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Journal of Dental Research Jul 2023Subclinical hypothyroidism (SCH) has been shown to be associated with microbiota. However, the association between SCH and oral microbiota has not yet been elucidated....
Subclinical hypothyroidism (SCH) has been shown to be associated with microbiota. However, the association between SCH and oral microbiota has not yet been elucidated. The results of our previous clinical studies showed that was abundant in the oral microbiota of SCH patients. This study aimed to investigate the relationship between SCH and oral microbiota, verify the pathogenicity of in SCH, and preliminarily explore the possible mechanism. The SCH mouse model with oral application of was established, and the variance in the mouse oral microbiota and changes in thyroid function and metabolism were detected in mice. Student's test and analysis of variance were used for statistical analysis. Oral application of changed the composition of the oral microbiota of SCH mice, which enhanced the damage to the thyroid and decreased the expression of functional genes of the thyroid. Moreover, decreased oxygen consumption and aggravated glucose and lipid metabolism disorders in SCH mice. Glucose tolerance and insulin tolerance decreased, and the triglyceride content of the liver and inflammatory infiltration in adipose tissue increased in SCH mice after stimulation. Mechanistically, increased the proportion of CD4 T cells in cervical lymph nodes and thyroids in SCH mice. Th1 cells were suggested to play an important role in the pathogenesis of SCH involving . In conclusion, aggravated SCH manifestations, including thyroid dysfunction and glucose and lipid metabolism disorders, by causing immune imbalance in mice. This study sheds new light on the pathogenesis of SCH from the perspective of oral microbiota.
Topics: Mice; Animals; Prevotella intermedia; Hypothyroidism; Lipid Metabolism Disorders; Glucose
PubMed: 37204148
DOI: 10.1177/00220345231168052 -
Journal of Periodontology Jan 2020Periodontitis, an inflammatory disease of multibacterial etiology that affects the protective and supporting tissues surrounding teeth, can influence the course of...
BACKGROUND
Periodontitis, an inflammatory disease of multibacterial etiology that affects the protective and supporting tissues surrounding teeth, can influence the course of respiratory diseases, such as asthma, due to epithelial alterations arising from inflammatory and immunological processes, bronchial remodeling, or by the aspiration of pathogenic colonizers found in periodontal pockets. This study evaluated the levels of periodontal pathogens Prevotella intermedia, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Aggregatibacter actinomycetemcomitans in the subgingival biofilm of individuals with and without severe asthma.
METHODS
A case-control study enrolling 457 individuals (220 with asthma and 237 without asthma) was conducted at the Program for Control of Asthma in Bahia (ProAR) Clinic located in Salvador, Bahia, Brazil. A structured questionnaire was used to obtain data on sociodemographic, health status, and lifestyle habits. A clinical periodontal assessment was performed, including bleeding on probing, probing depth, and clinical attachment level. Subgingival biofilm was collected at the deepest site of each sextant, and bacterial DNA was extracted. Quantitative real-time PCR analysis was performed to detect and relatively quantify periodontopathogens in the biofilm.
RESULTS
Statistically significant positive associations were found between periodontitis and severe asthma, (odds ratio [OR] : 4.00; 95% confidence interval [CI]: 2.26 to 7.10). High levels of P. intermedia were found in association with the presence of severe asthma (OR : 2.64; 95% CI: 1.62 to 4.39; P < 0.01).
CONCLUSIONS
The present results suggest that periodontitis and P. intermedia are associated with severe asthma. However, the functional consequences of this dysbiosis upon asthma susceptibility and its phenotypes remain unclear.
