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Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1040378


Background Snakebite treatment requires administration of an appropriate antivenom that should contain antibodies capable of neutralizing the venom. To achieve this goal, antivenom production must start from a suitable immunization protocol and proper venom mixtures. In Brazil, antivenom against South American rattlesnake (Crotalus durissus terrificus) bites is produced by public institutions based on the guidelines defined by the regulatory agency of the Brazilian Ministry of Health, ANVISA. However, each institution uses its own mixture of rattlesnake venom antigens. Previous works have shown that crotamine, a toxin found in Crolatus durissus venom, shows marked individual and populational variation. In addition, serum produced from crotamine-negative venoms fails to recognize this molecule. Methods In this work, we used an antivenomics approach to assess the cross-reactivity of crotalic antivenom manufactured by IVB towards crotamine-negative venom and a mixture of crotamine-negative/crotamine-positive venoms. Results We show that the venom mixture containing 20% crotamine and 57% crotoxin produced a strong immunogenic response in horses. Antivenom raised against this venom mixture reacted with most venom components including crotamine and crotoxin, in contrast to the antivenom raised against crotamine-negative venom. Conclusions These results indicate that venomic databases and antivenomics analysis provide a useful approach for choosing the better venom mixture for antibody production and for the subsequent screening of antivenom cross-reactivity with relevant snake venom components.(AU)

Mordeduras e Picadas , Antivenenos , Crotalus cascavella , Venenos de Crotalídeos , Formação de Anticorpos
CuidArte, Enferm ; 9(2)jul.-dez.2015.
Artigo em Português | BDENF - Enfermagem, BDENF - Enfermagem | ID: biblio-1027919


Introdução: O uso de animais em pesquisa científica vem sendo ponto de discussão na última década, baseado na teoria dos 3Rs - Reduction, Refinement and Replacement. Objetivo: Avaliar o uso da pele de cobra brasileira (Crotalus durissus terrificus) como membrana biológica para ensaios in vitro de permeação cutânea, usando nicotina em adesivos transdérmicos como medicamento modelo. Há muitas similaridades nas taxas de permeação entre o estrato córneo humano e a pele de cobra, a qual sugere o uso da pele de cobra como um modelo de barreira nos ensaios de permeação através do estrato córneo. A pele de cobra pode vir a ser um substituto em potencial para o uso de animais de laboratórios, reduzindo o número de animais utilizados nas pesquisas, a dor e desconforto dos animais durante os experimentos. É importante procurar alternativas para substituição dos animais tanto em ensaios laboratoriais in vitro como nos ensaios in vivo. Material e Método: Experimento de laboratório. Ensaio in vitro de permeação cutânea utilizando pele de cobra pré-hidratada em água durante 12, 24 e 48 horas...

Introduction: Based on the theory of the 3Rs - Reduction, Refinement and Replacement, the use of animals in scientific research has been focused in the past decade. Objective: To assess the use of Brazilian snake (Crotalus durissus terrificus) skin as a biological membrane for in vitro skin permeation studies using nicotine transdermal patches as a drug model. There are many similarities in the permeation rates between the snake skin and the human stratum corneum, which suggest the use of this tissue as a barrier model to test drug permeation through the stratum corneum. The use of snake skin may become a potential replacement for the use of laboratory animals, reducing this way the number of animals used in research, as well as the pain and discomfort of animals during the experiments. It is important to seek alternatives in order to replace these animals both in vitro and in vivo laboratory assays. Materials and Methods: Laboratory Experiment – During in vitro skin permeation studies using pre-treated with water hydration for 12, 24 and 48 hours snake skin, nicotine was used as a model drug, as well as a vertical diffusion cell as apparatus. The nicotine values permeated through snake skin were determined by High Performance Liquid Chromatography, being...

Introducción: El uso de animales en la investigación científica está siendo tema de debate en la última década, basado en la teoría de las 3Rs - Reducción, Refinamiento y Reemplazo. Objetivo: Evaluar el uso de la piel de serpiente brasileña (Crotalus durissus terrificus) como membrana biológica para las pruebas in vitro de la permeabilidad cutánea, el uso de la nicotina en parches transdérmicos como modelo de producto medicinal. Existen muchas similitudes entre los índices de permeabilidad en el estrato córneo y la serpiente humana, lo que sugiere el uso como modelo de barrera en las pruebas de la infiltración a través del estrato córneo. La serpiente puede ser un sustituto potencial para el uso de animales de laboratorio, reduciendo el número de animales utilizados en la investigación, el dolor y el sufrimiento de los animales durante los experimentos. Es importante buscar alternativas para animales de reemplazo tanto en pruebas de laboratorio ensayos in vivo e in vitro. Material y Método: Experimento de laboratorio - En ensayos de permeación in vitro utilizando piel de serpiente pre-tratados con hidratación en agua durante 12, 24 y 48 horas, la nicotina fue utilizado como um modelo de droga y célula de difusión vertical como lo aparato. Los valores de nicotina permeada por la piel de serpiente...

