Potential use of an Antimicrobial Peptide, KSL-W for Endodontic Treatment

Objectives: Endodontic infections are caused by polymicrobial involving a combination of a variety of microbes. The control of root canal infection needs the use of high concentrations of various antibiotics. However, the antibiotic sensitivity of the bacteria found within the oral cavity is gradually decreasing. Furthermore, being in contact with pulp cells at the apical level, these antibiotics may be toxic. The use of antimicrobial peptides (AMP) could be a medical alternative to prevent and overcome the resistance against antibiotics and their cytotoxicity. We previously showed that a peptide, KSL-W was efficient in reducing in vitro microbial growth. The objective of this study was to evaluate the effect of KSL-W on human dental pulp stem cells (DPSC) adhesion, growth and migration.
Methods: DPSCs were cultured in the presence or absence of KSL-W at various concentrations (10, 50 and 100 µg/ml); or triple (ciprofloxacin, metronidazole, and minocycline; TA) antibiotics. Cell adhesion was investigated after 24h incubation using crystal violet staining. The DPSC proliferation was investigated by MTT assay, at 2 and 3 days. The effect of KSL-W on cell migration/wound healing was evaluated using an in vitro scratch assay.
Results: We demonstrated that KSL-W promoted DPSCs adhesion as compared to antibiotics. The cells being treated with KSL-W showed comparable morphology as non-treated cells (control). It is also interesting to note that KSL-W at 10 and 50 mg/ml, increased DPSC proliferation but not antibiotics. The increased cell growth promoted cell migration and wound scratch healing.
Conclusions: Compared to antibiotics, KSL-W promoted DPSC adhesion, proliferation and migration. KSL-W could be used as an endodontic antimicrobial agent for root canal treatment without harmful effects to the endodontic tissue. This study was supported by funds from the Laval University Foundation and the Canadian Academy of Endodontics.