Action mechanism of naphthofuranquinones against fluconazole-resistant Candida tropicalis strains evidenced by proteomic analysis: The role of increased endogenous ROS

Microb Pathog. 2018 Apr:117:32-42. doi: 10.1016/j.micpath.2017.12.016. Epub 2017 Dec 8.

Abstract

The increased incidence of candidemia in terciary hospitals worldwide and the cross-resistance frequency require the new therapeutic strategies development. Recently, our research group demonstrated three semi-synthetic naphthofuranquinones (NFQs) with a significant antifungal activity in a fluconazole-resistant (FLC) C. tropicalis strain. The current study aimed to investigate the action's preliminary mechanisms of NFQs by several standardized methods such as proteomic and flow cytometry analyzes, comet assay, immunohistochemistry and confocal microscopy evaluation. Our data showed C. tropicalis 24 h treated with all NFQs induced an expression's increase of proteins involved in the metabolic response to stress, energy metabolism, glycolysis, nucleosome assembly and translation process. Some aspects of proteomic analysis are in consonance with our flow cytometry analysis which indicated an augmentation of intracellular ROS, mitochondrial dysfunction and DNA strand breaks (neutral comet assay and γ-H2AX detection). In conclusion, our data highlights the great contribution of ROS as a key event, probably not the one, associated to anti-candida properties of studied NFQs.

Keywords: Action mechanism; Fluconazole-resistant Candida tropicalis strain; Naphthofuranquinones; Proteomic analysis; ROS.

MeSH terms

  • Antifungal Agents / chemical synthesis
  • Antifungal Agents / chemistry
  • Antifungal Agents / pharmacology*
  • Candida tropicalis / drug effects*
  • Candida tropicalis / genetics
  • Candida tropicalis / metabolism*
  • Candidemia / microbiology
  • Cell Cycle / drug effects
  • DNA Damage / drug effects
  • DNA, Fungal / genetics
  • Drug Resistance, Fungal / drug effects*
  • Drug Resistance, Fungal / physiology*
  • Energy Metabolism / drug effects
  • Fluconazole / pharmacology
  • Glycolysis / drug effects
  • Membrane Potential, Mitochondrial / drug effects
  • Microbial Sensitivity Tests
  • Mitochondria / drug effects
  • Naphthoquinones / chemical synthesis
  • Naphthoquinones / chemistry
  • Naphthoquinones / pharmacology*
  • Proteomics*
  • Reactive Oxygen Species / metabolism*
  • Stress, Psychological

Substances

  • Antifungal Agents
  • DNA, Fungal
  • Naphthoquinones
  • Reactive Oxygen Species
  • Fluconazole