Animais , Animais de Laboratório , Crotalus cascavella , Técnicas In Vitro/métodos
J. venom. anim. toxins incl. trop. dis ; 21: 48, 31/03/2015. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954772


Background American visceral leishmaniasis is caused by the intracellular parasiteLeishmania (L.) infantum chagasi, and transmitted by the sand fly Lutzomyia longipalpis. Since treatment is based on classical chemotherapeutics with significant side effects, the search for new drugs remains the greatest global challenge. Thus, this in vitro study aimed to evaluate the leishmanicidal effect ofCrotalus durissus terrificus venom fractions on promastigote and amastigote forms of Leishmania (L.) infantum chagasi. Methods Phospholipase A 2 (PLA 2 ) and a pool of peptide fraction (<3 kDa) were purified from Crotalusvenom. Furthermore, promastigotes and peritoneal macrophages of mice infected by amastigotes were exposed to serial dilutions of the PLA 2 and peptides at intervals varying between 1.5625 μg/mL and 200 μg/mL. Both showed activity against promastigotes that varied according to the tested concentration and the time of incubation (24, 48 and 72 h). Results MTT assay for promastigotes showed IC 50 of 52.07 μg/mL for PLA2 and 16.98 μg/mL for the peptide fraction of the venom. The cytotoxicity assessment in peritoneal macrophages showed IC50 of 98 μg/mL and 16.98 μg/mL for PLA 2 and peptide by MTT assay, respectively. In peritoneal macrophages infected by Leishmania (L.) infantum chagasi amastigotes, the PLA 2 stimulated growth of parasites, and at higher doses reduced growth by 23 %. The peptide fraction prevented 43 % of the intracellular parasite growth at a dose of 16.98 μg/mL, demonstrating the toxicity of this dose to macrophages. Both fractions stimulated H 2 O 2 production by macrophages but only PLA 2 was able to stimulate NO production. Conclusion We have demonstrated the in vitro leishmanicidal activity of the PLA2 and peptide fraction ofCrotalus venom. The results encourage further studies to describe the metabolic pathways involved in cell death, as well as the prospecting of molecules with antiparasitic activity present in the peptide fraction of Crotalus durissus terrificus venom.(AU)

Animais , Peptídeos , Fosfolipases , Técnicas In Vitro , Crotalus cascavella/toxicidade , Leishmania , Redes e Vias Metabólicas
J. venom. anim. toxins incl. trop. dis ; 21: 14, 31/03/2015. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954753


Background:Since ionizing radiation has the potential to alter the molecular structure and affect the biologica properties of biomolecules, it has been successfully employed to attenuate animal toxins. The present study aimed to characterize the structural modifications on irradiated crotamine, a toxin from Crotalus durissus terrificus venom, using circular dichroism (CD), fluorescence, Fourier transformed infrared spectroscopy (FTIR), atomic force microscopy (AFM) and differential scanning calorimetry (DSC).Methods:A combination of size exclusion and ion-exchange chromatography was used to purify the peptide using crude venom. The pure toxin was then submitted to 2 kGy gamma irradiation doses from a cobalt-60 source. Native and irradiated crotamine were analyzed using a fluorescence spectrophotometer. Wavelength was fixed at 295 nm and fluorescence emission scans were collected from 300 to 400 nm. CD and FTIR techniques were used to identify the secondary structure of both samples. DSC analyses were performed at a starting temperature of 20 °C up to a final temperature of 90 °C. AFM provided a 3D profile of the surfaces of both crotamine forms adsorbed on mica.Results:Fluorescence spectroscopy showed that the quantum yield of the irradiated form decreased. CD spectra of native and irradiated crotamine solutions showed differences between the samples in wavelength, indicating that irradiation induced a transition of a small portion of the random coil regions towards an a-helical conformation. FTIR and CD showed that the native and irradiated crotamine spectra were different with regard to secondary structure. The thermodynamic analysis showed that irradiation caused changes in the calorimetric profile and CD showed that temperature-induced changes also occur in the secondary structure. Finally, AFM showed the possible formation of insoluble aggregates.Conclusions:Our results indicate that irradiation leads to progressive changes in the structure of the toxin, which could explain a decrease in myotoxic activity.(AU)

Animais , Radiação Ionizante , Varredura Diferencial de Calorimetria , Crotalus cascavella , Dicroísmo Circular , Microscopia de Força Atômica
Pesqui. vet. bras ; 34(4): 301-312, abr. 2014. tab
Artigo em Português | LILACS | ID: lil-712716


