title: Plants used to treat snakebites in Santarém, western Pará, Brazil: an assessment of their effectiveness in inhibiting hemorrhagic activity induced by Bothrops jararaca venom.
abstract: BACKGROUND
  The poor distribution and limited availability of antivenoms in Brazil have led to greater use of plants to treat snakebites. Very often such plants are the only alternative available to riverside communities.
  
  
  METHODS
  Direct questionnaire-based interviews were conducted with members of the Cucurunã, São Pedro and Alter do Chão communities in Santarém, Pará, Brazil. For each of the 12 most frequently mentioned species aqueous extracts were prepared and the phytochemical profiles determined by thin layer chromatography. The concentrations of phenolic compounds (tannins and flavonoids) in the aqueous extracts were determined by colorimetric assays. To assess inhibition of the hemorrhagic activity of Bothrops jararaca venom, solutions containing the venom mixed with aqueous extracts in the ratios 1:12 and 1:48 were tested (w/w). SDS-PAGE and Western blot were used to assess the action of the extracts on Bothrops jararaca venom.
  
  
  RESULTS
  In all, 24 plants belonging to 19 families were mentioned in the survey as being used to treat snakebites. Leaves (84%), seeds (60.9%) and inner bark (53%) were cited as the most frequently used parts in folk remedies, which were usually prepared in the form of a decoction (62.5%), tincture (45%) or maceration (22.5%). Hemorrhage induced by Bothrops jararaca venom was completely inhibited by aqueous extracts of Bellucia dichotoma, Connarus favosus, Plathymenia reticulata and Philodendron megalophyllum, which had a high phenolic content and contained condensed and hydrolyzable tannins. The results of SDS-PAGE showed that some venom protein bands were not visible when the venom was preincubated with the extracts that had completely inhibited hemorrhagic activity of the venom. Western blot showed that the extracts did not have any enzymatic action on the proteins in the venom as it failed to detect low-molecular-weight bands, which are indicative of possible enzymatic cleavage.
  
  
  CONCLUSIONS
  Traditional use of plants to treat snakebites is a common practice in the western region of Pará, Brazil. Our findings show that some plant extracts were able to inhibit snake venom-induced hemorrhage in vitro. In vivo studies are being carried out to validate the traditional use of these species to treat snakebites.
authors.affiliation: Programa de Pós-Graduação em Recursos Naturais da Amazônia, Laboratório de Bioprospecção e Biologia Experimental, Universidade Federal do Oeste do Pará - UFOPA, Rua Vera Paz, s/n, 68035-110 Santarém, PA, Brazil; Programa Multi-Institucional de Pós-Graduação em Biotecnologia, Laboratório de Imunologia, Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal do Amazonas - UFAM, Av. Rodrigo Octávio Ramos, 3000 Manaus, AM, Brazil. Electronic address: mouraovm@yahoo.com.br.
authors.forename: Valéria Mourão
authors.initials: VM
authors.lastname: de Moura
authors.affiliation: Programa de Pós-Graduação em Recursos Naturais da Amazônia, Laboratório de Bioprospecção e Biologia Experimental, Universidade Federal do Oeste do Pará - UFOPA, Rua Vera Paz, s/n, 68035-110 Santarém, PA, Brazil.
authors.forename: Luciana A
authors.initials: LA
authors.lastname: Freitas de Sousa
authors.affiliation: Programa Multi-Institucional de Pós-Graduação em Biotecnologia, Laboratório de Imunologia, Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal do Amazonas - UFAM, Av. Rodrigo Octávio Ramos, 3000 Manaus, AM, Brazil.
authors.forename: Maria
authors.initials: M
authors.lastname: Cristina Dos-Santos
authors.affiliation: Programa de Pós-Graduação em Recursos Naturais da Amazônia, Laboratório de Bioprospecção e Biologia Experimental, Universidade Federal do Oeste do Pará - UFOPA, Rua Vera Paz, s/n, 68035-110 Santarém, PA, Brazil.
authors.forename: Juliana Divina
authors.initials: JD
authors.lastname: Almeida Raposo
authors.affiliation: Programa de Pós-Graduação em Recursos Naturais da Amazônia, Laboratório de Bioprospecção e Biologia Experimental, Universidade Federal do Oeste do Pará - UFOPA, Rua Vera Paz, s/n, 68035-110 Santarém, PA, Brazil.
authors.forename: Aline
authors.initials: A
authors.lastname: Evangelista Lima
authors.affiliation: Programa de Pós-Graduação em Recursos Naturais da Amazônia, Laboratório de Bioprospecção e Biologia Experimental, Universidade Federal do Oeste do Pará - UFOPA, Rua Vera Paz, s/n, 68035-110 Santarém, PA, Brazil.
authors.forename: Ricardo Bezerra
authors.initials: RB
authors.lastname: de Oliveira
authors.affiliation: Programa de Pós-Graduação em Química, Universidade Federal do Pará - UFPA, Rua Augusto Corrêa, 66075-110 Belém, PA, Brazil.
authors.forename: Milton Nascimento
authors.initials: MN
authors.lastname: da Silva
authors.affiliation: Programa de Pós-Graduação em Recursos Naturais da Amazônia, Laboratório de Bioprospecção e Biologia Experimental, Universidade Federal do Oeste do Pará - UFOPA, Rua Vera Paz, s/n, 68035-110 Santarém, PA, Brazil.
authors.forename: Rosa Helena
authors.initials: RH
authors.lastname: Veras Mourão
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D000997:Antivenins / Q000627:therapeutic use*; D017837:Bothrops; D001938:Brazil; D003435:Crotalid Venoms / Q000037:antagonists & inhibitors*; D005260:Female; D006470:Hemorrhage / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008519:Medicine, Traditional; D051379:Mice; D008875:Middle Aged; D064209:Phytochemicals / Q000032:analysis; D008517:Phytotherapy; D010936:Plant Extracts / Q000737:chemistry / Q000627:therapeutic use*; D010946:Plants, Medicinal; D012909:Snake Bites / Q000188:drug therapy*
chemical_list: D000997:Antivenins; D003435:Crotalid Venoms; D064209:Phytochemicals; D010936:Plant Extracts
keywords: Anti-snakebite plants; Ethnobotany; Hemorrhage; Plant extracts; Snakebite envenomation