Pimenta pseudocaryophyllus inhibits virulence factors and promotes metabolic changes in Candidayeast

• Autor(a) principal: Assal,Flávio Ezeddinne El
• Data de Publicação: 2014
• Outros Autores: Paula,Joelma Abadia Marciano, Capeletti,Leonardo Silva, Abrão,Fernando Yano, Ataídes,Fábio Silvestre, Sá,Fabyola Amaral da Silva, Costa,Carolina Rodrigues, Fernandes,Orionalda de Fátima Lisboa, Souza,Lúcia Kioko Hasimoto, Silva,Maria do Rosario Rodrigues
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Revista da Sociedade Brasileira de Medicina Tropical
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0037-86822014000500618
• topic: Pimenta pseudocaryophyllus; Candida spp; Antifungal activity; Virulence factors; Metabolic changes

IntroductionThis is the first study to examine the in vitrosusceptibility and the expression of virulence factors in Candida species in the presence of Pimenta pseudocaryophyllus (Gomes) L.R. Landrum (Myrtaceae), a Brazilian plant known as paucravo. Additionally, the mechanisms of action of the crude ethanol extract and the ethyl acetate and aqueous fractions of this plant were investigated.MethodsThe in vitro susceptibility of Candida was tested using the broth microdilution method, whereas an XTT reduction assay was used for biofilms. Adherence was determined by counting the number of yeast cells that adhered to 100 oral epithelial cells, and hyphal formation was verified in the hyphal induction medium M199. Flow cytometry with propidium iodide and FUN-1 was performed to assess the mechanism of action.ResultsThe results revealed that the crude ethanol extract and the ethyl acetate and aqueous fractions of P. pseudocaryophyllusinhibited the growth of Candida isolates at a minimal inhibitory concentration (MIC) ranging from 64 to 256µg/mL, whereas the 50% sessile minimal inhibitory concentration (SMIC50) ranged from 512 to >1,024µg/mL. Adherence and hyphal formation were significantly reduced in the presence of the crude ethanol extract and both fractions. Although cell membrane injury was detected, the predominant mechanism of action appeared to be the alteration of yeast metabolism, as demonstrated by flow cytometry.ConclusionsOur results indicated that antifungal activity reduced the expression of virulence factors in yeast via the alteration of yeast metabolism, suggesting that the crude extract of P. pseudocaryophyllus and its fractions may contain novel antifungal agents.