Enterococcus Faecalis LTA Activates NLRP3 Inflammasome by Promoting High Expression of ROS

doi:10.13701/j.cnki.kqyxyj.2018.02.002

Abstract

Abstract: Objective: To detect whetherEnterococcus faecalis LTA activates NLRP3 inflammasome by promotingreactive oxygen species expression. Methods: Mouse macrophages RAW264.7 cells were stimulated with Enterococcus faecalis LTA, and the expressions of NLRP3 protein and mRNA were detected by Western blot, ELISA, and real-time qPCR. Reduced nicotinamide adenine dinucleotide phosphatase oxidase inhibitor DPI inhibited the production of reactive oxygen species (ROS), which was detected by fluorescence staining and flow cytometry. Results: After LTA was applied to RAW264.7 cells for 24 hours, the expressions of protein and mRNA of NLRP3, Caspase-1, and IL-1βwere significantly higher than those of negative control group (P<0.05). The DPI could effectively inhibit the production of ROS.When ROS expression was inhibited, the expressions of NLRP3 inflammatory protein and mRNA were significantly reduced. Conclusion: LTA is the virulence factor of Enterococcus faecalis activating NLRP3 inflammasome, mainly by the production of ROS.

Key words: NLRP3 inflammasome, Enterococcus faecalis, LTA, ROS

CLC Number:

R781

WANG Li-na, YE Dan-dan, WANG Jiao-jiao, NIU Wei-dong. Enterococcus Faecalis LTA Activates NLRP3 Inflammasome by Promoting High Expression of ROS[J]. Journal of Oral Science Research, 2018, 34(2): 112-116.

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