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Functional and structural studies of a Phospholipase A2-like protein complexed to zinc ions: Insights on its myotoxicity and inhibition mechanism. Biochim Biophys Acta Gen Subj 2017; 1861:3199-3209. [DOI: 10.1016/j.bbagen.2016.08.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 08/05/2016] [Accepted: 08/10/2016] [Indexed: 12/28/2022]
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2
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Corrêa EA, Kayano AM, Diniz-Sousa R, Setúbal SS, Zanchi FB, Zuliani JP, Matos NB, Almeida JR, Resende LM, Marangoni S, da Silva SL, Soares AM, Calderon LA. Isolation, structural and functional characterization of a new Lys49 phospholipase A2 homologue from Bothrops neuwiedi urutu with bactericidal potential. Toxicon 2016; 115:13-21. [DOI: 10.1016/j.toxicon.2016.02.021] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Revised: 02/16/2016] [Accepted: 02/24/2016] [Indexed: 11/16/2022]
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Fernandes CA, Borges RJ, Lomonte B, Fontes MR. A structure-based proposal for a comprehensive myotoxic mechanism of phospholipase A2-like proteins from viperid snake venoms. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1844:2265-76. [DOI: 10.1016/j.bbapap.2014.09.015] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Revised: 09/09/2014] [Accepted: 09/16/2014] [Indexed: 01/21/2023]
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Taniguti APT, Matsumura CÍY, Rodrigues-Simioni LÉ, Neto HS, Marques MJ. Suramin affects metalloproteinase-9 activity and increases beta-dystroglycan levels in the diaphragm of the dystrophin-deficientmdxMOUSE. Muscle Nerve 2012; 46:810-3. [DOI: 10.1002/mus.23468] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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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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Chaves-Moreira D, Chaim OM, Sade YB, Paludo KS, Gremski LH, Donatti L, de Moura J, Mangili OC, Gremski W, da Silveira RB, Senff-Ribeiro A, Veiga SS. Identification of a direct hemolytic effect dependent on the catalytic activity induced by phospholipase-D (dermonecrotic toxin) from brown spider venom. J Cell Biochem 2009; 107:655-66. [DOI: 10.1002/jcb.22148] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Santos-Filho NA, Silveira LB, Oliveira CZ, Bernardes CP, Menaldo DL, Fuly AL, Arantes EC, Sampaio SV, Mamede CC, Beletti ME, de Oliveira F, Soares AM. A new acidic myotoxic, anti-platelet and prostaglandin I2 inductor phospholipase A2 isolated from Bothrops moojeni snake venom. Toxicon 2008; 52:908-17. [DOI: 10.1016/j.toxicon.2008.08.020] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2008] [Revised: 08/07/2008] [Accepted: 08/08/2008] [Indexed: 10/21/2022]
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Abstract
Phospholipase A(2) (PLA(2)), a common toxic component of snake venom, has been implicated in various pharmacological effects. Ecarpholin S, isolated from the venom of the snake Echis carinatus sochureki, is a phospholipase A(2) (PLA(2)) belonging to the Ser(49)-PLA(2) subgroup. It has been characterized as having low enzymatic but potent myotoxic activities. The crystal structures of native ecarpholin S and its complexes with lauric acid, and its inhibitor suramin, were elucidated. This is the first report of the structure of a member of the Ser(49)-PLA(2) subgroup. We also examined interactions of ecarpholin S with phosphatidylglycerol and lauric acid, using surface plasmon resonance, and of suramin with isothermal titration calorimetry. Most Ca(2+)-dependent PLA(2) enzymes have Asp in position 49, which plays a crucial role in Ca(2+) binding. The three-dimensional structure of ecarpholin S reveals a unique conformation of the Ca(2+)-binding loop that is not favorable for Ca(2+) coordination. Furthermore, the endogenously bound fatty acid (lauric acid) in the hydrophobic channel may also interrupt the catalytic cycle. These two observations may account for the low enzymatic activity of ecarpholin S, despite full retention of the catalytic machinery. These observations may also be applicable to other non-Asp(49)-PLA(2) enzymes. The interaction of suramin in its complex with ecarpholin S is quite different from that reported for the Lys(49)-PLA(2)/suramin complex(,) where the interfacial recognition face (i-face), C-terminal region, and N-terminal region of ecarpholin S play important roles. This study provides significant structural and functional insights into the myotoxic activity of ecarpholin S and, in general, of non-Asp(49)-PLA(2) enzymes.
