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Medicina (Kaunas, Lithuania) Nov 2023: More than a billion people worldwide suffer from chronic periodontitis. The primary etiological factor of periodontal diseases is dental plaque and the bacteria it... (Review)
Review
: More than a billion people worldwide suffer from chronic periodontitis. The primary etiological factor of periodontal diseases is dental plaque and the bacteria it contains, particularly , , , , and . Zinc, owing to its antibacterial properties, can be employed in periodontology. The objective of this review was to analyze scientific literature that examines the effects of zinc on periopathogens. : A systematic review protocol of scientific literature was designed following PRISMA recommendations. Data search was conducted in PubMed, Web of Science, and ScienceDirect databases. Full-text articles in English that examine the effects of zinc on periopathogens and were published between 2011 and 2021 were included. Fifteen articles were included in the analysis based on inclusion criteria. ZnO exhibited antibacterial activity against and ( < 0.001). The minimum inhibitory concentration against was 10 μg/mL. ZnO demonstrated a significant antibacterial effect, as evidenced by inhibition zones of 15.10 mm for , 13.36 mm for , 12.98 mm for , and 14.01 mm for Zn (II)-based polymers inhibited the and genes of . Titanium dental implants coated with ZnO effectively disrupted the cell walls of and . ZnO inhibited the growth of within 2 h and the growth of and within 3 h. ZnO exhibited nontoxic effects, and concentrations up to 0.8 mg/L increased cell survival rates by up to 90%. The analysis of the literature confirms the antibacterial action of zinc against periodontal pathogenic bacteria. At low concentrations, these substances do not exhibit cytotoxic effects on fibroblasts.
Topics: Humans; Anti-Bacterial Agents; Anti-Infective Agents; Chronic Periodontitis; Organic Chemicals; Porphyromonas gingivalis; Systematic Reviews as Topic; Zinc; Zinc Oxide
PubMed: 38138191
DOI: 10.3390/medicina59122088 -
International Dental Journal Dec 2023The aim of this research was to investigate the role of the cornified epithelium, the outermost layer of the oral mucosa, engineered to prevent water loss and...
OBJECTIVE
The aim of this research was to investigate the role of the cornified epithelium, the outermost layer of the oral mucosa, engineered to prevent water loss and microorganism invasion, in severe forms of periodontitis (stage III or IV, grade C).
METHODS
Porphyromonas gingivalis, a major periodontal disease pathogen, can affect cornified epithelial protein expression through chronic activation of signal transducer and activator of transcription 6 (Stat6). We used a mouse model, Stat6VT, that mimics this to determine the effects of barrier defect on P gingivalis-induced inflammation, bone loss, and cornified epithelial protein expression, and compared histologic and immunohistologic findings with tissues obtained from human controls and patients with stage III and IV, grade C disease. Alveolar bone loss in mice was assessed using micro-computerised tomography, and soft tissue morphology was qualitatively and semi-quantitatively assessed by histologic examination for several proteins, including loricrin, filaggrin, cytokeratin 1, cytokeratin 14, a proliferation marker, a pan-leukocyte marker, as well as morphologic signs of inflammation. Relative cytokine levels were measured in mouse plasma by cytokine array.
RESULTS
In the tissues from patients with periodontal disease, there were greater signs of inflammation (rete pegs, clear cells, inflammatory infiltrates) and a decrease and broadening of expression of loricrin and cytokeratin 1. Cytokeratin 14 expression was also broader and decreased in stage IV. P gingivalis-infected Stat6VT mice showed greater alveolar bone loss in 9 out of 16 examined sites, and similar patterns of disruption to human patients in expression of loricrin and cytokeratins 1 and 14. There were also increased numbers of leukocytes, decreased proliferation, and greater signs of inflammation compared with P gingivalis-infected control mice.
CONCLUSIONS
Our study provides evidence that changes in epithelial organisation can exacerbate the effects of P gingivalis infection, with similarities to the most severe forms of human periodontitis.
