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1.
Infect Immun ; 87(12)2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31570556

RESUMO

The Porphyromonas gingivalis strain ATCC 33277 (33277) and 381 genomes are nearly identical. However, strain 33277 displays a significantly diminished capacity to stimulate host cell Toll-like receptor 2 (TLR2)-dependent signaling and interleukin-1ß (IL-1ß) production relative to 381, suggesting that there are strain-specific differences in one or more bacterial immune-modulatory factors. Genomic sequencing identified a single nucleotide polymorphism in the 33277 fimB allele (A→T), creating a premature stop codon in the 33277 fimB open reading frame relative to the 381 fimB allele. Gene exchange experiments established that the 33277 fimB allele reduces the immune-stimulatory capacity of this strain. Transcriptome comparisons revealed that multiple genes related to carboxy-terminal domain (CTD) family proteins, including the gingipains, were upregulated in 33277 relative to 381. A gingipain substrate degradation assay demonstrated that cell surface gingipain activity is higher in 33277, and an isogenic mutant strain deficient for the gingipains exhibited an increased ability to induce TLR2 signaling and IL-1ß production. Furthermore, 33277 and 381 mutant strains lacking CTD cell surface proteins were more immune-stimulatory than the parental wild-type strains, consistent with an immune-suppressive role for the gingipains. Our data show that the combination of an intact fimB allele and limited cell surface gingipain activity in P. gingivalis 381 renders this strain more immune-stimulatory. Conversely, a defective fimB allele and high-level cell surface gingipain activity reduce the capacity of P. gingivalis 33277 to stimulate host cell innate immune responses. In summary, genomic and transcriptomic comparisons identified key virulence characteristics that confer divergent host cell innate immune responses to these highly related P. gingivalis strains.


Assuntos
Proteínas de Fímbrias/genética , Proteínas de Fímbrias/imunologia , Porphyromonas gingivalis/genética , Porphyromonas gingivalis/imunologia , Infecções por Bacteroidaceae/imunologia , Infecções por Bacteroidaceae/microbiologia , Linhagem Celular Tumoral , Células HEK293 , Humanos , Imunidade Inata/genética , Imunidade Inata/imunologia , Interleucina-1beta/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Transdução de Sinais/imunologia , Células THP-1 , Receptor 2 Toll-Like/metabolismo
2.
Nutrients ; 11(9)2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31527555

RESUMO

BACKGROUND: Coffee is a major dietary source of polyphenols. Previous research found that coffee had a protective effect on periodontal disease. In this study, we aimed to investigate whether coffee extract and its primary phenolic acid, chlorogenic acid, affect the growth and protease activity of a periodontopathogen Porphyromonas gingivalis (P. gingivalis). METHODS: Coffee extract and chlorogenic acid were prepared by a two-fold serial dilution. The turbid metric test and plate count method were used to examine the inhibitory effects of chlorogenic acid on P. gingivalis. The time-kill assay was used to measure changes in the viability of P. gingivalis after exposure to chlorogenic acid for 0-24 h. The protease activity of P. gingivalis was analyzed using the optical density of a chromogenic substrate. RESULTS: As a result, the minimum inhibitory concentration (MIC) of chlorogenic acid was 4 mg/mL, and the minimum bactericidal concentration was 16 mg/mL. Chlorogenic acid at concentrations above MIC resulted in a longer-lasting inhibitory effect on P. gingivalis viability and significantly reduced associated protease activity. The coffee extract showed antibacterial activity as observed by the disk diffusion test, whereas these inhibitory effects were not affected by different roast degrees of coffee. CONCLUSIONS: Collectively, our novel findings indicate that chlorogenic acid not only has antimicrobial activity but also reduced the protease activity of P. gingivalis. In addition, coffee extract inhibits the proliferation of P. gingivalis, which may partly be attributed to the effect of chlorogenic acid.


Assuntos
Antibacterianos/farmacologia , Infecções por Bacteroidaceae/prevenção & controle , Ácido Clorogênico/farmacologia , Coffea/química , Periodontite/tratamento farmacológico , Extratos Vegetais/farmacologia , Porphyromonas gingivalis/efeitos dos fármacos , Antibacterianos/isolamento & purificação , Proteínas de Bactérias/metabolismo , Infecções por Bacteroidaceae/microbiologia , Ácido Clorogênico/isolamento & purificação , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Viabilidade Microbiana/efeitos dos fármacos , Peptídeo Hidrolases/metabolismo , Periodontite/microbiologia , Extratos Vegetais/isolamento & purificação , Porphyromonas gingivalis/enzimologia , Porphyromonas gingivalis/patogenicidade , Sementes/química , Fatores de Tempo , Fatores de Virulência/metabolismo
3.
Infect Immun ; 87(10)2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31331955

