HBD-1, -2, -3, and -4 were synthesized and investigated the susceptibility against E. faecalis. Also, the neutralizing effects of HBDs on cytokine and intercellular adhesion molecule 1 (ICAM-1) expression by activity of E. faecalis and Ef LTA were analyzed using enzyme-linked immunosorbent assay and flow cytometry.
HBD-1 and -2 were weakly susceptible, and HBD-3 and HBD-4 were strongly susceptible to E. faecalis. All of the HBDs exhibited neutralizing effects on the activity of Ef LTA, and HBD-3 strongly neutralized the activity of E. faecalis in tumor necrosis factor-α, interleukin-8, and ICAM-1 expression. The neutralizing effects of HBDs were to inhibit E. faecalis or Ef LTA binding to the host cells.
These results suggest that the induction of HBDs might have great potential as endodontic therapeutic agents.