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1.
Pesqui. vet. bras ; 42: e07105, 2022. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1386822

Resumo

In Brazil, snakebites are often cited as a cause of mortality in ruminants, but there are discrepancies in the literature regarding its actual prevalence, either by lack of diagnosis or by mistakes in the differential diagnosis. Among the factors that hinder the diagnosis are included the inconsistencies to distinguish between accidents caused by Bothrops and Crotalus, responsible for over 90% of the cases. For the diagnosis of accidents involving Lachesis muta, both the neurotropic and the proteolytic/hemolytic effects must be considered, similar to what is described in Crotalus scutulatus. This article describes the main clinical, pathological, and laboratory findings observed in envenoming by the aforementioned snakes and suggests procedures for establishing the diagnosis and differential diagnosis starting from a logical sequence, based on epidemiological evidence, clinical, laboratory, and pathological findings.


No Brasil, acidentes ofídicos são frequentemente citados como causa de mortalidade em ruminantes, mas existem discrepâncias em relação a sua atual prevalência, seja por falta de diagnóstico ou por erros no diagnóstico diferencial. Entre os fatores que dificultam o diagnóstico estão as inconsistências para distinguir entre os acidentes causados por Bothrops e Crotalus, responsáveis por mais de 90% dos casos. Para o diagnóstico de envenenamentos por Lachesis muta, devem ser considerados os efeitos neurotrópico e proteolítico/hemolíticos concomitantes, a exemplo do que ocorre com algumas cascavéis norte-americanas (Crotalus scutulatus, entre elas). Este artigo descreve os principais achados clinicopatológicos e laboratoriais observados em casos de envenenamento pelas serpentes citadas e sugere um roteiro simplificado para o estabelecimento do diagnóstico e diagnóstico diferencial, a partir de uma sequência lógica, baseada em evidências epidemiológicas e achados clínicos, laboratoriais e patológicos.


Assuntos
Animais , Mordeduras de Serpentes/diagnóstico , Mordeduras de Serpentes/mortalidade , Crotalus , Bothrops , Mordeduras de Serpentes/veterinária , Ruminantes
2.
J. venom. anim. toxins incl. trop. dis ; 26: e20190053, 2020. graf, mapas, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1091020

Resumo

Abstract Background: Crotalus durissus is considered one of the most important species of venomous snakes in Brazil, due to the high mortality of its snakebites. The venom of Crotalus durissus contains four main toxins: crotoxin, convulxin, gyroxin and crotamine. Venoms can vary in their crotamine content, being crotamine-negative or -positive. This heterogeneity is of great importance for producing antivenom, due to their different mechanisms of action. The possibility that antivenom produced by Butantan Institute might have a different immunorecognition capacity between crotamine-negative and crotamine-positive C. durissus venoms instigated us to investigate the differences between these two venom groups. Methods: The presence of crotamine was analyzed by SDS-PAGE, western blotting and ELISA, whereas comparison between the two types of venoms was carried out through HPLC, mass spectrometry analysis as well as assessment of antivenom lethality and efficacy. Results: The results showed a variation in the presence of crotamine among the subspecies and the geographic origin of snakes from nature, but not in captive snakes. Regarding differences between crotamine-positive and -negative venoms, some exclusive proteins are found in each pool and the crotamine-negative pool presented more phospholipase A2 than crotamine-positive pool. This variation could affect the time to death, but the lethal and effective dose were not affected. Conclusion: These differences between venom pools indicate the importance of using both, crotamine-positive and crotamine-negative venoms, to produce the antivenom.(AU)


Assuntos
Animais , Antivenenos , Crotalus , Venenos de Crotalídeos/análise , Distribuição Animal
3.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 26: e20200016, 2020. graf
Artigo em Inglês | VETINDEX | ID: vti-32213

Resumo

South American rattlesnakes are represented in Brazil by a single species, Crotalus durissus, which has public health importance due to the severity of its envenomation and to its wide geographical distribution. The species is subdivided into several subspecies, but the current classification is controversial. In Brazil, the venoms of C. d. terrificus and C. d. collilineatus are used for hyperimmunization of horses for antivenom production, even though the distinction of these two subspecies are mostly by their geographical distribution. In this context, we described a comparative compositional and functional characterization of individual C. d. collilineatus and C. d. terrificus venoms from three Brazilian states. Methods: We compared the compositional patterns of C. d. terrificus and C. d. collilineatus individual venoms by 1-DE and RP-HPLC. For functional analyzes, the enzymatic activities of PLA2, LAAO, and coagulant activity were evaluated. Finally, the immunorecognition of venom toxins by the crotalic antivenom produced at Butantan Institute was evaluated using Western blotting. Results: The protein profile of individual venoms from C. d. collilineatus and C. d. terrificus showed a comparable overall composition, despite some intraspecific variation, especially regarding crotamine and LAAO. Interestingly, HPLC analysis showed a geographic pattern concerning PLA2. In addition, a remarkable intraspecific variation was also observed in PLA2, LAAO and coagulant activities. The immunorecognition pattern of individual venoms from C. d. collilineatus and C. d. terrificus by crotalic antivenom produced at Butantan Institute was similar. Conclusions: The results highlighted the individual variability among the venoms of C. durissus ssp. specimens. Importantly, our data point to a geographical variation of C. durissus ssp. venom profile, regardless of the subspecies, as evidenced by PLA2 isoforms complexity, which may explain the increase in venom neurotoxicity from Northeastern through Southern Brazil reported for the species.(AU)


