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| Author(s): |
Amália Cristina de Souza Cataruci
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Faculdade de Odontologia (FO/SDO) |
| Defense date: | 2020-03-06 |
| Examining board members: |
Marcia Pinto Alves Mayer;
Joni Augusto Cirelli;
Atlas Edson Moleros Nakamae;
Claudio Mendes Pannuti
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| Advisor: | Marcia Pinto Alves Mayer |
| Abstract | |
The use of probiotics in health is widely known, but the mechanisms involved in the control of inflammatory diseases, such as periodontitis, are still poorly explored. Probiotic bacteria may promote modulation of the mucosal and systemic immune response under health or disease conditions. Previous in vitro studies from our laboratory revealed that probiotics of the genus Lactobacillus are capable of interfering in the formation of the multispecies biofilm formed by Porphyromonas gingivalis and Streptococcus species, as well as interfering in the adhesion and invasion processes in epithelial cells and in the response of these cells to the periodontal pathogen. The present study aimed to determine the ability of two probiotic strains of the genus Lactobacillus (L. acidophilus LA5 and L. rhamnosus LR32) to control the destruction of periodontal tissues in murine model assays. Probiotic strains were tested in an animal model of experimental periodontitis induced by oral polymicrobial infection (P. gingivalis W83 e ATCC 33277, P. intermedia 17, F. nucleatum ATCC 25586 e S. gordonii DL-1) in C57BL/6 mice. The animals were divided into six groups composed of eight animals each, submitted to different treatments by oral inoculation: 2% carboxymethylcellulose vehicle (SHAM or P-L-), microbial consortium (P+L-), probiotic L. acidophilus LA5 [P-L+(LA5)], L. acidophilus LA5 probiotic concurrent with the microbial consortium [P+L+(LA5)], L. rhamnosus LR32 probiotic [P-L+(LR32)] and L. rhamnosus LR32 probiotic concurrent with the microbial consortium [P+L+(LR32)]. After the 45-day experimental period, euthanasia was performed for further analysis of alveolar bone loss by microCT, expression of genes encoding intra and extracellular receptors and cytokines by RT-qPCR in the gingival tissues, levels of IL-1, TNF-, IL- 6, IL-8, IL-17, IL-4 and IL-10 in the gingival tissues, in addition to the weight gain of the animals. The experimental periodontitis model employed was successful, with reduction of bone volume in the group under induction of periodontal disease (P+L-). The probiotic strains tested seem to be able to prevent alveolar bone loss in the experimental animals, with bone volume of the P+L+(LA5) and P+L+(LR32) groups similar to that observed in the SHAM group. No statistically significant differences were observed in the expression of genes encoding the pro-inflammatory cytokines il-1, tnf-, il-6 and il-18 in the gingival tissue of animals under induction of periodontal disease; however, the L. rhamnosus LR32 strain appears to lead to a higher expression of il-1 and tnf-, and further induced positive regulation of tlr4 expression in the presence and absence of microbial consortium [P+L+(LR32) and P-L+(LR32)] in relation to the positive control, P+L-.The evaluation of cytokine levels in gingival tissue revealed that the microbial consortium induced higher levels of IL-6 in gingival tissue (P+L-group) than SHAM group and those receiving probiotics, with or without microbial consortium. On the other hand, the microbial consortium (P+L-) did not induce the increase of the levels of other inflammatory mediators (IL-1, TNF- and IL-17) in relation to SHAM. However, increased levels of IL-1, but also of IL-4 and IL- 10, were observed in the P+L+(LA5) gingival tissue when compared to the SHAM and P+L- groups. In addition, probiotic L. rhamnosus LR32 also induced higher levels of IL-10 [P-L+(LR32)], but this effect was partially reduced by the addition of microbial consortium [P+L+(LR32)]. The administration of the microbial consortium did not lead to changes in animal weight gain (P+L- compared to SHAM), but significantly higher weight gain was observed in the P+L+(LR32) group when compared to the P+L+(LA5) group. Thus, considering the limitations of the study and the need for further investigation, the data obtained indicate that the probiotic strains tested have potential for the prevention and control of periodontal disease. (AU) | |
| FAPESP's process: | 18/02318-1 - Effect of probiotic lactobacilli on the modulation of inflammassome and alveolar bone loss promoted by experimental periodontitis in healthy mice |
| Grantee: | Amália Cristina de Souza Cataruci |
| Support Opportunities: | Scholarships in Brazil - Master |