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Pharmacology Research & Perspectives Feb 2020COR388, a small-molecule lysine-gingipain inhibitor, is currently being investigated in a Phase 2/3 clinical trial for Alzheimer's disease (AD) with exploratory...
COR388, a small-molecule lysine-gingipain inhibitor, is currently being investigated in a Phase 2/3 clinical trial for Alzheimer's disease (AD) with exploratory endpoints in periodontal disease. Gingipains are produced by two species of bacteria, Porphyromonas gingivalis and Porphyromonas gulae, typically associated with periodontal disease and systemic infections in humans and dogs, respectively. P. gulae infection in dogs is associated with periodontal disease, which provides a physiologically relevant model to investigate the pharmacology of COR388. In the current study, aged dogs with a natural oral infection of P. gulae and periodontal disease were treated with COR388 by oral administration for up to 90 days to assess lysine-gingipain target engagement and reduction of bacterial load and downstream pathology. In a 28-day dose-response study, COR388 inhibited the lysine-gingipain target and reduced P. gulae load in saliva, buccal cells, and gingival crevicular fluid. The lowest effective dose was continued for 90 days and was efficacious in continuous reduction of bacterial load and downstream periodontal disease pathology. In a separate histology study, dog brain tissue showed evidence of P. gulae DNA and neuronal lysine-gingipain, demonstrating that P. gulae infection is systemic and spreads beyond its oral reservoir, similar to recent observations of P. gingivalis in humans. Together, the pharmacokinetics and pharmacodynamics of COR388 lysine-gingipain inhibition, along with reduction of bacterial load and periodontal disease in naturally occurring P. gulae infection in the dog, support the use of COR388 in targeting lysine-gingipain and eliminating P. gingivalis infection in humans.
Topics: Administration, Oral; Aging; Animals; Bacterial Load; Bacterial Proteins; Bacteroidaceae Infections; Brain; Dog Diseases; Dogs; Gene Expression Regulation, Bacterial; Gene Expression Regulation, Enzymologic; Gingipain Cysteine Endopeptidases; Gingival Crevicular Fluid; Organic Chemicals; Periodontal Diseases; Porphyromonas; Saliva; Small Molecule Libraries
PubMed: 31999052
DOI: 10.1002/prp2.562 -
Hua Xi Kou Qiang Yi Xue Za Zhi = Huaxi... Feb 2021(), a Gram-negative oral anaerobe, is considered to be a major pathogenic agent involved in the onset and progression of chronic periodontitis. must be able to... (Review)
Review
(), a Gram-negative oral anaerobe, is considered to be a major pathogenic agent involved in the onset and progression of chronic periodontitis. must be able to perceive and respond to the complicated changes in host to survive the environmental challenges, in which the two-component signal transduction systems (TCSs) play critical roles by connecting input signals to cellular physiological output. Canonical TCS consists of a sensor histidine kinase and a cognate response regulator that functions via a phosphorylation cascade. In this review, the roles of TCSs in were demonstrated by illustrating the target genes and modulation modes, which may help elucidate the underlying mechanisms in future studies.