Assuntos
Animais , Venenos de Serpentes/análise , Venenos de Serpentes/classificação , Características de Residência , Crotalus
4.
Acta sci. vet. (Impr.) ; 48(suppl.1): Pub.521-4 jan. 2020. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1458348

Resumo

Background: South American rattlesnake (Crotalus durissus spp.) envenomation is rarely reported in small animals andlivestock in Brazil. Minor swelling at the snakebite site, skeletal muscle, and renal damage, and severe neurological signscharacterize the crotalic envenomation. This case report aims to present epidemiological, clinical, and pathological dataof two cases of Crotalus durissus spp envenomation in dogs in the Northeast of Brazil.Cases: Envenomation by Crotalus durissus spp. was recorded in two dogs in Patos, State of Paraíba, Brazil. In Case 1,the dog presented flaccid paralysis, hyporeflexia, a deficit of cranial nerves, epistaxis, and gingival hemorrhages. Laboratory assay showed proteinuria, myoglobinuria, regenerative thrombocytopenia, and increased serum activities of creatinekinase (CK), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP). The dogwas medicated with crotalic antivenom and wholly recovered from local and systemic clinical signs. In Case 2, the dogdied and was detected fang marks at the ventral region of the left mandible (two small parallel perforations spaced 2.0 cmapart) at the snakebite site. Cyanosis of the oral cavity, congestion, and hemorrhages in several organs were observed atnecropsy. Tubular nephrosis, muscular necrosis, hepatocytes swelling were observed. The owners witnessed snakebites,and the rattlesnakes (Crotalus durissus spp.) identified by the rattle at the end portion of the tail in both cases.Discussion: Natural South American rattlesnake envenomation presents complex clinical signs that makes diagnosis achallenge for veterinary practitioners. The criteria for the correct diagnosis and observed in the two dogs include witness ofthe snakebite, identification of the snake, detection of fang marks, clinical-pathological findings, and therapeutic responseto treatment with specific anti-venom....


Assuntos
Animais , Cães , Doenças Musculares/veterinária , Mordeduras de Serpentes/epidemiologia , Mordeduras de Serpentes/patologia , Venenos de Crotalídeos , Brasil , Crotalus
5.
Acta sci. vet. (Online) ; 48(suppl.1): Pub. 521, July 19, 2020. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-31873

Resumo

Background: South American rattlesnake (Crotalus durissus spp.) envenomation is rarely reported in small animals andlivestock in Brazil. Minor swelling at the snakebite site, skeletal muscle, and renal damage, and severe neurological signscharacterize the crotalic envenomation. This case report aims to present epidemiological, clinical, and pathological dataof two cases of Crotalus durissus spp envenomation in dogs in the Northeast of Brazil.Cases: Envenomation by Crotalus durissus spp. was recorded in two dogs in Patos, State of Paraíba, Brazil. In Case 1,the dog presented flaccid paralysis, hyporeflexia, a deficit of cranial nerves, epistaxis, and gingival hemorrhages. Laboratory assay showed proteinuria, myoglobinuria, regenerative thrombocytopenia, and increased serum activities of creatinekinase (CK), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP). The dogwas medicated with crotalic antivenom and wholly recovered from local and systemic clinical signs. In Case 2, the dogdied and was detected fang marks at the ventral region of the left mandible (two small parallel perforations spaced 2.0 cmapart) at the snakebite site. Cyanosis of the oral cavity, congestion, and hemorrhages in several organs were observed atnecropsy. Tubular nephrosis, muscular necrosis, hepatocytes swelling were observed. The owners witnessed snakebites,and the rattlesnakes (Crotalus durissus spp.) identified by the rattle at the end portion of the tail in both cases.Discussion: Natural South American rattlesnake envenomation presents complex clinical signs that makes diagnosis achallenge for veterinary practitioners. The criteria for the correct diagnosis and observed in the two dogs include witness ofthe snakebite, identification of the snake, detection of fang marks, clinical-pathological findings, and therapeutic responseto treatment with specific anti-venom....(AU)


