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OBJECTIVE: This study aimed to evaluate the effects of ingested periodontal pathogens on experimental colitis in mice and to elucidate its underlying mechanisms. BACKGROUND: Inflammatory bowel disease (IBD) is defined as a chronic intestinal inflammation that results in damage to the gastrointestinal tract. Epidemiological studies have shown an association between IBD and periodontitis. Although a large number of ingested oral bacteria reach gastrointestinal tract constantly, the effect of ingested periodontal pathogens on intestinal inflammation is still unknown. METHODS: Experimental colitis was induced by inclusion of dextran sodium sulfate solution in drinking water of the mice. Major periodontal pathogens (Porphyromonas gingivalis, Prevotella intermedia, and Fusobacterium nucleatum) were administered orally every day during the experiment. The severity of colitis between the groups was compared. In vitro studies of the intestinal epithelial cell line were conducted to explore the molecular mechanisms by which periodontal pathogens affect the development of colitis. RESULTS: The oral administration of P. gingivalis significantly increased the severity of colitis when compared to other pathogens in the DSS-induced colitis model. The ingested P. gingivalis disrupted the colonic epithelial barrier by decreasing the expression of tight junction proteins in vivo. In vitro permeability assays using the intestinal epithelial cell line suggested the P. gingivalis-specific epithelial barrier disruption. The possible involvement of gingipains in the exacerbation of colitis was implied by using P. gingivalis lacking gingipains. CONCLUSION: Porphyromonas gingivalis exacerbates gastrointestinal inflammation by directly interacting with the intestinal epithelial barrier in a susceptible host.
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Colite , Porphyromonas gingivalis , Animais , Colite/induzido quimicamente , Colite/complicações , Ingestão de Alimentos , Fusobacterium nucleatum , Camundongos , Camundongos Endogâmicos C57BL , Prevotella intermediaRESUMO
BACKGROUND AND OBJECTIVES: Recent evidence suggests that oral bacteria can affect extra-oral diseases by modulating aspects of the gut environment such as the microbiome, metabolome, and immune profiles. However, differences in the effects of different types of oral bacteria, particularly periodontopathic and health-associated bacteria, remain elusive. MATERIALS AND METHODS: Five-week-old germ-free mice were orally administered with either periodontopathic bacteria as oral pathobionts (Porphyromonas gingivalis, Filifactor alocis, and Fusobacterium nucleatum) or bacteria associated with periodontal health (Actinomyces naeslundii, Streptococcus mitis, and Veillonella rogosae) twice a week for five weeks. The presence of all bacterial species in the feces and the livers of the mice was analyzed via polymerase chain reaction (PCR), using specific primers for 16S rRNA genes. Alveolar bone resorption was evaluated histologically. The expression profiles of various genes in the liver and small intestine were analyzed using real-time PCR. Sera were analyzed to determine the levels of antibodies and endotoxin. The proportions of T helper 17 (Th17) and regulatory T (Treg) cells in mesenteric lymph nodes and Peyer's patches were analyzed using flow cytometry. RESULTS: Neither of the types of bacteria administered in this experiment induced alveolar bone resorption. All bacteria elicited some degree of systemic antibody response in the mice, although the response to S. mitis was not obvious. The response to P. gingivalis and V. rogosae was strongest. Generally, the health-associated bacteria but not the periodontitis-associated bacteria were detected in fecal samples. Interestingly, only Fusobacterium nucleatum DNA was detected in the liver, despite that live Fusobacterium nucleatum were not detected in the liver. The levels of interleukin-17 in the intestine and genes related to lipid accumulation in the liver were significantly higher in the mice that received periodontitis-associated bacteria. In addition, expression of the gene associated with endoplasmic reticulum stress was higher and that of the gene controlling circadian rhythm was lower in the periodontitis group. There was no difference in serum endotoxin, T-cell phenotypes in the lymphatic tissues, or genes related to the gut barrier. CONCLUSION: Oral administration of periodontitis-associated bacteria can induce pathological changes in the liver and intestine that are implicated in the process of periodontitis. These findings further support the importance of the oral-gut connection.
Assuntos
Boca/microbiologia , Periodontite/microbiologia , Simbiose , Actinomyces/fisiologia , Animais , Clostridiales/fisiologia , Feminino , Fusobacterium nucleatum/fisiologia , Vida Livre de Germes , Humanos , Interleucina-17/genética , Interleucina-17/imunologia , Intestinos/imunologia , Fígado/imunologia , Linfonodos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Periodontite/genética , Periodontite/imunologia , Porphyromonas gingivalis/fisiologia , Streptococcus mitis/fisiologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Veillonella/fisiologiaRESUMO
BACKGROUND: Gut microbiota plays a pivotal role in regulating host metabolism that affects the systemic health. To date, several studies have confirmed the fact that microbiota interacts with host, modulating immunity, controlling the homeostasis environment, and maintaining systemic condition. Recent studies have focused on the protective function of poly unsaturated fatty acids, 10-oxo-trans-11-oxadecenoic acid (KetoC) and 10-hydroxy-cis-12-octadecenoic acid (HYA), generated by gut microbiota on periodontal disease. Nevertheless, the mechanism remains unclear as investigations are limited to in vivo and in vitro studies. In this present review, we found that the administration of metabolites, KetoC and HYA, by a probiotic gut microbiota Lactobacillus plantarum from linoleic acid is found to inhibit the oxidation process, possess an antimicrobial function, and prevent the inflammation. These findings suggest the promising use of functional lipids for human health. CONCLUSION: Protective modalities of bioactive metabolites may support periodontal therapy by suppressing bacterial dysbiosis and regulating periodontal homeostasis in the clinical setting.