Topics: Humans; Mice; Animals; Alveolar Bone Loss; Keratin-14; Keratins; Periodontitis; Inflammation; Cytokines; Porphyromonas gingivalis
PubMed: 37316411
DOI: 10.1016/j.identj.2023.05.004 -
Microbes and Infection 2023Tanshinone IIA (TSA), an active component isolated from Danshen, possess high medicinal values against atherosclerosis by reducing vascular oxidative stress, inhibiting...
Protective effects of tanshinone IIA on Porphyromonas gingivalis-induced atherosclerosis via the downregulation of the NOX2/NOX4-ROS mediation of NF-κB signaling pathway.
Tanshinone IIA (TSA), an active component isolated from Danshen, possess high medicinal values against atherosclerosis by reducing vascular oxidative stress, inhibiting platelet aggregation, and protecting the endothelium from damage. The periodontal pathogen Porphyromonas gingivalis (P. gingivalis) has been proven to accelerate the development of atherosclerosis. We aim to determine the effects of TSA on P. gingivalis-induced atherosclerosis in ApoE-knockout (ApoE-/-) mice. After feeding with a high-lipid diet and infected with P. gingivalis three times per week for four weeks, TSA-treated (60 mg/kg/d) mice greatly inhibited atherosclerotic lesions both morphologically and biochemically and exhibited significantly reduction ROS, 8-OHdG, and ox-LDL levels in serum compared with P. gingivalis-infected mice. Additionally, TSA-treated mice were observed a marked reduction of ROS, 8-OHdG and ox-LDL in the serum, mRNA levels of COX-2, LOX-1, NOX2 and NOX4 in the aorta, as well as the levels of NOX2, NOX4, and NF-κB. These results suggest that TSA attenuates oxidative stress by decreasing NOX2 and NOX4 and downregulating NF-κB signaling pathway, which might be contributed to the amelioration of atherosclerosis.
Topics: Animals; Mice; NF-kappa B; Reactive Oxygen Species; Porphyromonas gingivalis; Down-Regulation; Signal Transduction; Atherosclerosis; Apolipoproteins E
PubMed: 37392987
DOI: 10.1016/j.micinf.2023.105177 -
International Journal of Molecular... Jan 2024() is a key pathogen of periodontitis. Increasing evidence shows that signals to mitochondria in periodontal cells, including gingival epithelial cells, gingival... (Review)
Review
() is a key pathogen of periodontitis. Increasing evidence shows that signals to mitochondria in periodontal cells, including gingival epithelial cells, gingival fibroblast cells, immune cells, etc. Mitochondrial dysfunction affects the cellular state and participates in periodontal inflammatory response through the aberrant release of mitochondrial contents. In the current review, it was summarized that induced mitochondrial dysfunction by altering the mitochondrial metabolic state, unbalancing mitochondrial quality control, prompting mitochondrial reactive oxygen species (ROS) production, and regulating mitochondria-mediated apoptosis. This review outlines the impacts of and its virulence factors on the mitochondrial function of periodontal cells and their role in periodontitis.
Topics: Humans; Porphyromonas gingivalis; Mitochondria; Periodontitis; Apoptosis; Mitochondrial Diseases
PubMed: 38255811
DOI: 10.3390/ijms25020737 -
Frontiers in Cellular and Infection... 2024and belong to the Bacteroidota phylum. Both species inhabit the oral cavity and can be associated with periodontal diseases. To survive, they must uptake heme from the...
INTRODUCTION
and belong to the Bacteroidota phylum. Both species inhabit the oral cavity and can be associated with periodontal diseases. To survive, they must uptake heme from the host as an iron and protoporphyrin IX source. Among the best-characterized heme acquisition systems identified in members of the Bacteroidota phylum is the Hmu system, with a leading role played by the hemophore-like HmuY (HmuY) protein.
METHODS
Theoretical analysis of selected HmuY proteins and spectrophotometric methods were employed to determine the heme-binding mode of the HmuY homolog (HmuY) and its ability to sequester heme. Growth phenotype and gene expression analysis of were employed to reveal the importance of the HmuY and Hmu system for this bacterium.
RESULTS
Unlike in , where HmuY uses two histidines for heme-iron coordination, other known HmuY homologs use two methionines in this process. HmuY is the first characterized representative of the HmuY family that binds heme using a histidine-methionine pair. It allows HmuY to sequester heme directly from serum albumin and HmuY, the HmuY homolog which uses two methionines for heme-iron coordination. In contrast to HmuY, which sequesters heme directly from methemoglobin, HmuY may bind heme only after the proteolytic digestion of hemoglobin.
