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Alonazi M, Krayem N, Alharbi MG, Khayyat AIA, Alanazi H, Horchani H, Ben Bacha A. Functional Characterization and Anti-Tumor Effect of a Novel Group II Secreted Phospholipase A 2 from Snake Venom of Saudi Cerastes cerates gasperetti. Molecules 2023; 28:6517. [PMID: 37764293 PMCID: PMC10536776 DOI: 10.3390/molecules28186517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 08/31/2023] [Accepted: 09/05/2023] [Indexed: 09/29/2023] Open
Abstract
Secreted phospholipases A2 are snake-venom proteins with many biological activities, notably anti-tumor activity. Phospholipases from the same snake type but different geographical locations have shown similar biochemical and biological activities with minor differences in protein sequences. Thus, the discovery of a new phospholipase A2 with unique characteristics identified in a previously studied venom could suggest the origins of these differences. Here, a new Group II secreted phospholipase A2 (Cc-PLA2-II) from the snake venom of Saudi Cerastes cerastes gasperetti was isolated and characterized. The purified enzyme had a molecular weight of 13.945 kDa and showed high specific activity on emulsified phosphatidylcholine of 1560 U/mg at pH 9.5 and 50 °C with strict calcium dependence. Interestingly, stability in extreme pH and high temperatures was observed after enzyme incubation at several pH levels and temperatures. Moreover, a significant dose-dependent cytotoxic anti-tumor effect against six human cancer cell lines was observed with concentrations of Cc-PLA2 ranging from 2.5 to 8 µM. No cytotoxic effect on normal human umbilical-vein endothelial cells was noted. These results suggest that Cc-PLA2-II potentially has angiogenic activity of besides cytotoxicity as part of its anti-tumor mechanism. This study justifies the inclusion of this enzyme in many applications for anticancer drug development.
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Affiliation(s)
- Mona Alonazi
- Biochemistry Department, Science College, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia; (M.A.); (M.G.A.); (A.I.A.K.); (H.A.)
| | - Najeh Krayem
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS, Université de Sfax, Route de Soukra 3038, Sfax BP 1173, Tunisia;
| | - Mona G. Alharbi
- Biochemistry Department, Science College, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia; (M.A.); (M.G.A.); (A.I.A.K.); (H.A.)
| | - Arwa Ishaq A. Khayyat
- Biochemistry Department, Science College, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia; (M.A.); (M.G.A.); (A.I.A.K.); (H.A.)
| | - Humidah Alanazi
- Biochemistry Department, Science College, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia; (M.A.); (M.G.A.); (A.I.A.K.); (H.A.)
| | - Habib Horchani
- Science Department, College of Rivière-Du-Loup, Rivière-Du-Loup, QC G5R 1R1, Canada;
| | - Abir Ben Bacha
- Biochemistry Department, Science College, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia; (M.A.); (M.G.A.); (A.I.A.K.); (H.A.)
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Frihling BEF, Boleti APDA, de Oliveira CFR, Sanches SC, Cardoso PHDO, Verbisck N, Macedo MLR, Rita PHS, Carvalho CME, Migliolo L. Purification, Characterization and Evaluation of the Antitumoral Activity of a Phospholipase A2 from the Snake Bothrops moojeni. Pharmaceuticals (Basel) 2022; 15:ph15060724. [PMID: 35745643 PMCID: PMC9230114 DOI: 10.3390/ph15060724] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 04/18/2022] [Accepted: 04/19/2022] [Indexed: 12/24/2022] Open
Abstract
Nature presents a wide range of biomolecules with pharmacological potential, including venomous animal proteins. Among the protein components from snake venoms, phospholipases (PLA2) are of great importance for the development of new anticancer compounds. Thus, we aimed to evaluate the PLA2 anticancer properties from Bothrops moojeni venom. The crude venom was purified through three chromatographic steps, monitored by enzymatic activity and SDS-PAGE (12%). The purified PLA2 denominated BmPLA2 had its molecular mass and N-terminal sequence identified by mass spectrometry and Edman degradation, respectively. BmPLA2 was assayed against human epithelial colorectal adenocarcinoma cells (Caco-2), human rhabdomyosarcoma cells (RD) and mucoepidermoid carcinoma of the lung (NCI-H292), using human fibroblast cells (MRC-5) and microglia cells (BV-2) as a cytotoxicity control. BmPLA2 presented 13,836 Da and a 24 amino acid-residue homologue with snake PLA2, which showed a 90% similarity with other Bothrops moojeni PLA2. BmPLA2 displayed an IC50 of 0.6 µM against Caco-2, and demonstrated a selectivity index of 1.85 (compared to MRC-5) and 6.33 (compared to BV-2), supporting its selectivity for cancer cells. In conclusion, we describe a new acidic phospholipase, which showed antitumor activity and is a potential candidate in the development of new biotechnological tools.