Assuntos
Animais , Cães , Venenos de Crotalídeos , Mordeduras de Serpentes/epidemiologia , Mordeduras de Serpentes/patologia , Doenças Musculares/veterinária , Brasil , Crotalus
6.
J. venom. anim. toxins incl. trop. dis ; 26: e20200016, 2020. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1135158

Resumo

South American rattlesnakes are represented in Brazil by a single species, Crotalus durissus, which has public health importance due to the severity of its envenomation and to its wide geographical distribution. The species is subdivided into several subspecies, but the current classification is controversial. In Brazil, the venoms of C. d. terrificus and C. d. collilineatus are used for hyperimmunization of horses for antivenom production, even though the distinction of these two subspecies are mostly by their geographical distribution. In this context, we described a comparative compositional and functional characterization of individual C. d. collilineatus and C. d. terrificus venoms from three Brazilian states. Methods: We compared the compositional patterns of C. d. terrificus and C. d. collilineatus individual venoms by 1-DE and RP-HPLC. For functional analyzes, the enzymatic activities of PLA2, LAAO, and coagulant activity were evaluated. Finally, the immunorecognition of venom toxins by the crotalic antivenom produced at Butantan Institute was evaluated using Western blotting. Results: The protein profile of individual venoms from C. d. collilineatus and C. d. terrificus showed a comparable overall composition, despite some intraspecific variation, especially regarding crotamine and LAAO. Interestingly, HPLC analysis showed a geographic pattern concerning PLA2. In addition, a remarkable intraspecific variation was also observed in PLA2, LAAO and coagulant activities. The immunorecognition pattern of individual venoms from C. d. collilineatus and C. d. terrificus by crotalic antivenom produced at Butantan Institute was similar. Conclusions: The results highlighted the individual variability among the venoms of C. durissus ssp. specimens. Importantly, our data point to a geographical variation of C. durissus ssp. venom profile, regardless of the subspecies, as evidenced by PLA2 isoforms complexity, which may explain the increase in venom neurotoxicity from Northeastern through Southern Brazil reported for the species.(AU)


Assuntos
Animais , Crotalus , Venenos Elapídicos , Fosfolipases A2 , Localizações Geográficas
7.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 26: e20190053, Apr. 6, 2020. ilus, mapas, graf
Artigo em Inglês | VETINDEX | ID: vti-25941

Resumo

Background:Crotalus durissus is considered one of the most important species of venomous snakes in Brazil, due to the high mortality of its snakebites. The venom of Crotalus durissus contains four main toxins: crotoxin, convulxin, gyroxin and crotamine. Venoms can vary in their crotamine content, being crotamine-negative or -positive. This heterogeneity is of great importance for producing antivenom, due to their different mechanisms of action. The possibility that antivenom produced by Butantan Institute might have a different immunorecognition capacity between crotamine-negative and crotamine-positive C. durissus venoms instigated us to investigate the differences between these two venom groups. Methods:The presence of crotamine was analyzed by SDS-PAGE, western blotting and ELISA, whereas comparison between the two types of venoms was carried out through HPLC, mass spectrometry analysis as well as assessment of antivenom lethality and efficacy. Results:The results showed a variation in the presence of crotamine among the subspecies and the geographic origin of snakes from nature, but not in captive snakes. Regarding differences between crotamine-positive and -negative venoms, some exclusive proteins are found in each pool and the crotamine-negative pool presented more phospholipase A2 than crotamine-positive pool. This variation could affect the time to death, but the lethal and effective dose were not affected. Conclusion:These differences between venom pools indicate the importance of using both, crotamine-positive and crotamine-negative venoms, to produce the antivenom.(AU)


Assuntos
Animais , Crotalus/anatomia & histologia , Crotalus/classificação , Crotalus/genética , Venenos de Crotalídeos/antagonistas & inibidores , Antivenenos
8.
Zoologia (Curitiba, Impr.) ; 36: e.29587, Apr. 18, 2019. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1504568

Resumo

There are few studies about parasitic infections in Crotalus triseriatus (Wagler, 1830), an endemic rattlesnake from the highlands of central Mexico. This species occupies several habitats, from conserved forested regions to heavily impacted landscapes. To increase the parasitological knowledge of this reptile species without impacting populations, we obtained fecal samples of 16 rattlesnakes between 2012 and 2014 from Toluca Valley, Mexico. By using flotation technique, we found oocysts of Eimeria sp. and eggs of Capillariidae sp. The most frequent parasite was Eimeria sp. (62.5%). This study provides the first records of occurrence of parasites in reptilian feces from Mexico. Our results may be important for wildlife conservation purposes, for example, they could indicate of the population health of this species during processes of translocation.