Topics: Aggregatibacter actinomycetemcomitans; Asthma; Bacteroides; Brazil; Case-Control Studies; Humans; Periodontitis; Porphyromonas gingivalis; Prevotella intermedia; Treponema denticola
PubMed: 31342509
DOI: 10.1002/JPER.19-0065 -
Internal Medicine Journal May 2022
Topics: Arthritis, Infectious; Humans; Knee Joint; Osteomyelitis; Prevotella intermedia
PubMed: 35538015
DOI: 10.1111/imj.15784 -
Periodontology 2000 Jun 2020Atherosclerosis is central to the pathology of cardiovascular diseases, a group of diseases in which arteries become occluded with atheromas that may rupture, leading to... (Review)
Review
Atherosclerosis is central to the pathology of cardiovascular diseases, a group of diseases in which arteries become occluded with atheromas that may rupture, leading to different cardiovascular events, such as myocardial infarction or ischemic stroke. There is a large body of epidemiologic and animal model evidence associating periodontitis with atherosclerotic disease, and many potential mechanisms linking these diseases have been elucidated. This chapter will update knowledge on these mechanisms, which generally fall into 2 categories: microbial invasion and infection of atheromas; and inflammatory and immunologic. With respect to the invasion and infection of atheromas, it is well established that organisms from the subgingival biofilm can enter the circulation and lodge in most distant tissues. Bacteremias resulting from oral interventions, and even oral hygiene activities, are well documented. More recently, indirect routes of entry of oral organisms (via phagocytes or dendritic cells) have been described for many oral organisms, into many tissues. Such organisms include the periodontal pathogens Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Tannerella forsythia, and Fusobacterium nucleatum. Intracellular survival of these organisms with dissemination to distant sites (The Trojan Horse approach) has been described. Their relative contribution to atheroma formation and progression has been studied mainly in experimental research, with results demonstrating that these organisms can invade endothelial cells and phagocytic cells within the atheroma, leading to pathogenic changes and progression of the atheroma lesion. The second category of mechanisms potentially linking periodontitis to atherosclerosis includes the dumping of inflammatory mediators originating from periodontal lesions into the systemic circulation. These inflammatory mediators, such as C-reactive protein, matrix metalloproteinases, fibrinogen, and other hemostatic factors, would further accelerate atheroma formation and progression, mainly through oxidative stress and inflammatory dysfunction. Moreover, direct effects on lipid oxidation have also been described. In summary, the evidence supports the concept that periodontitis enhances the levels of systemic mediators of inflammation that are risk factors for atherosclerotic diseases.
Topics: Aggregatibacter actinomycetemcomitans; Atherosclerosis; Endothelial Cells; Humans; Periodontitis; Porphyromonas gingivalis; Prevotella intermedia
PubMed: 32385879
DOI: 10.1111/prd.12304 -
The Biochemical Journal Jan 2020As part of the infective process, Porphyromonas gingivalis must acquire heme which is indispensable for life and enables the microorganism to survive and multiply at the...
As part of the infective process, Porphyromonas gingivalis must acquire heme which is indispensable for life and enables the microorganism to survive and multiply at the infection site. This oral pathogenic bacterium uses a newly discovered novel hmu heme uptake system with a leading role played by the HmuY hemophore-like protein, responsible for acquiring heme and increasing virulence of this periodontopathogen. We demonstrated that Prevotella intermedia produces two HmuY homologs, termed PinO and PinA. Both proteins were produced at higher mRNA and protein levels when the bacterium grew under low-iron/heme conditions. PinO and PinA bound heme, but preferentially under reducing conditions, and in a manner different from that of the P. gingivalis HmuY. The analysis of the three-dimensional structures confirmed differences between apo-PinO and apo-HmuY, mainly in the fold forming the heme-binding pocket. Instead of two histidine residues coordinating heme iron in P. gingivalis HmuY, PinO and PinA could use one methionine residue to fulfill this function, with potential support of additional methionine residue/s. The P. intermedia proteins sequestered heme only from the host albumin-heme complex under reducing conditions. Our findings suggest that HmuY-like family might comprise proteins subjected during evolution to significant diversification, resulting in different heme coordination modes. The newer data presented in this manuscript on HmuY homologs produced by P. intermedia sheds more light on the novel mechanism of heme uptake, could be helpful in discovering their biological function, and in developing novel therapeutic approaches.
Topics: Gene Expression Regulation, Bacterial; Heme; Hemeproteins; Humans; Iron; Periodontitis; Porphyromonas gingivalis; Prevotella intermedia; RNA, Messenger; Sequence Homology, Amino Acid
PubMed: 31899475
DOI: 10.1042/BCJ20190607 -
Virulence Dec 2022readily colonizes healthy dental biofilm and is associated with periodontal diseases. The viscous exopolysaccharide (EPS)-producing capability is known as a major...