RESUMO

Porphyromonas gingivalis is considered a keystone pathogen that contributes to the initiation and progression of periodontitis in humans. P. gingivalis has also been detected in human placentas associated with adverse pregnancy outcomes. The spread of P. gingivalis from the oral cavity to the reproductive tract thus represents a potential mechanism whereby periodontitis can lead to adverse pregnancy outcomes. In a murine model of pregnancy and oral infection with P. gingivalis, C57BL/6J mice developed low fetal weight, whereas C57BL/6NCrl mice did not. Although C57BL/6NCrl mice harbor segmented filamentous bacteria that drive a Th17 response, fetal weight was independent of frequency of Th17 or Th1 in either substrain. Low fetal weight was instead correlated with increasing amounts of P. gingivalis DNA in the placentas of the C57BL/6J dams. In contrast, fetal weight in C57BL/6NCrl mice was independent of P. gingivalis in the placenta. Differences in genetics or microbiome that influence the ability of P. gingivalis to colonize the placenta may drive differential fetal weight outcomes between C57BL/6J and C57BL/6NCrl mice and, potentially, between diverse human populations.


Assuntos
Infecções por Bacteroidaceae/microbiologia , Peso Fetal , Periodontite/microbiologia , Porphyromonas gingivalis/patogenicidade , Complicações Infecciosas na Gravidez/microbiologia , Células Th17/microbiologia , Animais , Infecções por Bacteroidaceae/imunologia , Infecções por Bacteroidaceae/patologia , Modelos Animais de Doenças , Feminino , Feto , Expressão Gênica , Interferon gama/genética , Interferon gama/imunologia , Interleucina-17/genética , Interleucina-17/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Boca/imunologia , Boca/microbiologia , Periodontite/imunologia , Periodontite/patologia , Placenta/imunologia , Placenta/microbiologia , Porphyromonas gingivalis/imunologia , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/patologia , Especificidade da Espécie , Células Th17/imunologia
4.
Int J Mol Sci ; 20(14)2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31340425

RESUMO

The aim of this study was to perform a systematic review of the literature followed by a meta-analysis about the efficacy of photodynamic therapy (PDT) on the microorganisms responsible for dental caries. The research question and the keywords were constructed according to the PICO strategy. The article search was done in Embase, Lilacs, Scielo, Medline, Scopus, Cochrane Library, Web of Science, Science Direct, and Pubmed databases. Randomized clinical trials and in vitro studies were selected in the review. The study was conducted according the PRISMA guideline for systematic review. A total of 34 articles were included in the qualitative analysis and four articles were divided into two subgroups to perform the meta-analysis. Few studies have achieved an effective microbial reduction in microorganisms associated with the pathogenesis of dental caries. The results highlight that there is no consensus about the study protocols for PDT against cariogenic microorganisms, although the results showed the PDT could be a good alternative for the treatment of dental caries.


Assuntos
Infecções por Bacteroidaceae/tratamento farmacológico , Candidíase/tratamento farmacológico , Cárie Dentária/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Infecções Estreptocócicas/tratamento farmacológico , Infecções por Bacteroidaceae/microbiologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Candida/patogenicidade , Candidíase/microbiologia , Curcumina/farmacologia , Cárie Dentária/microbiologia , Humanos , Azul de Metileno/farmacologia , Porphyromonas gingivalis/efeitos dos fármacos , Porphyromonas gingivalis/crescimento & desenvolvimento , Porphyromonas gingivalis/patogenicidade , Corantes de Rosanilina/farmacologia , Infecções Estreptocócicas/microbiologia , Streptococcus/efeitos dos fármacos , Streptococcus/crescimento & desenvolvimento , Streptococcus/patogenicidade , Cloreto de Tolônio/farmacologia , Resultado do Tratamento
5.
Mediators Inflamm ; 2019: 7241312, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31341421

RESUMO

Porphyromonas gingivalis (P. gingivalis) and Fusobacterium nucleatum (F. nucleatum) are Gram-negative anaerobic bacteria possessing several virulence factors that make them potential pathogens associated with periodontal disease. Periodontal diseases are chronic inflammatory diseases of the oral cavity, including gingivitis and periodontitis. Periodontitis can lead to tooth loss and is considered one of the most prevalent diseases worldwide. P. gingivalis and F. nucleatum possess virulence factors that allow them to survive in hostile environments by selectively modulating the host's immune-inflammatory response, thereby creating major challenges to host cell survival. Studies have demonstrated that bacterial infection and the host immune responses are involved in the induction of periodontitis. The NLRP3 inflammasome and its effector molecules (IL-1ß and caspase-1) play roles in the development of periodontitis. We and others have reported that the purinergic P2X7 receptor plays a role in the modulation of periodontal disease and intracellular pathogen control. Caspase-4/5 (in humans) and caspase-11 (in mice) are important effectors for combating bacterial pathogens via mediation of cell death and IL-1ß release. The exact molecular events of the host's response to these bacteria are not fully understood. Here, we review innate and adaptive immune responses induced by P. gingivalis and F. nucleatum infections and discuss the possibility of manipulations of the immune response as therapeutic strategies. Given the global burden of periodontitis, it is important to develop therapeutic targets for the prophylaxis of periodontopathogen infections.