CONCLUSIONS
We hypothesize that differences in components of the Hmu system and structure-based properties of HmuY proteins may evolved allowing different adaptations of species to the changing host environment. This may add to the superior virulence potential of over other members of the Bacteroidota phylum.
Topics: Heme; Porphyromonas gingivalis; Tannerella forsythia; Bacterial Proteins; Porphyromonas endodontalis; Humans; Gene Expression Regulation, Bacterial; Protein Binding; Iron
PubMed: 38938884
DOI: 10.3389/fcimb.2024.1421018 -
Scientific Reports Nov 2023The objective of this study was to compare and evaluate the changes in periodontal pathogens and periodontal status within 6 months of wearing three orthodontic...
The objective of this study was to compare and evaluate the changes in periodontal pathogens and periodontal status within 6 months of wearing three orthodontic retainers, namely, vacuum-formed retainer (VFR), Hawley retainer (HR), and lingual fixed retainer (LR). In total, 48 patients who underwent orthodontic treatment with ordinary metal brackets were divided into VFR, HR, and LR groups (n = 16 per group). Saliva samples were collected at the time of debonding (T0) and after 1 month (T1), 3 months (T2), and 6 months (T3). Porphyromonas gingivalis (Pg) and Aggregatibacter actinomycetemcomitans (Aa) were quantitatively analyzed using real-time PCR. Gingival index (GI), plaque index (PLI), and probing depth (PD) were measured at the four time points to evaluate changes in periodontal state. SPSS20.0 software was used to analyze the data, and P < 0.05 was considered statistically significant. The trial was registered at the Chinese Clinical Trial Registry (ChiCTR2300073704), the registration was retrospective. Compared to baseline (T0) values, Pg, Aa, GI, PLI, and PD were significantly decreased in all three groups 1 month after wearing the retainer (p < 0.05). Significant differences were observed in Aa at T3 among the three groups, whereby the HR group exhibited significantly better results compared to the VFR and LR groups (p < 0.05). Differences were found among the three groups' Porphyromonas gingivalis at T3, and the HR group was significantly better than the VFR and LR groups (P < 0.05). From T1 to T2, GI, PLI, and PD of the three groups tended to be stable, however differences were observed at T3, with the PLI and PD of the HR group being the lowest among the three groups (p < 0.05). Regardless of the type of retainer used, the periodontal condition of patients was significantly improved after removal of the metal brackets. After 6 months of retainer use, the Hawley retainer was superior to vacuum-formed retainer and lingual fixed retainer with regard to Pg, Aa, and periodontal clinical parameters.
Topics: Humans; Orthodontic Retainers; Retrospective Studies; Porphyromonas gingivalis; Orthodontic Appliances, Fixed; Gingival Diseases
PubMed: 38001102
DOI: 10.1038/s41598-023-46922-2 -
Journal of Molecular Biology May 2024Porphyromonas gingivalis, an anaerobic CFB (Cytophaga, Fusobacterium, and Bacteroides) group bacterium, is the keystone pathogen of periodontitis and has been implicated...
Porphyromonas gingivalis, an anaerobic CFB (Cytophaga, Fusobacterium, and Bacteroides) group bacterium, is the keystone pathogen of periodontitis and has been implicated in various systemic diseases. Increased antibiotic resistance and lack of effective antibiotics necessitate a search for new intervention strategies. Here we report a 3.5 Å resolution cryo-EM structure of P. gingivalis RNA polymerase (RNAP). The structure displays new structural features in its ω subunit and multiple domains in β and β' subunits, which differ from their counterparts in other bacterial RNAPs. Superimpositions with E. coli RNAP holoenzyme and initiation complex further suggest that its ω subunit may contact the σ4 domain, thereby possibly contributing to the assembly and stabilization of initiation complexes. In addition to revealing the unique features of P. gingivalis RNAP, our work offers a framework for future studies of transcription regulation in this important pathogen, as well as for structure-based drug development.
