title: Biological activity of the azlactone derivative EPA-35 against Trypanosoma cruzi.
abstract: Chagas disease, caused by Trypanosoma cruzi, affects six to seven million people worldwide. Treatment is based on benznidazole, producing several side effects and debatable efficacy, highlighting the need for new alternative drugs. We investigated the activity of four C-4 functionalized azlactone derivatives (EPA-27, EPA-35, EPA-63 and EPA-91) as potential T. cruzi inhibitors. Screening with epimastigotes indicated EPA-35 as the best compound (IC50/24 h: 33 μM). This compound was 14.1 times more potent against intracellular amastigotes (IC50/24 h: 2.34 μM). Treatment of infected Vero cells for 72 h (up to 30 μM EPA-35) resulted in a dose-dependent decrease in number of trypomastigotes and amastigotes released in the supernatant, but the amastigote/trypomastigote ratio remained constant, indicating that amastigote growth was disturbed, but cell differentiation was unaffected. Analysis of treated epimastigotes by flow cytometry indicated that the plasma membrane remained intact, but there was a significant decrease in mitochondrial membrane potential. The pattern of cell distribution in the cell cycle stages (G1, G2, M) was unaltered in treated epimastigotes, indicating a trypanocidal rather than a trypanostatic activity. Scanning electron microscopy and flow cytometry showed epimastigotes with a round shape and decrease in cell size. Taken together, our data indicate that the EPA-35 is effective against T. cruzi. Synthetic transformation of EPA-35 into other derivatives may provide promising compounds for further evaluation against this parasite.
authors.affiliation: Laboratory of Cell Biology, Carlos Chagas Institute/Fiocruz-PR, 81350-010 Curitiba-PR, Brazil.
authors.forename: Camila Maria Oliveira
authors.initials: CM
authors.lastname: de Azeredo
authors.affiliation: Department of Chemistry, Federal University of Juiz de Fora, 36036-900 Juiz de Fora, MG, Brazil.
authors.forename: Eloah Pereira
authors.initials: EP
authors.lastname: Ávila
authors.affiliation: Department of Chemistry, Federal University of Juiz de Fora, 36036-900 Juiz de Fora, MG, Brazil.
authors.forename: Danielle Lobo Justo
authors.initials: DL
authors.lastname: Pinheiro
authors.affiliation: Department of Chemistry, Federal University of Juiz de Fora, 36036-900 Juiz de Fora, MG, Brazil.
authors.forename: Giovanni Wilson
authors.initials: GW
authors.lastname: Amarante
authors.affiliation: Laboratory of Cell Biology, Carlos Chagas Institute/Fiocruz-PR, 81350-010 Curitiba-PR, Brazil.
authors.forename: Maurilio José
authors.initials: MJ
authors.lastname: Soares
mesh_terms: D000818:Animals; D002453:Cell Cycle / Q000187:drug effects; D002522:Chlorocebus aethiops; D055808:Drug Discovery; D020128:Inhibitory Concentration 50; D007783:Lactones / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D008018:Life Cycle Stages / Q000187:drug effects; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008855:Microscopy, Electron, Scanning; D009593:Nitroimidazoles / Q000627:therapeutic use; D014344:Trypanocidal Agents / Q000494:pharmacology*; D014349:Trypanosoma cruzi / Q000187:drug effects* / Q000254:growth & development / Q000648:ultrastructure; D014709:Vero Cells
chemical_list: D007783:Lactones; D009593:Nitroimidazoles; D014344:Trypanocidal Agents; C009999:benzonidazole
keywords: Trypanosoma cruzi; amastigote; azlactone; cytotoxicity; synthetic derivatives; trypanocidal