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Affiliation(s)
- Breno Emanuel Farias Frihling
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande 79117-900, MS, Brazil; (B.E.F.F.); (A.P.d.A.B.); (S.C.S.); (P.H.d.O.C.); (C.M.E.C.)
| | - Ana Paula de Araújo Boleti
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande 79117-900, MS, Brazil; (B.E.F.F.); (A.P.d.A.B.); (S.C.S.); (P.H.d.O.C.); (C.M.E.C.)
| | - Caio Fernando Ramalho de Oliveira
- Faculdade de Ciências Farmacêuticas, Alimentos e Nutrição (FACFAN), Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande 79603-011, MS, Brazil; (C.F.R.d.O.); (M.L.R.M.)
| | - Simone Camargo Sanches
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande 79117-900, MS, Brazil; (B.E.F.F.); (A.P.d.A.B.); (S.C.S.); (P.H.d.O.C.); (C.M.E.C.)
| | - Pedro Henrique de Oliveira Cardoso
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande 79117-900, MS, Brazil; (B.E.F.F.); (A.P.d.A.B.); (S.C.S.); (P.H.d.O.C.); (C.M.E.C.)
| | | | - Maria Lígia Rodrigues Macedo
- Faculdade de Ciências Farmacêuticas, Alimentos e Nutrição (FACFAN), Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande 79603-011, MS, Brazil; (C.F.R.d.O.); (M.L.R.M.)
| | - Paula Helena Santa Rita
- Biotério e Serpentário, Universidade Católica Dom Bosco, Campo Grande 79117-900, MS, Brazil;
| | - Cristiano Marcelo Espinola Carvalho
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande 79117-900, MS, Brazil; (B.E.F.F.); (A.P.d.A.B.); (S.C.S.); (P.H.d.O.C.); (C.M.E.C.)
| | - Ludovico Migliolo
- S-Inova Biotech, Programa de Pós-Graduação em Biotecnologia, Universidade Católica Dom Bosco, Campo Grande 79117-900, MS, Brazil; (B.E.F.F.); (A.P.d.A.B.); (S.C.S.); (P.H.d.O.C.); (C.M.E.C.)
