Oxidative stress and antioxidant responses in Galleria mellonella following Candida albicans infection

Abstract

Candida albicans is one of the most common human fungal pathogens. C. albicans infections can range from superficial conditions, such as oral and vaginal candidiasis, to more severe, invasive infections, which can lead to life-threatening systemic diseases, particularly in immunocompromised individuals. In this study, the oxidative effects of C. albicans infection on the non-vertebrate model Galleria mellonella, were investigated. Levels of oxidative damage indicators, lipid peroxidation product, malondialdehyde (MDA), and antioxidant enzymes, including glutathione S-transferase (GST), superoxide dismutase (SOD), and catalase (CAT), were determined in C. albicans-infected G. mellonella larvae. Initially, CAT activity decreased at 2–4 h post-infection, followed by an increase at 6–8 h, while levels of MDA, GST, and SOD were elevated at 8 h, reflecting a dynamic antioxidant response. Furthermore, this study examines the interaction of gliotoxin, a mycotoxin, with antioxidant enzymes GST, SOD and CAT using molecular docking studies. Molecular docking revealed gliotoxin and β-glucan binding affinities of −6.8 kcal/mol with GST and SOD, and −6.5 and −7.2 kcal/mol with CAT, respectively. These findings indicate that G. mellonella provides an effective model for studying the interactions between C. albicans and the host.