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Brazilian Journal of Microbiology :... Mar 2022The present study aims to evaluate the antimicrobial property of Casiopeinas® copper- and ruthenium-based compounds against Aggregatibacter actinomycetemcomitans...
OBJECTIVES
The present study aims to evaluate the antimicrobial property of Casiopeinas® copper- and ruthenium-based compounds against Aggregatibacter actinomycetemcomitans serotype b (ATCC® 43,718™), as well as the cytotoxicity on an osteoblasts cell line of both compounds.
MATERIAL AND METHODS
The antibacterial effect of the copper-based compounds (CasII-gly, CasIII-ia) and the ruthenium-based compound (RuN-6) at four different concentrations was evaluated as the inhibition ratio of the bacterial growth after 48 h under anaerobic conditions, and the cell viability was measured through resazurin assay.
RESULTS
The copper- and ruthenium-based compounds used for this assay were (CasII-gly, CasIII-ia, and RuN-6), showing inhibitory activity between 39 and 62% compared to the antibiotic employed as control 66%. Cell viability was established between 61 and 96%.
CONCLUSIONS
Casiopeinas® and ruthenium showed dose and time dependent, inhibitory activity on A. actinomycetemcomitans, and low toxicity on cells (osteoblast) underexposure. The compound CasII-gly showed the best antimicrobial effect, and it could be considered a possible antimicrobial agent in periodontal therapy.
Topics: Aggregatibacter actinomycetemcomitans; Cell Survival; Copper; Osteoblasts; Ruthenium; Ruthenium Compounds
PubMed: 34741282
DOI: 10.1007/s42770-021-00648-3 -
Microbiology Spectrum Apr 2024and are two of the most common bacterial genera in the human oral cavity, encompassing both commensals and pathogens of substantial ecological and medical...
UNLABELLED
and are two of the most common bacterial genera in the human oral cavity, encompassing both commensals and pathogens of substantial ecological and medical significance. In this study, we conducted a metapangenomic analysis of oral and species to uncover genomic diversity, phylogenetic relationships, and habitat specialization within the human oral cavity. Using three metrics-pangenomic gene content, phylogenomics, and average nucleotide identity (ANI)-we first identified distinct species and sub-species groups among these genera. Mapping of metagenomic reads then revealed clear patterns of habitat specialization, such as species predominantly in dental plaque, a distinctive sub-species group on the tongue dorsum, and . sp. HMT-036 predominantly in keratinized gingiva and buccal mucosa. In addition, we found that supragingival plaque samples contained predominantly only one out of the three taxa, , , and . sp. HMT-458, suggesting independent niches or a competitive relationship. Functional analyses revealed the presence of key metabolic genes, such as oxaloacetate decarboxylase, correlated with habitat specialization, suggesting metabolic versatility as a driving force. Additionally, heme synthesis distinguishes . sp. HMT-036 from closely related , suggesting that the availability of micronutrients, particularly iron, was important in the evolutionary ecology of these species. Overall, our study exemplifies the power of metapangenomics to identify factors that may affect ecological interactions within microbial communities, including genomic diversity, habitat specialization, and metabolic versatility.
IMPORTANCE
Understanding the microbial ecology of the mouth is essential for comprehending human physiology. This study employs metapangenomics to reveal that various and species exhibit distinct ecological preferences within the oral cavity of healthy individuals, thereby supporting the site-specialist hypothesis. Additionally, it was observed that the gene pool of different species correlates with their ecological niches. These findings shed light on the significance of key metabolic functions in shaping microbial distribution patterns and interspecies interactions in the oral ecosystem.
Topics: Humans; Aggregatibacter; Phylogeny; Ecosystem; Haemophilus; Mouth
PubMed: 38488280
DOI: 10.1128/spectrum.04017-23 -
Clinical and Experimental Dental... Feb 2022Wiskott-Aldrich syndrome (WAS) is a rare X-linked primary immunodeficiency, characterized by micro-thrombocytopenia, recurrent infections, and eczema. This study aims to... (Review)
Review
OBJECTIVE
Wiskott-Aldrich syndrome (WAS) is a rare X-linked primary immunodeficiency, characterized by micro-thrombocytopenia, recurrent infections, and eczema. This study aims to describe common oral manifestations and evaluate oral microbioma of WAS patients.
