Propiedades inflamatorias de Streptococcus dentisani sp. Un nuevo aliado contra las caries dentales?

BERÓN W; SASSO CV; ORTIZ FLORES RM

Mendoza

Congreso; XXXVI Científica Anual organizada por la Sociedad de Biología de Cuyo; 2018

Sociedad de Biología de Cuyo

The manifestation of dental caries is mediated by complex mechanisms that are initiated by genetic, behavioral, environmental and microbial factors. In the case of the latter, the presence of bacteria is essential for the onset and progression of caries lesions. It has been shown that some bacterial species predominate only in the initial stages of the lesion, while others are present exclusively in the advanced stages. Each caries lesion represents a unique ecosystem, where the microbial species form a biofilm. Regarding oral cavity microorganisms with dental caries, the main importance of Streptococcus mutans and related organisms has been established. However, Streptococcus species may constitute more than 50% of the oral microbiota in healthy individuals. In addition, they also have positive effects on human health, and some of them belonging to the Mitis group, have begun to be used as probiotics in disorders of the digestive system. Recently, Streptococcus dentisani has been isolated from caries-free human dental surfaces. This novel bacterium could be involved in the modulation and prevention of dental caries by inhibiting S. mutans by producing inhibitors of peptidic nature such as bacteriocin-like peptides, which makes it an ideal candidate as a probiotic agent for dental caries. However, there is little literature that identify different mechanisms of interaction of this bacterium with the individual and the protection against various pathogens from the oral cavity. Therefore, we propose to study the profile of interleukins produced by cell lines in response to infection with S. dentisani and S. mutans since they have a fundamental effect on the regulation of the mechanism of inflammation. The hypothesis of this work is that the presence of S. dentisani promotes the production of inflammatory interleukins in a cellular model in vitro. HeLa cells (human epithelial cells) were cultured in DMEM medium, with 10% fetal bovine serum. S. dentisani and S. mutans were inoculated into 50 ml of brain infusion broth and incubated aerobically at 37°C without stirring for 48 h. After growth, the culture was centrifuged at 3200 rpm for 10 min to separate the supernatant from the precipitate containing the bacteria. Culture cells were infected with bacterium or incubated with supernatant for 1 h, and then the cells were incubated at 37°C, 5% CO2 for different times. The samples were harvested in TRIzol reagent and processes to obtain DNA copy and polymerase chain reaction (PCR) assay. The data were analyzed by non-parametric Kolmogorov-Smirnov tests and parametric ANOVA in combination with the Tuckey and Dunnett test.