Synergy and Mechanism of Leflunomide Plus Fluconazole Against Resistant Candida albicans: An in vitro Study

Enhanced Stable and Efficient of Dual-Ligand Zirconium-Based Metal-Organic Frameworks for Synergistic Photodynamic Inactivation

Porphyrins, known for generating toxic singlet oxygen (1O2) to combat bacteria, face challenges such as hydrophilicity and limited lifespan and 1O2 yield. Conversely, triterpenoid compounds like ammonium glycyrrhizinate (AG) offer antioxidative and antibacterial properties but lack efficacy and stability. Combining them in Metal-Organic Frameworks (MOFs) yields dual-ligand zirconium (Zr)-basedMOFs (M-TG), capitalizing on porphyrins' membrane-disrupting ability and AG's inhibition of bacterial membrane synthesis for a synergistic antibacterial effect. M-TG resolves activity loss, enhances reactive oxygen species (ROS) yield, and extends stability, achieving a remarkable 99.999% sterilization rate. This innovative approach maximizes ligand properties through synergistic effects, promising significant advancements in antibacterial material design.

Synergistic effect of eravacycline combined with fluconazole against resistant Candida albicans in vitro and in vivo

BACKGROUND

The limited availability of antifungal drugs for candidiasis and the persistent problem of drug resistance, necessitates the urgent development of new antifungal drugs and alternative treatment options.

RESEARCH DESIGN AND METHODS

This study examined the synergistic antifungal activity of the combination of eravacycline (ERV) and fluconazole (FLC) both in vitro by microdilution checkerboard assay and in vivo by Galleria mellonella model. The underlying synergistic mechanisms of this drug combination was investigated using RNA-sequencing and qPCR.

RESULTS

ERV (2 μg/mL) + FLC (0.25-0.5 μg/mL) had strong synergistic antifungal activity against resistant Candida albicans (C. albicans) in vitro, as evidenced by a fractional inhibitory concentration index of 0.0044-0.0088. In vivo experiments in Galleria mellonella larvae infected with resistant C. albicans revealed that ERV (2 μg/larva) + FLC (1 μg/larva) improved survival rates and reduced fungal burden. The results of RNA-sequencing and qPCR showed that the mechanism of synergistic inhibition on resistant C. albicans was related to the inhibition of DNA replication and cell meiosis.

CONCLUSIONS

These results indicate that the combination of ERV and FLC effectively inhibits resistant C. albicans both in vitro and in vivo and lay the foundation for a potential novel treatment option for candidiasis.