- Programa de Pós-Graduação em Bioquímica, Universidade Federal do Rio Grande do Norte, Natal 59078-970, RN, Brazil
- Correspondence:
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Guiding recombinant antivenom development by omics technologies. N Biotechnol 2018; 45:19-27. [DOI: 10.1016/j.nbt.2017.05.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 05/16/2017] [Indexed: 11/23/2022]
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Expression and partial biochemical characterization of a recombinant serine protease from Bothrops pauloensis snake venom. Toxicon 2016; 115:49-54. [DOI: 10.1016/j.toxicon.2016.03.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 02/15/2016] [Accepted: 03/02/2016] [Indexed: 11/22/2022]
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Zhang Y, Zhong L, Zhou B, Chen JY, Li CM. Interaction of characteristic structural elements of persimmon tannin with Chinese cobra PLA2. Toxicon 2013; 74:34-43. [PMID: 23916601 DOI: 10.1016/j.toxicon.2013.07.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 07/18/2013] [Accepted: 07/25/2013] [Indexed: 11/16/2022]
Abstract
To more fully understand the mechanism by which persimmon tannin (PT) inhibited phospholipase A2 (PLA2) and the structural requirements of PT for the inhibition, the interactions between PLA2 and seven characteristic structural elements of PT including epigallocatechin-3-gallate (EGCG), myricetin, epicatechin-3-gallate (ECG), epicatechin-3-gallate-(4β → 8, 2β → O → 7)-epicatechin-3-gallate (A-type ECG dimer), epigallocatechin-3-gallate-(4β → 8, 2β → O → 7)-epigallocatechin-3-gallate (A-type EGCG dimer), epicatechin-(4β → 8, 2β → O → 7)-epicatechin (A-type EC dimer) and epicatechin-(4β → 8)-epicatechin (B-type EC dimer) were studied by enzymatic and spectroscopic methods. Molecular docking was also used to explore the possible residues involved in the interactions. The results revealed that A-type EGCG dimer and A-type ECG dimer showed higher inhibitory effects on the catalytic activity of PLA2 than monomers and B-type dimer. They induced greater conformational changes in PLA2 than other structural elements. In addition, molecular docking studies revealed that expect for lysine residues, other residues such as Trp18, Try27, Gly29, His47 and Tyr63 were involved in the interactions. We propose that A-type EGCG and ECG dimer units may be structural requirements for the interaction between PT and PLA2. Our data provide an additional structural basis for anti-PLA2 activity of persimmon tannin.
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Affiliation(s)
- Ying Zhang
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
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dos Santos JI, Cardoso FF, Soares AM, dal Pai Silva M, Gallacci M, Fontes MRM. Structural and functional studies of a bothropic myotoxin complexed to rosmarinic acid: new insights into Lys49-PLA₂ inhibition. PLoS One 2011; 6:e28521. [PMID: 22205953 PMCID: PMC3244394 DOI: 10.1371/journal.pone.0028521] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Accepted: 11/09/2011] [Indexed: 11/18/2022] Open
Abstract
Snakebite envenoming is an important public health problem in many tropical and subtropical countries, and is considered a neglected tropical disease by the World Health Organization. Most severe cases are inflicted by species of the families Elapidae and Viperidae, and lead to a number of systemic and local effects in the victim. One of the main problems regarding viperidic accidents is prominent local tissue damage whose pathogenesis is complex and involves the combined actions of a variety of venom components. Phospholipases A₂ (PLA₂s) are the most abundant muscle-damaging components of these venoms. Herein, we report functional and structural studies of PrTX-I, a Lys49-PLA₂ from Bothops pirajai snake venom, and the influence of rosmarinic acid (RA) upon this toxin's activities. RA is a known active component of some plant extracts and has been reported as presenting anti-myotoxic properties related to bothopic envenomation. The myotoxic activity of Lys49-PLA₂s is well established in the literature and although no in vivo neurotoxicity has been observed among these toxins, in vitro neuromuscular blockade has been reported for some of these proteins. Our in vitro studies show that RA drastically reduces both the muscle damage and the neuromuscular blockade exerted by PrTX-I on mice neuromuscular preparations (by ∼80% and ∼90%, respectively). These results support the hypothesis that the two effects are closely related and lead us to suggest that they are consequences of the muscle membrane-destabilizing activity of the Lys49-PLA₂. Although the C-terminal region of these proteins has been reported to comprise the myotoxic site, we demonstrate by X-ray crystallographic studies that RA interacts with PrTX-I in a different region. Consequently, a new mode of Lys49-PLA₂ inhibition is proposed. Comparison of our results with others in the literature suggests possible new ways to inhibit bothropic snake venom myotoxins and improve serum therapy.