Topics: Phosphorylation; Porphyromonas gingivalis; Signal Transduction
PubMed: 33723942
DOI: 10.7518/hxkq.2021.01.013 -
Frontiers in Cellular and Infection... 2019has been extensively associated with both the onset and progression of periodontitis. We previously isolated and characterized two strains, one from a patient... (Comparative Study)
Comparative Study
has been extensively associated with both the onset and progression of periodontitis. We previously isolated and characterized two strains, one from a patient exhibiting severe chronic periodontitis (CP3) and another from a periodontally healthy individual (H3). We previously showed that CP3 and H3 exhibit differences in virulence since H3 showed a lower resistance to cationic peptides compared with CP3, and a lower ability to induce proliferation in gingival epithelial cells. Here, we aimed to determine whether differences in virulence between these two strains are associated with the presence or absence of specific genes encoding virulence factors. We sequenced the whole genomes of both CP3 and H3 and conducted a comparative analysis regarding virulence genetic determinants. To do so, we performed a homology search of predicted protein sequences in CP3 and H3 genomes against the most characterized virulence genes for available in the literature. In addition, we performed a genomic comparison of CP3 and H3 with all the 62 genomes of found in NCBI's RefSeq database. This approach allowed us to determine the evolutionary relationships of CP3 and H3 with other virulent and avirulent strains; and additionally, to detect variability in presence/absence of virulence genes among genomes. Our results show genetic variability in the hemagglutinin genes. While CP3 possesses one copy of and two of , H3 has no and only one copy of . Experimentally, this finding is related to lower hemmaglutination ability of H3 compared to CP3. Moreover, while CP3 encodes a gene for a major fimbrium subunit FimA type 4 (CP3_00160), H3 possess a FimA type 1 (H3_01400). Such genetic differences are in agreement with both lower biofilm formation ability and less intracellular invasion to oral epithelial cells exhibited by H3, compared with the virulent strain CP3. Therefore, here we provide new results on the genome sequences, comparative genomics analyses, and phenotypic analyses of two strains. The genomics comparison of these two strains with the other 62 genomes included in the analysis provided relevant results regarding genetic determinants and their association with virulence.
Topics: Bacterial Proteins; Biofilms; Case-Control Studies; Cell Line; Chronic Periodontitis; Epithelial Cells; Fimbriae Proteins; Gene Expression Regulation, Bacterial; Gene Ontology; Genetic Variation; Genome, Bacterial; Genomics; Gingiva; Humans; Lectins; Molecular Sequence Annotation; Phenotype; Phylogeny; Porphyromonas gingivalis; Protein Isoforms; Sequence Analysis, DNA; Virulence; Virulence Factors
PubMed: 31355151
DOI: 10.3389/fcimb.2019.00246 -
Journal of Microbiology and... May 2021() is a major bacterial pathogen that causes periodontitis, a chronic inflammatory disease of tissues around the teeth. Periodontitis is known to be related to other...
() is a major bacterial pathogen that causes periodontitis, a chronic inflammatory disease of tissues around the teeth. Periodontitis is known to be related to other diseases, such as oral cancer, Alzheimer's disease, and rheumatism. Thus, a precise and sensitive test to detect is necessary for the early diagnosis of periodontitis. The objective of this study was to optimize a rapid visual detection system for . First, we performed a visual membrane immunoassay using 3,3',5,5'-tetramethylbenzidine (TMB; blue) and coating and detection antibodies that could bind to the host laboratory strain, ATCC 33277. Antibodies against the surface adhesion molecules RgpB (arginine proteinase) and Kgp (lysine proteinase) were determined to be the most specific coating and detection antibodies, respectively. Using these two selected antibodies, the streptavidin-horseradish peroxidase (HRP) reaction was performed using a nitrocellulose membrane and visualized with a detection range of 10-10 bacterial cells/ml following incubation for 15 min. These selected conditions were applied to test other oral bacteria, and the results showed that could be detected without crossreactivity to other bacteria, including and . Furthermore, three clinical strains of , KCOM 2880, KCOM 2803, and KCOM 3190, were also recognized using this optimized enzyme immunoassay (EIA) system. To conclude, we established optimized conditions for detection with specificity, accuracy, and sensitivity. These results could be utilized to manufacture economical and rapid detection kits for .
Topics: Bacteriological Techniques; Colorimetry; Gingipain Cysteine Endopeptidases; Humans; Immunoenzyme Techniques; Limit of Detection; Periodontitis; Porphyromonas gingivalis
PubMed: 33820889
DOI: 10.4014/jmb.2103.03029 -
Journal of Bacteriology Jan 2021Many bacteria switch between a sessile and a motile mode in response to environmental and host-related signals. , an oral anaerobe implicated in the etiology of chronic...
