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Arthritis Research & Therapy Oct 2020Porphyromonas gingivalis (Pg) infection causes periodontal disease and exacerbates rheumatoid arthritis (RA). It is reported that inoculation of periodontopathogenic...
BACKGROUND
Porphyromonas gingivalis (Pg) infection causes periodontal disease and exacerbates rheumatoid arthritis (RA). It is reported that inoculation of periodontopathogenic bacteria (i.e., Pg) can alter gut microbiota composition in the animal models. Gut microbiota dysbiosis in human has shown strong associations with systemic diseases, including RA, diabetes mellitus, and inflammatory bowel disease. Therefore, this study investigated dysbiosis-mediated arthritis by Pg oral inoculation in an experimental arthritis model mouse.
METHODS
Pg inoculation in the oral cavity twice a week for 6 weeks was performed to induce periodontitis in SKG mice. Concomitantly, a single intraperitoneal (i.p.) injection of laminarin (LA) was administered to induce experimental arthritis (Pg-LA mouse). Citrullinated protein (CP) and IL-6 levels in serum as well as periodontal, intestinal, and joint tissues were measured by ELISA. Gut microbiota composition was determined by pyrosequencing the 16 s ribosomal RNA genes after DNA purification of mouse feces. Fecal microbiota transplantation (FMT) was performed by transferring Pg-LA-derived feces to normal SKG mice. The effects of Pg peptidylarginine deiminase (PgPAD) on the level of citrullinated proteins and arthritis progression were determined using a PgPAD knockout mutant.
RESULTS
Periodontal alveolar bone loss and IL-6 in gingival tissue were induced by Pg oral infection, as well as severe joint destruction, increased arthritis scores (AS), and both IL-6 and CP productions in serum, joint, and intestinal tissues. Distribution of Deferribacteres and S24-7 was decreased, while CP was significantly increased in gingiva, joint, and intestinal tissues of Pg-inoculated experimental arthritis mice compared to experimental arthritis mice without Pg inoculation. Further, FMT from Pg-inoculated experimental arthritis mice reproduced donor gut microbiota and resulted in severe joint destruction with increased IL-6 and CP production in joint and intestinal tissues. The average AS of FMT from Pg-inoculated experimental arthritis was much higher than that of donor mouse. However, inoculation of the PgPAD knockout mutant inhibited the elevation of arthritis scores and ACPA level in serum and reduced CP amount in gingival, joint, and intestinal tissues compared to Pg wild-type inoculation.
CONCLUSION
Pg oral infection affected gut microbiota dysbiosis and joint destruction via increased CP generation.
Topics: Animals; Arthritis, Experimental; Dysbiosis; Mice; Periodontitis; Porphyromonas gingivalis; Protein-Arginine Deiminases
PubMed: 33076980
DOI: 10.1186/s13075-020-02348-z -
Antimicrobial Agents and Chemotherapy May 2020Periodontitis as a biofilm-associated inflammatory disease is highly prevalent worldwide. It severely affects oral health and yet closely links to systemic diseases like...
Periodontitis as a biofilm-associated inflammatory disease is highly prevalent worldwide. It severely affects oral health and yet closely links to systemic diseases like diabetes and cardiovascular disease. as a "keystone" periodontopathogen drives the shift of microbe-host symbiosis to dysbiosis and critically contributes to the pathogenesis of periodontitis. Persisters represent a tiny subset of biofilm-associated microbes highly tolerant to lethal treatment of antimicrobials, and, notably, metronidazole-tolerant persisters have recently been identified by our group. This study further explored the interactive profiles of metronidazole-treated persisters (M-PgPs) with human gingival epithelial cells (HGECs). cells (ATCC 33277) at stationary phase were treated with a lethal dosage of metronidazole (100 μg/ml, 6 h) for generating M-PgPs. The interaction of M-PgPs with HGECs was assessed by microscopy, flow cytometry, cytokine profiling, and quantitative PCR (qPCR). We demonstrated that the overall morphology and ultracellular structure of M-PgPs remained unchanged. Importantly, M-PgPs maintained the capabilities to adhere to and invade HGECs. Moreover, M-PgPs significantly suppressed proinflammatory cytokine expression in HGECs at a level comparable to that seen with the untreated cells, through the thermosensitive components. The present report reveals that persisters induced by lethal treatment of antibiotics were able to maintain their capabilities to adhere to and invade human gingival epithelial cells and to perturb the innate host responses. Novel strategies and approaches need to be developed for tackling and favorably modulating the dysregulated immunoinflammatory responses for oral/periodontal health and general well-being.