Assuntos
Animais , Coccídios , Contagem de Ovos de Parasitas/veterinária , Crotalus/parasitologia , Fezes/parasitologia , México
9.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1002503

Resumo

The prevalent class of snake venom serine proteases (SVSP) in Viperidae venoms is the thrombin-like enzymes, which, similarly to human thrombin, convert fibrinogen into insoluble fibrin monomers. However, thrombin-like serine proteases differ from thrombin by being unable to activate factor XIII, thus leading to the formation of loose clots and fibrinogen consumption. We report the functional and biological characterization of a recombinant thrombin-like serine protease from Crotalus durissus collilineatus, named rCollinein-1. Methods: Heterologous expression of rCollinein-1 was performed in Pichia pastoris system according to a previously standardized protocol, with some modifications. rCollinein-1 was purified from the culture medium by a combination of three chromatographic steps. The recombinant toxin was tested in vitro for its thrombolytic activity and in mice for its edematogenicity, blood incoagulability and effect on plasma proteins. Results: When tested for the ability to induce mouse paw edema, rCollinein-1 demonstrated low edematogenic effect, indicating little involvement of this enzyme in the inflammatory processes resulting from ophidian accidents. The rCollinein-1 did not degrade blood clots in vitro, which suggests that this toxin lacks fibrinolytic activity and is not able to directly or indirectly activate the fibrinolytic system. The minimal dose of rCollinein-1 that turns the blood incoagulable in experimental mice is 7.5 mg/kg. The toxin also led to a significant increase in activated partial thromboplastin time at the dose of 1 mg/kg in the animals. Other parameters such as plasma fibrinogen concentration and prothrombin time were not significantly affected by treatment with rCollinein-1 at this dose. The toxin was also able to alter plasma proteins in mouse after 3 h of injection at a dose of 1 mg/kg, leading to a decrease in the intensity of beta zone and an increase in gamma zone in agarose gel electrophoresis Conclusion: These results suggest that the recombinant enzyme has no potential as a thrombolytic agent but can be applied in the prevention of thrombus formation in some pathological processes and as molecular tools in studies related to hemostasis.(AU)


Assuntos
Venenos de Serpentes , Produtos Biológicos , Trombina , Crotalus , Serina Proteases , Relatório de Pesquisa
10.
Zoologia (Curitiba) ; 36: e.29587, Oct. 21, 2019. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-24622

Resumo

There are few studies about parasitic infections in Crotalus triseriatus (Wagler, 1830), an endemic rattlesnake from the highlands of central Mexico. This species occupies several habitats, from conserved forested regions to heavily impacted landscapes. To increase the parasitological knowledge of this reptile species without impacting populations, we obtained fecal samples of 16 rattlesnakes between 2012 and 2014 from Toluca Valley, Mexico. By using flotation technique, we found oocysts of Eimeria sp. and eggs of Capillariidae sp. The most frequent parasite was Eimeria sp. (62.5%). This study provides the first records of occurrence of parasites in reptilian feces from Mexico. Our results may be important for wildlife conservation purposes, for example, they could indicate of the population health of this species during processes of translocation.(AU)


Assuntos
Animais , Fezes/parasitologia , Contagem de Ovos de Parasitas/veterinária , Crotalus/parasitologia , Coccídios , México
11.
Acta sci. vet. (Online) ; 47: Pub. 1662, May 30, 2019. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-19610

Resumo

Background: Accidents caused by venom of Crotalus durissus snakes, popularly known in Brazil as rattlesnake, aresecond in relation to the occurrence and first place in deaths in humans and animals, mainly due to the great neurotoxic,myotoxic, coagulant, nephrotoxic and hepatotoxic potential of their venom. The effects observed are due to the action ofthe main poison fractions and among them we can mention crotoxin (representing 50% of the total poison), crotamine,gyroxine and conxulxin. The present study aimed to analyze the liver of experimentally poisoned Wistar rats with venomof Crotalus durissus terrificus by means of histological and fractal analysis. The hypothesis is that the venom of Crotalusdurissus terrificus is can induce hepatic damage at the dose recommended in this study, that its alterations can be quantifiedby the fractal dimension and that the antiofidic serum botropic crotalic be able to minimize the hepatic lesions inducedby the venom.Materials, Methods & Results: Ninety rats were distributed into different groups and treated with: control group (GC, n= 30) 0.9% sodium chloride solution; venom group (GV, n = 30) crotalic venom at the dose of 1 mg/kg; (GVS, n = 30)crotalic venom at the dose of 1 mg/Kg and antiofidic serum 6 h after the application of the venom at the dose recommendedby the manufacturer. Liver samples were collected at 2 h (M1), 8 h (M2) and 24 h (M3) after venom administration andsubmitted to histological analysis and fractal dimension (DF) using the ImageJ® software and box-counting method. Procedures for collecting, processing and analyzing samples were standardized. For statistical analyzes, after the normalitywas verified by the Shapiro-Wilk test and homogeneity by the Bartlett test, the data were submitted to analysis of variance(ANOVA) with Duncan test contrast with a significance level of 5%. No significant lesions were observed in GC, howevernecrosis...(AU)


