AUTHOR=Maia Carolina Medeiros de Almeida , Pasetto Silvana , Nonaka Cassiano Francisco Weege , Costa Edja Maria Melo de Brito , Murata Ramiro Mendonça 

TITLE=Yeast-Host Interactions: Anadenanthera colubrina Modulates Virulence Factors of C. albicans and Inflammatory Response In Vitro

JOURNAL=Frontiers in Pharmacology

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2021.629778

DOI=10.3389/fphar.2021.629778

ISSN=1663-9812

ABSTRACT=<p>Oral candidiasis is one of the most common fungal infections in humans. Its incidence has increased widely, as well as the antifungal resistance, demanding for the search for novel antifungal therapeutic agents. <italic>Anadenanthera colubrina</italic> (Vell.) Brenan is a plant species that has been proven to possess pharmacological effects, including antifungal and anti-inflammatory activities. This study evaluated <italic>in vitro</italic> the effects of standardized <italic>A. colubrina</italic> extract on virulence factors of <italic>Candida albicans</italic> and its regulation on immune response through <italic>C. albicans</italic>-host interaction. Antifungal activity was evaluated by Broth Microdilution Method against reference <italic>Candida</italic> strains (<italic>C. albicans</italic>, <italic>C. glabrata</italic>, <italic>C. tropicalis</italic>; <italic>C. dubliniensis</italic>). Anti-biofilm effect was performed on <italic>C. albicans</italic> mature biofilm and quantified by CFU/mL/g of biofilm dry weight. Proleotlytic enzymatic activities of proteinase and phospholipase were assessed by Azocasein and Phosphatidylcholine assays, respectively. Cytotoxicity effect was determined by Cell Titer Blue Viability Assay on Human Gingival Fibroblasts. Co-cultured model was used to analyze <italic>C. albicans</italic> coexisting with HGF by Scanning Electron Microscopy and fluorescence microscopies; gene expression was assessed by RT-PCR of <italic>C. albicans</italic> enzymes (SAP-1, PLB-1) and of host inflammatory cytokines (IL-6, IL-8, IL-1β, IL-10). Cytokines secretion was analysed by Luminex. The extract presented antifungal effect with MIC&lt;15.62 μg/ml against <italic>Candida</italic> strains. Biofilm and proteolytic activity were significant reduced at 312.4 μg/ml (20 × 15.62 μg/ml) extract concentration. Cell viability was maintained higher than 70% in concentrations up to 250 μg/ml (LD<sub>50</sub> = 423.3 μg/ml). Co-culture microscopies demonstrated a substantial decreased in <italic>C. albicans</italic> growth and minimal toxicity against host cells. Gene expressions of SAP-1/PLB-1 were significantly down-regulated and host immune response was modulated by a significant decreased on IL-6 and IL-8 cytokines secretion. <italic>A. colubrina</italic> had antifungal activity on <italic>Candida</italic> strains, antibiofilm, and anti-proteolytic enzyme effects against <italic>C. albicans</italic>. Presented low cytotoxicity to the host cells and modulatory effects on the host immune response.</p>