Topics: Cells, Cultured; Epithelial Cells; Gingiva; Humans; Metronidazole; Periodontitis; Porphyromonas gingivalis
PubMed: 32205352
DOI: 10.1128/AAC.02529-19 -
PloS One 2019Porphyromonas gulae, an animal periodontal pathogen, possess fimbriae classified into three genotypes (A-C) based on the diversity of fimA genes encoding FimA....
Porphyromonas gulae, an animal periodontal pathogen, possess fimbriae classified into three genotypes (A-C) based on the diversity of fimA genes encoding FimA. Accumulating evidence suggests that P. gulae strains with type C fimbriae are more virulent as compared to those with other types. The ability of these organisms to adhere to and invade gingival epithelial cells has yet to be examined. P. gulae showed the greatest levels of adhesion and invasion at a multiplicity of infection of 100 for 90 min. P. gulae type C and some type B strains invaded gingival epithelial cells at significantly greater levels than the other strains, at the same level of efficiency as P. gingivalis with type II fimbriae. Adhesion and invasion of gingival epithelial cells by P. gulae were inhibited by cytochalasin D and sodium azide, indicating the requirements of actin polymerization and energy metabolism for those activities. Invasion within gingival epithelial cells was blocked by staurosporine, whereas those inhibitors showed little effects on adhesion, while nocodazole and cycloheximide had negligible effects on either adhesion or invasion. P. gulae proteases were found to be essential for adhesion and invasion of gingival epithelial cells, while its DNA and RNA, and protein synthesis were unnecessary for those activities. Additionally, α5β1 integrin antibodies significantly inhibited adhesion and invasion by P. gulae. This is the first report to characterize P. gulae adhesion and invasion of human gingival epithelial cells.
Topics: Bacterial Adhesion; Bacteroidaceae Infections; Epithelial Cells; Fimbriae, Bacterial; Gingiva; Humans; Integrin alpha5beta1; Porphyromonas
PubMed: 30870452
DOI: 10.1371/journal.pone.0213309 -
International Journal of Environmental... Jul 2022Alzheimer's Disease (AD) is a complex neurodegenerative disease and remains the most common form of dementia. The pathological features include amyloid (Aβ)... (Review)
Review
Alzheimer's Disease (AD) is a complex neurodegenerative disease and remains the most common form of dementia. The pathological features include amyloid (Aβ) accumulation, neurofibrillary tangles (NFTs), neural and synaptic loss, microglial cell activation, and an increased blood-brain barrier permeability. One longstanding hypothesis suggests that a microbial etiology is key to AD initiation. Among the various periodontal microorganisms, has been considered the keystone agent to potentially correlate with AD, due to its influence on systemic inflammation. together with and belong to the red complex consortium of bacteria advocated to sustain periodontitis within a local dysbiosis and a host response alteration. Since the implication of in the pathogenesis of AD, evidence has emerged of clusters in some AD brain tissue sections. This narrative review explored the potential mode of spirochetes entry into the AD brain for tracing pathology. Spirochetes are slow-growing bacteria, which can hide within ganglia for many years. It is this feature in combination with the ability of these bacteria to evade the hosts' immune responses that may account for a long lag phase between infection and plausible AD disease symptoms. As the locus coeruleus has direct connection between the trigeminal nuclei to periodontal free nerve endings and proprioceptors with the central nervous system, it is plausible that they could initiate AD pathology from this anatomical region.
Topics: Alzheimer Disease; Brain; Humans; Neurodegenerative Diseases; Porphyromonas gingivalis; Treponema denticola
PubMed: 35954742
DOI: 10.3390/ijerph19159386 -
Journal of Molecular Biology Dec 2022Porphyromonas gingivalis is a gram-negative oral anaerobic pathogen and is one of the key causative agents of periodontitis. P. gingivalis utilises a range of virulence...
Porphyromonas gingivalis is a gram-negative oral anaerobic pathogen and is one of the key causative agents of periodontitis. P. gingivalis utilises a range of virulence factors, including the cysteine protease RgpB, to drive pathogenesis and these are exported and attached to the cell surface via the type IX secretion system (T9SS). All cargo proteins possess a conserved C-terminal signal domain (CTD) which is recognised by the T9SS, and the outer membrane β-barrel protein PorV (PG0027/LptO) can interact with cargo proteins as they are exported to the bacterial surface. Using a combination of solution nuclear magnetic resonance (NMR) spectroscopy, biochemical analyses, machine-learning-based modelling and molecular dynamics (MD) simulations, we present a structural model of a PorV:RgpB-CTD complex from P. gingivalis. This is the first structural insight into CTD recognition by the T9SS and shows how the conserved motifs in the CTD are the primary sites that mediate binding. In PorV, interactions with extracellular surface loops are important for binding the CTD, and together these appear to cradle and lock RgpB-CTD in place. This work provides insight into cargo recognition by PorV but may also have important implications for understanding other aspects of type-IX dependent secretion.