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Affiliation(s)
- Juliana I. dos Santos
- Departamento de Física e Biofísica, Instituto de Biociências, University Estadual Paulista, Botucatu/Sao Paulo, Brazil
- Instituto Nacional de Ciência e Tecnologia em Toxinas, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Botucatu/Sao Paulo, Brazil
| | - Fábio F. Cardoso
- Departamento de Farmacologia, Instituto de Biociências, University Estadual Paulista, Botucatu/Sao Paulo, Brazil
| | - Andreimar M. Soares
- Fundação Oswaldo Cruz - Rondônia and Centro de Estudos de Biomoléculas Aplicadas, Universidade Federal de Rondônia, Porto Velho/Rondonia, Brazil
| | - Maeli dal Pai Silva
- Departamento de Morfologia, Instituto de Biociências, University Estadual Paulista, Botucatu/Sao Paulo, Brazil
| | - Márcia Gallacci
- Departamento de Farmacologia, Instituto de Biociências, University Estadual Paulista, Botucatu/Sao Paulo, Brazil
| | - Marcos R. M. Fontes
- Departamento de Física e Biofísica, Instituto de Biociências, University Estadual Paulista, Botucatu/Sao Paulo, Brazil
- Instituto Nacional de Ciência e Tecnologia em Toxinas, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Botucatu/Sao Paulo, Brazil
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Santos-Filho NA, Fernandes CAH, Menaldo DL, Magro AJ, Fortes-Dias CL, Estevão-Costa MI, Fontes MRM, Santos CR, Murakami MT, Soares AM. Molecular cloning and biochemical characterization of a myotoxin inhibitor from Bothrops alternatus snake plasma. Biochimie 2010; 93:583-92. [PMID: 21144879 DOI: 10.1016/j.biochi.2010.11.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Accepted: 11/26/2010] [Indexed: 10/18/2022]
Abstract
Phospholipases A(2) (PLA(2)s) are important components of Bothrops snake venoms, that can induce several effects on envenomations such as myotoxicity, inhibition or induction of platelet aggregation and edema. It is known that venomous and non-venomous snakes present PLA(2) inhibitory proteins (PLIs) in their blood plasma. An inhibitory protein that neutralizes the enzymatic and toxic activities of several PLA(2)s from Bothrops venoms was isolated from Bothrops alternatus snake plasma by affinity chromatography using the immobilized myotoxin BthTX-I on CNBr-activated Sepharose. Biochemical characterization of this inhibitory protein, denominated αBaltMIP, showed it to be a glycoprotein with Mr of ~24,000 for the monomeric subunit. CD spectra of the PLA(2)/inhibitor complexes are considerably different from those corresponding to the individual proteins and data deconvolution suggests that the complexes had a relative gain of helical structure elements in comparison to the individual protomers, which may indicate a more compact structure upon complexation. Theoretical and experimental structural studies performed in order to obtain insights into the structural features of αBaltMIP indicated that this molecule may potentially trimerize in solution, thus strengthening the hypothesis previously raised by other authors about snake PLIs oligomerization.
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Affiliation(s)
- Norival A Santos-Filho
- Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, FMRP-USP, Ribeirão Preto-SP, Brazil.
