Iron Chelator Deferasirox Reduces Candida albicans Invasion of Oral Epithelial Cells and Infection Levels in Murine Oropharyngeal Candidiasis

Antimicrob Agents Chemother. 2019 Mar 27;63(4):e02152-18. doi: 10.1128/AAC.02152-18. Print 2019 Apr.

Abstract

Candida albicans, the causative agent of mucosal infections, including oropharyngeal candidiasis (OPC), as well as bloodstream infections, is becoming increasingly resistant to existing treatment options. In the absence of novel drug candidates, drug repurposing aimed at using existing drugs to treat off-label diseases is a promising strategy. C. albicans requires environmental iron for survival and virulence, while host nutritional immunity deploys iron-binding proteins to sequester iron and reduce fungal growth. Here we evaluated the role of iron limitation using deferasirox (an FDA-approved iron chelator for the treatment of patients with iron overload) during murine OPC and assessed deferasirox-treated C. albicans for its interaction with human oral epithelial (OE) cells, neutrophils, and antimicrobial peptides. Therapeutic deferasirox treatment significantly reduced salivary iron levels, while a nonsignificant reduction in the fungal burden was observed. Preventive treatment that allowed for two additional days of drug administration in our murine model resulted in a significant reduction in the number of C. albicans CFU per gram of tongue tissue, a significant reduction in salivary iron levels, and significantly reduced neutrophil-mediated inflammation. C. albicans cells harvested from the tongues of animals undergoing preventive treatment had the differential expression of 106 genes, including those involved in iron metabolism, adhesion, and the response to host innate immunity. Moreover, deferasirox-treated C. albicans cells had a 2-fold reduction in survival in neutrophil phagosomes (with greater susceptibility to oxidative stress) and reduced adhesion to and invasion of OE cells in vitro Thus, deferasirox treatment has the potential to alleviate OPC by affecting C. albicans gene expression and reducing virulence.

Keywords: Candida albicans; deferasirox; drug repurposing; iron; iron chelation; neutrophils; oral epithelial cells; oropharyngeal candidiasis; saliva.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Antifungal Agents / pharmacology
  • Candida albicans / drug effects*
  • Candida albicans / pathogenicity
  • Candidiasis, Oral / drug therapy*
  • Candidiasis, Oral / microbiology
  • Candidiasis, Oral / pathology
  • Cell Adhesion / drug effects
  • Cells, Cultured
  • Deferasirox / pharmacology*
  • Drug Repositioning
  • Epithelial Cells / microbiology*
  • Female
  • Gene Expression Regulation, Fungal / drug effects
  • Humans
  • Iron / metabolism
  • Iron Chelating Agents / pharmacology*
  • Mice
  • Mice, Inbred C57BL
  • Mouth Mucosa / cytology
  • Mouth Mucosa / microbiology*
  • Mouth Mucosa / pathology
  • Neutrophils / microbiology
  • Oxidative Stress / drug effects
  • Saliva / chemistry
  • Tongue / microbiology

Substances

  • Antifungal Agents
  • Iron Chelating Agents
  • Iron
  • Deferasirox