Abstract
BACKGROUND: Periodontitis, a chronic gum disease caused by Porphyromonas gingivalis infection, if left untreated, can result in tooth loss, alveolar bone loss, halitosis and other oral health complications. METHODS: To investigate the preventive and therapeutic effects of Lacticaseibacillus casei DS31 from the large yellow croaker (Larimichthys crocea) on periodontitis, three experimental models-biofilm, cellular, and animal models-were established to systematically evaluate its efficacy. First, we sought to clarify the effect of DS31 against P. gingivalis biofilm. Then, the investigation entailed a comprehensive examination of the immunomodulatory effects of heat-inactivated probiotics on inflammation-inducing cells. Finally, the impact of probiotics on gingival tissue and alveolar bone was evaluated using an established periodontitis rat model. RESULTS: The results demonstrated that bacteria suspension or cell-free supernatant of L. casei DS31 effectively inhibited P. gingivalis biofilm formation and eradicated existing biofilms, thereby reducing the secretion of pro-inflammatory cytokines (TNF-α, IL-6 and IL-1β) and inflammatory mediators (NO). Microcomputed tomography (micro-CT) and histopathological analysis revealed that supplementation with BS-DS31 or CFS-DS31 mitigated alveolar bone loss and increased bone mineral density in the experimental animals. The secretion of inflammatory factors (TNF-α, IL-1β, IL-6 and IL-8) in the gingival tissue of the rats was reduced. CONCLUSION: Lacticaseibacillus casei DS31 demonstrates significant potential for alleviating periodontitis and could serve as a promising probiotic candidate for incorporation into functional foods and oral health therapeutic applications.