Foi realizada uma revisão dos quadros clínico-patológicos causados pelos venenos de Crotalus durissus terrificus e Bothrops spp. em bovinos, búfalos, ovinos equinos e suínos. Foram compilados os dados obtidos pela experimentação em animais de produção encontrados na literatura e os obtidos através de experimentação realizada por nossa equipe. Também foram revisados os casos naturais de envenenamento ofídico comunicados. Em dois Quadros foram lançados os mais importantes dados dessas revisões, que revelou diversos aspectos interessantes: 1) em nossos experimentos, o veneno de Crotalus durissus terrificus, quando injetado por via subcutânea em cavalos, causou um edema acentuado no local da aplicação, ao contrário do que tem sido observado em todas as outras espécies animais, aspecto não relatado na literatura; 2) em nossos experimentos, o veneno de diversas espécies de Bothrops, quando injetado por via subcutânea em bovinos, ovinos e equinos, não causou edema como em geral é relatado na literatura, e sim hemorragias subcutâneas acentuadas no local da aplicação. Nos casos não fatais este sangue era reabsorvido em poucos dias sem deixar sequelas. Exceção foi a reação ao veneno de Bothrops jararacussu, que causou edema nos ovinos experimentais, e tumefação acentuada que resultou em fístula com eliminação de líquido seroso nos equinos experimentais. O objetivo do presente estudo visa contribuir para o aperfeiçoamento do diagnóstico de acidentes ofídicos em animais de produção.

A review was performed about the clinical and pathological pictures caused by the venoms of Crotalus durissus terrificus and Bothrops spp. in cattle, buffaloes, horses, sheep and swine. The data were compiled from experiments in livestock species found in the literature, from experimentation accomplished by our research group, and from communicated natural cases of snakebite poisoning. The most important data were placed on two Tables, the analysis of which revealed some interesting aspects: (1) in our experiments the venom of Crotalus durissus terrificus caused in horses severe edema at the site of subcutaneous injection, to the contrary as observed in all other experimental animal species, an aspect not recorded in the literature; (2) in our experiments the venom of Bothrops species in cattle, sheep and horses, injected subcutaneously, did not cause edema as generally reported in the literature, but caused severe subcutaneous hemorrhages at the injection site. In the non fatal cases the blood was reabsorbed in a few days without leaving sequelae; exception was the reaction to the venom of Bothrops jararacussu, which caused edema in the experimental sheep, and severe tumefaction resulting in fistulous elimination of serous liquid in the experimental horses. The aim of this study was to contribute for the diagnostic of snakebite accidents in livestock.

Animais , Animais Domésticos , Bothrops , Crotalus cascavella/envenenamento , Venenos de Serpentes/administração & dosagem , Mordeduras de Serpentes/diagnóstico , Mordeduras de Serpentes/veterinária
Experimental Biology and Medicine ; 237(10): 1219-1230, Oct 8, 2012.
Artigo em Inglês | Sec. Est. Saúde SP, Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1062786


Crotalus durissus terrificus snake venom (CdtV) has long-lasting anti-inflammatory properties and inhibits the spreading andphagocytic activity of macrophages. Crotoxin (CTX), the main component of CdtV, is responsible for these effects.Considering the role of neutrophils in the inflammatory response and the lack of information about the effect of CdtV onneutrophils, the aim of this study was to investigate the effect of CdtV and CTX on two functions of neutrophils, namelyphagocytosis and production of reactive oxygen species, and on the intracellular signaling involved in phagocytosis,particularly on tyrosine phosphorylation and rearrangements of the actin cytoskeleton. Our results showed that theincubation of neutrophils with CdtV or CTX, at different concentrations, or the subcutaneous injection of CdtV or CTX inrats two hours or one, four or 14 days before or one hour after the induction of inflammation inhibited the phagocyticactivity of neutrophils. Furthermore, these in vitro and in vivo effects were associated with CdtV and CTX inhibition oftyrosine phosphorylation and consequently actin polymerization. Despite the inhibitory effect on phagocytosis, this study demonstrated that CdtV and CTX did not alter the production of the main reactive oxygen species. Therefore, this studycharacterized, for the first time, the actions of CdtV on neutrophils and demonstrated that CTX induces a long-lasting inhibition of tyrosine phosphorylation and consequently phagocytosis. We suggest that CTX represents a potential naturalproduct in controlling inflammatory diseases, since a single dose exerts a long-lasting effect on intracellular signaling involved in phagocytosis by neutrophils.

Animais , Antivenenos , Crotalus cascavella , Crotoxina/antagonistas & inibidores , Venenos de Serpentes
Pesqui. vet. bras ; 32(9): 843-849, set. 2012. ilus, tab
Artigo em Português | LILACS | ID: lil-654362


