In vitro modulation of proinflammatory and proteolytic activities of Porphyromonas gingivalis by selected lactobacilli.

OBJECTIVE: The aim of the present study was to characterize the antimicrobial and anti-inflammatory activities of postbiotics from lactic acid bacteria against Porphyromonas gingivalis. MATERIAL AND METHODS: The anti-P. gingivalis activity of postbiotics from the CERELA culture collection was assessed by measuring changes in the expression of key host proteins by ELISA and qPCR, the proteolytic activity by a fluorescence and a spectrophotometric method and virulence factors from P. gingivalis by qPCR. RESULTS: Even though Lacticaseibacillus (L.) rhamnosus CRL1522 and Lactiplantibacillus (L.) plantarum CRL1363 exhibit only a discrete antibacterial activity against P. gingivalis, the cell-free supernatants of these strains significantly reduced P. gingivalis-induced secretion of interleukins IL-6 and IL-8 by keratinocytes and TNF-α and IL-6 by U937 macrophage-like cells. More importantly, P. gingivalis arginine-gingipain (Rgp) protease activity was markedly reduced by both lactic acid bacteria (LAB) strains. This finding is particularly interesting because it means that both LAB might prevent the ulterior citrullination of peptides and the consequent generation of autoantibodies. The expression of COX2 and TLR2 was also significantly downregulated in macrophages. CONCLUSION: Postbiotics from L. rhamnosus CRL1522 and L. plantarum CRL1363 rise as suitable candidates for antagonizing the periodontopathogen P. gingivalis, since they were able to reduce the expression of proinflammatory cytokines and the protein degradation induced by this pathogen. We propose that postbiotics from these LAB could potentially halt the progression of periodontitis based on this in vitro study.