Assuntos
Infecções por Bacteroidaceae/microbiologia , Infecções por Fusobacterium/microbiologia , Fusobacterium nucleatum/patogenicidade , Doenças Periodontais/microbiologia , Porphyromonas gingivalis/patogenicidade , Imunidade Adaptativa , Animais , Infecções por Bacteroidaceae/terapia , Caspase 1/metabolismo , Sobrevivência Celular , Infecções por Fusobacterium/imunologia , Infecções por Fusobacterium/terapia , Humanos , Imunidade Inata , Inflamassomos , Inflamação , Interleucina-1beta/metabolismo , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Doenças Periodontais/imunologia , Doenças Periodontais/terapia , Virulência
6.
Int J Mol Sci ; 20(11)2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31167516

RESUMO

It has been suggested that Porphyromonas gingivalis (P. gingivalis), a keystone pathogen in chronic periodontitis, is associated with a variety of cancers, including oral cancer. Recently, studies have shown the effects of persistent exposure to P. gingivalis on the promotion of tumorigenic properties of oral epithelial cells, suggesting that chronic P. gingivalis infection is a potential risk factor for oral cancer. On the other hand, Fusobacterium nucleatum (F. nucleatum), one of the major periodontal pathogens, has emerged as an important factor in the colon cancer progression. Here, we investigated the diagnostic potential of serum immunoglobulin G antibody against periodontal pathogens, P. gingivalis and F. nucleatum, and serum IL-6 for oral squamous cell carcinoma (OSCC). An enzyme-linked immunosorbent assay (ELISA) was used to determine and compare the serum levels of interleukin 6 (IL-6), F. nucleatum IgG, and P. gingivalis IgG in 62 OSCC patients with 46 healthy controls. The serum levels of P. gingivalis IgG and IL-6 were higher in OSCC patients than in non-OSCC controls, and the difference was statistically significant. In addition, a high serum level of IL-6 was associated with a worse prognosis in OSCC patients. Thus, P. gingivalis IgG and IL-6 could be utilized as potential serum biomarkers for the diagnosis of OSCC, and the serum level of IL-6 contributes to improved prognostic performance.


Assuntos
Anticorpos Antibacterianos/imunologia , Biomarcadores , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/metabolismo , Interleucina-6/sangue , Neoplasias Bucais/etiologia , Neoplasias Bucais/metabolismo , Porphyromonas gingivalis/imunologia , Anticorpos Antibacterianos/sangue , Infecções por Bacteroidaceae/microbiologia , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Humanos , Neoplasias Bucais/mortalidade , Neoplasias Bucais/patologia , Curva ROC
7.
PLoS Pathog ; 15(5): e1007773, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31107907

RESUMO

Neutrophil-derived networks of DNA-composed extracellular fibers covered with antimicrobial molecules, referred to as neutrophil extracellular traps (NETs), are recognized as a physiological microbicidal mechanism of innate immunity. The formation of NETs is also classified as a model of a cell death called NETosis. Despite intensive research on the NETs formation in response to pathogens, the role of specific bacteria-derived virulence factors in this process, although postulated, is still poorly understood. The aim of our study was to determine the role of gingipains, cysteine proteases responsible for the virulence of P. gingivalis, on the NETosis process induced by this major periodontopathogen. We showed that NETosis triggered by P. gingivalis is gingipain dependent since in the stark contrast to the wild-type strain (W83) the gingipain-null mutant strain only slightly induced the NETs formation. Furthermore, the direct effect of proteases on NETosis was documented using purified gingipains. Notably, the induction of NETosis was dependent on the catalytic activity of gingipains, since proteolytically inactive forms of enzymes showed reduced ability to trigger the NETs formation. Mechanistically, gingipain-induced NETosis was dependent on proteolytic activation of protease-activated receptor-2 (PAR-2). Intriguingly, both P. gingivalis and purified Arg-specific gingipains (Rgp) induced NETs that not only lacked bactericidal activity but instead stimulated the growth of bacteria species otherwise susceptible to killing in NETs. This protection was executed by proteolysis of bactericidal components of NETs. Taken together, gingipains play a dual role in NETosis: they are the potent direct inducers of NETs formation but in the same time, their activity prevents P. gingivalis entrapment and subsequent killing. This may explain a paradox that despite the massive accumulation of neutrophils and NETs formation in periodontal pockets periodontal pathogens and associated pathobionts thrive in this environment.


Assuntos
Adesinas Bacterianas/imunologia , Infecções por Bacteroidaceae/imunologia , Cisteína Endopeptidases/imunologia , Armadilhas Extracelulares/imunologia , Neutrófilos/imunologia , Peritonite/imunologia , Porphyromonas gingivalis/imunologia , Porphyromonas gingivalis/patogenicidade , Receptor PAR-2/metabolismo , Adesinas Bacterianas/metabolismo , Animais , Infecções por Bacteroidaceae/metabolismo , Infecções por Bacteroidaceae/microbiologia , Infecções por Bacteroidaceae/patologia , Células Cultivadas , Cisteína Endopeptidases/metabolismo , Armadilhas Extracelulares/microbiologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/microbiologia , Neutrófilos/patologia , Peritonite/metabolismo , Peritonite/microbiologia , Receptor PAR-2/imunologia , Transdução de Sinais
8.
PLoS One ; 14(3): e0213309, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30870452

RESUMO

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, α5ß1 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.


