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Iranian Journal of Pharmaceutical... 2023Periodontitis is a chronic disease characterized by the inflammation of the periodontium and leads to progressive damage, such as gingival atrophy, alveolar bone loss,...
Evaluation of Antioxidant and Antibacterial Effects of Lyophilized Cell-Free Probiotic Supernatants of Three spp. and Their Cytocompatibility Against Periodontal Ligament Stem Cells.
BACKGROUND
Periodontitis is a chronic disease characterized by the inflammation of the periodontium and leads to progressive damage, such as gingival atrophy, alveolar bone loss, and tooth loss. and are bacteria that support the occurrence of periodontitis via the ability to form biofilms or damage the alveolar bone and periodontal ligaments. On the other hand, periodontal ligament stem cells (PDLSCs) are cells with differentiation capability into osteoblasts or osteoblasts. Due to their role in periodontal homeostasis and regeneration, PDLSCs are considered to control periodontitis progression. However, probiotics are helpful microorganisms known to have antimicrobial and immune-regulating effects.
OBJECTIVES
This study aimed to evaluate the antioxidant activity and antimicrobial effects of lyophilized cell-free supernatants (LCFSs) derived from three probiotic strains of on and . Moreover, the effect of these lyophilized supernatants was investigated on the viability and migration capability of PDLSCs.
METHODS
The antibacterial effects of LCFSs of three probiotic bacteria were investigated by determining the minimum inhibitory concentration and minimum bactericidal concentration. Then, the effect of LCFSs on the survival and migration of PDLSCs was investigated by the MTT method (at 24 and 72 hours) and scratch test (at 0, 24, and 48 hours), respectively. Finally, the antioxidant effect of LCFSs was assessed by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and ferric reducing/antioxidant power methods.
RESULTS
The antibacterial properties of different concentrations of acidic and neutral LCFSs derived from three studied probiotic bacteria on and were observed within the range of 12.5 - 50% (v/v) (1/8 - 1/2 dilutions with culture medium). Although there were no significant toxic (~ 100% viability) and wound healing effects on PDLSCs when the cells were exposed to either acidic or neutral studied LCFSs in a concentration of 5% (v/v), they showed significant antioxidant activity (~ 90% DPPH inhibition and 0.5 mM Fe/L).
CONCLUSIONS
The results revealed that 5% (v/v) 48-hour acidic and neutral supernatants of three studied probiotics might play a beneficial role in controlling periodontitis.
PubMed: 38116566
DOI: 10.5812/ijpr-136438 -
International Dental Journal Feb 2024The aim of this work was to explore the association between Aggregatibacter actinomycetemcomitans (A actinomycetemcomitans) infection and disease activity amongst those...
OBJECTIVE
The aim of this work was to explore the association between Aggregatibacter actinomycetemcomitans (A actinomycetemcomitans) infection and disease activity amongst those with rheumatoid arthritis (RA) with or without periodontitis (PD) in a Chinese population.
METHODS
A case-control study was conducted from November 2017 to March 2019. The correlation coefficients between A actinomycetemcomitans positivity and RA-related examination indicators as well as periodontal examination parameters were calculated by using the Spearman correlation analysis.
RESULTS
A total of 115 patients with RA were recruited: 67 patients with RA only and 48 with RA + PD. The percentage of A actinomycetemcomitans positivity was significantly higher in the RA + PD group compared with the RA-only group (P = .007 for positive percentage; P = .020 for percentage of A actinomycetemcomitans positivity in the total oral microbiome). Furthermore, RA-related measures such as Disease Activity Score 28, rheumatoid factor, anticyclic citrullinated peptide, and anticitrullinated protein antibodies were all positively correlated with the percentage of A actinomycetemcomitans positivity (P range: .002∼.041). In addition, significant correlations were observed amongst A actinomycetemcomitans positivity and probing pocket depth (P = .027) and gingival index (P = .043), whereas null correlations were found amongst the percentage of A actinomycetemcomitans positivity and plaque index (P = .344), clinical attachment loss (P = .217), and bleeding on probing (P = .710).
CONCLUSIONS
A actinomycetemcomitans infection may be related to the development of PD amongst patients with RA.
Topics: Humans; Aggregatibacter actinomycetemcomitans; Case-Control Studies; Periodontitis; Arthritis, Rheumatoid; Periodontal Attachment Loss
PubMed: 37517936
DOI: 10.1016/j.identj.2023.06.011 -
PLoS Pathogens Oct 2023Gram-negative bacteria derived extracellular vesicles (EVs), also known as outer membrane vesicles, have attracted significant attention due to their pathogenic roles in...