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Cintra-Francischinelli M, Silva MG, Andréo-Filho N, Gerenutti M, Cintra ACO, Giglio JR, Leite GB, Cruz-Höfling MA, Rodrigues-Simioni L, Oshima-Franco Y. Antibothropic action ofCasearia sylvestris Sw. (Flacourtiaceae) extracts. Phytother Res 2008; 22:784-90. [DOI: 10.1002/ptr.2365] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Son EW, Lee SR, Choi HS, Koo HJ, Huh JE, Kim MH, Pyo S. Effects of supplementation with higher levels of manganese and magnesium on immune function. Arch Pharm Res 2007; 30:743-9. [PMID: 17679553 DOI: 10.1007/bf02977637] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The magnesium (Mg) and manganese (Mn) were evaluated for its effectiveness as an immunomodulator in rats. The treatments were as follows: Group 1, AIN-93M diet (0.05% Mg, 0.001% Mn); Group 2, high-dose Mg (0.1% Mg, 0.001% Mn); and Group 3, high dose Mn (0.05% Mg, 0.01% Mn) (n-12/group). After 12 weeks of supplementation, rats were sacrificed to assess the effect on a range of innate responses (tumoricidal activity, oxidative burst and nitric oxide) and the mitogen-stimulated lymphoproliferative response. Immune function was significantly affected in both the high dose Mg and the Mn group. Lymphocyte proliferative responses and NK cell activity were measured in pooled spleen from each group. The mitogen response of lymphocytes to LPS in the spleen was significantly reduced in high dose Mg-treated groups, whereas the response to ConA was not affected in both high dose minerals-treated groups. The reactive oxygen species level of macrophages was decreased in both groups. These effects were more pronounced in high dose Mg-treated group. Nitric oxide production was also decreased in high dose minerals-treated group. In addition, tumoricidal activities of splenic NK cell and peritoneal macrophage in mineral exposed rats were significantly increased. Moreover, percent death of macrophage was reduced in two groups receiving high dose mineral supplements. Taken together, the present data suggest that high dose trace min erals exert a differential effect on the function of immune cells.
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Affiliation(s)
- Eun-Wha Son
- Department of Pharmacognosy and Material Development, Kangwon National University, Samcheok 245-711, Korea
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11
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Rodrigues RS, Izidoro LFM, Teixeira SS, Silveira LB, Hamaguchi A, Homsi-Brandeburgo MI, Selistre-de-Araújo HS, Giglio JR, Fuly AL, Soares AM, Rodrigues VM. Isolation and functional characterization of a new myotoxic acidic phospholipase A2 from Bothrops pauloensis snake venom. Toxicon 2007; 50:153-65. [PMID: 17451767 DOI: 10.1016/j.toxicon.2007.03.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2006] [Revised: 03/06/2007] [Accepted: 03/07/2007] [Indexed: 11/16/2022]
Abstract
This article reports the purification procedure and the biochemical/functional characterization of Bp-PLA(2), a new myotoxic acidic phospholipase A(2) from Bothrops pauloensis snake venom. It was highly purified through three chromatographic steps (ion-exchange on CM-Sepharose, hydrophobic chromatography on Phenyl-Sepharose and RP-HPLC on a C8 column). Bp-PLA(2) is a single-chain protein of 15.8kDa and pI 4.3. Its N-terminal sequence revealed a high homology with other Asp49 acidic PLA(2)s from snake venoms. Its specific activity was 585.3U/mg. It displayed a high indirect hemolytic activity and inhibited platelet aggregation induced by collagen or ADP. It also induced in vivo edema and myotoxicity. Pretreatment of Bp-PLA(2) with BPB reduced the enzymatic activity, the inhibitory action on platelet aggregation and myotoxicity in vitro. Morphological analyses indicated that Bp-PLA(2) induced an intense edema, with visible leukocyte infiltrate and damaged muscle cells 24h after injection. Acidic myotoxic PLA(2)s from Bothrops snake venoms are still not extensively explored and knowledge of their structural and functional features will contribute for a better understanding of their action mechanism regarding enzymatic and toxic activities.
