Insights from in vitro studies with probiotics and specialized pro-resolving mediators into new strategies in the control of periodontitis

Author(s)

Emmanuel Albuquerque de Souza

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Faculdade de Odontologia (FO/SDO)
• Defense date: 2019-09-12

Examining board members

Marinella Holzhausen Caldeira; Francisco Humberto Nociti Junior; Fernando Neves Nogueira

• Advisor: Marinella Holzhausen Caldeira; Marcia Pinto Alves Mayer

Abstract

The control of the periodontitis has been a challenge, especially in cases where the severe form is present. Considering the microbial and immunological etiologies of this disease, several strategies can be used to alter the dysbiotic related-microbiota and control the host immune response. In this context, the use of probiotics as well as specialized pro-resolving lipid mediators (SPMs) can be seen as promising alternatives in the control of this disease. However, in vitro studies should be carried out to better understand the mechanisms by which both alternatives can alter the micro-immunological profile of susceptibility associated with periodontitis, in order to modify the composition of the dysbiotic biofilm and to improve the regenerative activity in tissues lost for the uncontrolled inflammatory process. This thesis tried to evaluate both aspects. Firstly, we studied the interaction of several species of probiotics with gingival epithelial cells (GECs) challenged by Porphyromonas gingivalis strains in order to select those probiotics with greater potential in the control of this periodontopathogen as well as in the innate immune response mediated by this microorganism. In this sense, probiotics regulated the response mediated by GECs preventing cell death induced by P. gingivalis, reducing pathogen adhesion and invasion at the same time as they increase their own adhesion to GECs. The control of the interaction of GECs with P. gingivalis resulted in a reduction in the synthesis of IL-1? and TNF-? with concomitant increase in the release of CXCL8. Probiotics also altered the transcription of genes encoding pattern recogntition receptors, antimicrobial peptides and apoptosis regulatory genes, overall in a strain-specific manner. Secondly, we evaluated how SPMs (MaR1, RvE1) can alter the regenerative properties of human periodontal ligament stem cells (hPDLSCs) in an inflammatory environment (IL-1?, TNF-?), regarding biomarkers related to the formation of periodontal ligament, alveolar bone and cementum. The ratio of pro-inflammatory mediators and pro-resolving lipid mediators altered periodontal regenerative activities. A predominantly inflammatory environment under IL-1?/TNF-? stimulus reduced the stemness of hPDLSCs, downregulated the expression of their regenerative biomarkers, impaired their in vitro wound healing, and decreased their related cementum-osteogenic properties. However, the induction of an pro-resolving milue with the addition of MaR1/RvE1 reversed this process by partially rescuing biomarkers of stemness and ameliorate hPDLSCs regenerative-related activities. Therefore, an adequate control of the inflammatory environment was shown to be fundamental for an improvement in the process of tissue regeneration that must overcome the destruction of periodontal tissues. Thirdly, we formulate a hypothesis about how probiotics can help in the control of inflammation by regulating the synthesis of SPMs. (AU)

• FAPESP's process: 16/14687-6 - Evaluation of immunomodulatory potential of probiotics in periodontal disease
• Grantee: Emmanuel Albuquerque de Souza
• Support Opportunities: Scholarships in Brazil - Doctorate