MATERIAL AND METHODS
In this cohort study, 11 male WAS patients and 16 male healthy controls were evaluated in our Center between 2010 and 2018. Data about clinical history, oral examination, Gingival Index (GI) and Plaque Index (PI) were collected from both groups. Periodontal microbiological flora was evaluated on samples of the gingival sulcus.
RESULTS
WAS subjects presented with premature loss of deciduous and permanent teeth, inclusions, eruption disturbance, and significantly worse GI and PI. They also showed a trend toward a higher total bacterial load. Fusobacterium nucleatum, reported to contribute to periodontitis onset, was the most prevalent bacteria, together with Porphyromonas gingivalis and Tannerella forsythia.
CONCLUSIONS
Our data suggest that WAS patients are at greater risk of alterations in the oral cavity. The statistically higher incidence of periodontitis and the trend to higher prevalence of potentially pathological bacterial species in our small cohort, that should be confirmed in future in a larger population, underline the importance of dentistry monitoring as part of the multidisciplinary management of WAS patients.
Topics: Aggregatibacter actinomycetemcomitans; Child; Cohort Studies; Female; Humans; Male; Microbiota; Periodontitis; Prevotella intermedia; Wiskott-Aldrich Syndrome
PubMed: 35199474
DOI: 10.1002/cre2.503 -
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 -
Toxins Aug 2019is an oral pathogen that produces the RTX toxin, leukotoxin (LtxA; Leukothera). is strongly associated with the development of localized aggressive periodontitis. LtxA... (Review)
Review
is an oral pathogen that produces the RTX toxin, leukotoxin (LtxA; Leukothera). is strongly associated with the development of localized aggressive periodontitis. LtxA acts as a virulence factor for to subvert the host immune response by binding to the β integrin lymphocyte function-associated antigen-1 (LFA-1; CD11a/CD18) on white blood cells (WBCs), causing cell death. In this paper, we reviewed the state of knowledge on LtxA interaction with WBCs and the subsequent mechanisms of induced cell death. Finally, we touched on the potential therapeutic applications of LtxA (trade name Leukothera) toxin therapy for the treatment of hematological malignancies and immune-mediated diseases.
Topics: Aggregatibacter actinomycetemcomitans; Cell Membrane; Cell Survival; Endothelial Cells; Exotoxins; Hematologic Neoplasms; Humans; Immune System Diseases; Leukocytes; Lymphocyte Function-Associated Antigen-1; Mouth; Protein Binding; Virulence Factors
PubMed: 31454891
DOI: 10.3390/toxins11090489 -
International Journal of Molecular... Aug 2022Periodontal disease is a frequent pathology worldwide, with a constantly increasing prevalence. For the optimal management of periodontal disease, there is a need to... (Review)
Review
Periodontal disease is a frequent pathology worldwide, with a constantly increasing prevalence. For the optimal management of periodontal disease, there is a need to take advantage of actual technology to understand the bacterial etiology correlated with the pathogenic mechanisms, risk factors and treatment protocols. We analyzed the scientific literature published in the last 5 years regarding the recent applications of mRNA analysis in periodontal disease for the main known bacterial species considered to be the etiological agents: , and We identified new pathogenic mechanisms, therapeutic target genes and possible pathways to prevent periodontal disease. The mRNA analysis, as well as the important technological progress in recent years, supports its implementation in the routine management of periodontal disease patients.