Gram-negative bacteria derived extracellular vesicles (EVs), also known as outer membrane vesicles, have attracted significant attention due to their pathogenic roles in various inflammatory diseases. We recently demonstrated that EVs secreted by the periodontopathogen Aggregatibacter actinomycetemcomitans (Aa) can cross the blood-brain barrier (BBB) and that their extracellular RNA cargo can promote the secretion of proinflammatory cytokines, such as IL-6 and TNF-α, in the brain. To gain more insight into the relationship between periodontal disease (PD) and neuroinflammatory diseases, we investigated the effect of Aa EVs in a mouse model of ligature-induced PD. When EVs were administered through intragingival injection or EV-soaked gel, proinflammatory cytokines were strongly induced in the brains of PD mice. The use of TLR (Toll-like receptor)-reporter cell lines and MyD88 knockout mice confirmed that the increased release of cytokines was triggered by Aa EVs via TLR4 and TLR8 signaling pathways and their downstream MyD88 pathway. Furthermore, the injection of EVs through the epidermis and gingiva resulted in the direct retrograde transfer of Aa EVs from axon terminals to the cell bodies of trigeminal ganglion (TG) neurons and the subsequent activation of TG neurons. We also found that the Aa EVs changed the action potential of TG neurons. These findings suggest that EVs derived from periodontopathogens such as Aa might be involved in pathogenic pathways for neuroinflammatory diseases, neuropathic pain, and other systemic inflammatory symptoms as a comorbidity of periodontitis.
Topics: Mice; Animals; Neuroinflammatory Diseases; Trigeminal Ganglion; Myeloid Differentiation Factor 88; Periodontitis; Periodontal Diseases; Blood-Brain Barrier; Cytokines; Mice, Knockout; Extracellular Vesicles
PubMed: 37871107
DOI: 10.1371/journal.ppat.1011743 -
Periodontology 2000 Jun 2023This review describes the origin and results of the prospective longitudinal study to test potential prognostic indicators for periodontal breakdown in a population... (Review)
Review
This review describes the origin and results of the prospective longitudinal study to test potential prognostic indicators for periodontal breakdown in a population deprived of regular dental care. Experimental gingivitis studies in individuals highly susceptible or highly resistant to periodontitis showed that bleeding on probing developed quite differently: 50% versus 18% bleeding, respectively, after 18 days of no oral hygiene. This formed, together with other clinical and microbiological parameters, the basis for the 15-year prospective study in the Java tea worker population to test potential prognostic indicators for periodontal breakdown. Evaluation showed that during the 15-year observation period of this population aged 15-25 years at baseline, the number of teeth decreased and the periodontal condition deteriorated. Gingival recession showed no increase during the first 7 years of observation, whereas a sixfold increase had occurred thereafter. Attachment loss doubled during the first 7 years, but almost tripled thereafter. Risk markers for disease onset/progression during the first 7 years of observation were age, the number of sites with subgingival calculus, and the subgingival presence of Aggregatibacter actinomycetemcomitans. Over the full period of 15 years the number of sites with a pocket depth of at least 5 mm and the number of sites with recession were identified as risk markers and male gender as a risk determinant. The prevalence of severe periodontitis amounted to 20% in 2002. Analysis showed that, already at baseline and throughout the study period, the periodontal condition in these individuals was more severe compared with the other participants. In conclusion, characteristics of susceptibility to periodontitis are already apparent in young adulthood.
PubMed: 37382474
DOI: 10.1111/prd.12497 -
Frontiers in Cellular and Infection... 2023Cytolethal distending toxins (Cdt) are a family of toxins produced by several human pathogens which infect mucocutaneous tissue and induce inflammatory disease. Human...
Cytolethal distending toxins (Cdt) are a family of toxins produced by several human pathogens which infect mucocutaneous tissue and induce inflammatory disease. Human macrophages exposed to () Cdt respond through canonical and non-canonical inflammasome activation to stimulate cytokine release. The inflammatory response is dependent on PI3K signaling blockade via the toxin's phosphatidylinositol-3,4,5-triphosphate (PIP3) phosphatase activity; converting PIP3 to phosphatidylinsoitol-3,4-diphosphate (PI3,4P2) thereby depleting PIP3 pools. Phosphoinositides, also play a critical role in phagosome trafficking, serving as binding domains for effector proteins during phagosome maturation and subsequent fusion with lysosomes. We now demonstrate that Cdt manipulates the phosphoinositide (PI) pools of phagosome membranes and alters Rab5 association. Exposure of macrophages to Cdt slowed phagosome maturation and decreased phago-lysosome formation, thereby compromising macrophage phagocytic function. Moreover, macrophages exposed to Cdt showed decreased bactericidal capacity leading to increase in survival. Thus, Cdt may contribute to increased susceptibility to bacterial infection. These studies uncover an underexplored aspect of Cdt function and provide new insight into the virulence potential of Cdt in mediating the pathogenesis of disease caused by Cdt-producing organisms such as
Topics: Humans; Aggregatibacter actinomycetemcomitans; Phosphatidylinositol 3-Kinases; Phagocytes; Macrophages; Phosphatidylinositols
PubMed: 37719670
DOI: 10.3389/fcimb.2023.1220089 -
Pathogens (Basel, Switzerland) May 2024Microbes frequently experience nutrient deprivations in the natural environment and may enter dormancy. is known to establish long-term infections in humans. This study...
