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Acción del veneno de Bothrops jararacussu de Argentina sobre la coagulación sanguínea
Maru?ak,S.L.; Ruíz de Torrent,R.M.; Teibler,G.P.; Gay,C.C.; Leiva,L.; Acosta de Pérez,O.;
InVet , 2006,
Abstract: the envenomation by snakes of the genus bothrops of argentina causes local and systemic signs. among the systemic damages, bothropic venoms induce a wide variety of effects on blood coagulation, haemorrhage, shock and renal failure. in this paper the effects of bothrops jararacussu venom from argentina on the hemostatic system were determined. in order to estimate blood-clotting, fibrinolytic and defibrinating activities of the venom, in vitro and in vivo tests were employed. the ability to degrade fibrinogen and the lethal dosis (dl50) also were determined. the b. jararacussu venom appears to be fibrinogenolytic and the values obtained for assayed activities were minimum blood-clotting concentration 18,5 μg/ml, minimum fibrinolytic dose 9,5 mg/ml, minimum defibrinating dose 1,56 μg, ld50 43,52 μg/mouse. these results differ from those obtained for other species of genus bothrops, or from the same species that inhabits in different south american regions. it is concluded that bothrops jararacussu venom from argentina largely affects blood coagulation system, and that the procoagulant and anticoagulant activities exhibited by this secretion may contribute to the lethality of the venom, since they could promote hemorrhages which could lead to renal failure and death of the victim in severe envenomation.
Da o renal en ratas inducido por veneno de Bothrops neuwiedii diporus de Argentina Renal injury in rats poisoned by venom of Bothrops neuwiedii diporus from Argentina  [cached]
Patricia Koscinczuk,Juan T. Borda,Silvana Maru?ak,Ofelia Acosta de Perez
Medicina (Buenos Aires) , 2004,
Abstract: La insuficiencia renal aguda es una de las complicaciones sistémicas más frecuentes después de un accidente ofídico. En este estudio se evalúan los efectos que el veneno de Bothrops neuwiedii diporus produce en el ri ón de ratas machos de la cepa Wistar. La histopatología permitió comprobar el desarrollo de necrosis tubular aguda; las lesiones iniciales se observaron a las 3 horas de la inoculación de una dosis de 700 μg del veneno, observándose en corteza renal congestión y degeneración granulohialina de las células epiteliales tubulares, acompa adas de dilatación y cilindros hialinos en la luz tubular. A las 24 horas se presentó necrosis tubular aguda en una superficie extensa de la corteza sin da o de la membrana basal tubular. Las lesiones de degeneración turbia de células epiteliales tubulares, dilatación de la luz tubular y cilindros hialinos se mantuvieron presentes hasta las 4 semanas post-inoculación. Si bien los parámetros de la bioquímica clínica asociados con insuficiencia renal aguda aumentaron a las 6 horas de la administración del veneno (urea: 1.10±0.22 g/dl; creatinina: 19.60±1.51mg/dl), a la semana descendieron a valores normales. Las densidades urinarias, en cambio, a la semana se mantuvieron más bajas que lo normal, 1.005 ± 0.001 (p<0.001) y al mes oscilaron entre 1.005 y 1.060 (p<0.001). El da o renal producido por el veneno de B. neuwiedii diporus pudo ser valorado mejor histopatológicamente que por las técnicas convencionales de laboratorio. Acute renal failure is one of the systemic complications that can be found in bothropic accidents. In this study the effects on male Wistar rats induced by the venom of Bothrops neuwiedii diporus were evaluated. The histopathology revealed acute tubular necrosis, lesions firstly were observed 3 hours post inoculation of 700 μg of venom. Cortical kidney congestion and granulohialin degeneration of tubular epithelial cells were observed, these lesions achieved a maximum at 24 hours after inoculation. Tubular epithelial hidropic degeneration and dilatation of tubular lumen with hyalin casts were present inclusive up to 4 weeks after inoculation. Biochemical parameter values associated with kidney renal failure were increased 6 hours after venom inoculation (urea: 1.10± 0.22 g/dl; creatinine: 19.60±1.51 mg/dl), but at the end of the first week they decreased till normal values. The urinary density was lower than normal value: 1.005±0.001 (p<0.001) and at the end of the first month they oscillated between 1.005 and 1.060 (p<0.001). Renal injury induced by B. neuwiedii diporus could be better apprec
Isolation and biological characterization of a basic phospholipase A2 from Bothrops jararacussu snake venom
Maru?ak,S.L.; Leiva,L; Garcia Denegri,M.E.; Teibler,P; Acosta De Pérez,O;
Biocell , 2007,