Assuntos
Aderência Bacteriana , Infecções por Bacteroidaceae/microbiologia , Células Epiteliais/microbiologia , Fímbrias Bacterianas/microbiologia , Gengiva/microbiologia , Porphyromonas/isolamento & purificação , Células Epiteliais/citologia , Gengiva/citologia , Humanos , Integrina alfa5beta1/metabolismo
10.
APMIS ; 127(4): 187-195, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30861212

RESUMO

Periodontal disease is an oral inflammatory disease that destroys the tooth supporting periodontal tissues resulting in tooth loss. Porphyromonas gingivalis is a keystone pathogen that plays a significant role in periodontitis. In previous studies, resveratrol has shown significant results by targeting inflammatory and adhesive markers. Virulence factors of P. gingivalis play an important role in the bacterial adhesion and colonization. In this study, we aimed to demonstrate the anti-biofilm and anti-bacterial activity of resveratrol and also study the effect of resveratrol on the expression of virulence factor genes of P. gingivalis using reverse transcriptase polymerase chain reaction (RT-PCR). The anti-microbial and anti-biofilm activity of resveratrol on P. gingivalis was carried out by broth microdilution assay and biofilm adhesion reduction-crystal violet assay, respectively. We carried out the gene expression analysis by RT-PCR with the P. gingivalis treated compound to analyze the change in the expression of virulence factors: fimbriae and gingipain. Minimal inhibitory concentrations (MIC) of resveratrol against P. gingivalis and other clinical strains are in the range of 78.12-156.25 µg/mL. Resveratrol dose-dependently prevented the biofilm formation and also attenuated the virulence of P. gingivalis by reducing the expression of virulence factor genes such as fimbriae (type II and IV) and proteinases (kgp and rgpA). Resveratrol demonstrated superior anti-bacterial and anti-biofilm activity against P. gingivalis. There was significant reduction in the expression of fimbriae and gingipain with the resveratrol-treated compound. The results suggest that resveratrol, due to its multiple actions, may become a simple and inexpensive therapeutic strategy for treating periodontal disease.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Porphyromonas gingivalis/efeitos dos fármacos , Resveratrol/farmacologia , Fatores de Virulência/antagonistas & inibidores , Adesinas Bacterianas/análise , Infecções por Bacteroidaceae/microbiologia , Cisteína Endopeptidases/análise , Proteínas de Fímbrias/análise , Perfilação da Expressão Gênica , Violeta Genciana/análise , Humanos , Testes de Sensibilidade Microbiana , Doenças Periodontais/microbiologia , Porphyromonas gingivalis/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Coloração e Rotulagem
11.
Clin Microbiol Infect ; 25(9): 1156.e9-1156.e13, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30802650

RESUMO

OBJECTIVES: The prevalence of resistance genes in two important anaerobic genera, Bacteroides and Prevotella, was assessed by applying PCR specifically directed to genes of interest. METHODS: A total of 101 Bacteroides spp. and 99 Prevotella spp. human clinical isolates were identified using MALDI-TOF MS. The presence of the resistance genes cfxA, cepA, cfiA, tetQ, ermF and nim, was assessed. Prevalence of resistance genes was compared with the phenotypic resistance against amoxicillin, clindamycin, meropenem and metronidazole. RESULTS: Even though the majority of the Bacteroides isolates (95.0%) showed resistance towards amoxicillin, only 52/101 of the isolates harboured one of the resistance genes, accounting for this resistance. Within the genus Prevotella the presence of cfxA (50/99) almost perfectly matched the amoxicillin resistance (48/99). No difference in prevalence of the ermF gene (16/101 and 9/99) and clindamycin resistance (16/101 and 10/99) was observed within Bacteroides and Prevotella, respectively. Two isolates of Prevotella were resistant to metronidazole. One harboured the nim gene. One metronidazole-susceptible isolate of Bacteroides harboured a nim gene. Within the Bacteroides and Prevotella genera, 6/101 strains and 5/99 isolates harboured three different resistance genes, respectively, among them tetQ. TetQ is often located on a conjugative transposon, increasing the chance of horizontal gene transfer between isolates. CONCLUSIONS: An unknown mechanism in Bacteroides non-fragilis isolates causes resistance to ß-lactam antibiotics. The fact that the prevalence of the tetQ gene among Prevotella is increasing and the existence of isolates harbouring three resistance genes are worrisome developments.


