A small molecule II-6s inhibits Enterococcus faecalis biofilms.
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ABSTRACT: Background
Limitations of current intracanal irrigants such as sodium hypochlorite (NaOCl) and chlorhexidine (CHX) necessitate the development of novel antimicrobial agents to control endodontic infection.Aim
This study investigated the antimicrobial activities of a small molecule II-6s against Enterococcus faecalis associated with endodontic diseases.Methods
The susceptibility of E. faecalis to II-6s was evaluated by the microdilution method and time-kill assay. Microbial resistance was assessed by repeated exposure of E. faecalis to II-6s. Cytotoxicity of II-6s was evaluated by CCK-8 assay. Virulence gene expression of the II-6s-treated E. faecalis cells was measured by RT-qPCR. Bacterial reductions in the dentinal tubules were further assessed by confocal laser scanning microscopy.Results
II-6s exhibited potent antimicrobial activity against E. faecalis and down-regulated virulence-associated genes in E. faecalis. II-6s induced no drug resistance in E. faecalis with lower cytotoxicity as compared to NaOCl and CHX. More importantly, 0.003125% II-6s exhibited significant bactericidal effect against E. faecalis residing in the dentinal tubules, which was comparable to 5.25% NaOCl and 2% CHX.Conclusions
II-6s has excellent antimicrobial activity, moderate cytotoxicity and induces no drug resistance, and thus is a promising agent for the treatment of endodontic infection.
SUBMITTER: Kuang X
PROVIDER: S-EPMC8451641 | biostudies-literature |
REPOSITORIES: biostudies-literature
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