Effects of jararhagin, a haemorrhagic metalloproteinase from Bothrops jararaca venom, on platelet and plasma proteins involved in haemostasis

SIGLEAvailable from British Library Document Supply Centre- DSC:DX186622 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Snake venom metalloproteinases and disintegrins: interactions with cells

Metalloproteinases and disintegrins are important components of most viperid and crotalid venoms. Large metalloproteinases referred to as MDC enzymes are composed of an N-terminal Metalloproteinase domain, a Disintegrin-like domain and a Cys-rich C-terminus. In contrast, disintegrins are small non-enzymatic RGD-containing cysteine-rich polypeptides. However, the disintegrin region of MDC enzymes bears a high degree of structural homology to that of the disintegrins, although it lacks the RGD motif. Despite these differences, both components share the property of being able to recognize integrin cell surface receptors and thereby to inhibit integrin-dependent cell reactions. Recently, several membrane-bound MDC enzymes, closely related to soluble venom MDC enzymes, have been described in mammalian cells. This group of membrane-anchored mammalian enzymes is also called the ADAM family of proteins due to the structure revealing A Disintegrin And Metalloproteinase domains. ADAMs are involved in the shedding of molecules from the cell surface, a property which is also shared by some venom MDC enzymes

Lance-headed viper (Bothrops moojeni) bite wounding the eye Acidente botrópico (Bothrops moojeni) com ferimento ocular

A 5-year-old girl was bitten in her left eye by a lance-headed viper identified as Bothrops moojeni, measuring 115 cm of length. There was severe facial swelling and left exophthalmus, and enucleation of the eye was necessary. The patient apparently had mild systemic envenoming, but local inflammatory signs and histological evidence of necrosis suggest that both the mechanical trauma and the local action of the venom had a role in the genesis of the eye lesion. It is arguable if the loss of the eye could be prevented even if the antivenom was administered earlier.<br>Uma menina de 5 anos de idade foi picada no olho esquerdo por uma serpente da espécie Bothrops moojeni, que media 115 cm de comprimento. Houve intenso edema facial e ex-oftalmia; enucleação do olho foi necessária. A paciente aparentemente apresentou um envenenamento sistêmico leve, mas os sinais inflamatórios locais e a evidência histológica de necrose sugerem que tanto o traumatismo mecânico como a ação local do veneno tiveram um papel na gênese da lesão ocular. É questionável se o prognóstico da lesão ocular teria sido diferente se o antiveneno tivesse sido administrado em dose adequada mais precocemente

Treatment of Bothrops alternatus envenomation by Curcuma longa and Calendula officinalis extracts and ar-turmerone Tratamento local do envenenamento por Bothrops alternatus com extrato de Curcuma longa e Calendula officinalis e ar-turmerone

It was investigated the efficiency of two extracts of plants and one fraction of their properties against the local effects of bothropic envenomation. Bothrops alternatus venom (1.25µg) diluted in 100µl of sterile saline solution was inoculated (intradermally) into the shaved dorsal back skin of 30 New Zealand rabbits. The animals were divided in six groups receiving the following treatments: group I: subcutaneous application of Curcuma longa extract (1.0ml); group II: topic treatment of Curcuma longa hydroalcoholic extract (1.0ml); group III: topic application of ar-turmerone in vaseline (1.0g); group IV: topic application of Curcuma longa methanolic extract (1.0ml); group V: topic application of Calendula officinalis ointment (1.0g); group VI: topic application of saline (1.0ml). These treatments were done at 30 minutes, and at 2, 4, 24 and 72 hours after venom inoculation. Intensity of local edema, hemorrhagic halo and necrosis were evaluated until 168h after that. Additionally, seven days after the Bothrops venom inoculation, blood was collected from heart with and without EDTA (10%) for hemogram and biochemical parameters (total protein, blood urea nitrogen, creatinine, and fibrinogen) and all the animals were anesthetized, sacrificed by ether inhalation and submitted to necropsy. Fragments of tissues were taken for histopathological evaluation. The most efficient treatment for inhibition of edema, necrosis and local hemorrhage after Bothrops alternatus venom was the topic application of ar-turmerone.<br>Investigou-se a eficácia do extrato de plantas no tratamento local do envenenamento botrópico. Veneno de serpentes Bothrops alternatus (1,25µg) diluído em 100µl de solução salina estéril foi inoculado (via intradérmica) entre as escápulas de 30 coelhos. Os animais foram divididos em seis grupos (tratamentos): grupo I: tratamento subcutâneo com extrato de Curcuma longa; grupo II: tratamento tópico com extrato hidroalcoólico de Curcuma longa; grupo III: tratamento tópico com ar-turmerone em vaselina; grupo IV: tratamento tópico com extrato metanólico de Curcuma longa; grupo V: tratamento tópico com pomada de Calendula officinalis e grupo VI: aplicação tópica de solução salina a 0,9% (Controle). Os tratamentos foram realizados 30 minutos, 2h, 4h, 24h e 72h após a inoculação do veneno. Foram avaliados intensidade de edema local (com paquímetro), halo hemorrágico (régua com gabaritos circulares) e presença de necrose. Sete dias após a inoculação do veneno botrópico (168h) foi coletado sangue do coração, com e sem EDTA, para realização de hemograma, dosagem plasmática de fibrinogênio e dosagens séricas de proteína total, uréia e creatinina. Após as coletas de sangue, todos os animais foram anestesiados, sacrificados com inalação pelo éter etílico e necropsiados. Fragmentos de pele foram retirados para avaliação histopatológica. Os resultados obtidos mostraram que o tratamento mais eficaz para inibição da evolução do edema, necrose e hemorragia local após envenenamento com Bothrops alternatus foi a aplicação tópica de ar-turmerone