Assuntos
Bacteroides/genética , Farmacorresistência Bacteriana/genética , Prevotella/genética , Antibacterianos/farmacologia , Infecções por Bacteroidaceae/epidemiologia , Infecções por Bacteroidaceae/microbiologia , Bacteroides/efeitos dos fármacos , Bacteroides/isolamento & purificação , Genes Bacterianos/genética , Humanos , Testes de Sensibilidade Microbiana , Países Baixos/epidemiologia , Prevalência , Prevotella/efeitos dos fármacos , Prevotella/isolamento & purificação
12.
Infect Immun ; 87(4)2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30670550

RESUMO

Although the periodontal pathogen Porphyromonas gingivalis must withstand high levels of nitrosative stress while in the oral cavity, the mechanisms of nitrosative stress defense are not well understood in this organism. Previously we showed that the transcriptional regulator HcpR plays a significant role in defense, and here we further defined its regulon. Our study shows that hcp (PG0893), a putative nitric oxide (NO) reductase, is the only gene significantly upregulated in response to nitrite (NO2) and that this regulation is dependent on HcpR. An isogenic mutant deficient in hcp is not able to grow with 200 µM nitrite, demonstrating that the sensitivity of the HcpR mutant is mediated through Hcp. We further define the molecular mechanisms of HcpR interaction with the hcp promoter through mutational analysis of the inverted repeat present within the promoter. Although other putative nitrosative stress protection mechanisms present on the nrfAH operon are also found in the P. gingivalis genome, we show that their gene products play no role in growth of the bacterium with nitrite. As growth of the hcp-deficient strain was also significantly diminished in the presence of a nitric oxide-producing compound, S-nitrosoglutathione (GSNO), Hcp appears to be the primary means by which P. gingivalis responds to NO2 --based stress. Finally, we show that Hcp is required for survival with host cells but that loss of Hcp has no effect on association and entry of P. gingivalis into human oral keratinocytes.


Assuntos
Proteínas de Bactérias/metabolismo , Infecções por Bacteroidaceae/microbiologia , Nitritos/metabolismo , Oxirredutases/metabolismo , Porphyromonas gingivalis/enzimologia , Porphyromonas gingivalis/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Humanos , Viabilidade Microbiana , Óperon , Oxirredutases/genética , Porphyromonas gingivalis/genética , Porphyromonas gingivalis/metabolismo
13.
Folia Microbiol (Praha) ; 64(4): 555-566, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30656591

RESUMO

Candida albicans can enhance the invasion of oral epithelial cells by Porphyromonas gingivalis, although the fungus is not a periodontal pathogen. In this study, we investigated whether C. albicans augments proinflammatory cytokine production by mouse macrophage-like J774.1 cells incubated with synthetic bacterial components. Mouse macrophage-like J774.1 cells, mouse primary splenocytes, human THP-1 cells, and A549 cells were pretreated with or without heat-killed C. albicans (HKCA) or substitutes for C. albicans cell wall components in 96-well flat-bottomed plates. Cells were then washed and incubated with Pam3CSK4, a Toll-like receptor (TLR) 2 ligand, or lipid A, a TLR4 ligand. Culture supernatants were analyzed by ELISA for secreted IL-6, MCP-1, TNF-α, and IL-8. HKCA augmented TLR ligand-induced proinflammatory cytokine production by J774.1 cells, mouse splenocytes, and THP-1 cells, but not A549 cells. However, IL-6, MCP-1, and TNF-α production induced by Pam3CSK4 or lipid A was not augmented when cells were pretreated with curdlan, a dectin-1 ligand, or mannan, a dectin-2 ligand. In contrast, pretreatment of cells with TLR ligands upregulated the production of IL-6 and TNF-α, but not MCP-1, induced by Pam3CSK4 or lipid A. The results suggest that C. albicans augments synthetic bacterial component-induced cytokine production by J774.1 cells via the TLR pathway, but not the dectin-1 or dectin-2 pathway.


Assuntos
Infecções por Bacteroidaceae/imunologia , Candida albicans/fisiologia , Citocinas/imunologia , Animais , Infecções por Bacteroidaceae/genética , Infecções por Bacteroidaceae/microbiologia , Candida albicans/química , Linhagem Celular , Citocinas/genética , Temperatura Alta , Humanos , Interleucina-6/genética , Interleucina-6/imunologia , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Macrófagos/imunologia , Macrófagos/microbiologia , Camundongos , Porphyromonas gingivalis/química , Porphyromonas gingivalis/fisiologia , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
14.
Int J Mol Med ; 43(3): 1430-1440, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30664173

