Derivado da 7-hidroxicumarina apresenta potencial antifúngico contra espécies de Candida e baixa citotoxicidade contra células humanas: um estudo in silico e in vitro

Abstract

Introduction: The treatment of oral candidiasis is a challenge in dentistry due to the resistance of microrganisms and the toxicity resulting from antifungal therapy and, therefore, the prospection of new therapeutic agents is necessary. Objective: To determine in silico and in vitro antifungal activity against Candida species and cytotoxicity against human cells of the compound 7-(Pentyloxy)-2H-chromen-2-one. Methodology: The interaction of the compound with fungal targets was analyzed using molecular Docking. Molecular dynamics simulations were performed to assess the flexibility and stability of interactions with 1,3β-glucan synthase, squalene epoxidase and 14-α-desmethylase targets. The in vitro activity against Candida species, the possible mechanisms of action, the time for inhibition of fungal growth and the association of the compound with nystatin were evaluated by the checkerboard method. The cytotoxicity of the compound on human keratinocytes (HaCat) was investigated in vitro. Results: Docking indicated affinity for all evaluated targets, 1,3β-glucan synthase, squalene epoxidase, δ-14-sterol reductase, 14-α-desmethylase and thymidylate synthase, with the respective values of binding energy -100.39; -81.20; -88.15; -73.15 and -74.80 Kcal/mol. Molecular dynamics simulation showed that the compound was able to establish strong bonds and remained in the active site of the evaluated targets. The Minimum Inhibitory Concentration (MIC) and Minimum Fungicide Concentration (MFC) values ranged from 67.16μM (15.6μg/mL) to 537.28μM (125.0μg/mL). The probable mode of action involves plasma membrane function. MIC-125μg/mL (538.1μM) and MICx2-250μg/mL (1076μM) prevented fungal growth for at least 24h, and the death kinetics indicated that MIC was able to inhibit growth for up to 36h. CIMx2, in turn, maintained growth inhibition throughout the analysis period. The association with nystatin was indifferent for antifungal action (ICIF=1.25). It presented IC50 of 100μM indicating low cytotoxic activity for human keratinocytes. Conclusion: The compound showed antifungal action in the in silico test, confirmed in the in vitro tests and showed low cytotoxicity for keratinocytes, showing promising results for a possible alternative in the treatment of oral candidiasis. In-depth studies of bioavailability and in vivo toxicity are needed to guide clinical trials.