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1.
Toxicon ; 220: 106941, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36240857

RESUMO

Bothrops snake envenomation is characterized by severe local manifestations such as pain, edema, inflammation, hemorrhage, and myonecrosis. Furthermore, it is described that venom from juvenile and adult snakes may have differences in their composition that can lead to differences in the evolution of the clinical manifestation of the victim. Photobiomodulation (PBM) has been shown to be an effective adjuvant therapy to serum therapy to reduce the local effects induced by bothropic snake venom. This study evaluated the effect of PBM on the local reaction, after Bothrops alternatus snake venom (BaV) injection, in its juvenile (BaJV) and adult (BaAV) stages. Balb/C mice were injected with the juvenile or adult venoms of BaV or saline solution (control group). PBM at a wavelength of 660 nm, 100 mW, 0.33 W/cm2, 40 s, and a 0.028 cm2 beam was applied transcutaneous to a single point with a radiant exposure of 4 J/cm2, 30 min after venom injection. Edema, inflammatory infiltrate, hyperalgesia, and myonecrosis were analyzed. Both venoms induced significant edema and myonecrosis in the gastrocnemius muscle. Hyperalgesia in the mice paw and a prominent leukocyte infiltrate into the peritoneum were also observed. PBM significantly reduced all evaluated parameters. In conclusion, PBM treatment was effective in reducing the local effects induced by B. alternatus venom at different stages of snake development and could be a useful tool as an adjuvant treatment for bothropic envenomation.


Assuntos
Bothrops , Venenos de Crotalídeos , Terapia com Luz de Baixa Intensidade , Doenças Musculares , Camundongos , Animais , Venenos de Crotalídeos/toxicidade , Hiperalgesia , Venenos de Serpentes/toxicidade , Edema/induzido quimicamente , Edema/radioterapia
2.
Int J Biol Macromol ; 141: 1044-1054, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31494155

RESUMO

A new weak hemorrhagic metalloproteinase named BtaMP-1 was purified from Bothriopsis taeniata snake venom by molecular exclusion followed by anion exchange chromatographies. This protein showed a molecular mass of 25,968.16 Da and is composed of 218 amino acid residues. The multiple alignments of its partial amino acid sequence showed high structural identity with other P-I class SVMP. BtaMP-1 showed caseinolytic activity that was enhanced by Ca2+ ion, completely inhibited by chelating and reducing agents and can be classified as an α-fibrinogenolytic enzyme. Locally, BtaMP-1 induces hemorrhage and edema, but not myotoxicity. These findings were confirmed by histological analysis of mouse gastrocnemius muscle. "In vitro" studies suggest that BtaMP-1 induce cytotoxicity in myoblast C2C12 but not in the myotubes cell line. BtaMP-1 induced systemic alterations in mice with one MHD and two hours exposure; histological analysis of lungs showed hemorrhagic areas, congestion, and increase the thickness of alveolar septum. Also, this protein induced mild effects on kidney and disruption of coagulation by depletion of fibrinogen plasma levels. This work provides insights into the importance of BtaMP-1 biological effects in envenomation by Bothropsis taeniata snake venom and providing further evidence to understand the role of P-I class SVMP in ophidian envenomation.


Assuntos
Bothrops , Venenos de Crotalídeos/enzimologia , Metaloendopeptidases/toxicidade , Sequência de Aminoácidos , Animais , Coagulação Sanguínea/efeitos dos fármacos , Linhagem Celular , Masculino , Metaloendopeptidases/química , Camundongos
3.
Curr Top Med Chem ; 19(22): 1962-1980, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31345151

RESUMO

Among the ophidians that inhabit the Northeast of Argentina, the genus Bothrops such as B. alternatus and B. diporus species (also known as yararás) and Crotalus durisus terrificus (named cascabel), represent the most studied snake venom for more than thirty years. These two genera of venomous snakes account for the majority of poisonous snake envenomations and therefore, constitute a medical emergency in this region. This review presents a broad description of the compiled knowledge about venomous snakebite: its pathophysiological action, protein composition, isolated toxins, toxin synergism, toxin-antitoxin cross-reaction assays. Properties of some isolated toxins support a potential pharmacological application.


Assuntos
Venenos de Serpentes/farmacologia , Toxinas Biológicas/farmacologia , Animais , Argentina , Bothrops , Crotalus , Humanos , Venenos de Serpentes/química , Venenos de Serpentes/isolamento & purificação , Toxinas Biológicas/química , Toxinas Biológicas/isolamento & purificação
4.
Food Chem ; 269: 610-617, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30100479

RESUMO

Acid proteases from sábalo stomach mucosa were recovered using salting-out procedure. This single step produced an enzyme extract purified 1.8-fold over the crude extract with a recovery of 45.1% of its initial proteolytic activity. Sábalo proteases exhibited the highest activity at 45 °C-pH 2.0, showed pH stability between 2.0 and 5.0 and retained more than 70% of its activity after incubation at pH 7.0 for 2 h. Fish extract was unstable at temperatures greater than 45 °C. Its activity was inhibited by pepstatin A but not by PMSF, while EDTA and SDS showed partial inhibitory effects. Presence of CaCl2 and MgCl2 increased the proteolytic activity, while increasing concentrations of NaCl strongly decreased it. In addition, compared to the acid extraction method, the use of sábalo enzymatic extract increased 1.7 times the yield of collagen extraction.


Assuntos
Caraciformes/metabolismo , Colágeno/química , Digestão , Peptídeo Hidrolases/metabolismo , Animais
6.
Acta toxicol. argent ; 9(1): 9-12, jul. 2001. ilus
Artigo em Espanhol | LILACS | ID: lil-356470

RESUMO

Se estudió la actividad proteolítica de los venenos del género Bothrops de diferentes especies que habitan el litoral argentino y su neutralización por un suero hiperinmune bivalente producido en la Argentina. Se midió la actividad proteolíticas sobre caseína y se determinó la dosis proteolítica mínima (DPM), y la dosis efectiva 50 (DE) del suero bivalente frente a cada veneno. Las actividades proteolíticas de los venenos B, alternatus, B. neuwiedii, B. jararaca, B. jararacussu y B. moojeni fueron inferiores a las que presentan otras especies de Bothrops que habitan la región de America Central. Los resultados de la DE mostraron que el suero fue efectivo para neutralizar tal actividad en todos ellos, a pesar de que el suero utilizado en estas experiencias era específico para B. alternatus y B. neuwiedii.


Assuntos
Antivenenos , Bothrops lanceolatus , Venenos de Víboras/efeitos adversos , Venenos de Víboras/toxicidade
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