readily colonizes healthy dental biofilm and is associated with periodontal diseases. The viscous exopolysaccharide (EPS)-producing capability is known as a major virulence factor of 17 (Pi17). However, the inter-strain difference in regarding virulence-associated phenotype is not well studied. We compared virulence and whole genome sequences using five wild-type strains: ATCC 49046 (Pi49046), ATCC 15032 (Pi15032), ATCC 15033 (Pi15033), ATCC 25611 (Pi25611), and Pi17. Non-EPS producing Pi25611 was the least virulent in insect and mammalian models. Unexpectedly, Pi49046 did not produce viscous EPS but was the most virulent, followed by Pi17. Genomes of the five strains were quite similar but revealed subtle differences such as copy number variations and single nucleotide polymorphisms. Variations between strains were found in genes encoding glycosyltransferases and genes involved in the acquisition of carbohydrates and iron/haem. Based on these genetic variations, further analyses were performed. Phylogenetic and structural analyses discovered phosphoglycosyltransferases of Pi49046 and Pi17 have evolved to contain additional loops that may confer substrate specificity. Pi17, Pi15032, and Pi15033 displayed increased growth by various carbohydrates. Meanwhile, Pi49046 exhibited the highest activities for haemolysis and haem accumulation, as well as co-aggregation with harbouring type II, which is more tied to periodontitis than other types. Collectively, subtle genetic differences related to glycosylation and acquisition of carbohydrates and iron/haem may contribute to the diversity of virulence and phenotypic traits among strains. These variations may also reflect versatile strategies for within-host adaptation of
Topics: Animals; Carbohydrates; DNA Copy Number Variations; Genomics; Heme; Iron; Mammals; Phylogeny; Prevotella intermedia; Virulence
PubMed: 35791444
DOI: 10.1080/21505594.2022.2095718 -
Nutrition Research (New York, N.Y.) Oct 2022The hypothesis of the present study was that nitro-fatty acids (NO-FAs) would suppress inflammation associated with periodontal disease. To test this hypothesis, we...
The hypothesis of the present study was that nitro-fatty acids (NO-FAs) would suppress inflammation associated with periodontal disease. To test this hypothesis, we investigated the influence of nitrooleic acid, a prototypical NO-FA, on the inflammatory response of murine macrophages activated with lipopolysaccharide (LPS) from Prevotella intermedia, a pathogen associated the etiology of different types of periodontal diseases. LPS was prepared from P. intermedia cells by using phenol-water protocol. Culture supernatants were assayed for nitric oxide (NO), interleukin-1β (IL-1β), and IL-6. Real-time polymerase chain reaction and immunoblotting analyses were performed to quantify messenger RNA and protein expression, respectively. The secreted embryonic alkaline phosphatase reporter assay was performed to measure NF-κB activation. The transcription factor assay kit was used to measure DNA-binding of NF-κB subunits. Findings obtained from the present study revealed that nitrooleic acid suppresses the generation and messenger RNA expression of inducible NO synthase-derived NO, IL-1β, and IL-6 in RAW264.7 cells activated with P. intermedia LPS and promotes macrophage polarization toward anti-inflammatory M2 phenotype. We also found that nitrooleic acid exerts its effect via heme oxygenase-1 induction and suppression of NF-κB signaling. The inhibition of NO and proinflammatory cytokine production by nitrooleic acid was independent from PPAR-γ, JNK, p38, and STAT1/3. Nitrooleic acid may represent a novel class of agent as a host modulator which has therapeutic benefit in periodontal disease, though more work is needed to confirm this.
Topics: Alkaline Phosphatase; Animals; Anti-Inflammatory Agents; DNA; Fatty Acids; Heme Oxygenase-1; Interleukin-1beta; Interleukin-6; Lipopolysaccharides; Macrophage Activation; Mice; NF-kappa B; Nitric Oxide; Nitric Oxide Synthase Type II; Nitrogen Dioxide; Periodontal Diseases; Peroxisome Proliferator-Activated Receptors; Phenols; Prevotella intermedia; RNA, Messenger; Water
PubMed: 36126528
DOI: 10.1016/j.nutres.2022.07.009 -
Anaerobe Dec 2018The accuracy of a phenotypic scheme to recognize periodontal Prevotella intermedia/nigrescens group clinical isolates on primary isolation culture plates was assessed...
The accuracy of a phenotypic scheme to recognize periodontal Prevotella intermedia/nigrescens group clinical isolates on primary isolation culture plates was assessed with matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS). A total of 84 fresh subgingival isolates from 23 chronic periodontitis patients were presumptively recognized on anaerobically-incubated enriched Brucella blood agar primary isolation plates as P. intermedia/nigrescens based on their dark-pigmented colony morphology, brick-red autofluorescence under long-wave ultraviolet light, and a negative fluorescence test for lactose production. The presumptive P. intermedia/nigrescens clinical isolates were subjected to MALDI-TOF MS analysis using Bruker MALDI Biotyper analytic software containing mass spectra for P. intermedia and Prevotella nigrescens in its reference library of bacterial protein profiles. Using a ≥1.7 log score agreement threshold, 60 (71.4%) of the presumptive P. intermedia/nigrescens clinical isolates were confirmed as either P. intermedia (25 isolates) or P. nigrescens (35 isolates). All isolates with a <1.7 log score were also identified as P. intermedia or P. nigrescens from the top choice designated on the MALDI Biotyper most likely species identification list. These MALDI-TOF MS findings document the ability of the phenotypic scheme to correctly recognize most periodontal P. intermedia/nigrescens group clinical isolates on primary isolation culture plates.
