title: Vellozia flavicans Mart. ex Schult. hydroalcoholic extract inhibits the neuromuscular blockade induced by Bothrops jararacussu venom.
abstract: BACKGROUND
  Snakebite is a significant public health issue in tropical countries. In Brazil, some of the most common snake envenomations are from Bothrops. Bothrops bites trigger local and systemic effects including edema, pain, erythema, cyanosis, infections, and necrosis. Vellozia flavicans is a plant from the Brazilian "cerrado" (savanna) that is popularly used as an anti-inflammatory medicine. Since inflammation develops quickly after Bothrops bites, which can lead to infection, the aim of the present study was to observe possible anti-snake venom and antimicrobial activities of V. flavicans (Vf).
  
  
  METHODS
  The chromatographic profile of the main constituents from the Vf leaf hydroalcoholic extract was obtained by thin-layer chromatography (TLC). The anti-snake venom activity was measured by Vf's ability to neutralize the in vitro neuromuscular blockade caused by Bothrops jararacussu venom (Bjssu) in a mouse phrenic nerve-diaphragm model (PND). After a 20 min incubation, preparations of PND were added to Tyrode's solution (control); Vf (0.2, 0.5, 1, and 2 mg/mL); 40 μg/mL Bjssu; pre-incubation for 30 min with Bjssu and 1 mg/mL Vf; and a Bjssu pretreated preparation (for 10 min) followed by 1 mg/mL Vf. Myographic recording was performed, and the contractile responses were recorded. The antimicrobial activity (minimum inhibitory concentration [MIC] and minimum bactericidal concentration [MBC]) was obtained for Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Enterococcus faecalis, using gentamicin and vancomycin as positive controls.
  
  
  RESULTS
  TLC analysis yielded several compounds from Vf, such as flavonoids (quercetin) and phenolic acids (chlorogenic acid). Bjssu completely blocked the contractile responses of PND preparations, while Vf preserved 97% (±10%) of the contractile responses when incubated with Bjssu. In the PND pretreated with Bjssu, Vf was able to inhibit the neuromuscular blockade progress. MIC and MBC of Vf ranged from 2.5 to 5.0 mg/mL for P. aeruginosa and S. aureus strains, while no antimicrobial activity was observed for E. coli and E. faecalis.
  
  
  CONCLUSIONS
  The hydroalcoholic extract from Vf leaves was able to neutralize and decrease the in vitro neuromuscular blockade caused by Bjssu. However, it did not show significant antimicrobial activity against the tested bacteria.
authors: Natália
authors: N
authors: Tribuiani
authors: Alexandro Mateus
authors: AM
authors: da Silva
authors: Miriéle Cristina
authors: MC
authors: Ferraz
authors: Magali Glauzer
authors: MG
authors: Silva
authors: Ana Paula Guerreiro
authors: AP
authors: Bentes
authors: Talita Signoreti
authors: TS
authors: Graziano
authors: Marcio Galdino
authors: MG
authors: dos Santos
authors: José Carlos
authors: JC
authors: Cogo
authors: Pharmaceutical Sciences Faculty of Araraquara, São Paulo State University (UNESP), Rodovia Araraquara-Jau, Km 1, Araraquara, São Paulo CEP 14801-902, Brazil. varandae@fcfar.unesp.br.
authors: Eliana Aparecida
authors: EA
authors: Varanda
authors: Francisco Carlos
authors: FC
authors: Groppo
authors: Karina
authors: K
authors: Cogo
authors: Yoko
authors: Y
authors: Oshima-Franco
mesh_terms: D000818:Animals; D000997:Antivenins / Q000494:pharmacology / Q000627:therapeutic use*; D017837:Bothrops; D001938:Brazil; D002855:Chromatography, Thin Layer; D003435:Crotalid Venoms / Q000037:antagonists & inhibitors* / Q000633:toxicity; D003964:Diaphragm / Q000187:drug effects; D019684:Magnoliopsida; D008297:Male; D051379:Mice; D009119:Muscle Contraction / Q000187:drug effects*; D019148:Neuromuscular Blockade; D010243:Paralysis / Q000139:chemically induced / Q000517:prevention & control; D010791:Phrenic Nerve / Q000187:drug effects; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use; D018515:Plant Leaves; D012909:Snake Bites / Q000188:drug therapy* / Q000503:physiopathology
chemical_list: D000997:Antivenins; D003435:Crotalid Venoms; D010936:Plant Extracts