In Vitro Preventive Effect and Mechanism of Action of Weissella cibaria CMU against Streptococcus mutans Biofilm Formation and Periodontal Pathogens

Abstract

In this study, we evaluated the in vitro anti-biofilm, antibacterial, and anti-inflammatory activity of Weissella cibaria CMU (CMU), an oral probiotic, against periodontopathogens. Compared to other oral probiotics, CMU showed a superior inhibitory effect on the biofilm formation and growth of Streptococcus mutans on orthodontic wires and artificial teeth (p < 0.05). CMU exerted potent antibacterial effects against S. mutans and Porphyromonas gingivalis according to a line test. In human gingival fibroblasts (HGFs) stimulated by P. gingivalis, Fusobacterium nucleatum, or Prevotella intermedia, CMU suppressed the gene expression of pro-inflammatory cytokines [interleukin (IL)-6, IL-1β, IL-8, and tumor necrosis factor-α] in a dose-dependent manner (p < 0.05). CMU restored the production of the tissue inhibitor of metalloproteinase-1 following its inhibition by P. gingivalis, and it suppressed the expression of matrix metalloproteinase (MMP)-1 and -3 induced by periodontopathogens (p < 0.05). Moreover, CMU needed direct contact with HGFs to exert their anti-inflammatory function, indicating that they act directly on gingival cells to modulate local inflammation. Our preclinical study provides evidence for the potential benefits of topical CMU treatments in preventing the development of caries and periodontitis caused by the dysbiosis of the dental plaque microbiome.

In Vitro Effects of Weissella cibaria CMU and CMS1 on Receptor Activator of NF-κB Ligand (RANKL)-Induced Osteoclast Differentiation

“…These experiments confirmed that HK-oraCMU and HK-oraCMS1 require direct interaction with osteoclast precursors to inhibit osteoclastogenesis. These results are consistent with those of a previous study in which live W. cibaria CMU showed an anti-inflammatory effect on human gingival fibroblasts through direct contact [ 22 ]. Similarly, metabolites demonstrated a tendency to reduce the expression of proteins associated with osteoclast differentiation, with high concentrations of CFS-oraCMS1 inducing a significant decrease, which is consistent with the findings on gene expression analysis ( Figure 8 ).…”

“…CFSs from the postbiotics Lactobacillus salivarius and Lactobacillus reuteri have considerable potential as functional oral health ingredients to inhibit alveolar bone loss associated with periodontitis [ 25 , 38 ]. Meanwhile, the W. cibaria CMU (oraCMU) and CMS1 (oraCMS1) strains have been commercialized as oral probiotics, and there has been ongoing research on their beneficial effects on oral health [ 18 , 19 , 20 , 21 , 22 ]. In particular, oraCMU was confirmed to suppress alveolar bone loss in a periodontitis-induced animal model; however, research on other associated inhibitory mechanisms in addition to its anti-inflammatory mechanism has not yet been conducted [ 18 ].…”

“…Given the crucial role of the oral microbiota in regulating alveolar bone remodeling [ 15 ], oral probiotics have been explored as a potential therapeutic intervention to maintain alveolar bone homeostasis and prevent periodontitis. Representative studies have been conducted employing various probiotics, including Bifidobacterium , Lactobacillus , and Weissella [ 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ].…”

“…Weissella cibaria strains CMU and CMS1 were isolated from the saliva of children with good oral health and Gram-positive lactic acid bacteria with a short rod-shaped morphology [ 19 ]. Both animal and clinical studies, including in vitro evaluations, indicate that these strains can inhibit the progression of periodontitis by regulating the inflammatory response of host cells [ 18 , 19 , 20 , 21 , 22 ]. Kim et al [ 18 ] demonstrated that bone loss in periodontitis-induced mice was prevented by treatment with the oral probiotic W. cibaria CMU, highlighting its capacity to reduce inflammatory cytokines in gum tissue.…”

“…Kim et al [ 18 ] demonstrated that bone loss in periodontitis-induced mice was prevented by treatment with the oral probiotic W. cibaria CMU, highlighting its capacity to reduce inflammatory cytokines in gum tissue. In addition, it has been proven that W. cibaria CMU inhibits the formation of pro-inflammatory cytokines in human gingival fibroblasts caused by periodontal disease-causing bacteria such as Fusobacterium nucleatum , Prevotella intermedia , and Porphyromonas gingivalis [ 22 ]. However, the effects of W. cibaria CMU and CMS1 on RANKL-induced osteoclast differentiation remain unexplored.…”