Evaluation of an Antifungal Agent Against Nakaseomyces Glabratus in the in Vivo Model Galleria Mellonella.

The clinical management of Nakaseomyces glabratus is becoming increasingly difficult because of its intrinsic and acquired resistance to multiple antifungal drugs, particularly azoles. This situation highlights the urgent need for new antifungal agents. In this study, the antifungal efficacy and toxicity profile of an organometallic compound, named FE1, was evaluated in the in vivo model Galleria mellonella infection model. Larvae were inoculated with a standardized suspension of N. glabratus CBS138 and treated with FE1 or fluconazole at different concentrations (0.4, 4.0, and 20 mg/kg). Survival and fungal burden (CFU/larva) were monitored at defined time points post-inoculation (24, 120 and 360 h). The results obtained in this study show that the model of N. glabratus infection in G. mellonella is suitable to evaluate toxicity, antifungal efficacy and evolution of the infection in response to antifungal treatments. In this context, compound FE1 showed significant antifungal activity, superior to that of fluconazole in parameters evaluated, such as survival and fungal burden, while melanization was monitored as a qualitative visual indicator of infection progression. The dose-dependent response observed in both survival and CFU/larva reduction assays, together with the complete protection in the groups treated with 20 mg/kg FE1 suggests a high therapeutic potential of this compound against N. glabratus infections.