Quercetin inhibits virulence properties of Porphyromas gingivalis in periodontal disease

Abstract

Porphyromonas gingivalis is a causative agent in the onset and progression of periodontal disease. This study aims to investigate the effects of quercetin, a natural plant product, on P. gingivalis virulence properties including gingipain, haemagglutinin and biofilm formation. Antimicrobial effects and morphological changes of quercetin on P. gingivalis were detected. The effects of quercetin on gingipains activities and hemolytic, hemagglutination activities were evaluated using chromogenic peptides and sheep erythrocytes. The biofilm biomass and metabolism with different concentrations of quercetin were assessed by the crystal violet and MTT assay. The structures and thickness of the biofilms were observed by confocal laser scanning microscopy. Bacterial cell surface properties including cell surface hydrophobicity and aggregation were also evaluated. The mRNA expression of virulence and iron/heme utilization was assessed using real time-PCR. Quercetin exhibited antimicrobial effects and damaged the cell structure. Quercetin can inhibit gingipains, hemolytic, hemagglutination activities and biofilm formation at sub-MIC concentrations. Molecular docking analysis further indicated that quercetin can interact with gingipains. The biofilm became sparser and thinner after quercetin treatment. Quercetin also modulate cell surface hydrophobicity and aggregation. Expression of the genes tested was down-regulated in the presence of quercetin. In conclusion, our study demonstrated that quercetin inhibited various virulence factors of P. gingivalis.

Anti-biofilm activities of coumarin as quorum sensing inhibitor for Porphyromonas gingivalis

“…The aggregation assay was performed as previously described with minor modifications [ 25 ]. Briefly, an overnight P. gingivalis suspension was harvested by centrifugation at 12,000 × g for 30 s, washed twice with PBS, and resuspended in the same buffer.…”

“…The cell surface hydrophobicity of P. gingivalis was determined by measuring adherence to n-hexadecane [ 25 ]. Briefly, bacterial cells cultured in BHI with different concentrations of coumarin were washed twice in phosphate urea magnesium buffer (PUM containing 0.115 M K 2 HPO 4 , 0.05 M KH 2 PO 4 , 0.03 M urea, 0.8 mM MgSO 4 · 7H 2 O; pH 7.2) by centrifugation at 10,000 × g for 5 min and re-suspended in the same buffer.…”

“…The effect of coumarin on P. gingivalis biofilm formation was examined by the 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazoliumbromide (MTT) and crystal violet method with minor modification [ 25 , 27 ]. A 200 μL aliquot of P. gingivalis suspension was grown in BHI supplemented with different concentrations of coumarin for different times (16 and 48 h) at 37°C in 96-well polystyrene plates.…”

The Application of Small Molecules to the Control of Typical Species Associated With Oral Infectious Diseases

“…A natural polyphenol, Quercetin (3,3′,4′,5,7-pentahydroxyflavone), can inhibit gingipains activities and biofilm formation at sub-MIC concentrations. In addition, quercetin down-regulates the expression of virulence-associated genes of P. gingivalis ( He et al., 2020 ). Quantum curcumin, a derivative of curcumin, shows notable inhibitory effects on planktonic cells and biofilms of P. gingivalis , particularly via inhibition of gingipain R and K ( Singh et al., 2019 ).…”

Periodontitis and Accelerated Biological Aging: A Geroscience Approach

“…Quercetin is a flavonoid, which has potent anti-inflammatory, antibacterial, and antioxidant effects. Its administration in an in vivo model of periodontitis reduced alveolar bone loss by decreasing osteoclastic activity, apoptosis, and inflammation and inhibiting various virulence factors of P. gingivalis (He et al 2020). Also, the effect of curcumin on reducing the oxidative stress biomarkers in the GCF and on enhancing the osteogenic potential of human PDLSCs was tested (Tan et al 2021).…”