Assuntos
Animais , Ratos , Ratos Wistar , Fígado/anatomia & histologia , Venenos de Crotalídeos/análise , Crotalus , Fractais , Análise de Variância
12.
Acta sci. vet. (Impr.) ; 47: Pub.1662-2019. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1458060

Resumo

Background: Accidents caused by venom of Crotalus durissus snakes, popularly known in Brazil as rattlesnake, aresecond in relation to the occurrence and first place in deaths in humans and animals, mainly due to the great neurotoxic,myotoxic, coagulant, nephrotoxic and hepatotoxic potential of their venom. The effects observed are due to the action ofthe main poison fractions and among them we can mention crotoxin (representing 50% of the total poison), crotamine,gyroxine and conxulxin. The present study aimed to analyze the liver of experimentally poisoned Wistar rats with venomof Crotalus durissus terrificus by means of histological and fractal analysis. The hypothesis is that the venom of Crotalusdurissus terrificus is can induce hepatic damage at the dose recommended in this study, that its alterations can be quantifiedby the fractal dimension and that the antiofidic serum botropic crotalic be able to minimize the hepatic lesions inducedby the venom.Materials, Methods & Results: Ninety rats were distributed into different groups and treated with: control group (GC, n= 30) 0.9% sodium chloride solution; venom group (GV, n = 30) crotalic venom at the dose of 1 mg/kg; (GVS, n = 30)crotalic venom at the dose of 1 mg/Kg and antiofidic serum 6 h after the application of the venom at the dose recommendedby the manufacturer. Liver samples were collected at 2 h (M1), 8 h (M2) and 24 h (M3) after venom administration andsubmitted to histological analysis and fractal dimension (DF) using the ImageJ® software and box-counting method. Procedures for collecting, processing and analyzing samples were standardized. For statistical analyzes, after the normalitywas verified by the Shapiro-Wilk test and homogeneity by the Bartlett test, the data were submitted to analysis of variance(ANOVA) with Duncan test contrast with a significance level of 5%. No significant lesions were observed in GC, howevernecrosis...


Assuntos
Animais , Ratos , Crotalus , Fígado/anatomia & histologia , Ratos Wistar , Venenos de Crotalídeos/análise , Análise de Variância , Fractais
13.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 25: e147118, Apr. 8, 2019. graf
Artigo em Inglês | VETINDEX | ID: vti-19277

Resumo

Background:The prevalent class of snake venom serine proteases (SVSP) in Viperidae venoms is the thrombin-like enzymes, which, similarly to human thrombin, convert fibrinogen into insoluble fibrin monomers. However, thrombin-like serine proteases differ from thrombin by being unable to activate factor XIII, thus leading to the formation of loose clots and fibrinogen consumption. We report the functional and biological characterization of a recombinant thrombin-like serine protease from Crotalus durissus collilineatus, named rCollinein-1.Methods:Heterologous expression of rCollinein-1 was performed in Pichia pastoris system according to a previously standardized protocol, with some modifications. rCollinein-1 was purified from the culture medium by a combination of three chromatographic steps. The recombinant toxin was tested in vitro for its thrombolytic activity and in mice for its edematogenicity, blood incoagulability and effect on plasma proteins.Results:When tested for the ability to induce mouse paw edema, rCollinein-1 demonstrated low edematogenic effect, indicating little involvement of this enzyme in the inflammatory processes resulting from ophidian accidents. The rCollinein-1 did not degrade blood clots in vitro, which suggests that this toxin lacks fibrinolytic activity and is not able to directly or indirectly activate the fibrinolytic system. The minimal dose of rCollinein-1 that turns the blood incoagulable in experimental mice is 7.5 mg/kg. The toxin also led to a significant increase in activated partial thromboplastin time at the dose of 1 mg/kg in the animals. Other parameters such as plasma fibrinogen concentration and prothrombin time were not significantly affected by treatment with rCollinein-1 at this dose. The toxin was also able to alter plasma proteins in mouse after 3 h of injection at a dose of 1 mg/kg, leading to a decrease in the intensity of beta zone and an increase in gamma zone in agarose gel electrophoresis...(AU)


Assuntos
Animais , Camundongos , Crotalus , Serina Proteases , Venenos de Crotalídeos/química , Trombina , Agentes de Coagulação
14.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-976024

