Antimicrobial peptide GH12 as root canal irrigant inhibits biofilm and virulence of Enterococcus faecalis

作者：Yunfeng Li, Yi Wang, Xing Chen, Wentao Jiang, Xuelian Jiang, Yuhao Zeng, Xiao Li, Zening Feng, Jingjie Luo, Linglin Zhang · 发表于：International Endodontic Journal · 年份：2020 · DOI：10.1111/iej.13296 · 被引用次数：23 · 研究领域：Antimicrobial Peptides and Activities、Oral microbiology and periodontitis research、Endodontics and Root Canal Treatments

Abstract Aim The objectives of this laboratory‐based study were to investigate the effects of GH12 on Enterococcus faecalis biofilm and virulence. Methodology Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of GH12 against E. faecalis were first determined. A time‐kill assay was further conducted. The effects of GH12 on the expression of virulence and stress genes in E. faecalis were evaluated by RT‐qPCR. Crystal violet stain was used to investigate the effects of GH12 on E. faecalis biofilm formation and 1‐day‐old biofilm . Finally, an ex vivo tooth model contaminated with E. faecalis was used to evaluate the antimicrobial activity of GH12 as an irrigant by CFU counting, SEM and CLSM. One‐way anova and Tukey’s multiple comparisons test were used to compare the differences amongst groups (α = 0.05). Results The MICs and MBCs of GH12 against E. faecalis were 8.0 ± 0.0 and 16.0 ± 0.0 mg L −1 , respectively, and GH12 at 32.0 mg L −1 reduced the bacterial numbers by more than 99.9% within 1 min. Various virulence genes ( efaA , esp and gelE ) and stress genes ( dnaK , groEL , ctsR and clpPBCEX ) in E. faecalis were significantly downregulated by GH12 at sub‐MIC levels ( P < 0.05) . Additionally, both E. faecalis biofilm formation and the biomass of 1‐day‐old E. faecalis biofilm were significantly reduced by GH12 ( P < 0.05). Elimination of E. faecalis in biofilms from root canal walls was achieved through irrigation with 64.0 mg L −1 GH12...