RESUMO

Porphyromonas gingivalis (P. gingivalis) is a periodontal pathogen that may accumulate with other organisms in subgingival plaque biofilms and is associated with periodontal disease. P. gingivalis fimbriae (FimA) is a filamentous structure on the surface of bacteria that is closely associated with bacterial adhesion to and colonization of host tissues, and serves an essential role in biofilm formation. The present study aimed to construct P. gingivalis FimA prokaryotic expression plasmids, purify a FimA fusion protein and explore the effect of a recombinant FimA protein on the inflammatory response in human peripheral blood mononuclear cells (PBMCs). P. gingivalis FimA prokaryotic expression plasmids were constructed by gene cloning and recombination technology. SDS­PAGE was used to evaluate the purified recombinant FimA protein. The cell proliferation rate and inflammatory cytokine expression of PBMCs treated with the FimA fusion protein with or without transfection with toll­like receptor 4 (TLR4) small interfering (si)RNA were detected by CCK­8 assays and ELISAs, respectively. The expression levels of TLR4, nuclear factor kappa­light­chain­enhancer of activated B cells (NF­κB) and myeloid differentiation primary response 88 (MyD88) in PBMCs were detected by western blot analysis and reverse transcription quantitative polymerase chain reaction. A FimA fusion protein with high purity was obtained. FimA fusion protein treatment significantly increased PBMC proliferation and promoted the release of tumor necrosis factor­α (TNF­α), interleukin (IL)­6, matrix metalloproteinase (MMP)­8 and MMP­9 in PBMCs. TLR4 interference reversed the effects of the FimA fusion protein on PBMC proliferation and inflammatory cytokine release. The expression levels of TLR4, NF­κB and MyD88 in PBMCs were significantly increased following treatment with the FimA fusion protein, while the expression levels of these genes at the mRNA and protein levels decreased significantly in PBMCs following FimA fusion protein treatment and TLR4 interference. The FimA fusion protein increased PBMC proliferation and promoted the release of the inflammatory cytokines TNF­α, IL­6, MMP­8 and MMP­9 via the TLR4/NF­κB signaling pathway. FimA may serve as a promising therapeutic strategy for periodontal disease.


Assuntos
Proteínas de Fímbrias/efeitos adversos , Inflamação/etiologia , Inflamação/metabolismo , NF-kappa B/metabolismo , Porphyromonas gingivalis/metabolismo , Proteínas Recombinantes/efeitos adversos , Receptor 4 Toll-Like/metabolismo , Adulto , Infecções por Bacteroidaceae/metabolismo , Infecções por Bacteroidaceae/microbiologia , Clonagem Molecular , Citocinas/metabolismo , Proteínas de Fímbrias/genética , Proteínas de Fímbrias/metabolismo , Proteínas de Fímbrias/farmacologia , Expressão Gênica , Humanos , Mediadores da Inflamação/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Porphyromonas gingivalis/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia
15.
Cytokine ; 113: 89-98, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29937409

RESUMO

This study aims to explore a relationship between exposures of whole-cell Porphyromonas gingivalis in various doses with atopic inflammatory responses at experimental mice. A pretest-posttest controlled group design, with 16 Wistar rats (Rattus novergicus) randomized into four groups. Group 1 was the control group. Group 2 was given low-dose (9 × 107 colony-forming unit) of P. gingivalis. Group 3 was given medium-dose (9 × 109 colony-forming unit) of P. gingivalis. Group 4 was given high-dose (9 × 1011 colony-forming unit) of P. gingivalis. Interleukin-4, Interleukin-5, Interleukin-17F, Interleukin-21, Immunoglobulin-E, Immunoglobulin-G4, and γ-Interferon were measured by direct-sandwich ELISA just before the treatments began, day-4, and day-11 after treatments. There is a sudden increase of Interleukin-4 in the group 4 (23.79 ±â€¯0.91 pg/ml to 54.17 ±â€¯0.79 pg/ml; p = 0.01) and slight increase of Interleukin-5 in the group 4 (207.60 ±â€¯11.15 pg/ml to 243.40 ±â€¯9.33 pg/ml; p = 0.03). No change was observed for Interleukin-17F in all groups. Serum concentration of Immunoglobulin-E was decreased in group 2 (-10.44 ±â€¯8.13 pg/ml), but increased in group 4 (+1.03 ±â€¯4.57 pg/ml). Taken together, some cytokines are up-regulated and others are down-regulated after exposure to whole-cell P. gingivalis. Moreover, study of host responses during periodontal infection may offer critical key insight that contribute to the development of atopy. CLINICAL IMPLICATIONS: We introduced and explained the potential role of periodontal pathogen Porphyromonas gingivalis in systemic immune responses, along with its virulence factor inside the oral cavity. Our results consider several changes and differences of cytokines and immunoglobulins following whole-cell Porphyromonas gingivalis exposure. However, results of the study need to be interpreted with caution due to its limitations. CAPSULE SUMMARY: Interleukin (IL)-4 and IL-5 had been found increase after exposure to the periodontal pathogens Porphyromonas gingivalis, whereas no or minimal change had been found in the level of IL-17F, Ig-G4, and IFN-γ. The various cytokines and immunoglobulins shown in this study do not prove a causal relationship, and the precise role of Porphyromonas gingivalis in the regulation of atopic immune response warrants further investigation. Nevertheless, these findings may provide some critical key insight into the host responses following Porphyromonas gingivalis infection.


