Toxicogenetic profiling of an antifungal lawsone silver salt: in silico and in vitro analysis in 2D and 3D mammalian models.

The development of novel metal-based antifungals requires rigorous characterization of their toxicological mechanisms to ensure patient safety. This study investigated the toxicogenetic profile and cellular interactions of lawsone silver salt (LSS), a compound with established activity against Sporothrix spp. and emerging multidrug-resistant pathogens. Antifungal efficacy was confirmed against planktonic Aspergillus fumigatus, Candida albicans, and C. auris (MIC 1.45-23.2 µM), with significant anti-biofilm activity against C. albicans (185.9 µM) and A. fumigatus (92.9 µM). In silico ADMET modeling predicted high oral bioavailability and blood-brain barrier permeability, despite the genotoxicity alerts. Experimentally, LSS (0.005-50 µg/plate) was non-mutagenic in the Salmonella/microsome assay (TA1535, TA97a, TA98, TA100, and TA102), regardless of the metabolic activation. However, LSS (0.5-500 µM) induced significant genomic instability in HepG2 cells. The micronucleus assay revealed a dose-dependent increase in micronuclei, nucleoplasmic bridges, and nuclear buds, indicating clastogenic and aneugenic effects. Comparative cytotoxicity was evaluated in BALB/3T3 fibroblasts using 2D monolayers and scaffold-based 3D models (0.005-5000 µM). In 2D cultures, LSS exhibited potent cytotoxicity (CC50: 2.7-19.9 µM). Crucially, the 3D microenvironment significantly attenuated these effects (CC50: 1,797-1,919 µM), suggesting a markedly higher safety margin in physiologically relevant tissue architectures. These findings demonstrate that while LSS induces chromosomal damage in human cells, its toxicity is fundamentally modulated by cellular organization, providing essential data for risk assessment and therapeutic optimization of naphthoquinone derivatives.