IADR Abstract Archives
Epithelial-Mesenchymal Inhibitors May Have a Role in Inhibiting Pathogen-Induced EMT
Objectives: Subgingival plaque bacteria can initiate periodontitis by eliciting a persistent, excessive host inflammatory response caused by bacterial invasion into host tissue. This may induce an epithelial-mesenchymal transition (EMT) that compromises the epithelial barrier. This study aimed to determine the effects of periodontal pathogens on potential induction of oral keratinocyte EMT, migration and gene expression changes and to investigate potential EMT inhibitors for prevention or management of disease.
Methods: Porphyromonas gingivalis (PG), Fusobacterium nucleatum (FN) and Treponema denticola (TD) were cultured anaerobically, then oxygen-killed (OK) in atmospheric conditions at 37oC and applied to oral keratinocyte cultures in a 100:1 bacterium to epithelial cell ratio. 5µM curcumin was dissolved in 0.15M sodium hydroxide (NaOH) and sterilised PBS before addition to cell cultures. Cell counts were determined manually and cell migration was assessed in a 500µm wound area formed by Ibidi® 2-well inserts. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed for epithelial and mesenchymal markers after 8-days in culture.
Results: Cell numbers of keratinocytes grown in the presence of OK TD were significantly increased (P<0.01) but increased keratinocyte cell numbers were significantly reduced by addition of curcumin after 8-day exposure (P<0.05). Curcumin significantly reduced OK TD induced % wound gap closure from 56.15% to 29.54% (P<0.001) after 48hrs. Significant down-regulation of epithelial markers E-cadherin, Cytokeratin-5 and Desmoplakin-1 after 8-day exposure to OK PG, FN and TD were significantly inhibited by curcumin addition after qRT-PCR analysis (P<0.05 to P<0.001). Simultaneously, up-regulation of mesenchymal markers, Snail-1, N-cadherin, Vimentin and MMP-9 were significantly inhibited by curcumin (P<0.05 to P<0.001).
Conclusions: OK periodontal pathogens promote an EMT response in oral keratinocytes through gene expression changes leading to increased cell growth and migration. Curcumin appears to inhibit the responses eliciting EMT by periodontal pathogens, providing a potential therapeutic role in preventing or managing periodontitis progression by maintaining epithelial barrier integrity.
Methods: Porphyromonas gingivalis (PG), Fusobacterium nucleatum (FN) and Treponema denticola (TD) were cultured anaerobically, then oxygen-killed (OK) in atmospheric conditions at 37oC and applied to oral keratinocyte cultures in a 100:1 bacterium to epithelial cell ratio. 5µM curcumin was dissolved in 0.15M sodium hydroxide (NaOH) and sterilised PBS before addition to cell cultures. Cell counts were determined manually and cell migration was assessed in a 500µm wound area formed by Ibidi® 2-well inserts. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed for epithelial and mesenchymal markers after 8-days in culture.
Results: Cell numbers of keratinocytes grown in the presence of OK TD were significantly increased (P<0.01) but increased keratinocyte cell numbers were significantly reduced by addition of curcumin after 8-day exposure (P<0.05). Curcumin significantly reduced OK TD induced % wound gap closure from 56.15% to 29.54% (P<0.001) after 48hrs. Significant down-regulation of epithelial markers E-cadherin, Cytokeratin-5 and Desmoplakin-1 after 8-day exposure to OK PG, FN and TD were significantly inhibited by curcumin addition after qRT-PCR analysis (P<0.05 to P<0.001). Simultaneously, up-regulation of mesenchymal markers, Snail-1, N-cadherin, Vimentin and MMP-9 were significantly inhibited by curcumin (P<0.05 to P<0.001).
Conclusions: OK periodontal pathogens promote an EMT response in oral keratinocytes through gene expression changes leading to increased cell growth and migration. Curcumin appears to inhibit the responses eliciting EMT by periodontal pathogens, providing a potential therapeutic role in preventing or managing periodontitis progression by maintaining epithelial barrier integrity.