Assuntos
Hipersensibilidade/imunologia , Periodontite/imunologia , Animais , Infecções por Bacteroidaceae/imunologia , Infecções por Bacteroidaceae/microbiologia , Citocinas/imunologia , Regulação para Baixo/imunologia , Hipersensibilidade/microbiologia , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Masculino , Camundongos , Boca/imunologia , Boca/microbiologia , Periodontite/microbiologia , Porphyromonas gingivalis/imunologia , Ratos , Ratos Wistar , Regulação para Cima/imunologia
16.
Sci Rep ; 8(1): 17679, 2018 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-30518941

RESUMO

Perinatal HIV infection is characterized by faster HIV disease progression and higher initial rate of HIV replication compared to adults. While antiretroviral therapy (ART) has greatly reduced HIV replication to undetectable levels, there is persistent elevated inflammation associated with HIV disease progression. Alteration of gut microbiota is associated with increased inflammation in chronic adult HIV infection. Here, we aim to study the gut microbiome and its role in inflammation in treated and untreated HIV-infected children. Examination of fecal microbiota revealed that perinatally infected children living with HIV had significantly higher levels of genus Prevotella that persisted despite ART. These children also had higher levels of soluble CD14 (sCD14), a marker of microbial translocation, and IP-10 despite therapy. The Prevotella positively correlated with IP-10 levels in both treated and untreated HIV-infected children, while genus Prevotella and species Prevotella copri was inversely associated with CD4 count. Relative abundance of genus Prevotella and species Prevotella copri showed positive correlation with sCD14 in ART-suppressed perinatally HIV-infected children. Our study suggests that gut microbiota may serve as one of the driving forces behind the persistent inflammation in children despite ART. Reshaping of microbiota using probiotics may be recommended as an adjunctive therapy along with ART.


Assuntos
Terapia Antirretroviral de Alta Atividade , Quimiocina CXCL10/sangue , Microbioma Gastrointestinal , Infecções por HIV/tratamento farmacológico , Infecções por HIV/microbiologia , Prevotella/isolamento & purificação , Translocação Bacteriana/efeitos dos fármacos , Infecções por Bacteroidaceae/sangue , Infecções por Bacteroidaceae/microbiologia , Contagem de Linfócito CD4 , Criança , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Infecções por HIV/sangue , Humanos , Masculino , Prevotella/efeitos dos fármacos
17.
Anaerobe ; 54: 197-200, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30541687

RESUMO

Despite the wide implementation of MALDI-TOF MS for the rapid and reliable identification of most microorganisms, some taxonomic groups such as the Porphyromonas genus remain largely untested. In this study we evaluated the performance of MALDI-TOF MS on this genus using a collection of 39 isolates sent for routine identification to our institution over a 16-year period. All of them were identified by DNA-sequencing analysis of the 16S rRNA gene plus the hsp60 gene when the previous one did not yield species-level assignment. MALDI-TOF MS provided correct identification at least at the genus level of 21/39 isolates (53.9%). Twelve isolates were correctly identified at the species level with a score value ≥ 2.0 and 9 more with score values < 2.0 and ≥ 1.7. The species most represented in the database (P. gingivalis and P. somerae) lay within this category. However, the species poorly represented in this database (P. asaccharolytica and P. uenonis) were mostly identified with lower scores (1.35-1.67) or remained unidentified by MALDI-TOF MS. The addition of two P. asaccharolytica reference spectra to our in-house library allowed 72.9% of genus-level identifications with 17/37 isolates (45.9%) identified with score values ≥ 2.0. Our results showed a high level of correlation between MALDI-TOF MS and DNA-based identification for Porphyromonas spp. strains at the species level, even with score values < 2.0. The reliability provided by MALDI-TOF MS increased when the database was fed with spectra from the species poorly represented in the commercial database.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Infecções por Bacteroidaceae/microbiologia , Testes Diagnósticos de Rotina/métodos , Porphyromonas/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Infecções por Bacteroidaceae/diagnóstico , DNA Bacteriano/genética , Humanos , Porphyromonas/química , Porphyromonas/classificação , Porphyromonas/genética , RNA Ribossômico 16S/genética
18.
Future Microbiol ; 13: 1585-1601, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30430852

RESUMO

AIM: To evaluate the antibacterial activity of 12 kaurane-type diterpenes against a panel of bacteria that cause endodontic infection. METHODS & MATERIALS: We conducted tests against bacteria in the planktonic or in the sessile mode, cytotoxic assays for the most promising compounds against human normal lung fibroblast cells, and Porphyromonas gingivalis (ATCC 33277) proteomic analysis. RESULTS & CONCLUSION: Kaurenoic acid and its salt exhibited satisfactory antibacterial action against the evaluated bacteria. Proteomic analysis suggested that these compounds might interfere in bacterial metabolism and virulence factor expression. Kaurane-type diterpenes are an important class of natural products and should be considered in the search for new irrigating solutions to treat endodontic infections.