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Affiliation(s)
- Renata S Rodrigues
- Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
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Ponce-Soto LA, Bonfim VL, Rodrigues-Simioni L, Novello JC, Marangoni S. Determination of Primary Structure of Two Isoforms 6-1 and 6-2 PLA2 D49 from Bothrops jararacussu Snake Venom and Neurotoxic Characterization Using in vitro Neuromuscular Preparation. Protein J 2006; 25:147-55. [PMID: 16862457 DOI: 10.1007/s10930-006-0006-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In this paper we reported the purification, the biological characterization and the amino acid sequence of two new isoforms basic 6-1 (Bj-IV) and 6-2 (Bj-V) PLA(2) D49 purified from the Bothrops jararacussu venom. The isoforms 6-1 and 6-2 had a sequence of amino acids of 121 amino acid residues 6-1: DLFEWGQMIL KETGKNPFPY YGAYGCYCGW GGRGKPKDKD TDRCCYVHDC CYKKLTGCPK TDDRYSYSWL DLTIVCGEDD PCKELCECDK AIAVCFRENL GTYNKKYRYH LKPCKKADKP C and pI value 7.83 and 6-2: DLWQFGQMIL KETGKIPFPY YGAYGCYCGW GGRGGKPKDG TDRCCYVHDC CYKKLTGCPK TDDRYSYSWL DLTIVCGEDD PCKELCECDK AIAVCFRENL GTYNKKYRYH LKPCKKADKP C with a pI value of 7.99. Skeletal muscle preparations from the young chicken have been used previously in order to study the effects of toxins on neuromuscular transmission, providing an important opportunity to study the differentiated behavior of a toxin before more than one model, because it shows differences in its sensibilities. Both isoforms have produced neuromuscular blockade in young chicken biventer cervicis nerve-muscle preparations in presence or absence of crotapotin crotalic (F3 and F4) indicating that catalytic activity was not essential for neuromuscular action in this preparation.
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Affiliation(s)
- L A Ponce-Soto
- Department of Biochemistry, Institute of Biology, State University of Campinas, SP, Brazil.
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Kashima S, Roberto PG, Soares AM, Astolfi-Filho S, Pereira JO, Giuliati S, Faria M, Xavier MAS, Fontes MRM, Giglio JR, França SC. Analysis of Bothrops jararacussu venomous gland transcriptome focusing on structural and functional aspects: I--gene expression profile of highly expressed phospholipases A2. Biochimie 2005; 86:211-9. [PMID: 15134836 DOI: 10.1016/j.biochi.2004.02.002] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2003] [Accepted: 02/09/2004] [Indexed: 11/26/2022]
Abstract
Snake venom glands are a rich source of bioactive molecules such as peptides, proteins and enzymes that show important pharmacological activity leading to in local and systemic effects as pain, edema, bleeding and muscle necrosis. Most studies on pharmacologically active peptides and proteins from snake venoms have been concerned with isolation and structure elucidation through methods of classical biochemistry. As an attempt to examine the transcripts expressed in the venom gland of Bothrops jararacussu and to unveil the toxicological and pharmacological potential of its products at the molecular level, we generated 549 expressed sequence tags (ESTs) from a directional cDNA library. Sequences obtained from single-pass sequencing of randomly selected cDNA clones could be identified by similarities searches on existing databases, resulting in 197 sequences with significant similarity to phospholipase A(2) (PLA(2)), of which 83.2% were Lys49-PLA(2) homologs (BOJU-I), 0.1% were basic Asp49-PLA(2)s (BOJU-II) and 0.6% were acidic Asp49-PLA(2)s (BOJU-III). Adjoining this very abundant class of proteins we found 88 transcripts codifying for putative sequences of metalloproteases, which after clustering and assembling resulted in three full-length sequences: BOJUMET-I, BOJUMET-II and BOJUMET-III; as well as 25 transcripts related to C-type lectin like protein including a full-length cDNA of a putative galactose binding C-type lectin and a cluster of eight serine-proteases transcripts including a full-length cDNA of a putative serine protease. Among the full-length sequenced clones we identified a nerve growth factor (Bj-NGF) with 92% identity with a human NGF (NGHUBM) and an acidic phospholipase A(2) (BthA-I-PLA(2)) displaying 85-93% identity with other snake venom toxins. Genetic distance among PLA(2)s from Bothrops species were evaluated by phylogenetic analysis. Furthermore, analysis of full-length putative Lys49-PLA(2) through molecular modeling showed conserved structural domains, allowing the characterization of those proteins as group II PLA(2)s. The constructed cDNA library provides molecular clones harboring sequences that can be used to probe directly the genetic material from gland venom of other snake species. Expression of complete cDNAs or their modified derivatives will be useful for elucidation of the structure-function relationships of these toxins and peptides of biotechnological interest.
