Promising antifungal activity of new oxadiazole against Candida krusei

PLoS One. 2020 Jan 14;15(1):e0227876. doi: 10.1371/journal.pone.0227876. eCollection 2020.

Abstract

Candida krusei is one of the most common agents of invasive candidiasis and candidemia worldwide, leading to high morbidity and mortality rates. This species has become a problem due to its intrinsic resistance and reduced susceptibility to azoles and polyenes. Moreover, the number of antifungal drugs available for candidiasis treatment is limited, demonstrating the urgent need for the discovery of novel alternative therapies. In this work, the in vivo and in vitro activities of a new oxadiazole (LMM11) were evaluated against C. krusei. The minimum inhibitory concentration ranged from 32 to 64 μg/mL with a significant reduction in the colony forming unit (CFU) count (~3 log10). LMM11 showed fungicidal effect, similar to amphotericin, reducing the viable cell number (>99.9%) in the time-kill curve. Yeast cells presented morphological alterations and inactive metabolism when treated with LMM11. This compound was also effective in decreasing C. krusei replication inside and outside macrophages. A synergistic effect between fluconazole and LMM11 was observed. In vivo treatment with the new oxadiazole led to a significant reduction in CFU (0.85 log10). Furthermore, histopathological analysis of the treated group exhibited a reduction in the inflammatory area. Taken together, these results indicate that LMM11 is a promising candidate for the development of a new antifungal agent for the treatment of infections caused by resistant Candida species such as C. krusei.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amphotericin B / pharmacology
  • Antifungal Agents / chemistry*
  • Antifungal Agents / pharmacology
  • Candida / drug effects*
  • Candida / pathogenicity
  • Candidiasis / drug therapy*
  • Candidiasis / microbiology
  • Cell Survival / drug effects
  • Humans
  • Macrophages / drug effects
  • Oxadiazoles / chemistry*
  • Oxadiazoles / pharmacology
  • Stem Cells / drug effects

Substances

  • Antifungal Agents
  • Oxadiazoles
  • Amphotericin B

Grants and funding

This study was funded by National Council for Scientific and Technological Development (CNPq) (http://www.cnpq.br/) - Grant number 552276/2011-1 to ESK, TIES and the Coordination for the Improvement of Higher Education Personnel (CAPES) to DRF. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.