Ferroptosis Regulates the Biofilm Formation and Antifungal Drug Resistance of Candida albicans

Objectives Candida albicans ( C. albicans ) biofilm serves as a major cause of Candida-related infections. However, the available antifungal agents are limited in variety, and the emergence of drug resistance has complicated clinical treatment. Ferroptosis shows promise as a novel therapeutic strategy for combating fungal infections. This study aimed to investigate the effects of ferroptosis on the biofilm formation of C. albicans , as well as its susceptibility to antifungal agents. Materials and methods C. albicans biofilm was treated with a ferroptosis inducer (erastin, 0-50 μM). Initially, erastin’s regulatory effects on oxidative stress were quantified by reactive oxygen species production and mitochondrial membrane potential. Subsequently, ferroptosis induction was validated by measuring malondialdehyde content, glutathione (GSH) content, and iron (Fe) ion concentration. Ferroptosis-associated gene expression was analysed by real-time quantitative PCR. Morphological changes in mitochondria and biofilm hyphal structures were observed. The metabolic activity and antifungal susceptibility were assessed. Finally, transcriptome sequencing (RNA-Seq) and the rescue assays were performed. Results Erastin (0-50 μM) treatment induced typical ferroptotic characteristics in C. albicans . Compared with the untreated group, erastin significantly elevated reactive oxygen species level, malondialdehyde content, and intracellular iron concentration, while decreasing mitochondrial membrane potential and GSH content, accompanied by the upregulated expression of ferroptosis-related genes. Moreover, erastin triggered mitochondrial shrinkage, membrane structural damage, and enhanced autophagic activity in C. albicans . Erastin also dose-dependently inhibited biofilm formation and hyphal growth, and reduced antifungal resistance. RNA-Seq analysis further verified transcriptomic alterations associated with metabolism, hyphal development, and pathogenicity. Ferroptosis inhibition reverses erastin-induced biofilm viability impairment and GSH depletion. Conclusion Ferroptosis modulates biofilm formation and antifungal drug resistance in C. albicans , potentially through exacerbated oxidative stress and lipid peroxidation accumulation. Clinical relevance Ferroptosis may be a potential regulatory mechanism of C. albicans biofilm drug resistance, which is expected to provide a promising novel strategy for the clinical management of C. albicans -related infections.