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8
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Understanding the in vitro neuromuscular activity of snake venom Lys49 phospholipase A2 homologues. Toxicon 2010; 55:1-11. [DOI: 10.1016/j.toxicon.2009.10.025] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Revised: 07/22/2009] [Accepted: 10/01/2009] [Indexed: 11/24/2022]
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9
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Neutralization of Bothrops asper venom by antibodies, natural products and synthetic drugs: Contributions to understanding snakebite envenomings and their treatment. Toxicon 2009; 54:1012-28. [DOI: 10.1016/j.toxicon.2009.03.015] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2009] [Revised: 03/10/2009] [Accepted: 03/17/2009] [Indexed: 11/24/2022]
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10
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da Silva JO, Coppede JS, Fernandes VC, Sant'ana CD, Ticli FK, Mazzi MV, Giglio JR, Pereira PS, Soares AM, Sampaio SV. Antihemorrhagic, antinucleolytic and other antiophidian properties of the aqueous extract from Pentaclethra macroloba. JOURNAL OF ETHNOPHARMACOLOGY 2005; 100:145-52. [PMID: 16054531 DOI: 10.1016/j.jep.2005.01.063] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2004] [Revised: 11/03/2004] [Accepted: 01/31/2005] [Indexed: 05/03/2023]
Abstract
Several Brazilian plants have been utilized in folk medicine as active agents against various effects induced by snake venoms. The inhabitants of the Amazon region use, among others, the macerated bark of a plant popularly named "Pracaxi" (Pentaclethra macroloba Willd) to combat these effects. We report now the antihemorrhagic properties against snake venoms of the aqueous extract of Pentaclethra macroloba (EPema). EPema exhibited full inhibition of hemorrhagic and nucleolytic activities induced by several snake venoms. Additionally, partial inhibition of myotoxic, lethal, phospholipase and edema activities of snake venoms and its isolated PLA(2)s by EPema is reported. In vivo tests showed that EPema is able to totally inhibit a Bothrops jararacussu metalloprotease (BjussuMP-I) induced hemorrhage, suggesting interaction of the extract compounds with this high molecular weight protein. The extract did induce neither hemorrhage nor death in mice when administered alone by i.m. route. When administered separately by i.m. route, the extract did not induce death in mice at 12.5--300 mg/kg doses. Other assays demonstrated that EPema was unable to inhibit fibrinogenolytic and coagulant activities of Bothrops atrox venom. Although the mechanism of action of EPema is still unknown, the finding that no visible change was detected in the electrophoretic pattern of snake venom after incubation with the extract excludes proteolytic degradation as a potential mechanism. The search for new inhibitors of venom metalloproteases and DNAases are a relevant task. Investigation of snake venom inhibitors can provide useful tools for the elucidation of the action mechanisms of purified toxins. Furthermore, these inhibitors can be used as molecular models for development of new therapeutical agents in the treatment of ophidian accidents.
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Affiliation(s)
- Jocivânia O da Silva
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, FCFRP/USP, Brazil
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11
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Januário AH, Santos SL, Marcussi S, Mazzi MV, Pietro RCLR, Sato DN, Ellena J, Sampaio SV, França SC, Soares AM. Neo-clerodane diterpenoid, a new metalloprotease snake venom inhibitor from Baccharis trimera (Asteraceae): anti-proteolytic and anti-hemorrhagic properties. Chem Biol Interact 2004; 150:243-51. [PMID: 15560891 DOI: 10.1016/j.cbi.2004.09.016] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2004] [Revised: 09/23/2004] [Accepted: 09/23/2004] [Indexed: 11/29/2022]
Abstract
Many plants are used in traditional medicine as active agents against various effects induced by snakebite. Few attempts have been made however to identify the nature of plant natural products with anti-ophidian properties. Baccharis trimera (Less) DC (Asteraceae), known in Brazil as carqueja, has been popularly used to treat liver diseases, rheumatism, diabetes, as well as digestive, hepatic and renal disorders. The active component was identified as 7alpha-hydroxy-3,13-clerodadiene-16,15:18,19-diolide, C20H28O5, (clerodane diterpenoid, Bt-CD). We report now the anti-proteolytic and anti-hemorrhagic properties against snake venoms of a Bt-CD inhibitor from B. trimera. Bt-CD exhibited full inhibition of hemorrhage and proteolytic activity caused by Bothrops snake venoms. The inhibitor was able to neutralize the hemorrhagic, fibrinogenolytic and caseinolytic activities of class P-I and III metalloproteases isolated from B. neuwiedi and B. jararacussu venoms. No inhibition of the coagulant activity was observed. Bt-CD also partially inhibited the edema induced by other crude venoms, metalloproteases, basic and acidic phospholipases A2. To further elucidate the inhibitory specificity of Bt-CD against metalloproteases isolated from snake venoms, a deeper understanding of its structure and function is necessary. Furthermore, the potential use of these inhibitors to complement anti-venom as an alternative treatment of snakebite envenomations needs to be evaluated in future studies.
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Affiliation(s)
- Ana H Januário
- Unidade de Biotecnologia, Universidade de Ribeirão Preto, UNAERP, Ribeirão Preto-SP, Brazil.