Topics: Aggregatibacter actinomycetemcomitans; Humans; Periodontal Diseases; Porphyromonas gingivalis; RNA, Messenger; Tannerella forsythia; Treponema denticola
PubMed: 36077312
DOI: 10.3390/ijms23179915 -
Molecular Microbiology Jul 2011The mitis group streptococci (MGS) are widespread in the oral cavity and are traditionally associated with oral health. However, these organisms have many attributes... (Review)
Review
The mitis group streptococci (MGS) are widespread in the oral cavity and are traditionally associated with oral health. However, these organisms have many attributes that contribute to the development of pathogenic oral communities. MGS adhere rapidly to saliva-coated tooth surfaces, thereby providing an attachment substratum for more overtly pathogenic organisms such as Porphyromonas gingivalis, and the two species assemble into heterotypic communities. Close physical association facilitates physiologic support, and pathogens such as Aggregatibacter actinomycetemcomitans display resource partitioning to favour carbon sources generated by streptococcal metabolism. MGS exchange information with community members through a number of interspecies signalling systems including AI-2 and contact dependent mechanisms. Signal transduction systems induced in P. gingivalis are based on protein dephosphorylation mediated by the tyrosine phosphatase Ltp1, and converge on a LuxR-family transcriptional regulator, CdhR. Phenotypic responses in P. gingivalis include regulation of hemin uptake systems and gingipain activity, processes that are intimately linked to the virulence of the organism. Furthermore, communities of S. gordonii with P. gingivalis or with A. actinomycetemcomitans are more pathogenic in animal models than the constituent species alone. We propose that MGS should be considered accessory pathogens, organisms whose pathogenic potential only becomes evident in the context of a heterotypic microbial community.
Topics: Aggregatibacter actinomycetemcomitans; Carrier State; Humans; Microbial Interactions; Mouth; Porphyromonas gingivalis; Signal Transduction; Streptococcal Infections; Viridans Streptococci
PubMed: 21635580
DOI: 10.1111/j.1365-2958.2011.07707.x -
Molecular Oral Microbiology Jun 2020Aggregatibacter actinomycetemcomitans is a Gram-negative bacterium associated with localized aggressive periodontitis, as well as other systemic diseases. This organism... (Review)
Review
Aggregatibacter actinomycetemcomitans is a Gram-negative bacterium associated with localized aggressive periodontitis, as well as other systemic diseases. This organism produces a number of virulence factors, all of which provide some advantage to the bacterium. Several studies have demonstrated that clinical isolates from diseased patients, particularly those of African descent, frequently belong to specific clones of A. actinomycetemcomitans that produce significantly higher amounts of a protein exotoxin belonging to the repeats-in-toxin (RTX) family, leukotoxin (LtxA), whereas isolates from healthy patients harbor minimally leukotoxic strains. This finding suggests that LtxA might play a key role in A. actinomycetemcomitans pathogenicity. Because of this correlation, much work over the past 30 years has been focused on understanding the mechanisms by which LtxA interacts with and kills host cells. In this article, we review those findings, highlight the remaining open questions, and demonstrate how knowledge of these mechanisms, particularly the toxin's interactions with lymphocyte function-associated antigen-1 (LFA-1) and cholesterol, enables the design of targeted anti-LtxA strategies to prevent/treat disease.
Topics: Aggregatibacter actinomycetemcomitans; Exotoxins; Humans; Lymphocyte Function-Associated Antigen-1; Virulence Factors
PubMed: 32061022
DOI: 10.1111/omi.12284 -
PloS One 2021Periodontitis can result in tooth loss and the associated chronic inflammation can provoke several severe systemic health risks. Adjunctive to mechanical treatment of...