Many bacteria switch between a sessile and a motile mode in response to environmental and host-related signals. , an oral anaerobe implicated in the etiology of chronic periodontal disease, has long been described as a nonmotile bacterium. And yet, recent studies have shown that under certain conditions, is capable of surface translocation. Considering these findings, this work aimed to increase our understanding of how transitions between sessile growth and surface migration. Here, we show that the peptidylarginine deiminase secreted by (PPAD), an enzyme previously shown to be upregulated during surface translocation and to constrain biofilm formation, promotes surface translocation. In the absence of PPAD, the production of outer membrane vesicles (OMVs) was drastically reduced. In turn, there was a reduction in gingipain-mediated proteolysis and a reduced zone of hydration around the site of inoculation. Transcriptome sequencing (RNA-Seq) and metabolomics analyses also showed that these changes corresponded to a shift in arginine metabolism. Overall, this report provides new evidence for the functional relevance of PPAD and proteases, as well as the importance of PPAD activity in OMV biogenesis and release. Our findings support the model that citrullination is a critical mechanism during lifestyle transition between surface-attached growth and surface translocation by modulating OMV-mediated proteolysis and arginine metabolism. Gram-negative bacteria produce nanosized OMVs that are actively released into their surroundings. The oral anaerobe is prolific in OMV production, and many of the proteins packaged in these vesicles are proteolytic or protein-modifying enzymes. This includes key virulence determinants, such as the gingipains and PPAD (a unique peptidylarginine deiminase). Here, we show that PPAD activity (citrullination) is involved in OMV biogenesis. The study revealed an unusual mechanism that allows this bacterium to transform its surroundings. Since OMVs are detected in circulation and in systemic tissues, our study results also support the notion that PPAD activity may be a key factor in the correlation between periodontitis and systemic diseases, further supporting the idea of PPAD as an important therapeutic target.
Topics: Arginine; Bacterial Outer Membrane; Bacterial Proteins; Gene Expression Regulation, Bacterial; Gene Expression Regulation, Enzymologic; Porphyromonas gingivalis; Protein-Arginine Deiminases
PubMed: 33257525
DOI: 10.1128/JB.00343-20 -
Frontiers in Cellular and Infection... 2021Periodontal pathogen and gut microbiota are closely associated with the pathogenesis of Alzheimer's disease (AD). (Pg), the keystone periodontal pathogen, can induce...
BACKGROUND
Periodontal pathogen and gut microbiota are closely associated with the pathogenesis of Alzheimer's disease (AD). (Pg), the keystone periodontal pathogen, can induce cognitive impairment. The gut has a connection and communication with the brain, which is an important aspect of the gut-brain axis (GBA). In the present study, we investigate whether Pg induces cognitive impairment through disturbing the GBA.
METHODS
In this study, Pg was orally administered to mice, three times a week for 1 month. The effects of Pg administration on the gut and brain were evaluated through behaviors, gut microbiota, immune cells, glymphatic pathway clearance, and neuroinflammation.
RESULTS
Pg induced cognitive impairment and dysbiosis of gut microbiota. The α-diversity parameters did not show significant change after Pg administration. The β-diversity demonstrated that the gut microbiota compositions were different between the Pg-administered and control groups. At the species level, the Pg group displayed a lower abundance of and than the control group, but a higher abundance of . The proportions of lymphocytes in the periphery and myeloid cells infiltrating the brain were increased in Pg-treated animals. In addition, the solute clearance efficiency of the glymphatic system decreased. Neurons in the hippocampus and cortex regions were reduced in mice treated with Pg. Microglia, astrocytes, and apoptotic cells were increased. Furthermore, amyloid plaque appeared in the hippocampus and cortex regions in Pg-treated mice.
CONCLUSIONS
These findings indicate that Pg may play an important role in gut dysbiosis, neuroinflammation, and glymphatic system impairment, which may in turn lead to cognitive impairment.
Topics: Animals; Brain-Gut Axis; Cognitive Dysfunction; Dysbiosis; Mice; Neuroinflammatory Diseases; Porphyromonas gingivalis
PubMed: 34926316
DOI: 10.3389/fcimb.2021.755925 -
Microbiology (Reading, England) Nov 2019Key to onset and progression of periodontitis is a complex relationship between oral bacteria and the host. The organisms most associated with severe periodontitis are...