Descrevem-se os quadros clínico-patológicos e laboratoriais de equinos inoculados experimentalmente com a peçonha de Caudisona durissa terrificus (Crotalus durissus terrificus na antiga nomenclatura), com a finalidade de fornecer subsídios que favoreçam a compreensão desse tipo de acidente ofídico em equinos. O veneno liofilizado foi diluído em 1ml de solução salina a 0,9% e inoculado por via subcutânea em cinco equinos, nas doses de 0,12mg/kg (um animal), 0,066mg/kg (dois animais) e 0,03mg/kg (dois animais). O veneno causou a morte do equino que recebeu a dose de 0,12mg/kg e de um dos dois que receberam a dose de 0,066mg/kg, com evolução de 27h27min e 52h29min, respectivamente. O segundo animal que recebeu a dose de 0,066mg/kg também adoeceu, mas recuperou-se após 12 dias da inoculação. A dose de 0,03mg/kg determinou quadros não fatais do envenenamento, com período de evolução que variou entre 6 e 10 dias. O quadro clínico caracterizou-se por considerável aumento de volume no local de inoculação (escápula) que se estendeu por todo o membro, apatia e cabeça baixa, alterações locomotoras evidenciadas pelo arrastar das pinças no solo, decúbito e dificuldade para levantar, redução dos reflexos auricular, palatal, do lábio superior e de ameaça, e aumento das frequências cardíaca e respiratória. Os exames laboratoriais revelaram leucocitose por neutrofilia e linfocitose em apenas dois animais. Houve aumento das enzimas creatina quinase (CK), dehidrogenase láctica (DHL) e da ureia, e também redução nos níveis séricos de cálcio, fósforo e magnésio. O tempo de tromboplastina parcial ativada (TTPA) aumentou nos equinos que morreram. Os achados de necropsia foram edema do tecido subcutâneo em todo o membro em que foi aplicado o veneno, sufusões no epicárdio dos ventrículos cardíacos esquerdo e direito, e bexiga com áreas hemorrágicas em grande parte da mucosa. Ao exame histopatológico observaram-se fígado com moderada vacuolização difusa, afetando mais a zona intermediária do lóbulo hepático, leve dilatação dos sinusoides hepáticos em algumas áreas e rim com leve dilatação dos túbulos uriníferos, principalmente no córtex.

The clinic-pathological picture and laboratory findings in horses experimentally inoculated with the venom of Caudisona durissa terrificus (Crotalus durissus terrificus, according to the former nomenclature) are described. The purpose of this study was to contribute to the understanding of this type of snake accident in horses. The lyophilized venom was diluted into 1ml of a 0.9% saline solution and was inoculated subcutaneously into five horses, at the doses of 0.12mg/kg (one horse), 0.066mg/kg (two horses) and 0.03mg/kg (two horses). The venom caused death of the horse that had received 0.12mg/kg, and of one horse of the two that had received the dose of 0.066mg/kg. The clinical course varied from 27h27min to 52h29min. The second horse inoculated with 0.066mg/kg recovered within 12 days after inoculation. The dose of 0.03mg/kg had a course of 6 to 10 days, but did not cause fatal envenomation. The clinical picture in the horses was characterized by swelling of the inoculation site (shoulder) that spread to the whole leg, by apathy and lowered head, locomotory alterations shown by dragging of the hoves on the ground, decubitus and difficulty to get up, reduction of auricular, palatal, upperlip and threat reflexes, and increase of heart and breathing frequency. The laboratory examination revealed leukocytosis and lymphocytosis in two horses. There was increase of the creatine-kinase (CK), lactic dehydrogenase (DHL) and urea, and reduction in the seric levels of calcium, phosphorus and magnesium. The activated partial tromboplastina time (TTPA) increased in the horses that died. Postmortem findings were edema of the subcutaneous tissue of the whole leg into which the venom was inoculated, suffusions in the epicard of left and right heart ventricles, and bladder with hemorrhagic areas in its mucosa. Histopatologic examination revealed the liver parenchyma with diffuse moderate vacuolation affecting predominantly the intermediate area of the hepatic lobe, and slight dilation of the sinusoides in some areas, and slight dilation of the kidney tubules mainly in the cortex.

Animais , Cavalos/metabolismo , Crotalus cascavella/toxicidade , Testes Laboratoriais , Sinais e Sintomas/veterinária , Leucocitose/veterinária , Linfocitose/veterinária , Neutrófilos/patologia
Acta bioquím. clín. latinoam ; 46(2): 171-182, jun. 2012. ilus
Artigo em Espanhol | LILACS | ID: lil-657440


En el presente trabajo se examinó la interacción de las amanitinas de Amanita phalloides (Basidiomycetes) con los venenos de las serpientes Bothrops neuwiedi diporus ("yarará pequeña"), B. alternatus ("yarará grande"), Crotalus durissus terrificus ("serpiente de cascabel") y de la abeja mielera Apis mellifera. Se aplicaron las técnicas de Ouchterlony, inmunotransferencia, electroforesis rocket y electroforesis en gel de poliacrilamida a los anti-venenos y anti-toxinas obtenidos por inmunización en caballos y/o en conejos. Los anti­sueros de serpientes y las amanitinas reaccionaron en forma cruzada, así como el veneno de abeja y las amanitinas. Cuando los venenos de Bothrops neuwiedii diporus y Crotalus durissus terrificus se preincubaron con las amanitinas y se analizaron por electroforesis en gel de poliacrilamida-dodecilsulfato de sodio (dodecylsulfate-polyacrylamide gel electrophoresis: SDS-PAGE), algunas bandas de proteínas desaparecieron y otras se redujeron notablemente. Estos resultados revelan por primera vez la interacción y la degradación de las proteínas de los venenos de serpientes por las amanitinas. Por otra parte, la modificación del tiempo de coagulación de la sangre humana, debida a los venenos, se corrigió con los ciclopéptidos de Amanita. Estos resultados también se informan por primera vez en este trabajo. La presencia de polipéptidos tóxicos en los venenos de serpientes y abejas, así como en A. phalloides y la reactividad cruzada demostradas en este trabajo, sugieren la existencia de epítopos comunes a todos ellos. Teniendo en cuenta estas reacciones, el uso de anti-venenos heterólogos parece ser de utilidad en el tratamiento del envenenamiento.