Topics: Bacterial Proteins; Membrane Proteins; Porphyromonas gingivalis; Virulence Factors; Bacterial Secretion Systems; Molecular Dynamics Simulation; Protein Domains
PubMed: 36404438
DOI: 10.1016/j.jmb.2022.167871 -
PloS One 2017Porphyromonas gingivalis, a periodontopathic gram-negative anaerobic bacterium, generally expresses two types of fimbriae, FimA and Mfa1. However, a novel potential...
Porphyromonas gingivalis, a periodontopathic gram-negative anaerobic bacterium, generally expresses two types of fimbriae, FimA and Mfa1. However, a novel potential fimbrilin, PGN_1808, in P. gingivalis strain ATCC 33277 was recently identified by an in silico structural homology search. In this study, we experimentally examined whether the protein formed a fimbrial structure. Anion-exchange chromatography showed that the elution peak of the protein was not identical to those of the major fimbrilins of FimA and Mfa1, indicating that PGN_1808 is not a component of these fimbriae. Electrophoretic analyses showed that PGN_1808 formed a polymer, although it was detergent and heat labile compared to FimA and Mfa1. Transmission electron microscopy showed filamentous structures (2‒3 nm × 200‒400 nm) on the cell surfaces of a PGN_1808-overexpressing P. gingivalis mutant (deficient in both FimA and Mfa1 fimbriae) and in the PGN_1808 fraction. PGN_1808 was detected in 81 of 84 wild-type strains of P. gingivalis by western blotting, suggesting that the protein is generally present in P. gingivalis.
Topics: Amino Acid Sequence; Bacterial Proteins; Chromatography, Gel; Chromatography, Ion Exchange; Electrophoresis, Polyacrylamide Gel; Fimbriae Proteins; Mass Spectrometry; Microscopy, Electron, Transmission; Models, Molecular; Porphyromonas gingivalis; Protein Conformation
PubMed: 28296909
DOI: 10.1371/journal.pone.0173541 -
Journal of Microbiology, Immunology,... Jun 2014The coaggregation of bacteria has been defined as one of the most important processes in the oral infection such as periodontitis. Prevotella oris and Porphyromonas...
BACKGROUND/PURPOSE
The coaggregation of bacteria has been defined as one of the most important processes in the oral infection such as periodontitis. Prevotella oris and Porphyromonas gingivalis, which are two of the periodontopathogens, are frequently detected in severe forms of periodontal diseases. However, the interaction between P. oris and P. gingivalis is still unknown. In this study, the coaggregation of P. oris with nine oral bacterial species including P. gingivalis was examined.
METHODS
All bacteria used in this study were cultured anaerobically and suspended in coaggregation buffer. Each cell suspension was mixed in a test tube and subjected to shaking at room temperature for 1 hour. Subsequently, the coaggregation values were scored. Furthermore, the effects of various chemical reagents, and heat, proteinase K, and serum treatment were examined.
RESULTS
In this study, P. oris coaggregated only with P. gingivalis. A heat-stable, nonproteinous component of P. oris and a heat-labile, proteinous component of P. gingivalis play important roles in this coaggregation. In addition, this coaggregation was inhibited by l-arginine, l-lysine, and Nα-p-tosyl-l-lysine. Therefore, it was considered that a cell surface protein on P. gingivalis, such as gingipain, may be involved in the coaggregation. Furthermore, the coaggregation was not inhibited by serum treatment.
CONCLUSION
This is the first report to describe the coaggregation of P. oris and P. gingivalis. Our study proposes the possibility that P. oris may promote the colonization of P. gingivalis in an early stage of biofilm formation. Furthermore, this coaggregation may contribute to the initiation and progression of periodontitis.