Resumo

In recent decades, snake venom disintegrins have received special attention due to their potential use in anticancer therapy. Disintegrins are small and cysteine-rich proteins present in snake venoms and can interact with specific integrins to inhibit their activities in cell-cell and cell-ECM interactions. These molecules, known to inhibit platelet aggregation, are also capable of interacting with certain cancer-related integrins, and may interfere in important processes involved in carcinogenesis. Therefore, disintegrin from Crotalus durissus collilineatus venom was isolated, structurally characterized and evaluated for its toxicity and ability to interfere with cell proliferation and migration in MDA-MB-231, a human breast cancer cell line. Methods: Based on previous studies, disintegrin was isolated by FPLC, through two chromatographic steps, both on reversed phase C-18 columns. The isolated disintegrin was structurally characterized by Tris-TricineSDS-PAGE, mass spectrometry and N-terminal sequencing. For the functional assays, MTT and wound-healing assays were performed in order to investigate cytotoxicity and effect on cell migration in vitro, respectively. Results: Disintegrin presented a molecular mass of 7287.4 Da and its amino acid sequence shared similarity with the disintegrin domain of P-II metalloproteases. Using functional assays, the disintegrin showed low cytotoxicity (15% and 17%, at 3 and 6 µg/mL, respectively) after 24 h of incubation and in the wound-healing assay, the disintegrin (3 µg/mL) was able to significantly inhibit cell migration (24%, p < 0.05), compared to negative control. Conclusion: Thus, our results demonstrate that non-RGD disintegrin from C. d. collilineatus induces low cytotoxicity and inhibits migration of human breast cancer cells. Therefore, it may be a very useful molecular tool for understanding ECM-cell interaction cancer-related mechanisms involved in an important integrin family that highlights molecular aspects of tumorigenesis. Also, non-RGD disintegrin has potential to serve as an agent in anticancer therapy or adjuvant component combined with other anticancer drugs.(AU)


Assuntos
Venenos de Serpentes , Crotalus , Desintegrinas , Neoplasias da Mama
15.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1040379

Resumo

Our group has previously performed a proteomic study verifying that individual variations can occur among Crotalus durissus collilineatus venoms. These variations may lead to differences in venom toxicity and may result in lack of neutralization of some components by antivenom. In this way, this study aimed to evaluate the Brazilian anticrotalic serum capacity in recognizing twenty-two Crotalus durissus collilineatus venoms, as well as their fractions. Methods: The indirect enzyme-linked immunosorbent assay (ELISA) was chosen to evaluate the efficacy of heterologous anticrotalic serum produced by Instituto Butantan (Brazil) in recognizing the twenty-two Crotalus durissus collilineatus venoms and the pool of them. Moreover, the venom pool was fractionated using reversed-phase fast protein liquid chromatography (RP-FPLC) and the obtained fractions were analyzed concerning antivenom recognition. Results: Evaluation of venom variability by ELISA showed that all venom samples were recognized by the Brazilian anticrotalic antivenom. However, some particular venom fractions were poorly recognized. Conclusion: This study demonstrated that the Brazilian anticrotalic serum recognizes all the different twenty-two venoms of C. d. collilineatus and their fractions, although in a quantitatively different way, which may impact the effectiveness of the antivenom therapy. These results confirm the need to use a pool of venoms with the greatest possible variability in the preparation of antivenoms, in order to improve their effectiveness.(AU)


Assuntos
Antivenenos/toxicidade , Crotalus , Venenos de Crotalídeos , Ensaio de Imunoadsorção Enzimática
16.
Ciênc. anim. bras. (Impr.) ; 19: 51322, 2018. ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1473633

Resumo

Snake venoms are recognized as a promising source of pharmacologically active substances and are potentially useful for the development of new antimicrobial drugs. This study aimed to investigate the antimicrobial activity of the venom from the rattlesnake Crotalus durissus terrificus against several bacteria. Antibacterial activity was determined by using the plate microdilution method and the activity on the bacterial envelope structure was screened by using the crystal violet assay. The proteins in crude venom were separated by electrophoresis and characterized regarding their proteolytic activity. C. d. terrificus venom exhibited antimicrobial action against gram-positive and gram-negative bacteria. MIC values were defined for Pseudomonas aeruginosa ATCC 27853 (62.5 µg/mL), Staphylococcus aureus ATCC 25923 (125 µg/mL), and Micrococcus luteus ATCC 9341 (≤500 µg/mL). For Salmonella enterica serovar typhimurium ATCC 14028 and Corynebacterium glutamicum ATCC 13032, the decrease in bacterial growth was not detected visually, but was statistically significant. The crystal violet assay demonstrated that the crude venom increased bacterial cell permeability and the secreted protein profile agreed with previous reports. The results suggest that the proteins with lytic activity against bacteria in C. d. terrificus venom deserve further characterization as they may offer reinforcements to the weak therapeutic arsenal used to fight microbial multidrug resistance.