Abstract: a phospholipase a2 has been isolated from bothrops jararacussu venom from snakes that inhabit the northeast region of argentina. the present study describes in vivo and in vitro biological activities of phospholipase a2 from b. jararacussu as well as isolation details of its. venom was obtained by milking of adult snakes which were housing in wood reptile cages of varying dimensions in heated (20-30oc) rooms. snakes received a weekly diet of mice and water was available ad libitum for drinking and soaking. the enzyme was purified by gel filtration on a sephadex g-75 column followed by ion exchange chromatography on a sp-sephadex c25 column. the major peak belonging to proteins was retained in the cation exchanger and then eluted using a concentration gradient of kcl that exhibited phospholipase activity. this basic pla2 consists of a single polypeptide chain with a molecular mass of 15.6 kda. it had a high indirect hemolytic activity and produced a significant paw edema reaction in mice. the enzyme showed a low lethality (ld50 148.6 mg) when was administered i.p. but exhibited elevated myotoxic effects in vivo by increasing plasma ck activity of injected mice, corroborated results by the histological observations of samples of gastrocnemius muscle. myonecrosis is the result of intense destruction of muscular fibers that involves local infiltration of inflammatory cells and leads to the highest peak of ck level just after 1 hour mice injection. moreover, the isolated enzyme showed anticoagulant activity, evaluated on sheep platelet-poor plasma which recalcification time was prolonged after incubation with the isolated phospholipase a2. these findings showed that this phospholipase, isolated by only two simple chromatographic steps, possesses high edematogenic and myotoxic activities. however, despite the low lethal activity, this enzyme would contribute markedly to the pathophysiology of the bothropic envenomation.
Isolation and biological characterization of a basic phospholipase A2 from Bothrops jararacussu snake venom  [cached]
S.L. Maru?ak,L Leiva,M.E. Garcia Denegri,P Teibler
Biocell , 2007,
Abstract: A phospholipase A2 has been isolated from Bothrops jararacussu venom from snakes that inhabit the northeast region of Argentina. The present study describes in vivo and in vitro biological activities of phospholipase A2 from B. jararacussu as well as isolation details of its. Venom was obtained by milking of adult snakes which were housing in wood reptile cages of varying dimensions in heated (20-30oC) rooms. Snakes received a weekly diet of mice and water was available ad libitum for drinking and soaking. The enzyme was purified by gel filtration on a Sephadex G-75 column followed by ion exchange chromatography on a SP-Sephadex C25 column. The major peak belonging to proteins was retained in the cation exchanger and then eluted using a concentration gradient of KCl that exhibited phospholipase activity. This basic PLA2 consists of a single polypeptide chain with a molecular mass of 15.6 kDa. It had a high indirect hemolytic activity and produced a significant paw edema reaction in mice. The enzyme showed a low lethality (LD50 148.6 mg) when was administered i.p. but exhibited elevated myotoxic effects in vivo by increasing plasma CK activity of injected mice, corroborated results by the histological observations of samples of gastrocnemius muscle. Myonecrosis is the result of intense destruction of muscular fibers that involves local infiltration of inflammatory cells and leads to the highest peak of CK level just after 1 hour mice injection. Moreover, the isolated enzyme showed anticoagulant activity, evaluated on sheep platelet-poor plasma which recalcification time was prolonged after incubation with the isolated phospholipase A2. These findings showed that this phospholipase, isolated by only two simple chromatographic steps, possesses high edematogenic and myotoxic activities. However, despite the low lethal activity, this enzyme would contribute markedly to the pathophysiology of the bothropic envenomation.
Pulsed ultrasound therapy accelerates the recovery of skeletal muscle damage induced by Bothrops jararacussu venom
Saturnino-Oliveira, J.;Tomaz, M.A.;Fonseca, T.F.;Gaban, G.A.;Monteiro-Machado, M.;Strauch, M.A.;Cons, B.L.;Calil-Elias, S.;Martinez, A.M.B.;Melo, P.A.;
Brazilian Journal of Medical and Biological Research , 2012, DOI: 10.1590/S0100-879X2012007500033
Abstract: we studied the effect of pulsed ultrasound therapy (ust) and antibothropic polyvalent antivenom (pav) on the regeneration of mouse extensor digitorum longus muscle following damage by bothrops jararacussu venom. animals (swiss male and female mice weighing 25.0 ± 5.0 g; 5 animals per group) received a perimuscular injection of venom (1 mg/kg) and treatment with ust was started 1 h later (1 min/day, 3 mhz, 0.3 w/cm2, pulsed mode). three and 28 days after injection, muscles were dissected and processed for light microscopy. the venom caused complete degeneration of muscle fibers. ust alone and combined with pav (1.0 ml/kg) partially protected these fibers, whereas muscles receiving no treatment showed disorganized fascicules and fibers with reduced diameter. treatment with ust and pav decreased the effects of the venom on creatine kinase content and motor activity (approximately 75 and 48%, respectively). sonication of the venom solution immediately before application decreased the in vivo and ex vivo myotoxic activities (approximately 60 and 50%, respectively). the present data show that ust counteracts some effects of b. jararacussu venom, causing structural and functional improvement of the regenerated muscle after venom injury.