Periodontitis can result in tooth loss and the associated chronic inflammation can provoke several severe systemic health risks. Adjunctive to mechanical treatment of periodontitis and as alternatives to antibiotics, the use of probiotic bacteria was suggested. In this study, the inhibitory effect of the probiotic Streptococcus salivarius subsp. salivarius strains M18 and K12, Streptococcus oralis subsp. dentisani 7746, and Lactobacillus reuteri ATCC PTA 5289 on anaerobic periodontal bacteria and Aggregatibacter actinomycetemcomitans was tested. Rarely included in other studies, we also quantified the inverse effect of pathogens on probiotic growth. Probiotics and periodontal pathogens were co-incubated anaerobically in a mixture of autoclaved saliva and brain heart infusion broth. The resulting genome numbers of the pathogens and of the probiotics were measured by quantitative real-time PCR. Mixtures of the streptococcal probiotics were also used to determine their synergistic, additive, or antagonistic effects. The overall best inhibitor of the periodontal pathogens was L. reuteri ATCC PTA 5289, but the effect is coenzyme B12-, anaerobiosis-, as well as glycerol-dependent, and further modulated by L. reuteri strain DSM 17938. Notably, in absence of glycerol, the pathogen-inhibitory effect could even turn into a growth spurt. Among the streptococci tested, S. salivarius M18 had the most constant inhibitory potential against all pathogens, followed by K12 and S. dentisani 7746, with the latter still having significant inhibitory effects on P. intermedia and A. actinomycetemcomitans. Overall, mixtures of the streptococcal probiotics did inhibit the growth of the pathogens equally or-in the case of A. actinomycetemcomitans- better than the individual strains. P. gingivalis and F. nucleatum were best inhibited by pure cultures of S. salivarius K12 or S. salivarius M18, respectively. Testing inverse effects, the growth of S. salivarius M18 was enhanced when incubated with the periodontal pathogens minus/plus other probiotics. In contrast, S. oralis subsp. dentisani 7746 was not much influenced by the pathogens. Instead, it was significantly inhibited by the presence of other streptococcal probiotics. In conclusion, despite some natural limits such as persistence, the full potential for probiotic treatment is by far not utilized yet. Especially, further exploring concerted activity by combining synergistic strains, together with the application of oral prebiotics and essential supplements and conditions, is mandatory.
Topics: Aggregatibacter actinomycetemcomitans; Anaerobiosis; Antibiosis; Humans; Limosilactobacillus reuteri; Periodontitis; Porphyromonas gingivalis; Probiotics; Saliva; Streptococcus; Streptococcus mutans; Streptococcus salivarius
PubMed: 33667279
DOI: 10.1371/journal.pone.0248308 -
BMC Oral Health May 2021Periodontal disease represents a major health concern. The administration of beneficial microbes has been increasing in popularity over efforts to manipulate the...
BACKGROUND
Periodontal disease represents a major health concern. The administration of beneficial microbes has been increasing in popularity over efforts to manipulate the microbes using antimicrobial agents. This study determined the ability of Streptococcus salivarius to inhibit IL-6 and IL-8 production by gingival fibroblasts when activated by periodontal pathogens and their effect on the salivary microbiome.
METHODS
Primary human gingival fibroblasts were challenged with Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans and Fusobacterium nucleatum and a combination of all three. IL-6 and IL-8 cytokine release were measured. Using this same model, S. salivarius K12, M18 and different supernatant and whole-cell lysate fractions of S. salivarius K12 were administered to pathogen-induced fibroblasts. A patient study of healthy participants was also conducted to determine the effect S. salivarius K12 had on the native microbiome using 16S next generation sequence analysis.
RESULTS
All pathogens tested induced a significant IL-6 and IL-8 response. S. salivarius K12 or M18, did not exhibit an increase in inflammatory cytokines. When either of the probiotic strains were co-administered with a pathogen, there were significant reductions in both IL-6 and IL-8 release. This effect was also observed when gingival fibroblasts were pre-treated with either S. salivarius K12 or M18 and then stimulated with the oral pathogens. Chewing gum containing S. salivarius K12 did not alter the salivary microbiome and did not increase inflammatory markers in the oral cavity.
CONCLUSION
S. salivarius K12 and M18 prevented immune activation induced by periodontal disease pathogens. S. salivarius K12 did not alter the salivary microbiome or induce immune activation when administered as a chewing gum. These results warrant further study to determine if it may be an effective treatment in a model of periodontal disease.
Topics: Aggregatibacter actinomycetemcomitans; Fusobacterium nucleatum; Humans; Periodontal Diseases; Porphyromonas gingivalis; Streptococcus salivarius
PubMed: 33962608
DOI: 10.1186/s12903-021-01606-z