RESUMO
Periodontitis affects oral tissues and induces systemic inflammation, which increases the risk of cardiovascular disease and metabolic syndrome. Subgingival plaque accumulation is a trigger of periodontitis. Fusobacterium nucleatum (FN) contributes to subgingival biofilm complexity by intercalating with early and late bacterial colonizers on tooth surfaces. In addition, inflammatory responses to FN are associated with the progression of periodontitis. Nigella sativa Lin. seed, which is known as black cumin (BC), has been used as a herbal medicine to treat ailments such as asthma and infectious diseases. The current study examined the inhibitory effect of BC oil and its active constituents, thymol (TM) and thymoquinone (TQ), on FNassociated biofilm and inflammation. FNcontaining biofilms were prepared by cocultivation with an early dental colonizer, Actinomyces naeslundii (AN). The stability and biomass of FN/AN dual species biofilms were significantly higher compared with FN alone. This effect was retained even with prefixed cells, indicating that FN/AN coaggregation is mediated by physicochemical interactions with cell surface molecules. FN/AN biofilm formation was significantly inhibited by 0.1% TM or TQ. Confocal laser scanning microscopy indicated that treatment of preformed FN/AN biofilm with 0.01% of BC, TM or TQ significantly reduced biofilm thickness, and TQ demonstrated a cleansing effect equivalent to that of isopropyl methylphenol. TQ dosedependently suppressed TNFα production from a human monocytic cell line, THP1 exposed to FN, yet showed no toxicity to THP1 cells. These results indicated that oral hygiene care using TQ could reduce FNassociated biofilm and inflammation in gingival tissue.
Assuntos
Benzoquinonas/farmacologia , Biofilmes/efeitos dos fármacos , Fusobacterium nucleatum/efeitos dos fármacos , Fusobacterium nucleatum/fisiologia , Inflamação/metabolismo , Actinomyces/citologia , Actinomyces/efeitos dos fármacos , Actinomyces/fisiologia , Fusobacterium nucleatum/citologia , Gengiva/efeitos dos fármacos , Humanos , Microscopia Confocal , Periodontite/tratamento farmacológico , Periodontite/microbiologia , Óleos de Plantas/química , Células THP-1 , Timol/farmacologia , Fator de Necrose Tumoral alfa/metabolismoRESUMO
The development of a number of in vitro techniques for the evaluation of antiplaque effects of test agents has followed the characterization and culturing of plaque-forming microorganisms. Studies of the mechanism of action of chlorhexidine and clinical observations have assisted in defining critical aspects of these in vitro techniques. Such assays may play an increasingly important role in screening potential new agents as well as in the optimization of properties by chemical modification of new lead agents. In addition, data generated in the in vitro assay may assist the design of in vivo evaluations of new agents. Proper selection of in vitro techniques for these various functions in the pre-clinical development process may reduce the time and cost involved in the development of new antiplaque agents.