Topics: Bacterial Proteins; Cryoelectron Microscopy; DNA-Directed RNA Polymerases; Escherichia coli; Models, Molecular; Porphyromonas gingivalis; Protein Conformation; Protein Subunits
PubMed: 38583515
DOI: 10.1016/j.jmb.2024.168568 -
Frontiers in Oral Health 2024Accumulating microbiome data and mechanistic studies and have refined our understanding of the oral microbiota as a functionally integrated polymicrobial community....
Accumulating microbiome data and mechanistic studies and have refined our understanding of the oral microbiota as a functionally integrated polymicrobial community. Emergent properties of these communities are driven to a large extent by interspecies communication which can be based on physical association, secreted small molecules or nutritional exchange. is a consensus periodontal pathogen; however, virulence is only expressed in the context of a polymicrobial community. Multivalent fimbriae mediate attachment to other oral species which can initiate a distinct transcriptional program in both constituents of the binding pair. also responds to small molecules and nutritional cues produced by partner organisms. Physiological interdependence forms the basis of complex networks of cooperating organisms which begin to resemble an organismal entity exhibiting a spectrum of pathogenic potential.
PubMed: 38736461
DOI: 10.3389/froh.2024.1404917 -
Journal of Medical Microbiology Mar 2024There is growing evidence that altered microbiota abundance of a range of specific anaerobic bacteria are associated with cancer, including spp., spp., spp., spp.,... (Review)
Review
There is growing evidence that altered microbiota abundance of a range of specific anaerobic bacteria are associated with cancer, including spp., spp., spp., spp., spp., spp spp and spp. linked to multiple cancer types. In this review we explore these pathogenic associations. The mechanisms by which bacteria are known or predicted to interact with human cells are reviewed and we present an overview of the interlinked mechanisms and hypotheses of how multiple intracellular anaerobic bacterial pathogens may act together to cause host cell and tissue microenvironment changes associated with carcinogenesis and cancer cell invasion. These include combined effects on changes in cell signalling, DNA damage, cellular metabolism and immune evasion. Strategies for early detection and eradication of anaerobic cancer-associated bacterial pathogens that may prevent cancer progression are proposed.
Topics: Humans; Bacteria, Anaerobic; Carcinogenesis; Immune Evasion; Porphyromonas; Signal Transduction; Tumor Microenvironment
PubMed: 38535967
DOI: 10.1099/jmm.0.001817 -
Small (Weinheim An Der Bergstrasse,... Dec 2023Bacterial therapy is an emerging hotspot in tumor immunotherapy, which can initiate antitumor immune activation through multiple mechanisms. Porphyromonas gingivalis...
Bacterial therapy is an emerging hotspot in tumor immunotherapy, which can initiate antitumor immune activation through multiple mechanisms. Porphyromonas gingivalis (Pg), a pathogenic bacterium inhabiting the oral cavity, contains a great deal of pathogen associated molecular patterns that can activate various innate immune cells to promote antitumor immunity. Owing to the presence of protoporphyrin IX (PpIX), Pg is also an excellent photosensitizer for photodynamic therapy (PDT) via the in situ generation of reactive oxygen species. This study reports a bacterial nanomedicine (nmPg) fabricated from Pg through lysozyme degradation, ammonium chloride lysis, and nanoextrusion, which has potent PDT and immune activation performances for oral squamous cell carcinoma (OSCC) treatment. To further promote the tumoricidal efficacy, a commonly used chemotherapeutic drug doxorubicin (DOX) is efficiently encapsulated into nmPg through a simple incubation method. nmPg/DOX thus prepared exhibits significant synergistic effects on inhibiting the growth and metastasis of OSCC both in vitro and in vivo via photodynamic-immunotherapy and chemotherapy. In summary, this work develops a promising bacterial nanomedicine for enhanced treatment of OSCC.
Topics: Humans; Carcinoma, Squamous Cell; Squamous Cell Carcinoma of Head and Neck; Mouth Neoplasms; Photochemotherapy; Nanomedicine; Photosensitizing Agents; Doxorubicin; Head and Neck Neoplasms; Immunotherapy; Cell Line, Tumor
PubMed: 37653616
DOI: 10.1002/smll.202304014