Os venenos de serpentes são reconhecidos como uma fonte promissora de substâncias farmacologicamente ativas e potencialmente úteis para o desenvolvimento de novas drogas antimicrobianas. Esse trabalho teve como objetivo investigar a atividade antimicrobiana do veneno de Crotalus durissus terrificus contra várias bactérias. A determinação da atividade antibacteriana foi realizada pelo método de microdiluição em placas e a ação na estrutura do envelope bacteriano pelo ensaio violeta de cristal. As proteínas do extrato bruto foram separadas por eletroforese e caracterizadas quanto à sua atividade proteolítica. O veneno de C. d. terrificus apresentou ação antimicrobiana frente bactérias gram-positivas e gram-negativas. Os valores de MIC foram definidos para Pseudomonas aeruginosa ATCC 27853 (62.5 µg/ mL), Staphylococcus aureus ATCC 25923 (125 µg/mL) e Micrococcus luteus ATCC 9341 (≤ 500 µg/mL). Para Salmonella enterica serovar typhimurium ATCC 14028 e Corynebacterium glutamicum ATCC 13032, o decréscimo no crescimento bacteriano não foi detectado visualmente, mas foi estatisticamente significante. O teste do cristal violeta demonstrou que o veneno bruto aumentou a permeabilidade das células bacterianas e o perfil de proteína secretada está em consonância com relatos anteriores. Os resultados sugerem que as proteínas com atividade lítica contra bactérias no veneno de C. d. terrificus merecem atenção para uma melhor caracterização, uma vez que podem trazer reforços para o escasso arsenal terapêutico empregado para combater a multirresistência microbiana.


Assuntos
Animais , Anti-Infecciosos/análise , Crotalus , Venenos de Crotalídeos/análise , Farmacorresistência Bacteriana Múltipla
17.
Ci. Anim. bras. ; 19: e-51322, 2018. ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-18580

Resumo

Snake venoms are recognized as a promising source of pharmacologically active substances and are potentially useful for the development of new antimicrobial drugs. This study aimed to investigate the antimicrobial activity of the venom from the rattlesnake Crotalus durissus terrificus against several bacteria. Antibacterial activity was determined by using the plate microdilution method and the activity on the bacterial envelope structure was screened by using the crystal violet assay. The proteins in crude venom were separated by electrophoresis and characterized regarding their proteolytic activity. C. d. terrificus venom exhibited antimicrobial action against gram-positive and gram-negative bacteria. MIC values were defined for Pseudomonas aeruginosa ATCC 27853 (62.5 µg/mL), Staphylococcus aureus ATCC 25923 (125 µg/mL), and Micrococcus luteus ATCC 9341 (≤500 µg/mL). For Salmonella enterica serovar typhimurium ATCC 14028 and Corynebacterium glutamicum ATCC 13032, the decrease in bacterial growth was not detected visually, but was statistically significant. The crystal violet assay demonstrated that the crude venom increased bacterial cell permeability and the secreted protein profile agreed with previous reports. The results suggest that the proteins with lytic activity against bacteria in C. d. terrificus venom deserve further characterization as they may offer reinforcements to the weak therapeutic arsenal used to fight microbial multidrug resistance.(AU)


Os venenos de serpentes são reconhecidos como uma fonte promissora de substâncias farmacologicamente ativas e potencialmente úteis para o desenvolvimento de novas drogas antimicrobianas. Esse trabalho teve como objetivo investigar a atividade antimicrobiana do veneno de Crotalus durissus terrificus contra várias bactérias. A determinação da atividade antibacteriana foi realizada pelo método de microdiluição em placas e a ação na estrutura do envelope bacteriano pelo ensaio violeta de cristal. As proteínas do extrato bruto foram separadas por eletroforese e caracterizadas quanto à sua atividade proteolítica. O veneno de C. d. terrificus apresentou ação antimicrobiana frente bactérias gram-positivas e gram-negativas. Os valores de MIC foram definidos para Pseudomonas aeruginosa ATCC 27853 (62.5 µg/ mL), Staphylococcus aureus ATCC 25923 (125 µg/mL) e Micrococcus luteus ATCC 9341 (≤ 500 µg/mL). Para Salmonella enterica serovar typhimurium ATCC 14028 e Corynebacterium glutamicum ATCC 13032, o decréscimo no crescimento bacteriano não foi detectado visualmente, mas foi estatisticamente significante. O teste do cristal violeta demonstrou que o veneno bruto aumentou a permeabilidade das células bacterianas e o perfil de proteína secretada está em consonância com relatos anteriores. Os resultados sugerem que as proteínas com atividade lítica contra bactérias no veneno de C. d. terrificus merecem atenção para uma melhor caracterização, uma vez que podem trazer reforços para o escasso arsenal terapêutico empregado para combater a multirresistência microbiana.(AU)