Key to onset and progression of periodontitis is a complex relationship between oral bacteria and the host. The organisms most associated with severe periodontitis are the periodontal pathogens of the red complex: , and . These organisms express sialidases, which cleave sialic acid from host glycoproteins, and contribute to disease through various mechanisms. Here, we expressed and purified recombinant sialidase SiaPG (PG_0352) and characterized its activity on a number of substrates, including host sialoglycoproteins and highlighting the inability to cleave diacetylated sialic acids - a phenomenon overcome by the NanS sialate-esterase from . Indeed SiaPG required NanS to maximize sialic acid harvesting from heavily O-acetylated substrates such as bovine salivary mucin, hinting at the possibility of interspecies cooperation in sialic acid release from host sources by these members of the oral microbiota. Activity of SiaPG and was inhibited using the commercially available chemotherapeutic zanamivir, indicating its potential as a virulence inhibitor, which also inhibited sialic acid release from mucin, and was capable of inhibiting biofilm formation of on oral glycoprotein sources. Zanamivir also inhibited attachment and invasion of oral epithelial cells by and other periodontal pathogens, both in monospecies but also in multispecies infection experiments, indicating potential to suppress host-pathogen interactions of a mixed microbial community. This study broadens our understanding of the multifarious roles of bacterial sialidases in virulence, and indicates that their inhibition with chemotherapeutics could be a promising strategy for periodontitis therapy.
Topics: Bacterial Proteins; Biofilms; Cell Line; Host-Pathogen Interactions; Humans; Microbial Interactions; Mucins; Mutation; Neuraminidase; Polysaccharides; Porphyromonas gingivalis; Recombinant Proteins; Sialoglycoproteins; Tannerella forsythia; Virulence Factors; Zanamivir
PubMed: 31517596
DOI: 10.1099/mic.0.000851 -
BMC Oral Health Dec 2021Dysbiosis in subgingival microbial communities, resulting from increased inflammatory transudate from the gingival tissues, is an important factor in initiation and...
BACKGROUND
Dysbiosis in subgingival microbial communities, resulting from increased inflammatory transudate from the gingival tissues, is an important factor in initiation and development of periodontitis. Dysbiotic communities are characterized by increased numbers of bacteria that exploit the serum-like transudate for nutrients, giving rise to a proteolytic community phenotype. Here we investigate the contribution of interactions between members of a sub-gingival community to survival and development of virulence in a serum environment-modelling that in the subgingival pocket.
METHODS
Growth and proteolytic activity of three Porphyromonas gingivalis strains in nutrient broth or a serum environment were assessed using A and a fluorescent protease substrate, respectively. Adherence of P. gingivalis strains to serum-coated surfaces was studied with confocal microscopy and 2D-gel electrophoresis of bacterial supernatants used to investigate extracellular proteins. A model multi-species sub-gingival community containing Fusobacterium nucleatum, Streptococcus constellatus, Parvimonas micra with wild type or isogenic mutants of P. gingivalis was then created and growth and proteolytic activity in serum assessed as above. Community composition over time was monitored using culture techniques and qPCR.
RESULTS
The P. gingivalis strains showed different growth rates in nutrient broth related to the level of proteolytic activity (largely gingipains) in the cultures. Despite being able to adhere to serum-coated surfaces, none of the strains was able to grow alone in a serum environment. Together in the subgingival consortium however, all the included species were able to grow in the serum environment and the community adopted a proteolytic phenotype. Inclusion of P. gingivalis strains lacking gingipains in the consortium revealed that community growth was facilitated by Rgp gingipain from P. gingivalis.
CONCLUSIONS
In the multi-species consortium, growth was facilitated by the wild-type and Rgp-expressing strains of P. gingivalis, suggesting that Rgp is involved in delivery of nutrients to the whole community through degradation of complex protein substrates in serum. Whereas they are constitutively expressed by P. gingivalis in nutrient broth, gingipain expression in the model periodontal pocket environment (serum) appeared to be orchestrated through signaling to P. gingivalis from other members of the community, a phenomenon which then promoted growth of the whole community.