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Affiliation(s)
- Simone Kashima
- Unidade de Biotecnologia, Universidade de Ribeirão Preto, UNAERP, 14096-380 Ribeirao Preto, SP, Brazil
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Kuruppu S, Isbister GK, Hodgson WC. Phospholipase A2-dependent effects of the venom from the new guinean small-eyed snakeMicropechis ikaheka. Muscle Nerve 2005; 32:81-7. [PMID: 15803483 DOI: 10.1002/mus.20334] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The New Guinean small-eyed snake (Micropechis ikaheka) is a cause of life-threatening envenoming. Previous studies on M. ikaheka venom have indicated the presence of neurotoxins as well as myotoxins. This study examined the in vitro myotoxic effects of M. ikaheka venom and the efficacy of a polyvalent antivenom in neutralizing these effects. Venom (50 microg/ml) produced a slowly developing contracture and inhibition of direct twitches of the chick biventer cervicis nerve-muscle preparation in the presence of tubocurarine (10 microM). Myotoxicity was confirmed by subsequent histological examination of tissues. This myotoxicity was prevented by the prior addition of polyvalent snake antivenom (30 U/ml). However, the addition of antivenom (30 U/ml) 1 h after venom administration failed to reverse or prevent the further inhibition of direct twitches. In addition, venom (1-10 microg/ml) produced concentration-dependent contractions of the guinea-pig isolated ileum. These effects were dependent on phospholipase A2 (PLA2) activity of the venom as evidenced by the ability of the PLA2 inhibitor 4-bromophenacyl bromide (4-BPB; 1.8 mM) to prevent this activity. This study indicates that M. ikaheka venom causes significant myotoxicity and that polyvalent snake antivenom may be a potential treatment for the myotoxic effects in patients envenomed by this species.
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Affiliation(s)
- Sanjaya Kuruppu
- Monash Venom Group, Department of Pharmacology, Building 13E, Monash University, Victoria 3800, Australia
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Oshima-Franco Y, Leite GB, Belo CAD, Hyslop S, Prado-Franceschi J, Cintra ACO, Giglio JR, da Cruz-Höfling MA, Rodrigues-Simioni L. The Presynaptic Activity of Bothropstoxin-I, a Myotoxin from Bothrops jararacussu Snake Venom. ACTA ACUST UNITED AC 2004; 95:175-82. [PMID: 15504153 DOI: 10.1111/j.1742-7843.2004.pto_950405.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Bothropstoxin-I from Bothrops jararacussu snake venom is a lysine-49 phospholipase A(2) with myotoxic and neurotoxic activities. In this study, we used mouse phrenic nerve-diaphragm preparations in the absence and presence of manganese (Mn(2+)), a presynaptic blocker, to investigate a possible presynaptic action of bothropstoxin-I. At concentrations of 0.9 mM and 1.8 mM, Mn(2+) produced 50% neuromuscular blockade in less than 4 min., which was spontaneously reversible at the lower concentration. Bothropstoxin-I (1.4 microM) irreversibly inhibited neuromuscular blockade by 50% in 31+/-4 min. (mean+/-S.E.M., n = 9). Pretreating preparations with 0.9 mM Mn(2+) prevented the blockade by bothropstoxin-I. When added after bothropstoxin-I, Mn(2+) produced its characteristic blockade and, after washing, the twitch tension returned to pre-Mn(2+) levels, indicating that bothropstoxin-I caused irreversible damage before the addition of Mn(2+). Electrophysiological measurements showed that a concentration of bothropstoxin-I (0.35 microM), which did not produce neuromuscular blockade, caused the appearance of giant miniature end-plate potentials with no change in the membrane resting potential but increased the quantal content. Preparations preincubated with Mn(2+) (0.9 mM, 30 min.) were protected against the depolarizing action of bothropstoxin-I (0.7 microM). These results show that, in addition to its well-known myotoxic effect, bothropstoxin-I also has a presynaptic action.