Topics: Adult; Bacterial Typing Techniques; Bacteroidaceae Infections; Chronic Periodontitis; Female; Humans; Male; Phenotype; Prevotella intermedia; Prevotella nigrescens; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 29913204
DOI: 10.1016/j.anaerobe.2018.06.007 -
Lasers in Surgery and Medicine Oct 2016Selective killing of pathogens by laser is possible due to the difference in absorption of photon energy by pathogens and host tissues. The optical properties of...
BACKGROUND AND OBJECTIVE
Selective killing of pathogens by laser is possible due to the difference in absorption of photon energy by pathogens and host tissues. The optical properties of pathogenic microorganisms are used along with the known optical properties of soft tissues in calculations of the laser-induced thermal response of pathogen colonies embedded in a tissue model. The objective is to define the laser parameters that optimize pathogen destruction and depth of the bactericidal effect.
MATERIALS AND METHODS
The virtual periodontium is a computational model of the optical and time-dependent thermal properties of infected periodontal tissues. The model simulates the periodontal procedure: Laser Sulcular Debridement. Virtual pathogen colonies are placed at different depths in the virtual periodontium to determine the depth for effective bactericidal effects given various laser parameters (wavelength, peak power, pulse duration, scan rate, fluence rate) and differences in pathogen sensitivities.
RESULTS
Accumulated background heat from multiple passes increases the depth of the bactericidal effect. In visible and near-IR wavelengths the large difference in absorption between normal soft tissue and Porphyromonas gingivalis (Pg) and Prevotella intermedia (Pi) results in selective destruction. Diode laser (810 nm) efficacy and depth of the bactericidal effect are variable and dependent on hemin availability. Both pulsed-Nd:YAG and the 810 nm diode lasers achieve a 2-3 mm deep damage zone for pigmented Pg and Pi in soft tissue without surface damage (selective photoantisepsis). The model predicts no selectivity for the Er:YAG laser (2,940 nm). Depth of the bactericidal effect is highly dependent on pathogen absorption coefficient. Highly sensitive pathogens may be destroyed as deep as 5-6 mm in soft tissue. Short pulse durations enable confinement of the thermal event to the target. Temporal selectivity is achieved by adjusting pulse duration based on target size.
CONCLUSION
The scatter-limited phototherapy model of the infected periodontium is applied to develop a proper dosimetry for selective photoantisepsis. Dosimetry planning is essential to the development of a new treatment modality. Lasers Surg. Med. 48:763-773, 2016. © 2016 Wiley Periodicals, Inc.
Topics: Antisepsis; Computer Simulation; Humans; Lasers, Semiconductor; Lasers, Solid-State; Models, Anatomic; Periodontal Debridement; Periodontitis; Periodontium; Phototherapy; Porphyromonas gingivalis; Prevotella intermedia
PubMed: 27726169
DOI: 10.1002/lsm.22568 -
Scientific Reports Apr 2022Prevotella intermedia is an important species associated with periodontitis. Despite the remarkable clinical significance, little is known about the molecular basis for...
Prevotella intermedia is an important species associated with periodontitis. Despite the remarkable clinical significance, little is known about the molecular basis for its virulence. The aim of this study was to characterize the secretome of P. intermedia in biofilm and planktonic life mode. The biofilm secretome showed 109 proteins while the planktonic secretome showed 136 proteins. The biofilm and the planktonic secretomes contained 17 and 33 signal-peptide bearing proteins, 13 and 18 lipoproteins, respectively. Superoxide reductase, sensor histidine kinase, C40 family peptidase, elongation factor Tu, threonine synthase etc. were unique to biofilm. Of the ~ 30 proteins with predicted virulence potential from biofilm and planktonic secretomes, only 6 were common between the two groups, implying large differences between biofilm and planktonic modes of P. intermedia. From Gene Ontology biofilm secretome displayed a markedly higher percent proteins compared to planktonic secretome in terms of cellular amino acid metabolic process, nitrogen compound metabolic process etc. Inflammatory cytokine profile analysis revealed that only the biofilm secretome, not the planktonic one, induced important cytokines such as MIP-1α/MIP-1β, IL-1β, and IL-8. In conclusion, the revealed differences in the protein profiles of P. intermedia biofilm and planktonic secretomes may trigger further questions about molecular mechanisms how this species exerts its virulence potential in the oral cavity.
Topics: Biofilms; Plankton; Prevotella intermedia; Proteomics; Secretome
PubMed: 35379855
DOI: 10.1038/s41598-022-09085-0