AUTHOR=Andriani Gabriella Maria , Spoladori Lais Fernanda de Almeida , Fabris Marciéli , Camargo Priscila Goes , Pereira Patrícia Morais Lopes , Santos Jussevania Pereira , Bartolomeu-Gonçalves Guilherme , Alonso Lais , Lancheros Cesar Armando Contreras , Alonso Antonio , Nakamura Celso Vataru , Macedo Fernando , Pinge-Filho Phileno , Yamauchi Lucy Megumi , Bispo Marcelle de Lima Ferreira , Tavares Eliandro Reis , Yamada-Ogatta Sueli Fumie 

TITLE=Synergistic antifungal interaction of N-(butylcarbamothioyl) benzamide and amphotericin B against Cryptococcus neoformans

JOURNAL=Frontiers in Microbiology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2023.1040671

DOI=10.3389/fmicb.2023.1040671

ISSN=1664-302X

ABSTRACT=<sec><title>Introduction</title><p><italic>Cryptococcus neoformans</italic> is one of the leading causes of invasive fungal infections worldwide. Cryptococcal meningoencephalitis is the main challenge of antifungal therapy due to high morbidity and mortality rates, especially in low- and middle-income countries. This can be partly attributed to the lack of specific diagnosis difficulty accessing treatment, antifungal resistance and antifungal toxicity.</p></sec><sec><title>Methods</title><p>In the present study, the effect of the synthetic thiourea derivative <italic>N</italic>-(butylcarbamothioyl) benzamide (BTU-01), alone and combined with amphotericin B (AmB), was evaluated in planktonic and sessile (biofilm) cells of <italic>C. neoformans</italic>.</p></sec><sec><title>Results</title><p>BTU-01 alone exhibited a fungistatic activity with minimal inhibitory concentrations (MICs) ranging from 31.25 to 62.5 μg/mL for planktonic cells; and sessile MICs ranging from 125.0 to 1000.0 μg/mL. BTU-01 caused a concentration-dependent inhibitory activity on cryptococcal urease and did not interfere with plasma membrane fluidity. Molecular docking was performed on <italic>Canavalia ensiformis</italic> urease, and BTU-01 showed relevant interactions with the enzyme. The combination of BTU-01 and AmB exhibited synergistic fungicidal activity against planktonic and sessile cells of <italic>C. neoformans.</italic> Microscopic analysis of <italic>C. neoformans</italic> treated with BTU-01, alone or combined with AmB, revealed a reduction in cell and capsule sizes, changes in the morphology of planktonic cells; a significant decrease in the number of cells within the biofilm; and absence of exopolymeric matrix surrounding the sessile cells. Neither hemolytic activity nor cytotoxicity to mammalian cells was detected for BTU-01, alone or combined with AmB, at concentrations that exhibited antifungal activity. BTU-01 also displayed drug-likeness properties.</p></sec><sec><title>Conclusion</title><p>These results indicate the potential of BTU-01, for the development of new strategies for controlling <italic>C. neoformans</italic> infections.</p></sec>