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Affiliation(s)
- Yoko Oshima-Franco
- Department of Pharmacology, Faculty of Medical Sciences, Institute of Biology, State Univeristy of Campinas (UNICAMP), 13083-970, Campinas, SP, Brazil
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Rodrigues VM, Marcussi S, Cambraia RS, de Araújo AL, Malta-Neto NR, Hamaguchi A, Ferro EAV, Homsi-Brandeburgo MI, Giglio JR, Soares AM. Bactericidal and neurotoxic activities of two myotoxic phospholipases A2 from Bothrops neuwiedi pauloensis snake venom. Toxicon 2004; 44:305-14. [PMID: 15302537 DOI: 10.1016/j.toxicon.2004.06.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2003] [Revised: 06/07/2004] [Accepted: 06/09/2004] [Indexed: 10/26/2022]
Abstract
Two basic myotoxic PLA(2)s, namely BnpTX-I and II, were isolated from Bothrops neuwiedi pauloensis snake venom through three chromatographic steps: ion-exchange chromatography on CM-Sepharose, gel filtration on Sephadex G-50 and reverse phase HPLC on a C18 column. Both PLA(2)s showed a M(r) around 14,000 for the monomer and 28,000 for the dimer (as estimated by SDS-PAGE), pI approximately 7.8 and approximately 121 amino acid residues cross-linked by seven disulfide bonds. The N-terminal sequences revealed significant homology with Asp49 basic myotoxic PLA(2)s from other snake venoms. The catalytic and anticoagulant activities of BnpTX-I were higher than those of BnpTX-II. Both were able to induce cytotoxicity in vitro, as well as, myotoxicity, edema and lethality in mice. BnpTX-I also induced neurotoxic effect on mouse neuromuscular preparations and bactericidal activity on Eschericia coli and Staphylococcus aureus. After chemical modification of BnpTX-I with BPB or incubation with EDTA or Mn(2+) ions, the catalytic activity was completely abolished, while the toxic and pharmacological activities were partially reduced. Interaction with heparin inhibited the cytotoxic and bactericidal effects. Anti-BthTX-I, anti-BthTX-II and anti-115-129-C terminal antibodies strongly recognize both BnpTX-I and II. It is shown that the neurotoxic effect induced by B. neuwiedi pauloensis venom is due to the presence of myotoxic PLA(2)s. The data also corroborate the hypothesis of a partial dissociation between toxic and enzymatic domains. In addition, BnpTX-I displays a heparin binding C-terminal region, which is probably responsible for the cytotoxic and bactericidal effects.
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Affiliation(s)
- Veridiana M Rodrigues
- Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, UFU, Uberlândia, MG, Brazil
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Zamunér SR, da Cruz-Höfling MA, Corrado AP, Hyslop S, Rodrigues-Simioni L. Comparison of the neurotoxic and myotoxic effects of Brazilian Bothrops venoms and their neutralization by commercial antivenom. Toxicon 2004; 44:259-71. [PMID: 15302532 DOI: 10.1016/j.toxicon.2004.05.029] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2002] [Accepted: 05/13/2004] [Indexed: 10/26/2022]
Abstract
The venoms of some Bothrops species produce neuromuscular blockade in avian and mammalian nerve-muscle preparations in vitro. In this study, we compared the neuromuscular activities (myotoxicity and neurotoxicity) of venoms from several Brazilian species of Bothrops (B. jararaca, B. jararacussu, B. moojeni, B. erythromelas and B. neuwiedi) in chick isolated biventer cervicis muscle preparations and examined their neutralization by commercial antivenom. All of the venoms (50-200 microg/ml, n = 3 - 7 each) induced long-lasting, concentration-dependent muscle contracture and twitch-tension blockade, and also inhibited the muscle responses to acetylcholine and KCl. Preincubation of the venoms (200 microg/ml) with bothropic antivenom (0.2 ml) for 30 min at 37 degrees C prevented the twitch-tension blockade to different extents, with the protection varying from 0.5% (B. neuwiedi) to 88% (B. moojeni). Complete protection against the neuromuscular action of B. neuwiedi venom was observed only with a mixture of bothropic and crotalic antivenoms. The venoms caused either high (B. jararacussu, B. neuwiedi and B. moojeni) or low (B. jararaca and B. erythromelas) creatine kinase release. Morphologically, myonecrosis was greatest with B. jararacussu venom (98-100% of fibers damaged) and least with B. jararaca venom (74% damage). The extent of neutralization by bothropic antivenom was B. jararaca (93%)>B. erythromelas (65.8%)>B. moojeni (30.7%)>B. neuwiedi (20%)>B. jararacussu (no neutralization). Despite this variation in neutralization, enzyme-linked immunosorbent assays indicated similar immunoreactivities for the venoms, although immunoblots revealed quantitative variations in the bands detected. These results show that Bothrops venoms produce varying degrees of neuromuscular blockade in chick nerve-muscle preparations. The variable protection by antivenom against neuromuscular activity indicates that the components responsible for the neuromuscular action may differ among the venoms.