In the present work, the interaction of the amanitins of Amanita phalloides (Basidiomycetes) with the venoms of Bothrops neuwiedi diporus ("small yarará snake"), B. alternatus ("big yarará"), Crotalus durissus terrificus ("rattlesnake"), and honey bee Apis mellifera was examined. Ouchterlony, immunotransfer, rocket-electrophoresis, and polyacrylamide gel electrophoresis techniques were applied to anti-venoms and anti-toxins obtained by immunization in horses and/or in rabbits. Snake antisera and amanitins cross-reacted as well as bee venom and amanitins. When venoms of Bothrops neuwiedii diporus and Crotalus durissus terrificus were preincubated with amanitins and analysed by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE), some protein bands disappeared and others were significantly reduced. These results reveal for the first time the interaction and degradation of proteins in snake venoms by amanitins. Moreover, the modification of the human blood clotting time due to snake venoms was corrected by the Amanita cyclopeptides. These results are also reported for the first time in this work. The occurrence of toxic polypeptides in the snake and bee venoms as well as in A. phalloides, and the cross-reactivity demostrated herein, suggest the occurrence of epitopes common to all of them. Taking into account these reactions,the use of heterologous anti-venoms seems to be of value in envenomation treatment.

No presente trabalho foi examinada a interação das amanitinas de Amanita phalloides (Basidiomy­cetes) com os venenos das serpentes Bothrops neuwiedi diporus ("jararaca-cruzeira"), B. alternatus ("urutu"), Crotalus durissus terrificus ("serpente cascavel") e da abelha-europeia Apis mellifera. Foram aplicadas as técnicas de Ouchterlony, imunotransferência, eletroforese rocket e eletroforese em gel de poliacrilamida aos anti-venenos e anti-toxinas obtidos por imunização em cavalos e/ou em coelhos. Os anti-soros de serpentes e as amanitinas reagiram em forma cruzada, bem como o veneno de abelha e as amanitinas. Quando os venenos de Bothrops neuwiedii diporus e Crotalus durissus terrificus foram incubados previamente com as amanitinas e foram analisados por eletroforese em gel de poliacrilamida-dodecilsulfato de sódio (dodecylsulfate-polyacrylamide gel electrophoresis: SDS-PAGE), algumas faixas de proteínas desapareceram e outras se reduziram notavelmente. Estes resultados revelam por primeira vez a interação e a degradação das proteínas dos venenos de serpentes pelas amanitinas. Por outra parte, a modificação do tempo de coagulação do sangue humano, devido aos venenos, se corrigiu com os ciclopeptídeos de Amanita. Estes resultados também se informam por primeira vez neste trabalho. A presença de polipeptídeos tóxicos nos venenos de serpentes e abelhas, bem como em A. phalloides e a reatividade cruzada demonstradas neste trabalho, sugerem a existência de epítopos comuns a todos eles. Levando em consideração estas reações, o uso de anti-venenos heterólogos parece ser de utilidade no tratamento do envenenamento.

Animais , Agaricus phalloides/toxicidade , Amanitinas/toxicidade , Venenos de Abelha , Venenos de Serpentes/toxicidade , Antivenenos , Apis mellifica , Argentina , Bothrops , Venenos de Crotalídeos , Crotalus cascavella
J. venom. anim. toxins incl. trop. dis ; 17(2): 190-198, 2011. graf, tab
Artigo em Inglês | LILACS | ID: lil-587779


Plathymenia reticulata Benth has an anti-inflammatory effect and is capable of neutralizing the neuromuscular blockade induced by Bothrops jararacussu or Crotalus durissus terrificus venoms, probably by precipitating venom proteins (an effect caused by plant tannins). The present study aimed to evaluate the mutagenic activity of P. reticulata by using the Salmonella mutagenicity assay (Ames test) and the micronucleus test in CHO-K1 cells. P. reticulata extract concentrations of 2.84, 5.68, 11.37, and 19.90 mg/plate were assayed by the Ames test using TA97a, TA98, TA100 and TA102 bacterial strains, with (+S9) and without (-S9) metabolic activation. Concentrations of 5, 1.6 and 0.5 ìg/mL of P. reticulata extract were used for the micronucleus test. P. reticulata extract was mutagenic to TA98 (-S9) and showed signs of mutagenic activity in TA97a and TA102 (both -S9) strains. Micronucleus test CBPI values showed that the endogenous metabolic system increased the number of viable cells when compared to the non-activated samples and the micronucleus frequency increased when the cells were treated in the absence of S9. We concluded that P. reticulata extract may present direct mutagenic properties.

