Background and Objective
Although previous studies revealed the potential use of probiotics in the control of periodontitis, little is known about their interactions with gingival epithelial cells (GECs). Since GECs comprise the first defense in the subgingival microenvironment, the aim of this study was to evaluate the effect of probiotic lactobacilli and bifidobacteria strains on OBA‐9 cells challenged with Porphyromonas gingivalis.
Methods
Immortalized human GECs (OBA‐9) were challenged with live P. gingivalis (strains W83 and ATCC33277) and co‐infected with one of 12 tested probiotic strains at a multiplicity of infection (MOI) of 1:1000 for 2 hours. Bacterial adhesion and invasion were determined by antibiotic exclusion analysis and CFU counting. OBA‐9 viability was assessed by MTT assay, and levels of inflammatory mediators (TNF‐α, IL‐1β, and CXCL8) in the supernatants were determined by ELISA. The expression of genes encoding Toll‐like receptors (TLR2, TLR4) was evaluated by RT‐qPCR.
Results
Both strains of P. gingivalis were able to adhere and invade OBA‐9 cells, with significant loss in cell viability, increase in the levels of TNF‐α and IL‐1β, and upregulation of TLR4. However, co‐infection with probiotics attenuated these effects in P. gingivalis challenged GECs. Most probiotics maintained OBA‐9 viability and reduced pathogens adhesion and invasion. Furthermore, probiotics were able to adhere to GECs, which was enhanced for most strains in the presence of P. gingivalis. The synthesis of IL‐1β and TNF‐α by P. gingivalis in challenged GECs was reduced in co‐culture with most of the tested probiotics, whereas the secretion of CXCL8 increased, and TLR4 was downregulated.
Conclusion
Probiotics can alter the interaction of GECs with P. gingivalis by modulating the pathogen's ability to adhere and invade these cells, as well as by regulating the innate immune response. Such properties are strain‐specific and may indicate the most efficient probiotics to control periodontitis.
Although previous studies suggested an anti-inflammatory property of Brazilian red propolis (BRP), the mechanisms involved in the anti-inflammatory effects of BRP and its activity on macrophages were still not elucidated. This study aimed to evaluate whether BRP attenuates the inflammatory effect of LPS on macrophages and to investigate its underlying mechanisms. BRP was added to RAW 264.7 murine macrophages after activation with LPS. NO production, cell viability, cytokines profile were evaluated. Activation of inflammatory signaling pathways and macrophage polarization were determined by RT-qPCR and Western blot. BRP at 50 μg/ml inhibited NO production by 78% without affecting cell viability. Cd80 and Cd86 were upregulated whereas mrc1 was down regulated by BRP indicating macrophage polarization at M1. BRP attenuated the production of pro-inflammatory mediators IL-12, GM-CSF, IFN-Ɣ, IL-1β in cell supernatants although levels of TNF- α and IL-6 were slightly increased after BRP treatment. Levels of IL-4, IL-10 and TGF-β were also reduced by BRP. BRP significantly reduced the up-regulation promoted by LPS of transcription of genes in inflammatory signaling (Pdk1, Pak1, Nfkb1, Mtcp1, Gsk3b, Fos and Elk1) and of Il1β and Il1f9 (fold-change rate > 5), which were further confirmed by the inhibition of NF-κB and MAPK signaling pathways. Furthermore, the upstream adaptor MyD88 adaptor-like (Mal), also known as TIRAP, involved in TLR2 and TLR4 signaling, was down- regulated in BRP treated LPS-activated macrophages. Given that BRP inhibited multiple signaling pathways in macrophages involved in the inflammatory process activated by LPS, our data indicated that BRP is a noteworthy food-source for the discovery of new bioactive compounds and a potential candidate to attenuate exhacerbated inflammatory diseases.
Oral Diseases (2012) 18, 648–654
Aim: Infective agents may affect pregnancy outcomes by deregulating homeostasis.
Objectives: The effects of Porphyromonas gingivalis infection before and at different gestation periods were evaluated.
Materials and Methods: Wistar rats infected via subcutaneous with P. gingivalis W83, one week before mating (BM), days 1 (PR1) and 11 of gestation (PR11), and controls were evaluated, and samples were obtained at the end of gestation. P. gingivalis was detected by PCR. Cytokine was determined by ELISA.
Results: Infected rats had lower maternal gain of weight. Implantation was not observed in 2/12 BM rats. PR11 presented more fetal‐placental resorptions and lower placenta/fetus weight than controls. P. gingivalis was detected in placenta and fetus. IL‐6 and TNF‐α levels were higher in placenta and serum of infected groups, except for TNF‐α in placenta of PR1. IL‐1β levels were higher in placenta of PR11, but lower in serum and placenta of PR1. There were no differences in IL‐10 and PGE2 concentrations among the groups (P < 0.05).
Conclusions: The experimental infection by P. gingivalis resulted in alterations in the gestational pattern and in fetal development. The consequences of infection at mid‐gestation were more severe than at the beginning, possibly due to the induction of pro‐inflammatory cytokines in the fetal compartment.
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