Topics: Adhesins, Bacterial; Cysteine Endopeptidases; Fusobacterium nucleatum; Gingipain Cysteine Endopeptidases; Porphyromonas gingivalis
PubMed: 34911531
DOI: 10.1186/s12903-021-01971-9 -
International Journal of Nanomedicine 2022Modulating the inflammatory response of human gingival fibroblasts (hGFs) is important for the control of periodontal inflammation because it is a key event in the...
INTRODUCTION
Modulating the inflammatory response of human gingival fibroblasts (hGFs) is important for the control of periodontal inflammation because it is a key event in the pathogenesis of periodontitis. Here, we aimed to determine whether polyglucose sorbitol carboxymethyl ether (PSC)-coated superparamagnetic iron oxide nanoparticles (SPIONs) protect hGFs against invasion and inflammatory stimulation by ().
METHODS
First, we determined the cytotoxicity and antimicrobial activity of PSC-SPIONs. Then, their effects on invasion of hGFs by were evaluated by counting invading , fluorescence staining, and transmission electron microscopy. The effect of PSC-SPIONs on inflammation in hGFs induced by lipopolysaccharide was evaluated by measurement of reactive oxygen species (ROS), and enzyme-linked immunosorbent assays, quantitative reverse transcription-polymerase chain reaction, and Western blotting of key indicator molecules. The effects of dimercaptosuccinic acid (DMSA)-coated SPIONs and the free form of PSC alone were also tested and compared with those of PSC-SPIONs.
RESULTS
PSC-SPIONs (25 μg/mL) are cytocompatible with hGFs and exhibit no antimicrobial effects on . However, they inhibit invasion of hGFs by at 15 μg/mL. They also decrease ROS production and inflammatory cytokine secretion by hGFs at 5, 15, and 25 μg/mL, by downregulating activation of the nuclear factor-kappa B signaling pathway. Furthermore, PSC alone does not inhibit inflammation, while DMSA-SPIONs do. This indicates that the nanosize effects of PSC-SPIONs, rather than their coating material, play the dominant role in their anti-inflammatory activity.
CONCLUSION
PSC-SPIONs protect hGFs against invasion and inflammatory stimulation. Thus, they have potential for clinical application in control of periodontal inflammation.
Topics: Cells, Cultured; Fibroblasts; Gingiva; Humans; Lipopolysaccharides; Porphyromonas gingivalis
PubMed: 35027826
DOI: 10.2147/IJN.S333496 -
Archives of Razi Institute Aug 2022L. and red pomegranate extracts have been reported to inhibit gram-positive facultative anaerobe growth and inhibit the formation of biofilm on tooth surfaces. The...
L. and red pomegranate extracts have been reported to inhibit gram-positive facultative anaerobe growth and inhibit the formation of biofilm on tooth surfaces. The current study aimed to assess the antibacterial effect of L. and red pomegranate extracts and their combinations against . The antimicrobial sensitivity, minimum inhibition concentrations (MIC), and minimum bactericidal concentrations after treatment with the aqueous extracts of L. and red pomegranate as well as their combination against clinically isolated were determined using agar well diffusion and two-fold serial dilution. The anti-biofilm activity of the extracts and their combination was evaluated using the tube adhesion method. The phytochemical analysis was carried out using gas chromatography-mass spectrometry. It was found that was sensitive to aqueous extract of L. seeds and red pomegranate albedo, however, not to L. leaves and red pomegranate seeds. The MIC value of L. seeds, red pomegranate albedo, and their combination were obtained at 12.5 mg/ml, 6.25 mg/ml, and 3.12 mg/ml against , respectively. The extract combination had the highest anti-biofilm effect than L. seeds and red pomegranate albedo aqueous extracts at the minimum concentrations of 6.25 mg/ml, 25 mg/ml, and 12.5 mg/ml, respectively. The combination of red pomegranate albedo and L. seeds showed superior antibacterial and anti-biofilm effects against , followed by red pomegranate albedo and L. seeds. This may highlight a promising alternative to the traditional chemicals that can be used as an adjunct in the treatment of periodontal diseases.
Topics: Animals; Porphyromonas gingivalis; Moringa oleifera; Pomegranate; Seeds; Anti-Bacterial Agents
PubMed: 36883151
DOI: 10.22092/ARI.2022.357513.2051