Anti-Inflamatórios , Bothrops , Venenos de Crotalídeos , Crotalus cascavella , Solução Hidroalcoólica , Bloqueadores Neuromusculares , Plantas Medicinais , Testes de Mutagenicidade/métodos
Artigo em Inglês | Sec. Est. Saúde SP, Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1065515


Acute renal failure is one of the most serious complications of envenoming resulting from Crotalus durissus terrificus bites. This study evaluated the relevance of hyperuricemia and oxidative stress and the effects of allopurinol and probenecid in renal dysfunction caused by direct nephrotoxicity of C. d. terrificus venom.

Masculino , Feminino , Humanos , Animais , Crotalus cascavella , Mordeduras de Serpentes/classificação , Mordeduras de Serpentes/complicações , Serpentes/classificação , Insuficiência Renal
Curr. pharm. des ; 17(38): 4351-4361, 2011.
Artigo em Inglês | Sec. Est. Saúde SP, Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: biblio-1062307


Crotamine, a low molecular weight cationic polypeptide from the venom of the South American rattlesnake Crotalus durissus terrificus is a natural cell-penetrating peptide with functional versatility. The presence of nine lysine residues and three disulfide bonds renders crotamine highly compact, stable and positively charged. Topologically, crotamine adopts an ancient â-defensin fold that is found in diverse families of endogenous and venom polypeptides dedicated to host defense. Crotamine is unique among several classes of bioactive peptides because it possesses both cell penetrating and antimicrobial activities and selective biological action toward some cell types at a given cell cycle phase. Because it can rapidly and efficiently translocate into actively proliferating cells, crotamine is being investigated for labeling highly replicating cells and for use as a chemotherapeutic adjuvant. Peptides derived from crotamine, nucleolar targeting peptides (NrTPs), have been designed and are being studied. NrTPs retain some crotamine properties, such as efficient cellular uptake and preferential nuclear localization whereas they improve upon other properties. For example, NrTPs are smaller than crotamine, show higher preferential nucleolar localization, and better facilitate ZIP-code localization of therapeutic proteins.

Humanos , Animais , Crotalus cascavella/toxicidade , Crotalus cascavella/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos/química , Serpentes , Venenos de Crotalídeos/farmacologia , Venenos de Crotalídeos/isolamento & purificação , Venenos de Crotalídeos/química , Venenos de Serpentes , Proteínas de Répteis/química
São Paulo; s.n; 2011. 100 p.
Tese em Português | Sec. Est. Saúde SP, Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1079152


Crotamina e um peptideo de baixo peso molecular composto de 42 residuos de aminoacidos. A presenca de nove residuos de lisina e tres pontes dissulfeto confere a crotamina compatibilidade elevada, estabilidade, carga positiva liquida, apresentando similaridade de estrutural com defensina, um peptideo antimicrobiano do epitelio humano...

Crotamine is a low molecular weight peptide composed of 42 amino acid residues. The presence of nine lysine residues and three disulfide bonds confers to crotamine high compactness, stability, net positive charge and overall structural similarity to B- defensin 2, an antimicrobial peptide from the human epithelia...

Animais , Aminoácidos/análise , Aminoácidos/uso terapêutico , Crotalus cascavella/análise , Crotalus cascavella/envenenamento , Melanoma/terapia , Venenos de Crotalídeos/análise , Venenos de Crotalídeos/envenenamento , Venenos de Crotalídeos/farmacocinética , Venenos de Crotalídeos/toxicidade , Peptídeos/administração & dosagem , Peptídeos/análise , Peptídeos/toxicidade , Peptídeos/uso terapêutico
Toxicon ; 55(6): 1045-1060, Jan 28, 2010.
Artigo em Inglês | Sec. Est. Saúde SP, Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1068250


Crotoxin, the main toxin of South American rattlesnake (Crotalus durissus terrificus) venom, was the first snake venom protein to be purified and crystallized. Crotoxin is a heterodimericb-neurotoxin that consists of a weakly toxic basic phospholipase A2 and a nonenzymatic, non-toxic acidic component (crotapotin). The classic biological activities normally attributed to crotoxin include neurotoxicity, myotoxicity, nephrotoxicity andcardiotoxicity. However, numerous studies in recent years have shown that crotoxin also has immunomodulatory, anti-inflammatory, anti-microbial, anti-tumor and analgesic actions. In this review, we describe the historical background to the discovery of crotoxinand its main toxic activities and then discuss recent structure–function studies and investigations that have led to the identification of novel pharmacological activities for the toxin.

Crotalus cascavella , Crotoxina/farmacologia , Crotoxina/imunologia , Venenos de Serpentes
Toxicon ; 55(6): 1100-1106, Jan 28, 2010.
Artigo em Inglês | Sec. Est. Saúde SP, Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1068252


In the present study, it was investigated which components are responsible for the antiinflammatory properties of Crotalus durissus terrificus venom (CdtV). The effect of crotoxin,as well as of other CdtV components was evaluated on edema, cell migration and alterations in leukocyte–endothelium interactions induced by carrageenan. Crotoxin (40 mg kg 1) was injected at different time periods before or after the injection of carrageenan (15 mg kg 1)into the mouse hind paw, peritoneum or scrotum. Results showed that crotoxin, but not other CdtV components, significantly inhibited inflammatory edema and cell migration when administered before or after carrageenan injection in mice. This toxin also prevented the occurrence of alterations in leukocyte–endothelium interactions induced by carrageenaninjection, such as the increase in adhered cells. In animals pretreated with Boc2 (a selective antagonist of formyl peptide receptors), crotoxin showed neither inhibitoryeffects on edema and cell migration, nor prevented alterations in leukocyte–endothelium interactions induced by carrageenan. These findings demonstrate that crotoxin is thecomponent responsible for the long-lasting anti-inflammatory activity of crude C. durissus terrificus venom, and activation of formyl peptide receptors seems to play a major role inthis effect.