Microbes frequently experience nutrient deprivations in the natural environment and may enter dormancy. is known to establish long-term infections in humans. This study examined the dormancy-like phenotype of an strain D7S-1 and its isogenic smooth-colony mutant D7SS. A tissue culture medium RPMI-1640 was nutrient-deficient (ND) and unable to support growth. RPMI-1640 amended with bases was nutrient-limited (NL) and supported limited growth of less than the nutrient-enriched (NE) laboratory medium did. Strain D7S-1, after an initial 2-log reduction in viability, maintained viability from day 4 to day 15 in the NL medium. Strain D7SS, after 1-log reduction in viability, maintained viability from day 3 to day 5. In contrast, bacteria in the NE medium were either non-recoverable (D7S-1; >6-log reduction) or continued to lose viability (D7SS; 3-log reduction) on day 5 and beyond. Scanning and transmission electron microscopy showed that in the NL medium formed robust biofilms similar to those in the NE medium but with evidence of stress. in the ND medium revealed scant biofilms and extensive cellular damage. We concluded that grown in the NL medium exhibited a dormancy-like phenotype characterized by minimum growth, prolonged viability, and distinct cellular morphology.
PubMed: 38787270
DOI: 10.3390/pathogens13050418 -
IScience Aug 2023The study investigates the interplay of neutrophils and natural-killer cells (NK) in mediating osseoresorption during infection of molar-incisor-pattern-periodontitis...
The study investigates the interplay of neutrophils and natural-killer cells (NK) in mediating osseoresorption during infection of molar-incisor-pattern-periodontitis (MIPP). Human neutrophils from periodontally healthy and MIPP patients were inoculated with the periopathogen (JP2) and their supernatants were exposed to NK to study their function and osteoclastogenesis promotion. A mouse MIPP model was used to compare disease progression following NK versus neutrophils depletion. The exposure of primary NK to supernatants of neutrophils inoculated with JP2 led to NK cell arrest and activation with enhanced osteoprotegerin expression. Incubation of monocytes with NK led to osteoclastogenesis, whereas NK that were pre-exposed to healthy neutrophil supernatant showed reduced osteoclastogenesis. In mice, NK depletion led to the similar bone phenotype as the neutrophil's depletion highlighting their role on osseoprotection. The present study portrays a key crosstalk between neutrophils and NK cells during JP2 infection as a central mechanism that regulates bone loss.
PubMed: 37588165
DOI: 10.1016/j.isci.2023.106430 -
Thoracic Cancer Apr 2024The causal relationship between breast cancer (BC) and the oral microbiome remains unclear. In this case-control study, using two-sample Mendelian randomization (MR), we...
BACKGROUND
The causal relationship between breast cancer (BC) and the oral microbiome remains unclear. In this case-control study, using two-sample Mendelian randomization (MR), we thoroughly explored the relationship between the oral microbiome and BC in the East Asian population.
METHODS
Genetic summary data related to oral microbiota and BC were collected from genome-wide association studies involving participants of East Asian descent. MR estimates were generated by conducting various analyses. Sequencing data from a case-control study were used to verify the validity of these findings.
RESULTS
MR analysis revealed that 30 tongue and 37 salivary bacterial species were significantly associated with BC. Interestingly, in both tongue and salivary microbiomes, we observed the causal effect of six genera, namely, Aggregatibacter, Streptococcus, Prevotella, Haemophilus, Lachnospiraceae, Oribacterium, and Solobacterium, on BC. Our case-control study findings suggest differences in specific bacteria between patients with BC and healthy controls. Moreover, sequencing data confirmed the MR analysis results, demonstrating that compared with the healthy control group, the BC group had a higher relative abundance of Pasteurellaceae and Streptococcaceae but a lower relative abundance of Bacteroidaceae.
CONCLUSIONS
Our MR analysis suggests that the oral microbiome exerts a causative effect on BC risk, supported by the sequencing data of a case-control study. In the future, studies should be undertaken to comprehensively understand the complex interaction mechanisms between the oral microbiota and BC.