Assuntos
Animais , Crotalus , Venenos de Crotalídeos/análise , Anti-Infecciosos/análise , Farmacorresistência Bacteriana Múltipla
18.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 24: 34, Dec. 17, 2018. graf
Artigo em Inglês | VETINDEX | ID: vti-19379

Resumo

Background: Our group has previously performed a proteomic study verifying that individual variations can occur among Crotalus durissus collilineatus venoms. These variations may lead to differences in venom toxicity and may result in lack of neutralization of some components by antivenom. In this way, this study aimed to evaluate the Brazilian anticrotalic serum capacity in recognizing twenty-two Crotalus durissus collilineatus venoms, as well as their fractions. Methods: The indirect enzyme-linked immunosorbent assay (ELISA) was chosen to evaluate the efficacy of heterologous anticrotalic serum produced by Instituto Butantan (Brazil) in recognizing the twenty-two Crotalus durissus collilineatus venoms and the pool of them. Moreover, the venom pool was fractionated using reversed-phase fast protein liquid chromatography (RP-FPLC) and the obtained fractions were analyzed concerning antivenom recognition. Results: Evaluation of venom variability by ELISA showed that all venom samples were recognized by the Brazilian anticrotalic antivenom. However, some particular venom fractions were poorly recognized. Conclusion: This study demonstrated that the Brazilian anticrotalic serum recognizes all the different twenty-two venoms of C. d. collilineatus and their fractions, although in a quantitatively different way, which may impact the effectiveness of the antivenom therapy. These results confirm the need to use a pool of venoms with the greatest possible variability in the preparation of antivenoms, in order to improve their effectiveness.(AU)


Assuntos
Animais , Crotalus , Venenos de Crotalídeos/análise , Venenos de Crotalídeos/química , Antivenenos/análise , Ensaio de Imunoadsorção Enzimática
19.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 24: 28, Nov. 29, 2018. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-18439

Resumo

Background:In recent decades, snake venom disintegrins have received special attention due to their potential use in anticancer therapy. Disintegrins are small and cysteine-rich proteins present in snake venoms and can interact with specific integrins to inhibit their activities in cell-cell and cell-ECM interactions. These molecules, known to inhibit platelet aggregation, are also capable of interacting with certain cancer-related integrins, and may interfere in important processes involved in carcinogenesis. Therefore, disintegrin from Crotalus durissus collilineatus venom was isolated, structurally characterized and evaluated for its toxicity and ability to interfere with cell proliferation and migration in MDA-MB-231, a human breast cancer cell line.Methods:Based on previous studies, disintegrin was isolated by FPLC, through two chromatographic steps, both on reversed phase C-18 columns. The isolated disintegrin was structurally characterized by Tris-Tricine-SDS-PAGE, mass spectrometry and N-terminal sequencing. For the functional assays, MTT and wound-healing assays were performed in order to investigate cytotoxicity and effect on cell migration in vitro, respectively.Results:Disintegrin presented a molecular mass of 7287.4 Da and its amino acid sequence shared similarity with the disintegrin domain of P-II metalloproteases. Using functional assays, the disintegrin showed low cytotoxicity (15% and 17%, at 3 and 6 μg/mL, respectively) after 24 h of incubation and in the wound-healing assay, the disintegrin (3 μg/mL) was able to significantly inhibit cell migration (24%, p < 0.05), compared to negative control.Conclusion:Thus, our results demonstrate that non-RGD disintegrin from C. d. collilineatus induces low cytotoxicity and inhibits migration of human breast cancer cells. Therefore, it may be a very useful molecular tool for understanding ECM-cell interaction cancer-related mechanisms involved in...(AU)


Assuntos
Humanos , Animais , Venenos de Crotalídeos/análise , Desintegrinas/análise , Movimento Celular , Adesão Celular , Neoplasias da Mama/tratamento farmacológico , Crotalus
20.
J. venom. anim. toxins incl. trop. dis ; 24: 39, 2018. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-984689

Resumo

For the past 80 years, Crotoxin has become one of the most investigated isolated toxins from snake venoms, partially due to its major role as the main toxic component in the venom of the South American rattlesnake Crotalus durissus terrificus. However, in the past decades, progressive studies have led researchers to shift their focus on Crotoxin, opening novel perspectives and applications as a therapeutic approach. Although this toxin acts on a wide variety of biological events, the modulation of immune responses is considered as one of its most relevant behaviors. Therefore, the present review describes the scientific investigations on the capacity of Crotoxin to modulate anti-inflammatory and immunosuppressive responses, and its application as a medicinal immunopharmacological approach. In addition, this review will also discuss its mechanisms, involving cellular and molecular pathways, capable of improving pathological alterations related to immune-associated disorders.(AU)


Assuntos
Venenos de Serpentes , Produtos Biológicos , Antivenenos , Crotalus , Crotoxina/imunologia , Imunidade , Imunossupressores
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