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Produtos Biológicos/farmacologia , Lactobacillus/metabolismo , Periodonto/efeitos dos fármacos , Produtos Biológicos/química , Ácidos Graxos Insaturados/metabolismo , Humanos , Estrutura Molecular , Higiene Bucal , Doenças Periodontais/tratamento farmacológico , Doenças Periodontais/etiologia , Metabolismo SecundárioRESUMO
BACKGROUND AND OBJECTIVES: We recently proposed a novel mechanism linking periodontitis and systemic diseases, in which orally administered Porphyromonas gingivalis affects gut microbiota composition and subsequently leads to systemic inflammation. However, the mechanism by which P. gingivalis generates systemic effects from the gut is unknown. MATERIAL AND METHODS: Six-week-old germ-free mice were orally administered with either an oral pathobiont P. gingivalis or an oral commensal Lactobacillus salivarius twice a week for 5 weeks. Control mice were administered with vehicle only. Alveolar bone resorption was evaluated histologically. The expression profile of various genes was analyzed in gingival tissue, liver, small intestine and large intestine using real-time polymerase chain reaction. Sera were analyzed for antibody, endotoxin and interleukin (IL)-6 levels. Antibody levels were also analyzed for culture supernatant of cells from mesenteric lymph nodes and spleens. A proportion of T-helper 17 and Treg in the cells from mesenteric lymph nodes and spleens was analyzed by flow cytometry. The level of IL-6 and IL-17 in the cell culture supernatants was analyzed by enzyme-linked immunosorbent assay. RESULTS: P. gingivalis administration did not induce alveolar bone resorption. Although P. gingivalis elicited systemic antibody response in germ-free mice, unlike in specific pathogen-free mice, P. gingivalis did not induce an inflammatory response in gingiva, liver and intestinal tissue, or alter the proportion of T-helper 17 and Treg. However, IL-6 and IL-17 productions were significantly elevated and tended to be elevated, respectively, in the cells from mesenteric lymph nodes of P. gingivalis-administered mice. Interestingly, the expression of IL-10 and tight junction protein in the gingiva and intestine, respectively, was significantly upregulated in P. gingivalis-treated mice. Administration of L. salivarius elicited almost similar effects as P. gingivalis. CONCLUSION: The oral pathobiont P. gingivalis did not induce any detectable pathogenic changes or any major host responses when administered to germ-free mice. There may be indirect mechanisms for gut-mediated systemic effects by P. gingivalis.
Assuntos
Ligilactobacillus salivarius , Porphyromonas gingivalis , Perda do Osso Alveolar/patologia , Animais , Formação de Anticorpos , Microbioma Gastrointestinal , Vida Livre de Germes , Gengiva/metabolismo , Gengiva/patologia , Inflamação/patologia , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Interleucina-6/metabolismo , Mucosa Intestinal/metabolismo , Fígado/patologia , Linfonodos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Baço/patologia , Linfócitos T Reguladores , Células Th17 , Proteínas de Junções Íntimas/metabolismoRESUMO
BACKGROUND: A variety of systemic diseases and conditions can affect the course of periodontitis or have a negative impact on the periodontal attachment apparatus. Gingival recessions are highly prevalent and often associated with hypersensitivity, the development of caries and non-carious cervical lesions on the exposed root surface and impaired esthetics. Occlusal forces can result in injury of teeth and periodontal attachment apparatus. Several developmental or acquired conditions associated with teeth or prostheses may predispose to diseases of the periodontium. The aim of this working group was to review and update the 1999 classification with regard to these diseases and conditions, and to develop case definitions and diagnostic considerations. METHODS: Discussions were informed by four reviews on 1) periodontal manifestions of systemic diseases and conditions; 2) mucogingival conditions around natural teeth; 3) traumatic occlusal forces and occlusal trauma; and 4) dental prostheses and tooth related factors. This consensus report is based on the results of these reviews and on expert opinion of the participants. RESULTS: Key findings included the following: 1) there are mainly rare systemic conditions (such as Papillon-Lefevre Syndrome, leucocyte adhesion deficiency, and others) with a major effect on the course of periodontitis and more common conditions (such as diabetes mellitus) with variable effects, as well as conditions affecting the periodontal apparatus independently of dental plaque biofilm-induced inflammation (such as neoplastic diseases); 2) diabetes-associated periodontitis should not be regarded as a distinct diagnosis, but diabetes should be recognized as an important modifying factor and included in a clinical diagnosis of periodontitis as a descriptor; 3) likewise, tobacco smoking - now considered a dependence to nicotine and a chronic relapsing medical disorder with major adverse effects on the periodontal supporting tissues - is an important modifier to be included in a clinical diagnosis of periodontitis as a descriptor; 4) the importance