Ebselen Optimized the Therapeutic Effects of Silver Nanoparticles for Periodontal Treatment

Objective: Silver nanoparticles (AgNPs) possess excellent antibacterial effects on periodontal pathogens, but their clinical application is limited mainly due to their cytotoxicity through inducing oxidative stress in human cells.Ebselen disrupts the reactive oxygen species (ROS) scavenging in bacteria and relieves oxidative stress in mammalian cells.This study aimed to assess the antibacterial and anti-inflammatory effects of AgNPs and ebselen as well as the protective effect of ebselen, to further provide the theoretical basis for their future application in periodontal treatment.Methods: The antibacterial and anti-biofilm effects of the synthesized AgNPs combined with ebselen were assessed on Porphyromonas gingivalis (P.gingivalis), Streptococcus gordonii (S. gordonii), and Fusobacterium nucleatum (F.nucleatum) in planktonic condition and as biofilms.In addition, the intracellular bactericidal efficiency of AgNPs and ebselen was evaluated in P. gingivalis-infected human gingival fibroblasts (HGFs).The cytotoxicity, intracellular ROS levels, and potential antioxidative enzymes were detected in HGFs treated with AgNPs and ebselen.Further, the anti-inflammatory effects were evaluated by in vitro and in vivo experiments.Results: The combination of AgNPs and ebselen showed excellent antibacterial effects against planktonic P. gingivalis and F. nucleatum and synergistic antibiofilm effects on all mono-and multi-species biofilms.In addition, ebselen significantly enhanced the intracellular bactericidal efficiency of AgNPs.Furthermore, ebselen combined with up to 20 μg/mL AgNPs showed no obvious cytotoxicity to HGFs.Evidently, ebselen alleviated the AgNPs-induced ROS by increasing the levels of glutathione and superoxide dismutase 2.Moreover, AgNPs and ebselen together declined the release of P. gingivalis-stimulated inflammatory cytokines both in vitro and in vivo, and reduced alveolar bone resorption effectively.Conclusion: AgNPs combined with ebselen would be an effective adjuvant for periodontal treatment owing to their synergistic antibacterial and anti-inflammatory effects.