Topics: Female; Humans; Breast Neoplasms; Case-Control Studies; East Asian People; Genome-Wide Association Study; Mendelian Randomization Analysis; Microbiota; Mouth
PubMed: 38485288
DOI: 10.1111/1759-7714.15280 -
Scientific Reports Apr 2024In multiple sclerosis (MS), alterations of the gut microbiota lead to inflammation. However, the role of other microbiomes in the body in MS has not been fully...
In multiple sclerosis (MS), alterations of the gut microbiota lead to inflammation. However, the role of other microbiomes in the body in MS has not been fully elucidated. In a pilot case-controlled study, we carried out simultaneous characterization of faecal and oral microbiota and conducted an in-depth analysis of bacterial alterations associated with MS. Using 16S rRNA sequencing and metabolic inference tools, we compared the oral/faecal microbiota and bacterial metabolism pathways in French MS patients (n = 14) and healthy volunteers (HV, n = 21). A classification model based on metabolite flux balance was established and validated in an independent German cohort (MS n = 12, HV n = 38). Our analysis revealed decreases in diversity indices and oral/faecal compartmentalization, the depletion of commensal bacteria (Aggregatibacter and Streptococcus in saliva and Coprobacter and Roseburia in faeces) and enrichment of inflammation-associated bacteria in MS patients (Leptotrichia and Fusobacterium in saliva and Enterobacteriaceae and Actinomyces in faeces). Several microbial pathways were also altered (the polyamine pathway and remodelling of bacterial surface antigens and energetic metabolism) while flux balance analysis revealed associated alterations in metabolite production in MS (nitrogen and nucleoside). Based on this analysis, we identified a specific oral metabolite signature in MS patients, that could discriminate MS patients from HV and rheumatoid arthritis patients. This signature allowed us to create and validate a discrimination model on an independent cohort, which reached a specificity of 92%. Overall, the oral and faecal microbiomes were altered in MS patients. This pilot study highlights the need to study the oral microbiota and oral health implications in patients with autoimmune diseases on a larger scale and suggests that knowledge of the salivary microbiome could help guide the identification of new pathogenic mechanisms associated with the microbiota in MS patients.
Topics: Humans; Multiple Sclerosis; Pilot Projects; RNA, Ribosomal, 16S; Microbiota; Bacteria; Inflammation
PubMed: 38565581
DOI: 10.1038/s41598-024-57949-4 -
Italian Journal of Pediatrics Oct 2023Periodontal disease and its bacteria can be responsible for pregnancy complications and transmission of periodontal bacteria from mother to newborn.
BACKGROUND
Periodontal disease and its bacteria can be responsible for pregnancy complications and transmission of periodontal bacteria from mother to newborn.
METHODS
A salivary swab to 60 healthy, full-term newborns and their mothers was taken immediately after birth. The test was performed with Real Time PCR method to evaluate the expression of the gene through DNA amplification. The species considered were: Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia and Fusobacterium nucleatum ssp.
RESULTS
The newborn oral microbiome was composed primarily by saprophytes (98.38 + 4.88%), just like the mothers (98.8 + 3.69%). There was a statistically significant difference of the total microbiological density in newborns and mothers (p = 0.0001). Maternal and neonatal oral microbiome had a correlated total microbiological density only in 33.3% (N = 20/60) of cases. The analysis of the oral microbiome showed a pathological composition only in 12/60 babies (20%). The most frequent detected specie in newborns was Fusobacterium nucleatum (9/12 babies, 75%), as well as for the mothers (53.3%). However, the pathogen was present both in baby and his mother only in 3 dyads. Porphyromonas gingivalis showed the highest association mother-baby (4/12 dyads, 33%). Porphyromonas gingivalis was the pathogen with the highest bacterial load in the 12 mothers. We found a statistically significant difference in the total load of Porphyromonas gingivalis in mothers and babies (p = 0.02).
CONCLUSIONS
There was a statistically significant difference in the richness of the microbiome from newborns and mothers. Even comparing the microbiological density in the oral cavity of the individual mother-child pairs, we did not find a significant concordance. These results seem to suggest a low influence of maternal oral microbiome on the richness of the oral neonatal one. We didn't find mother-child concordance (p = 0.0001) in the presence of pathogenic periodontal micro-organisms. Fusobacterium nucleatum was the most frequent specie detected. Porphyromonas gingivalis instead was the bacteria with the higher possibility of transmission. In conclusion in our study maternal oral health doesn't affect healthy, full-term newborns' oral microbiome. Further studies are needed to understand the maternal influence on newborn's oral microbiome and its effects on babies long-term health.
Topics: Infant; Pregnancy; Female; Infant, Newborn; Humans; Porphyromonas gingivalis; Prevotella intermedia; Fusobacterium nucleatum; Mothers
PubMed: 37840153
DOI: 10.1186/s13052-023-01520-w