Animais , Ratos , Crotalus cascavella , Crotoxina/antagonistas & inibidores , Crotoxina/efeitos adversos , Serpentes/classificação , Venenos de Serpentes/análise , Venenos de Serpentes/efeitos adversos , Venenos de Serpentes/toxicidade , Carragenina , Inflamação , Inflamação/diagnóstico , Microcirculação
J. venom. anim. toxins incl. trop. dis ; 16(3): 480-492, 2010. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-557177


The basic knowledge on neoplasms is increasing quickly; however, few advances have been achieved in clinical therapy against tumors. For this reason, the development of alternative drugs is relevant in the attempt to improve prognosis and to increase patients' survival. Snake venoms are natural sources of bioactive substances with therapeutic potential. The objective of this work was to identify and characterize the antitumoral effect of Crotalus durissus terrificus venom (CV) and its polypeptide, crotoxin, on benign and malignant tumors, respectively, pituitary adenoma and glioblastoma. The results demonstrated that CV possess a powerful antitumoral effect on benign (pituitary adenoma) and malignant (glioblastoma multiforme) tumors with IC50 values of 0.96 ± 0.11 µg/mL and 2.15 ± 0.2 µg/mL, respectively. This antitumoral effect is cell-cycle-specific and dependent on extracellular calcium, an important factor for crotoxin phospholipase A2 activity. The CV antitumoral effect can be ascribed, at least partially, to the polypeptide crotoxin that also induced brain tumor cell death. In spite of the known CV nephrotoxicity and neurotoxicity, acute treatment with its antitumoral dose established in vitro was not found to be toxic to the analyzed animals. These results indicate the biotechnological potential of CV as a source of pharmaceutical templates for cancer therapy.

Animais , Masculino , Feminino , Ratos , Adenoma , Crotalus cascavella , Neoplasias/terapia , Venenos de Crotalídeos/uso terapêutico , Crotoxina
Artigo em Português | LILACS | ID: lil-560255


O objetivo foi verificar as alterações no estrato córneo em modelos alternativos de membrana após a aplicação de ativos hidratantes envolvendo métodos biofísicos. O modelo de biomembrana utilizado foi a muda de pele de Crotalus durissus e os ativos hidratantes foram: uréia, silício orgânico, extrato vegetal de Imperata cylindrica, reação de xilitol e glicose e componentes de NMF. Os resultados da avaliação das alterações do modelo por meio de Espectroscopia Raman com Transformada de Fourier sugerem que os ativos hidratantes confirmam segurança necessária, pois não alteraram de forma acentuada a estrutura do estrato córneo. Utilizando-se Calorimetria Exploratória Diferencial pode-se indicar que a solução de silício orgânico e o gel hidrofílico com uréia apresentaram melhor poder hidratante.

The objective of this research was to use biophysical techniques to investigate the alterations induced in a biomembrane model of the stratum corneum by the application of moisturizers. The biomembrane was obtained from the skin shed by the rattlesnake Crotalus durissus and the active moisturizing compounds were: urea, dimethylsilanol hyaluronate, Imperata cylindrical plant extract, carbohydrates and natural moisturizing factors (NMF components). Results from FT-Raman spectroscopy suggested that the moisturizers were safe, since they did not promote modifications in the structure of the stratum corneum. Differential scanning calorimetry results indicated that the solution containing the organic silicon compound and the gel with urea showed the best hydrating effects on the stratum corneum.

Humanos , Análise Espectral Raman/instrumentação , Crotalus cascavella/uso terapêutico , Higroscópicos
Toxicon ; 56(3): 402-410, 2010.
Artigo em Inglês | Sec. Est. Saúde SP, Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1068255


Crotalus durissus terrificus envenomation has been associated with direct nephrotoxicity, rhabdomyolysis, hyperuricemia, urinary hypoosmolality, alterations in aminopeptidaseactivities (AP) and oxidative stress. This study evaluated the effects of lipoic acid (LA) on renal function, lethality, AP and GSSG/GSH in mice injected with C. d. terrificus venom (vCdt). The doses and routes of administration of LA and vCdt promoted no systemic myotoxicity. LA did not alter significantly the lethality of vCdt. In nonenvenomed, LA induced hypercreatinemia, urinary hyperosmolality, decrease of urinary urea and creatinine, increase of protein in plasma and in soluble fraction (SF) and decrease in membraneboundfraction (MF) of cortex and medulla. Decreased levels of all AP (except neutral-AP in MF-medulla) were also induced by LA in nonenvenomed. LA associated with vCdt decreased plasma osmolality, hematocrit, urinary uric acid, but increased urinary and SF-medullar protein. LA mitigated the increase of protein in SF-cortex and corrected hyperuricemia, GSSG/GSH and protein in MF-cortex and MF-medulla, as well as decreased plasma neutral AP and acid AP in MF-medulla of envenomed mice. Data suggest that LA contributes to the solubilization/remotion of proteins in MF with impairment of most AP,but it could be beneficial for the treatment of the direct nephrotoxicity of vCdt.