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12
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Soares AM, Giglio JR. Chemical modifications of phospholipases A2 from snake venoms: effects on catalytic and pharmacological properties. Toxicon 2004; 42:855-68. [PMID: 15019487 DOI: 10.1016/j.toxicon.2003.11.004] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Phospholipases A2 (PLA2s) constitute major components of snake venoms and have been extensively investigated not only because they are very abundant in these venoms but mainly because they display a wide range of biological effects, including neurotoxic, myotoxic, cytotoxic, edema-inducing, artificial membrane disrupting, anti-coagulant, platelet aggregation inhibiting, hypotensive, bactericidal, anti-HIV, anti-tumoral, anti-malarial and anti-parasitic. Due to this functional diversity, these structurally similar proteins aroused the interest of many researchers as molecular models for study of structure-function relationships. One of the main experimental strategies used for the study of myotoxic PLA2s is the traditional chemical modification of specific amino acid residues (His, Met, Lys, Tyr, Trp and others) and examination of the consequent effects upon the enzymatic, toxic and pharmacological activities. This line of research has provided useful insights into the structural determinants of the action of these enzymes and, together with additional strategies, supports the concept of the presence of 'pharmacological sites' distinct from the catalytic site in snake venom myotoxic PLA2s.
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Affiliation(s)
- Andreimar M Soares
- Departamento de Biotecnologia, Universidade de Ribeirão Preto (UNAERP), Ribeirão Presto, SP, Brazil.
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13
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Soares AM, Sestito WP, Marcussi S, Stábeli RG, Andrião-Escarso SH, Cunha OAB, Vieira CA, Giglio JR. Alkylation of myotoxic phospholipases A2 in Bothrops moojeni venom: a promising approach to an enhanced antivenom production. Int J Biochem Cell Biol 2004; 36:258-70. [PMID: 14643891 DOI: 10.1016/s1357-2725(03)00237-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Bothrops moojeni crude venom (MjCV) and its two major toxins, namely myotoxin I (MjTX-I) and myotoxin II (MjTX-II) were alkylated by p-bromophenacyl bromide (BPB). After alkylation the i.p. LD(50) (mice) of MjCV and MjTX-I/II increased from 6.0 to 15.7mg/kg and from 8.0 to 45.0mg/kg, respectively. In addition, doses of 5x LD(50) of alkylated MjTX-I did not cause a single death in mice and no myonecrosis was detected for the alkylated toxins, although both proteins still induced edema. Antibodies to native and modified crude venom or myotoxins cross-reacted with 12 purified class II myotoxic phospholipases A(2) found in snake venoms of the genus Bothrops. Myotoxic PLA(2)s from class I and class III were not recognized by the above antibodies. These results suggest that the overall antigenic structure is conserved among class II myotoxic PLA(2)s, despite differences in their amino acid sequences. Anti-MjTX-I-BPB and anti-MjTX-II-BPB rabbit serum, obtained against the modified myotoxins, were apparently more efficient than those obtained against the native myotoxins. In neutralization experiments, pre-incubation of crude venom or isolated myotoxins with antibodies raised against the native or modified toxins inhibited their PLA(2) and myotoxic activities. Therefore, alkylation of His48 by BPB strongly reduces the local tissue damage induced by B. moojeni venom or isolated myotoxins while retaining antigenicity, which suggests a promising procedure for an enhanced antiophidian serum production for practical purposes.
