Dan Wang1, Ya Shen2, Jingzhi Ma3, Robert E W Hancock4, Markus Haapasalo5. 1. Department of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Faculty of Dentistry, Division of Endodontics, Department of Oral Biological and Medical Sciences, University of British Columbia, Vancouver, British Columbia, Canada. 2. Faculty of Dentistry, Division of Endodontics, Department of Oral Biological and Medical Sciences, University of British Columbia, Vancouver, British Columbia, Canada. 3. Department of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. 4. Centre for Microbial Diseases and Immunity Research, Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada. 5. Faculty of Dentistry, Division of Endodontics, Department of Oral Biological and Medical Sciences, University of British Columbia, Vancouver, British Columbia, Canada. Electronic address: markush@dentistry.ubc.ca.
Abstract
INTRODUCTION: The aim of this study was to evaluate the effect of DJK-5, a newly developed cationic antimicrobial peptide, on oral multispecies and Enterococcus faecalis biofilms alone or combined with the endodontic chelating agent EDTA in vitro. METHODS: Oral multispecies biofilms from 2 donors and E. faecalis VP3-181 biofilm were grown on collagen-coated hydroxyapatite disks. After incubation for 3 days or 3 weeks, the biofilms were exposed to sterile saline (negative control), 8.5% EDTA, 2% chlorhexidine digluconate (CHX), 5 μg/mL DJK-5, 10 μg/mL DJK-5, a mixture of 5 μg/mL DJK-5 and 8.5% EDTA (final concentration), or a mixture of 10 μg/mL DJK-5 and 8.5% EDTA, all for 1 and 3 minutes. The proportions of dead bacteria in the biofilms were assessed by the LIVE/DEAD staining (Thermo Fisher Scientific, Waltham, MA) and confocal microscopy. RESULTS: The peptide DJK-5 rapidly killed most bacteria in all biofilms, with significant differences to the control, 8.5% EDTA and 2% CHX (P < .01). Basically, a higher DJK-5 concentration and longer exposure (3 minutes) were more effective than a low concentration and short time exposure (P < .05). There were no significant differences in antibiofilm activities between DJK-5 used alone or in the mixture with 8.5% EDTA at either concentration. EDTA (8.5%) had no significant antimicrobial effect compared with the negative control (P > .05), but, unlike DJK-5 alone, the mixture retained the ability to remove smear layers. In peptide groups, there were no significant differences in dead bacteria proportions between 3-day and 3-week biofilms, except for 10 μg/mL DJK-5 used alone for 3 minutes on the multispecies biofilms. CONCLUSIONS: DJK-5 exerted antibiofilm ability on E. faecalis and oral multispecies biofilms grown on hydroxyapatite disks, both alone and when combined with 8.5% EDTA.
INTRODUCTION: The aim of this study was to evaluate the effect of DJK-5, a newly developed cationic antimicrobial peptide, on oral multispecies and Enterococcus faecalis biofilms alone or combined with the endodontic chelating agent EDTA in vitro. METHODS: Oral multispecies biofilms from 2 donors and E. faecalis VP3-181 biofilm were grown on collagen-coated hydroxyapatite disks. After incubation for 3 days or 3 weeks, the biofilms were exposed to sterile saline (negative control), 8.5% EDTA, 2% chlorhexidine digluconate (CHX), 5 μg/mL DJK-5, 10 μg/mL DJK-5, a mixture of 5 μg/mL DJK-5 and 8.5% EDTA (final concentration), or a mixture of 10 μg/mL DJK-5 and 8.5% EDTA, all for 1 and 3 minutes. The proportions of dead bacteria in the biofilms were assessed by the LIVE/DEAD staining (Thermo Fisher Scientific, Waltham, MA) and confocal microscopy. RESULTS: The peptide DJK-5 rapidly killed most bacteria in all biofilms, with significant differences to the control, 8.5% EDTA and 2% CHX (P < .01). Basically, a higher DJK-5 concentration and longer exposure (3 minutes) were more effective than a low concentration and short time exposure (P < .05). There were no significant differences in antibiofilm activities between DJK-5 used alone or in the mixture with 8.5% EDTA at either concentration. EDTA (8.5%) had no significant antimicrobial effect compared with the negative control (P > .05), but, unlike DJK-5 alone, the mixture retained the ability to remove smear layers. In peptide groups, there were no significant differences in dead bacteria proportions between 3-day and 3-week biofilms, except for 10 μg/mL DJK-5 used alone for 3 minutes on the multispecies biofilms. CONCLUSIONS: DJK-5 exerted antibiofilm ability on E. faecalis and oral multispecies biofilms grown on hydroxyapatite disks, both alone and when combined with 8.5% EDTA.
Authors: Stella M F Lima; Mirna S Freire; Ana Paula C Cantuária; Danilo C M Martins; Ingrid A Amorim; Elaine M G L Dantas; Jade O Farias; Márcio B Castro; Jackson S Silva; Fernando A Barriviera; Maurício Barriviera; Jeeser A Almeida; Isadora A Uehara; Marcelo J B Silva; Ana Paula L Oliveira; Osmar N Silva; Robert E W Hancock; Octávio L Franco; Taia M B Rezende Journal: Clin Oral Investig Date: 2020-11-16 Impact factor: 3.573