Topics: Animals; Biofilms; Coculture Techniques; Endopeptidase K; Horses; Hot Temperature; Humans; Microbial Interactions; Periodontitis; Porphyromonas gingivalis; Prevotella; Serum
PubMed: 23245806
DOI: 10.1016/j.jmii.2012.09.005 -
Future Microbiology May 2013Porphyromonas gingivalis is a Gram-negative anaerobic bacterium that colonizes the human oral cavity. It is implicated in the development of periodontitis, a chronic... (Review)
Review
Porphyromonas gingivalis is a Gram-negative anaerobic bacterium that colonizes the human oral cavity. It is implicated in the development of periodontitis, a chronic periodontal disease affecting half of the adult population in the USA. To survive in the oral cavity, these bacteria must colonize dental plaque biofilms in competition with other bacterial species. Long-term survival requires P. gingivalis to evade host immune responses, while simultaneously adapting to the changing physiology of the host and to alterations in the plaque biofilm. In reflection of this highly variable niche, P. gingivalis is a genetically diverse species and in this review the authors summarize genetic diversity as it relates to pathogenicity in P. gingivalis. Recent studies revealing a variety of mechanisms by which adaptive changes in genetic content can occur are also reviewed. Understanding the genetic plasticity of P. gingivalis will provide a better framework for understanding the host-microbe interactions associated with periodontal disease.
Topics: Adaptation, Physiological; Genetic Variation; Host-Pathogen Interactions; Humans; Mouth; Periodontitis; Porphyromonas gingivalis; Virulence
PubMed: 23642116
DOI: 10.2217/fmb.13.30 -
Journal of Dental Research Nov 2008Quantitative proteomic analysis of microbial systems generates large datasets that can be difficult and time-consuming to interpret. Fortunately, many of the data... (Review)
Review
Quantitative proteomic analysis of microbial systems generates large datasets that can be difficult and time-consuming to interpret. Fortunately, many of the data display and gene-clustering tools developed to analyze large transcriptome microarray datasets are also applicable to proteomes. Plots of abundance ratio vs. total signal or spectral counts can highlight regions of random error and putative change. Displaying data in the physical order of the genes in the genome sequence can highlight potential operons. At a basic level of transcriptional organization, identifying operons can give insights into regulatory pathways as well as provide corroborating evidence for proteomic results. Classification and clustering algorithms can group proteins together by their abundance changes under different conditions, helping to identify interesting expression patterns, but often work poorly with noisy data such as typically generated in a large-scale proteomic analysis. Biological interpretation can be aided more directly by overlaying differential protein abundance data onto metabolic pathways, indicating pathways with altered activities. More broadly, ontology tools detect altered levels of protein abundance for different metabolic pathways, molecular functions, and cellular localizations. In practice, pathway analysis and ontology are limited by the level of database curation associated with the organism of interest.
Topics: Bacterial Proteins; Classification; Cluster Analysis; Databases, Protein; Gene Expression Profiling; Metabolic Networks and Pathways; Methanococcus; Porphyromonas gingivalis; Protein Array Analysis; Proteomics
PubMed: 18946006
DOI: 10.1177/154405910808701113 -
Frontiers in Cellular and Infection... 2021Polymicrobial interactions with oral mucosal surfaces determine the health status of the host. While a homeostatic balance provides protection from oral disease, a...
Polymicrobial interactions with oral mucosal surfaces determine the health status of the host. While a homeostatic balance provides protection from oral disease, a dysbiotic polymicrobial community promotes tissue destruction and chronic oral diseases. How polymicrobial communities transition from a homeostatic to a dysbiotic state is an understudied process. Thus, we were interested to investigate this ecological transition by focusing on biofilm communities containing high abundance commensal species and low abundance pathobionts to characterize the host-microbiome interactions occurring during oral health. To this end, a multispecies biofilm model was examined using the commensal species and and the pathobiont . We compared how both single and multispecies biofilms interact with different oral mucosal and gingival cell types, including the well-studied oral keratinocyte cell lines OKF4/TERT-1and hTERT TIGKs as well as human primary periodontal ligament cells. While single species biofilms of , , and are all characterized by unique cytokine responses for each species, multispecies biofilms elicited a response resembling single species biofilms. One notable exception is the influence of upon TNF-α and Gro-α production in hTERT TIGKs cells, which was not affected by the presence of other species. This study is also the first to examine the host response to . Interestingly, yielded no notable inflammatory responses from any of the tested host cells, suggesting it functions as a true commensal species. Conversely, was able to induce expression and secretion of the proinflammatory cytokines IL-6 and IL-8, demonstrating a much greater inflammatory potential, despite being health associated. Our study also demonstrates the variability of host cell responses between different cell lines, highlighting the importance of developing relevant models to study oral microbiome-host interactions.
Topics: Biofilms; Corynebacterium; Humans; Porphyromonas gingivalis; Streptococcus sanguis
PubMed: 34277471
DOI: 10.3389/fcimb.2021.686479