, respectively. The RMAE showed a considerable variation of phenolic acids by using HPLC technique. Rosmarinic acid is the major component of the RMAE which recorded 400 mg/100 g dry weight and 64% of all the identified compounds. In vitro, the RMAE neutralized the enzymatic activities of proteases, l-amino acid oxidases, and phospholipases A2 of the Cc venom dose-dependently. In addition, the RMAE effectively neutralized the gelatinolytic, fibrinogenolytic, hemolytic and procoagulant activities of Cc venom. In vivo, the RMAE markedly reduced lethality, hemorrhage, edema, muscle and liver toxicities induced by Cc venom. In conclusion, the venom neutralizing property of the RMAE gives a new prospect for efficient treatment of the lethal viper bites. Keywords: Cerastes Cerastes, Venom, Enzymes, Lethality, Rosmarinus officinalis L., Neutralizatio

  • Phenolic-antioxidant capacity of mango seed kernels: therapeutic effect against viper venoms
    Elsevier, 2018
    Co-Authors: Azza M. Abdel-aty, Walaa H. Salama, Afaf S. Fahmy, Mohamed Belal Hamed, Saleh A. Mohamed
    Abstract:

    In this study, mango seed kernels extract contained a considerable amount of phenolics and flavonoids (17,400 and 3325 mg/100 g seed, respectively). The HPLC profiling revealed that hesperidin was the major phenolic compound of the mango seed kernels extract. This is the first report find hesperidin in mango extracts. The phenolic compounds of mango seed kernels extract were effective in scavenging free radicals of DPPH and ABTS with IC50 values of 47.3 and 7.9 μg/ml, respectively. The total antioxidant activity of mango seed kernels extract based on the reduction of molybdenum was also measured. The phenolic compounds of mango seed kernels extract potentially inhibited the protease, fibrinogenase, phospholipase A2, l-amino acid oxidase, hyaluronidase, and hemolytic activities of the most dangerous Cerastes Cerastes and Echis coloratus viper venoms. The phenolic compounds of mango seed kernels extract could completely neutralize the hemorrhage and lethality of both venoms in experimental animals. It could be concluded that the mango seed kernels extract phenolic compounds with potential antioxidant activity are considered as a new avenue in the viper bite treatment. Keywords: Antioxidant, Anti-venom, Egyptian mango, Oxidative stress, Phenolic compound

  • egyptian horned viper Cerastes Cerastes venom hyaluronidase purification partial characterization and evidence for its action as a spreading factor
    Toxicon, 2012
    Co-Authors: Af Wahby, Walaa H. Salama, Azza M Abdelaty, Elsayed M E Mahdy, Hatem A Elmezayen, Afaf S. Fahmy
    Abstract:

    Novel Hyaluronidase CcHaseII (33 kDa) of the most dangerous horned viper Cerastes Cerastes (Cc) was purified and partial characterized in a set of biochemical assays. CcHaseII was purified by applying a protocol of two successive chromatographic steps; gel filtration on a Sephacryl S-200 and cation exchange chromatography on CM-Sepharose columns. It has specific activity 4000 units/mg protein against 154 units/mg protein for the whole venom with 26-purification fold. The enzymatic activity of the purified Hyaluronidase stimulated by Na+ and inhibited by entire tested cations, metalloproteinase inhibitors and heparin. CcHaseII (5–10 μg) enhanced one hundred percent of hemorrhagic activity of the potent purified hemorrhagic SVMP of corresponding venom (CcHTI) and enhanced edema-inducing activity of Cc venom in a dose-dependent manner. Furthermore, the described purification procedure allows simple preparation of appreciable quantities of the CcHaseII for further studies. Eventually, exploration of snake venom antigenic parts is the most crucial factor for establishing good immunogens and specific diagnostic reagents.

  • role of hyaluronidase inhibitors in the neutralization of toxicity of egyptian horned viper Cerastes Cerastes venom
    Journal of Genetic Engineering and Biotechnology, 2012
    Co-Authors: Af Wahby, Walaa H. Salama, Azza M Abdelaty, Elsayed M E Mahdy, Hatem A Elmezayen, Nihal M Ebrahim, Afaf S. Fahmy
    Abstract:

    Abstract Hyaluronidase “venom spreading factor” is a common component of snake venoms and indirectly potentiates venom toxicity. It may cause permanent local tissue destruction at the bite site/systemic collapse of the envenomated victim. The present study was performed to assess the benefits of inhibiting the hyaluronidase activity of Egyptian horned viper, Cerastes Cerastes (Cc). The aqueous extracts of some medicinal plants were screened for their inhibitory effect on hyaluronidase activity of Cc venom. The results revealed that the Rosmarinus officinalis (Ro) extract is the most potent hyaluronidase inhibitor among the tested extracts. The Ro extract is more potent inhibitory effect on the hyaluronidase activity than the prepared rabbit monoclonal antiserum of previously purified hyaluronidase enzyme from Cc venom (anti-CcHaseII). In addition, the Ro extract is efficiently inhibited the activity of hemorrhagic toxin previously purified from Cc venom, and it also neutralized the edema inducing activity of the Cc venom in vivo . Furthermore, the Ro extract markedly increased the survival time of experimental mice injected with lethal dose of Cc venom up to 7 h in compared to mice injected with venom alone or with venom/anti-CcHaseII (15 ± 5, 75 ± 4 min), respectively. Our findings imply the significance of plant-derived hyaluronidase inhibitor in the neutralization of local effects of Cc venom and retardation of death time. Therefore, it may use as a therapeutic value in complementary snakebite therapy.