Animais , Ratos , Crotalus cascavella , Estresse Oxidativo , Mordeduras de Serpentes , Venenos de Serpentes/toxicidade , Insuficiência Renal Crônica , Peptídeo Hidrolases , Ácido Tióctico
Pesqui. vet. bras ; 28(6): 261-270, jun. 2008. ilus, tab
Artigo em Português | LILACS | ID: lil-489050


Reproduziu-se experimentalmente o envenenamento crotálico, através da inoculação, por via subcutânea, do veneno de Crotalus durissus terrificus (cascavel sul-americana) em dez bovinos mestiços. Dois animais foram utilizados como controle. O bovino que recebeu dose de 0,03mg/kg de peso corporal, morreu 7h40min após a inoculação. A dose de 0,015mg/kg causou a morte em quatro de sete bovinos inoculados, enquanto os dois animais que receberam 0,0075mg/kg adoeceram discretamente e se recuperaram. Os sintomas tiveram início entre 1h30min e 13h45min após a inoculação. A evolução oscilou entre 5h25min e 45h para os animais que morreram e entre 33h15min e 17 dias entre os animais que se recuperaram. Os principais sinais nervosos observados foram diminuição da resposta aos estímulos externos, reflexos hipotônicos, arrastar dos cascos no solo, aparente apatia, paralisia do globo ocular e da língua, decúbito esternal e lateral. Verificaram-se também adipsia e, por vezes, petéquias nas mucosas vaginal e conjuntival. Houve discreto a moderado aumento do tempo de sangramento e moderado aumento do tempo de tromboplastina parcial ativada. Houve moderada leucocitose com neutrofilia, linfopenia relativa, eosinopenia, monocitose e discreto aumento do número de bastões. Foi evidenciado significativo aumento dos níveis séricos de creatinaquinase, contudo, não foram observadas alterações significativas através da urinálise. À necropsia constataram-se edema quase imperceptível no local da inoculação, discretas petéquias e sufusões no epicárdio, omento, vesícula biliar e mucosa da bexiga em alguns dos animais envenenados experimentalmente. Os exames histopatológicos revelaram necrose (hialinização) de grupos de miócitos ou em miócitos isolados em dez diferentes músculos esqueléticos examinados, próximos ou distantes do local de inoculação em todos os animais necropsiados. Concluí-se que o envenenamento por Crotalus Sul-americanas em bovinos não cursa com mioglobinúria...

Crotalus poisoning was experimentally reproduced by subcutaneous inoculation of Crotalus durissus terrificus (South American rattlesnake) venom into 10 clinically healthy mixed bred 12 to 36-month-old cattle, weighing 125 to 449 kg. Two animals were used as controls. The animal that received a dose of 0.03mg/kg body weight died 7h40min after inoculation. A 0.015mg/kg dose provoked death in 4 out of 7 young oxen. Two animals given 0.0075mg/kg became slightly sick and recovered. Onset of symptoms occurred from 1h30min to 13h45min after inoculation. The clinical course varied from 5h25min to 45h for animals that died, and from 33h15min to 17 days for animals that recovered. The main nervous signs observed were diminished response to external stimuli, hypotonic reflexes, dragging of the hooves, apathy, difficulties in moving around obstacles, ocular globe paralysis, lateral and sternal decubitus, and tongue paralysis. Adipsia and sometimes petechiae in the conjunctival and vaginal mucosa were observed. A slight to moderate increase in bleeding time was noted in 6 animals, and a moderate increase in partial thromboplastin time was found in 7 others. Moderate leukocytosis with neutrophilia, relative lymphopenia, eosinopenia, and monocytosis was found. There was a significant increase in creatine kinase serum levels of a ten-fold order. No significant alterations were revealed by urinalysis. Necropsy revealed minimal edema at the inoculation site, few petechiae and equimoses in the epicardium, omentum, biliary vesicle and bladder mucosa of some animals. Histopathological examination revealed necrosis (hyalinization) of groups or isolated myocytes in different muscles examined, both near and far from the inoculation site, in all animals. The diagnosis of Crotalus poisoning and its differentiation from diseases causing paralysis and muscular necrosis in cattle in Brazil are discussed.

Animais , Masculino , Feminino , Bovinos , Bovinos , Crotalus cascavella/administração & dosagem , Crotalus cascavella/sangue , Crotalus cascavella/toxicidade , Envenenamento/epidemiologia , Envenenamento/patologia , Evolução Clínica/veterinária , Venenos de Crotalídeos/toxicidade