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Affiliation(s)
- Stella R Zamunér
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas, P.O. Box 6111, 13083-970, Campinas, SP, 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: 223] [Impact Index Per Article: 10.6] [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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Wickramaratna JC, Fry BG, Aguilar MI, Kini RM, Hodgson WC. Isolation and pharmacological characterization of a phospholipase A2 myotoxin from the venom of the Irian Jayan death adder (Acanthophis rugosus). Br J Pharmacol 2003; 138:333-42. [PMID: 12540524 PMCID: PMC1573671 DOI: 10.1038/sj.bjp.0705046] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. It has long been thought that death adder venoms are devoid of myotoxic activity based on studies done on Acanthophis antarcticus (Common death adder) venom. However, a recent clinical study reported rhabdomyolysis in patients following death adder envenomations, in Papua New Guinea, by a species thought to be different to A. antarcticus. Consequently, the present study examined A. rugosus (Irian Jayan death adder) venom for myotoxicity, and isolated the first myotoxin (acanmyotoxin-1) from a death adder venom. 2. A. rugosus (10-50 micro g ml(-1)) and acanmyotoxin-1 (MW 13811; 0.1-1 micro M) were screened for myotoxicity using the chick directly (0.1 Hz, 2 ms, supramaximal V) stimulated biventer cervicis nerve-muscle (CBCNM) preparation. A significant contracture of skeletal muscle and/or inhibition of direct twitches were considered signs of myotoxicity. This was confirmed by histological examination. 3. High phospholipase A(2) (PLA(2)) activity was detected in both A. rugosus venom (140.2+/-10.4 micro mol min(-1) mg(-1); n=6) and acanmyotoxin-1 (153.4+/-11 micro mol min(-1) mg(-1); n=6). Both A. rugosus venom (10-50 micro g ml(-1)) and acanmyotoxin-1 (0.1-1 micro M) caused dose-dependent inhibition of direct twitches and increase in baseline tension (n=4-6). In addition, dose-dependent morphological changes in skeletal muscle were observed. 4. Prior incubation (10 min) of CSL death adder antivenom (5 units ml(-1); n=4) or inactivation of PLA(2) activity with 4-bromophenacyl bromide (1.8 mM; n=4) prevented the myotoxicity caused by acanmyotoxin-1 (1 micro M). 5. Acanmyotoxin-1 (0.1 micro M; n=4) displayed no significant neurotoxicity when it was examined using the indirectly (0.1 Hz, 0.2 ms, supramaximal V) stimulated CBCNM preparation. 6. In conclusion, clinicians may need to be mindful of possible myotoxicity following death adder envenomation in Irian Jaya.
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Affiliation(s)
- Janith C Wickramaratna
- Monash Venom Group, Department of Pharmacology, P.O. Box 13E, Monash University, Victoria 3800, Australia
| | - Bryan G Fry
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore 119260
- Australian Venom Research Unit, Department of Pharmacology, University of Melbourne, Victoria 3010, Australia
| | - Marie-Isabel Aguilar
- Department of Biochemistry and Molecular Biology, P.O. Box 13D, Monash University, Victoria 3800, Australia
| | - R Manjunatha Kini
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore 119260
| | - Wayne C Hodgson
- Monash Venom Group, Department of Pharmacology, P.O. Box 13E, Monash University, Victoria 3800, Australia
- Author for correspondence:
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