The therapeutic effect of extracellular vesicles derived from Lactobacillus reuteri on periodontitis

REN Haozhe; WANG Ruoxin; FAN Siyuan; LIU Meng; XUAN Kun; WANG Jing

doi:10.15956/j.cnki.chin.j.conserv.dent.2025.11.002

Abstract：Objective This study aimed to investigate the therapeutic effect of extracellular vesicles derived from Lactobacillus reuteri(Lr-EVs)on periodontitis.Methods Lr-EVs were isolated from the culture supernatant of Lactobacillus reuteri using ultracentrifugation.The extracted vesicles were characterized by dynamic light scattering,transmission electron microscopy,and Coomassie blue staining.Experimental periodontitis in mouse model was established and the mouse were randomly divided into three groups:a healthy control group,a periodontitis model group,and a periodontitis model group treated with Lr-EVs.The treatment group started to be administered with Lr-EVs suspension via local periodontal tissue injection on the day of modeling,and samples were collected after 2 weeks.Alveolar bone resorption was quantified by Micro-CT analysis.Periodontal tissues was performed using hematoxylin-eosin staining and Masson staining to assess inflammatory infiltration and collagen fiber disruption.The protein expression levels of the M1 macrophage marker that inducible nitric oxide synthase(iNOS)and the proinflammatory cytokine interleukin-1β(IL-1β)in local periodontal tissues were detected by Western blotting.Results(1)Lr-EVs with a characteristic bilayer membrane structure were successfully isolated,exhibiting a peak particle size of approximately 124 nm.(2)Treatment with Lr-EVs significantly attenuated alveolar bone loss(P<0.01)and ameliorated pathological damage to the periodontal tissues.(3)Furthermore,Lr-EVs administration significantly downregulated the protein expression of iNOS and reduced the expression level of the proinflammatory cytokine IL-1β.Conclusion Lr-EVs effectively alleviate periodontal inflammation and alveolar bone resorption through inhibiting M1 macrophage polarization and reducing the secretion of proinflammatory factors.These findings suggest that Lr-EVs represent a promising novel therapeutic strategy for periodontitis.