Rabbit antivenom efficacy against myotoxic and neurotoxic activities of Bothrops jararacussu venom and bothropstoxin-I
Oshima-Franco, Y.;Leite, G. B.;Valério, A. A.;Hyslop, S.;Andriao-Escarso, S.;Giglio, J. R.;Prado-Franceschi, J.;Cruz-H?fling, M. A.;Rodrigues-Simioni, L.;
Journal of Venomous Animals and Toxins , 2002, DOI: 10.1590/S0104-79302002000200004
Abstract: bothrops jararacussu venom and its major toxin bothropstoxin-i (bthtx-i) possess myotoxic and neurotoxic properties. the efficacy of a rabbit antivenom raised against b. jararacussu venom in the neutralization of physiological, biochemical, and morphological changes induced by the venom and its major toxin bthtx-i was studied in mouse isolated phrenic nerve-diaphragm (pnd) and extensor digitorum longus (edl) preparations. the times required for 50% neuromuscular blockade in pnd and edl preparations for venom were 70+11.5 (s.e.m., n=5) min and 58+8 (n=16) (50 m g/ml), and for bthtx-i 31+6 (n=3) min and 30+3 (n=5) min (20 m g/ml), respectively. after 120 min incubation, creatine kinase (ck) concentrations in solution containing the edl preparations were 3464+346 u/l after exposure to venom (50 m g/ml, n=5) and 3422+135 u/l to bthtx-i (20m g/ml, n=4), respectively. rabbit antivenom dose-dependently neutralized venom and toxin-induced neuromuscular blockade in both preparations and effectively prevented venom and toxin-induced ck release from edl. histological analysis showed that rabbit antivenom neutralized morphological damage caused by b. jararacussu venom and bthtx-i in edl preparations. these results indicate that rabbit antivenom effectively neutralized the biological activities of b. jararacussu venom and bthtx-i.
A eficácia do antiveneno botrópico-crotálico na neutraliza??o das principais atividades do veneno de Bothrops jararacussu
dos-Santos, Maria Cristina;Gon?alves, Luís Roberto de Camargo;Fortes-Dias, Consuelo L.;Cury, Yara;Gutiérrez, José Maria;Furtado, Maria de Fátima D.;
Revista do Instituto de Medicina Tropical de S?o Paulo , 1992, DOI: 10.1590/S0036-46651992000200001
Abstract: myonecrosis is one of the effects of bothrops jararacussu venom, from which a myotoxin was isolated showing structural homology to phospholipase a2 (pla2), but without enzimatic activity. such myotoxic activity is also present in the crotalus durissus terrificus venom, and is atributed to crotoxin and to pla2 (crotoxin b), the basic component of the crotoxin complex. the bothrops jararacussu venom showed three proteins with immunologic identity to pla2 from crotoxin. the bothropic (ab) and the bothropic/crotalic (ab/c) antivenoms, two commercial polyvalent antivenoms produced at instituto butantan, were compared in order to assess their capacity for neutralization of the lethal, hemorrhagic, coagulant and myotoxic activities of bothrops jararacussu venom. both antivenoms showed the same level of hemorrhagic activity neutralization. however, ab/c was about three times more efficient than ab in neutralizing the myotoxic activity, and two times more potent for neutralization of lethality and coagulant activity of bothrops jararacussu venom. these data suggest that the use of ab/c could be of value in the treatment of patients bitten by snakes of this species
Heparin and commercial bothropic antivenom against the paralyzing effect of Bothrops jararacussu snake venom
Rostelato-Ferreira, S;Rodrigues-Simioni, L;Oshima-Franco, Y;
Journal of Venomous Animals and Toxins including Tropical Diseases , 2010, DOI: 10.1590/S1678-91992010005000008
Abstract: the crude venom of bothrops jararacussu (bjssu) is known to induce muscular paralysis in vitro. many studies have shown that various substances, including heparin, neutralize the damage caused by snake venom. in the present study, the ability of heparin (hep) and commercial bothropic antivenom (cba) to neutralize neuromuscular effects of bjssu venom, at different time-points, was analyzed. mouse phrenic nerve-diaphragm preparation was used through a conventional myographic technique, following five different protocols: group 1 was incubated with bjssu (40 μg/ml) without any other treatment; groups 2 and 3 were