Assuntos
Antibacterianos/farmacologia , Infecções por Bacteroidaceae/tratamento farmacológico , Diterpenos/farmacologia , Porphyromonas gingivalis/efeitos dos fármacos , Antibacterianos/química , Infecções por Bacteroidaceae/microbiologia , Biofilmes/efeitos dos fármacos , Diterpenos/química , Humanos , Viabilidade Microbiana/efeitos dos fármacos , Mikania/química , Extratos Vegetais/química , Folhas de Planta/química , Porphyromonas gingivalis/crescimento & desenvolvimento , Porphyromonas gingivalis/isolamento & purificação , Pulpite/tratamento farmacológico , Pulpite/microbiologia
19.
Sci Rep ; 8(1): 16607, 2018 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-30413788

RESUMO

Chronic periodontitis (CP) is a microbial dysbiotic disease linked to increased risk of oral squamous cell carcinomas (OSCCs). To address the underlying mechanisms, mouse and human cell infection models and human biopsy samples were employed. We show that the 'keystone' pathogen Porphyromonas gingivalis, disrupts immune surveillance by generating myeloid-derived dendritic suppressor cells (MDDSCs) from monocytes. MDDSCs inhibit CTLs and induce FOXP3 + Tregs through an anti-apoptotic pathway. This pathway, involving pAKT1, pFOXO1, FOXP3, IDO1 and BIM, is activated in humans with CP and in mice orally infected with Mfa1 expressing P. gingivalis strains. Mechanistically, activation of this pathway, demonstrating FOXP3 as a direct FOXO1-target gene, was demonstrated by ChIP-assay in human CP gingiva. Expression of oncogenic but not tumor suppressor markers is consistent with tumor cell proliferation demonstrated in OSCC-P. gingivalis cocultures. Importantly, FimA + P. gingivalis strain MFI invades OSCCs, inducing inflammatory/angiogenic/oncogenic proteins stimulating OSCCs proliferation through CXCR4. Inhibition of CXCR4 abolished Pg-MFI-induced OSCCs proliferation and reduced expression of oncogenic proteins SDF-1/CXCR4, plus pAKT1-pFOXO1. Conclusively, P. gingivalis, through Mfa1 and FimA fimbriae, promotes immunosuppression and oncogenic cell proliferation, respectively, through a two-hit receptor-ligand process involving DC-SIGN+hi/CXCR4+hi, activating a pAKT+hipFOXO1+hiBIM-lowFOXP3+hi and IDO+hi- driven pathway, likely to impact the prognosis of oral cancers in patients with periodontitis.


Assuntos
Apoptose , Infecções por Bacteroidaceae/imunologia , Carcinogênese/patologia , Células Dendríticas/imunologia , Imunossupressão , Monócitos/imunologia , Periodontite/imunologia , Animais , Infecções por Bacteroidaceae/microbiologia , Infecções por Bacteroidaceae/patologia , Carcinogênese/imunologia , Estudos de Casos e Controles , Proliferação de Células , Células Dendríticas/microbiologia , Células Dendríticas/patologia , Gengiva/imunologia , Gengiva/microbiologia , Gengiva/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/microbiologia , Monócitos/patologia , Periodontite/microbiologia , Periodontite/patologia , Porphyromonas gingivalis/imunologia
20.
JNMA J Nepal Med Assoc ; 56(212): 781-786, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30387469

RESUMO

INTRODUCTION: Chronic periodontitis is an infectious disease. Porphyromonas gingivalis is the major pathogen associated with it and can be found in all ecosystems in the oral cavity. The presence of this organism is highly correlated with preterm and low birth weight babies. So, this study aimed to assess vertical transmission of P.gingivalis from pregnant women to their new born. METHODS: Forty six pregnant women with chronic periodontitis were recruited for this cross-sectional study. Whole unstimulated saliva was collected from them before delivery and from their new-borns within forty eight hours of birth. Quantification of P.gingivalis in the saliva samples was carried out by quantitative real time polymerase chain reaction. The obtained data were analysed by SPSS 16 program. RESULTS: The results showed a significant correlation (P=0.002) between the number of P.gingivalis present in the mother's saliva with that of the new-borns' saliva. DNA copies of more than 5000/µl of P.gingivalis was found in 20 (43.5%) maternal saliva and 21 (45.7%) in new-borns' saliva. Both Plaque index and Extent and Severity index showed no correlation (P>0.05) with DNA copies of P.gingivalis in new-borns' saliva. CONCLUSIONS: The DNA copies of P.gingivalis found in new-borns' saliva are in par with mother saliva, as the saliva sample obtained from new-borns' were within forty eight hours of birth, no other environmental factor can have a direct role in its transmission. Thus, it can be concluded that P.gingivalis is vertically transmitted from mother to child.


Assuntos
Infecções por Bacteroidaceae/transmissão , Transmissão Vertical de Doença Infecciosa , Porphyromonas gingivalis , Saliva/microbiologia , Adolescente , Adulto , Infecções por Bacteroidaceae/microbiologia , Periodontite Crônica/complicações , Periodontite Crônica/microbiologia , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/microbiologia , Adulto Jovem
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