anti-inflammatory and antibiofilm activities of bacterial lysates from lactobacilli against oral pathogenic bacteria.

Postbiotics are functional biological compounds, such as bacterial lysates (BLs) released from probiotic bacteria. Although postbiotics exert various bioactivities, the anti-inflammatory and antibiofilm activities of BLs against oral pathogenic bacteria have not been investigated. In the present study, pretreatment with BLs extracted from and GG suppressed the mRNA and protein expression levels of inflammatory mediators induced by the lipopolysaccharide (LPS) of in RAW 264.7 cells. Both BLs attenuated LPS-induced phosphorylation of mitogen-activated protein kinases (MAPKs) and activation of nuclear factor-κB (NF-κB), suggesting that BLs inhibit periodontal inflammatory responses by regulating the MAPK and NF-κB signaling pathways. Moreover, both BLs interfered with biofilm formation by ; however, they did not eradicate the established biofilm. Furthermore, both BLs downregulated B, C, and D responsible for biofilm formation by , suggesting that BLs reduce the synthesis of extracellular polysaccharide and thereby reduce biofilm. Taken together, these results suggest that BLs of and GG can attenuate periodontal inflammation and dental caries and thus contribute to the improvement of oral health.