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Affiliation(s)
- Andreimar M Soares
- Departamento de Biotecnologia, Universidade de Ribeirão Preto, UNAERP, SP, Ribeirão Preto, Brazil
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Lomonte B, Angulo Y, Calderón L. An overview of lysine-49 phospholipase A2 myotoxins from crotalid snake venoms and their structural determinants of myotoxic action. Toxicon 2003; 42:885-901. [PMID: 15019489 DOI: 10.1016/j.toxicon.2003.11.008] [Citation(s) in RCA: 229] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In 1984, the first venom phospholipase A2 (PLA2) with a lysine substituting for the highly conserved aspartate 49 was discovered, in the North American crotalid snake Agkistrodon p. piscivorus [J. Biol. Chem. 259 (1984) 13839]. Ten years later, the first mapping of a 'toxic region' on a Lys49 PLA2 was reported, in Bothrops asper myotoxin II [J. Biol. Chem. 269 (1994) 29867]. After a further decade of research on the Lys49 PLA2s, a better understanding of their structural determinants of toxicity and mode of action is rapidly emerging, with myotoxic effector sites identified at the C-terminal region in at least four proteins: B. asper myotoxin II, A. p. piscivorus K49 PLA2, A. c. laticinctus ACL myotoxin, and B. jararacussu bothropstoxin I. Although important features still remain to be established, their toxic mode of action has now been understood in its more general concepts, and a consistent working hypothesis can be experimentally supported. It is proposed that all the toxic activities of Lys49 PLA2s are related to their ability to destabilize natural (eukaryotic and prokaryotic) and artificial membranes, using a cationic/hydrophobic effector site located at their C-terminal loop. This review summarizes the general properties of the Lys49 PLA2 myotoxins, emphasizing the development of current concepts and hypotheses concerning the molecular basis of their toxic activities.
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Affiliation(s)
- Bruno Lomonte
- Facultad de Microbiología, Instituto Clodomiro Picado, Universidad de Costa Rica, San José, Costa Rica.
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Soares AM, Marcussi S, Stábeli RG, França SC, Giglio JR, Ward RJ, Arantes EC. Structural and functional analysis of BmjMIP, a phospholipase A2 myotoxin inhibitor protein from Bothrops moojeni snake plasma. Biochem Biophys Res Commun 2003; 302:193-200. [PMID: 12604331 DOI: 10.1016/s0006-291x(03)00155-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A protein, which neutralizes the enzymatic, toxic, and pharmacological activities of various basic and acidic phospholipases A(2) from the venoms of Bothrops moojeni, Bothrops pirajai, and Bothrops jararacussu, was isolated from B. moojeni snake plasma by affinity chromatography using immobilized myotoxins on Sepharose gel. Biochemical characterization of this myotoxin inhibitor protein (BmjMIP) showed it to be an oligomeric glycoprotein with a M(r) of 23,000-25,000 for the monomeric subunit. BmjMIP was stable in the pH range from 4.0 to 12.0, between 4 and 80 degrees C, even after deglycosylation. The role of the carbohydrate moiety was investigated and found not to affect the in vitro function of the inhibitor. The corresponding 500bp cDNA obtained by RT-PCR from the liver of the snake encodes a mature protein of 166 amino acid residues including a 19 amino acid signal peptide. The primary structure of BmjMIP showed a high similarity with other snake phospholipase A(2) inhibitors (PLIs) in which the carbohydrate recognition domain (CRD) and the glycosylation site (Asn103) are conserved. Circular dichroism spectroscopy indicated that no significant alterations in the secondary structure of either the BmjMIP or the target protein occur upon their interaction. BmjMIP has a wide range of inhibitory properties against basic and acidic PLA(2)s from Bothrops venoms (anti-enzymatic, anti-myotoxic, anti-edema inducing, anti-cytotoxic, anti-bactericidal, and anti-lethal). However, the inhibitor showed a reduced ability to neutralize the biological activities of crotoxin B (CB), the PLA(2) homologue associated with crotapotin in Crotalus durissus terrificus snake venom. Finally, the purified PLA(2) inhibitor was shown to protect in vivo against the toxic and pharmacological effects of a homologous PLA(2) enzyme, suggesting that PLIs or a corresponding derived peptide may prove useful in the treatment of snakebite victims or, more importantly, in the treatment of the many human diseases in which these enzymes have been implicated.
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Affiliation(s)
- Andreimar M Soares
- Departamento de Biotecnologia, Universidade de Ribeirão Preto, UNAERP, Ribeirão Preto, SP, Brazil.
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