Inhibition of proinflammatory activities of major periodontal pathogens by aqueous extracts from elder flower (Sambucus nigra)

Background: Prolonged induction of excessive levels of inflammatory mediators contributes to the pathogenesis of chronic disease states, such as periodontitis. It is thus important to develop safe and effective anti-inflammatory strategies for therapeutic reasons. In this study, we determined the ability of aqueous extracts from elder flower (Sambucus nigra) to inhibit the proinflammatory activity of major virulence factors from the periodontal pathogens Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans. Methods: Monocytes/macrophages or neutrophils were incubated with whole cells of P. gingivalis, A. actinomycetemcomitans, or purified components thereof (lipopolysaccharide and fimbriae) in the absence or presence of elder flower extract and were assayed for cytokine production, integrin activation, or induction of the oxidative burst. Results: The elder flower extract was found to potently inhibit all proinflammatory activities tested. Investigation of the underlying mechanisms revealed that the anti-inflammatory extract inhibited activation of the nuclear transcription factor κB and of phosphatidylinositol 3-kinase. Conclusion: The elder flower extract displays useful anti-inflammatory properties that could be exploited therapeutically for the control of inflammation in human periodontitis.