pretreated with heparin (1 μl/ml) and cba (120 μl/ml), respectively, for 15 minutes before venom addition; group 4 after 50% neuromuscular blockade induced by bjssu crude venom received 1 μl/ml of heparin while group 5 received a mixture of hep:cba:bjssu. control preparations (tyrode) were treated with hep and cba (mean ± sem; n = 3-6). after 120 minutes of venom incubation, group 1 preparations presented twitch-tension of 12 ± 2%. however, in groups 2 and 3, the neutralizations were 92 ± 1.9% and 81 ± 6%, respectively. the heparin addition, after 50% neuromuscular blockade by bjssu, produced 40 ± 6% muscular response after 120 minutes of incubation. hep:cba:bjssu mixture displayed a protective effect of 84 ± 10% against venom action. in conclusion, heparin and commercial bothropic antivenom efficiently neutralized the neurotoxic effects caused by b. jararacussu crude venom, even at different incubation time-points.
Histological and biochemical effects induced by sublethal doses of Bothrops jararacussu venom in mice
Zeni, A. L. B.;Becker, A.;Krug, M.;Albuquerque, C. A. C.;
Journal of Venomous Animals and Toxins including Tropical Diseases , 2007, DOI: 10.1590/S1678-91992007000300009
Abstract: snake venom is characterized by hemorrhagic, coagulant, proteolytic and myotoxic activities which in bothrops jaracussu venom are related to intraspecific variations. in the present study, female swiss mice were divided into two groups: treated with 25μg or 50μg venom. these were subdivided into three groups of six animals each, according to blood collection: 2, 4 or 24h after venom injection. animals were anesthetized using diethyl-ether inhalation and 1ml of blood was collected by heart puncture. then, the following organs were removed: spleen, skeletal muscle, kidneys, liver and lungs; histological sections were obtained and stained with hematoxylin-eosin (he). the following biochemical parameters were analyzed: aspartate aminotransferase (ast/got), alanine aminotransferase (alt/gpt), total lactate dehydrogenase (ldh), glucose, creatinine and urea levels, and total protein content. results showed significant alterations in ast, ldh, glucose and urea levels, and total protein content, as well as important tissue alterations in the liver, kidneys and lungs. it could be concluded that, even using sublethal doses of venom, there were significant changes in almost all the tested biochemical parameters as well as tissue alterations in the kidneys and lungs.
Low-level laser therapy decreases local effects induced by myotoxins isolated from Bothrops jararacussu snake venom
Barbosa, AM;Villaverde, AB;Guimar?es-Sousa, L;Soares, AM;Zamuner, SF;Cogo, JC;Zamuner, SR;
Journal of Venomous Animals and Toxins including Tropical Diseases , 2010, DOI: 10.1590/S1678-91992010000300014
Abstract: the prominent myotoxic effects induced by bothrops jararacussu crude venom are due, in part, to its polycationic myotoxins, bthtx-i and bthtx-ii. both myotoxins have a phospholipase a2 structure: bthtx-ii is an active enzyme asp-49 pla2, while bthtx-i is a lys-49 pla2 devoid of enzymatic activity. in this study, the effect of low-level laser therapy (lllt), 685 nm laser at a dose of 4.2 j/cm2 on edema formation, leukocyte influx and myonecrosis caused by bthtx-i and bthtx-ii, isolated from bothrops jararacussu snake venom, was analyzed. bthtx-i and bthtx-ii caused a significant edema formation, a prominent leukocyte infiltrate composed predominantly by neutrophils and myonecrosis in envenomed gastrocnemius muscle. lllt significantly reduced the edema formation, neutrophil accumulation and myonecrosis induced by both myotoxins 24 hours after the injection. lllt reduced the myonecrosis caused by bthtx-i and bthtx-ii, respectively, by 60 and 43%; the edema formation, by 41 and 60.7%; and the leukocyte influx, by 57.5 and 51.6%. in conclusion, lllt significantly reduced the effect of these snake toxins on the inflammatory response and myonecrosis. these results suggest that lllt should be considered a potential therapeutic approach for treatment of local effects of bothrops species venom.
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