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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.
Acción del veneno de Bothrops jararacussu de Argentina sobre la coagulación sanguínea Activity of the venom of Bothrops jararacussu of Argentina on blood coagulation  [cached]
S.L. Maru?ak,R.M. Ruíz de Torrent,G.P. Teibler,C.C. Gay
InVet , 2006,
Abstract: La intoxicación por mordeduras de serpientes del género Bothrops (yarará) de Argentina se caracteriza por causar efectos locales y sistémicos. Entre los sistémicos pueden generar alteraciones en la coagulación de la sangre, hemorragias, shock, insuficiencia renal. En este trabajo se estudiaron los efectos que causa el veneno de Bothrops jararacussu de Misiones, Argentina, sobre la coagulación de la sangre. Se utilizaron métodos in vitro e in vivo para evaluar la actividad coagulante, fibrinolítica y defibrinante, como así también la capacidad de degradar el fibrinógeno y la letalidad del veneno. El veneno mostró ser α-fibrinogenolítico y los resultados para las actividades ensayadas fueron: concentración coagulante mínima (CCM) 18,5 μg/ml, concentración fibrinolítica mínima (CFM) 9,5 mg/ml, dosis defibrinante mínima (DDM) 1,56 μg, DL50 43,52 μg/ratón, los que difieren de los obtenidos para otras especies de Bothrops e incluso dentro de la misma especie, pero distribuídas en otras regiones sudamericanas. Se concluye que el veneno de B. jararacussu de Argentina afecta marcadamente el sistema hemostático, y que las actividades coagulantes y anticoagulantes exhibidas por esta secreción probablemente influyan en la letalidad del veneno, dado que contribuirían a la aparición de hemorragias que, de ser severas, conducen a fallo renal y muerte de la víctima. 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 promo
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.
Bothrops jararacussu venom-induced neuromuscular blockade inhibited by Casearia gossypiosperma Briquet hydroalcoholic extract
Camargo, TM;Nazato, VS;Silva, MG;Cogo, JC;Groppo, FC;Oshima-Franco, Y;
Journal of Venomous Animals and Toxins including Tropical Diseases , 2010, DOI: 10.1590/S1678-91992010000300009
Abstract: the hydroalcoholic extract of casearia gossypiosperma briquet (flacourtiaceae) was standardized for the first time through quality control procedures including pharmacognostic methods, fingerprint chromatograms, defined amounts of marker substances and physicochemical characteristics. the pharmacological activity of c. gossypiosperma (cg) hydroalcoholic extract was assayed by a traditional in vitro test, which involved irreversible neuromuscular blockade induced by bothrops jararacussu (bjssu) venom (60 μg/ml) in mouse phrenic nerve-diaphragm preparations. bjssu venom blocked muscle activity for 26 (± 2.0) minutes (n = 6). cg extract (0.1 mg/ml) induced changes on the baseline muscle activity without impairing the muscle function and inhibited 87.6% (± 1.8) (n = 6) of the bjssu venom-induced blockade. both flavonoids (0.624 g%) and polyphenols (4.63 g%) from the extract were spectrophotometrically quantified. therefore, the present study confirms the antibothropic activity of cg extract, supporting the ethnomedical use of casearia sp. in the treatment of snakebite victims.
Neutralization of pharmacological and toxic activities of Bothrops jararacussu snake venom and isolated myotoxins by Serjania erecta methanolic extract and its fractions
Fernandes, RS;Costa, TR;Marcussi, S;Bernardes, CP;Menaldo, DL;Rodriguéz Gonzaléz, II;Pereira, PS;Soares, AM;
Journal of Venomous Animals and Toxins including Tropical Diseases , 2011, DOI: 10.1590/S1678-91992011000100011
Abstract: most of the snakebites recorded in brazil are caused by the bothrops genus. given that the local tissue damage caused by this genus cannot be treated by antivenom therapy, numerous studies are focusing on supplementary alternatives, such as the use of medicinal plants. serjania erecta has already demonstrated anti-inflammatory, antiseptic and healing properties. in the current study, the aerial parts of s. erecta were extracted with methanol, then submitted to chromatographic fractionation on a sephadex lh20 column and eluted with methanol, which resulted in four main fractions. the crude extract and fractions neutralized the toxic activities of bothrops jararacussu snake venom and isolated myotoxins (bthtx-i and ii). results showed that phospholipase a2, fibrinogenolytic, myotoxic and hemorrhagic activities were inhibited by the extract. moreover, the myotoxic and edematous activities induced by bthtx-i, and phospholipase a2 activity induced by bthtx-ii, were inhibited by the extract of s. erecta and its fraction. the clotting time on bovine plasma was significantly prolonged by the inhibitory action of fractions sf3 and sf4. this extract is a promising source of natural inhibitors, such as flavonoids and tannins, which act by forming complexes with metal ions and proteins, inhibiting the action of serineproteases, metalloproteases and phospholipases a2.
Anti-inflammatory activity of Blutaparon portulacoides ethanolic extract against the inflammatory reaction induced by Bothrops jararacussu venom and isolated myotoxins BthTX-I and II
Pereira, IC;Barbosa, AM;Salvador, MJ;Soares, AM;Ribeiro, W;Cogo, JC;Zamuner, SR;
Journal of Venomous Animals and Toxins including Tropical Diseases , 2009, DOI: 10.1590/S1678-91992009000300013
Abstract: this article reports the anti-inflammatory effect of blutaparon portulacoides (b. portulacoides), specifically the ethanolic extract of its aerial parts, on the edema formation and leukocyte influx caused by bothrops jararacussu (b. jararacussu) snake venom and bothropstoxin-i and ii (bthtx-i and ii) isolated from this venom as an alternative treatment for bothrops snakebites. the anti-inflammatory effect of b. portulacoides ethanolic extract was compared with an animal group pretreated with dexamethasone. b. portulacoides ethanolic extract significantly inhibited paw edema induced by b. jararacussu venom and by bthtx-i and ii. also, results demonstrated that the extract caused a reduction of the leukocyte influx induced by bthtx-i. however, the extract was not capable of inhibiting the leukocyte influx induced by the venom and by bthtx-ii. in conclusion, these results suggest that the ethanolic extract of this plant possess components able to inhibit or inactivate toxins present in b. jararacussu venom, including its myotoxins, responsible for the edema formation. however, the leukocyte migration caused by the venom and bthtx-ii was not inhibited by the plant, probably due to the different mechanisms involved in the edema formation and leukocyte influx. this is the first report of b. portulacoides extract as anti-inflammatory against snake venoms and isolated toxins.
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.
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