Antibiofilm Activity of LL-37 Peptide and D-Amino Acids Associated with Antibiotics Used in Regenerative Endodontics on an Ex Vivo Multispecies Biofilm Model.
Pereira. Ana C C ACC; Aguiar. Alana P S APS; Araujo. Leticia M P LMP; Dantas. Larissa O LO; Mayer. Marcia P A MPA; Karygianni. Lamprini L; Thurnheer. Thomas T; Pinheiro. Ericka T ET
Key Findings
- LL-37 alone did not significantly cut biofilm bacteria.
- The standard triple‑antibiotic paste (TAP) alone also showed no meaningful reduction.
- Combining LL-37 with TAP gave a modest 1‑log drop in bacterial counts (7‑log vs 8‑log in control).
- D‑amino acids, alone or with TAP, had no antibacterial effect.
Practical Outcomes
- For most DIY health enthusiasts, the result suggests LL-37 isn’t a stand‑alone mouth‑biofilm killer and only adds a small boost when paired with standard dental antibiotics. The modest benefit is unlikely to justify using LL-37 in everyday oral care protocols, especially given the limited effect and lack of safety data for self‑administration.
Summary
The study tested a natural antimicrobial peptide called LL-37, some D‑amino acids, and a common dental antibiotic mix (TAP) on a complex tooth‑root biofilm. Only the combo of LL-37 plus the antibiotics reduced bacterial numbers a little (about 1 log), while each thing alone did not work better than doing nothing.
Abstract
The antimicrobial peptide LL-37 and D-amino acids (D-AAs) have been proposed as antibiofilm agents. Therefore, this study aimed to test the antimicrobial effect of antibiofilm agents associated with antibiotics used in regenerative endodontic procedures (the triple antibiotic paste—TAP: ciprofloxacin + metronidazole + minocycline). An endodontic-like biofilm model grown on bovine dentin discs was used in this study. After 21-day growth, the biofilms were treated with 1 mg/mL TAP, 10 μM LL-37, an association of LL-37 + TAP, 40 mM D-AAs solution, an association of D-AAs + TAP, and phosphate-buffered saline (negative control). Colony forming unit (CFU) data were analyzed by two-way ANOVA and Tukey’s multiple comparison test (p < 0.05). LL-37 + TAP showed the best antibacterial activity (7-log10 CFU/mL ± 0.5), reaching a 1 log reduction of cells in relation to the negative control (8-log10 CFU/mL ± 0.7) (p < 0.05). In turn, no significant reduction in bacterial cells was observed with TAP, LL-37, D-AAs, and D-AAs + TAP compared to the negative control. In conclusion, the combination of antibiotics and LL-37 peptide showed mild antibacterial activity, while the combination of antibiotics and D-AAs showed no activity against complex biofilms.
Study Information
pubmed
2022
2022-10-24T00:00:00.000Z
10.3390/life12111686
4
41