title: Eugenol inhibited the antimicrobial functions of neutrophils.
abstract: Eugenol-containing restorative materials are commonly used for vital pulp therapy. A well-regulated host defense response is pivotal for the success of vital pulp therapy. The present study was to assess the effects of eugenol on the antimicrobial functions of polymorphonuclear leukocytes (neutrophils). Treatment with eugenol (< or = 1.25 mmol/L) for 30 minutes did not significantly affect the viability of neutrophils. However, preincubation of neutrophils with eugenol (1.25 mmol/L and 2.5 mmol/L) abolished their bactericidal activity against oral pathogens Streptococcus mutans and Actinobacillus actinomycetemcomitans. In addition, through the suppression of the extracellular release of myeloperoxidase and the intracellular production of reactive oxygen species, eugenol at sufficient concentrations impaired the activation of neutrophils by cytochalasin B and fMet-Leu-Phe (CB/fMLP). These results suggested that the antimicrobial functions of neutrophils were interfered by eugenol, and the inhibitory effects of eugenol (< or = 1.25 mmol/L) were not due to direct killing of neutrophils.
authors.affiliation: Faculty of Dentistry, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Dai-Chian
authors.initials: DC
authors.lastname: Chen
authors.forename: Ya-Yun
authors.initials: YY
authors.lastname: Lee
authors.forename: Pei-Ying
authors.initials: PY
authors.lastname: Yeh
authors.forename: Jung-Chen
authors.initials: JC
authors.lastname: Lin
authors.forename: Yu-Lin
authors.initials: YL
authors.lastname: Chen
authors.forename: Shan-Ling
authors.initials: SL
authors.lastname: Hung
mesh_terms: D016976:Aggregatibacter actinomycetemcomitans / Q000502:physiology; D001770:Blood Bactericidal Activity / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D003571:Cytochalasin B / Q000494:pharmacology; D003764:Dental Materials / Q000494:pharmacology*; D005054:Eugenol / Q000494:pharmacology*; D006801:Humans; D008422:Materials Testing; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D018375:Neutrophil Activation / Q000187:drug effects; D009504:Neutrophils / Q000187:drug effects* / Q000502:physiology; D009195:Peroxidase / Q000037:antagonists & inhibitors; D017382:Reactive Oxygen Species / Q000037:antagonists & inhibitors; D013295:Streptococcus mutans / Q000502:physiology
chemical_list: D003764:Dental Materials; D017382:Reactive Oxygen Species; D003571:Cytochalasin B; D005054:Eugenol; D009240:N-Formylmethionine Leucyl-Phenylalanine; D009195:Peroxidase