of the gingival phenotype, encompassing gingival thickness and width in the context of mucogingival conditions, is recognized and a novel classification for gingival recessions is introduced; 5) there is no evidence that traumatic occlusal forces lead to periodontal attachment loss, non-carious cervical lesions, or gingival recessions; 6) traumatic occlusal forces lead to adaptive mobility in teeth with normal support, whereas they lead to progressive mobility in teeth with reduced support, usually requiring splinting; 7) the term biologic width is replaced by supracrestal tissue attachment consisting of junctional epithelium and supracrestal connective tissue; 8) infringement of restorative margins within the supracrestal connective tissue attachment is associated with inflammation and/or loss of periodontal supporting tissue. However, it is not evident whether the negative effects on the periodontium are caused by dental plaque biofilm, trauma, toxicity of dental materials or a combination of these factors; 9) tooth anatomical factors are related to dental plaque biofilm-induced gingival inflammation and loss of periodontal supporting tissues. CONCLUSION: An updated classification of the periodontal manifestations and conditions affecting the course of periodontitis and the periodontal attachment apparatus, as well as of developmental and acquired conditions, is introduced. Case definitions and diagnostic considerations are also presented.
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Placa Dentária , Gengivite , Doenças Periodontais , Periodontite , Consenso , Estética Dentária , HumanosRESUMO
Sitafloxacin (STFX) is a newly developed quinolone that has robust antimicrobial activity against periodontopathic bacteria. We previously reported that oral administration of STFX during supportive periodontal therapy was as effective as conventional mechanical debridement under local anesthesia microbiologically and clinically for 3 months. The aim of the present study was to examine the short-term and long-term microbiological and clinical effects of systemic STFX and azithromycin (AZM) on active periodontal pockets during supportive periodontal therapy. Fifty-one patients receiving supportive periodontal therapy were randomly allocated to the STFX group (200 mg/day of STFX for 5 days) or the AZM group (500 mg/day of AZM for 3 days). The microbiological and clinical parameters were examined until 12 months after the systemic administration of each drug. The concentration of each drug in periodontal pockets and the antimicrobial susceptibility of clinical isolates were also analyzed. The proportions of red complex bacteria, i.e., Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia, which are the representative periodontopathic bacteria, were significantly reduced at 1 month and remained lower at 12 months than those at baseline in both the STFX and AZM groups. Clinical parameters were significantly improved over the 12-month period in both groups. An increase in the MIC of AZM against clinical isolates was observed in the AZM group. These results indicate that monotherapy with systemic STFX and AZM might be an alternative treatment during supportive periodontal therapy in patients for whom invasive mechanical treatment is inappropriate. (This study has been registered with the University Hospital Medical Information Network-Clinical Trials Registry [UMIN-CTR] under registration number UMIN000007834.).
Assuntos
Antibacterianos/uso terapêutico , Azitromicina/uso terapêutico , Fluoroquinolonas/uso terapêutico , Periodontite/tratamento farmacológico , Periodonto/microbiologia , Administração Oral , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Bolsa Periodontal/tratamento farmacológico , Periodontite/microbiologia , Periodonto/patologia , Porphyromonas gingivalis/efeitos dos fármacos , Porphyromonas gingivalis/isolamento & purificação , Tannerella forsythia/efeitos dos fármacos , Tannerella forsythia/isolamento & purificação , Treponema denticola/efeitos dos fármacos , Treponema denticola/isolamento & purificaçãoRESUMO
BACKGROUND: Periodontitis has been implicated as a risk factor for metabolic disorders associated with insulin resistance. Recently, we have demonstrated that orally administered Porphyromonas gingivalis, a representative periodontopathic bacterium, induces endotoxemia via reduced gut barrier function coupled with changes in gut microbiota composition, resulting in systemic inflammation and insulin resistance. Propolis, a resinous substance collected by honeybees from leaf buds and cracks in the bark of various plants, can positively affect metabolic disorders in various experimental models. In this study, we thus aimed to clarify the effect of propolis on impaired glucose and lipid metabolism induced by P. gingivalis administration. METHODS: Eight-week-old male C57BL/6 mice were orally administered P. gingivalis strain W83, propolis ethanol extract powder with P. gingivalis, or vehicle. We then analyzed the expression profile of glucose and lipid metabolism-related genes in the liver and adipose tissues. Serum endotoxin levels were also evaluated by a limulus amebocyte lysate test. In addition, we performed histological analysis of the liver and quantified alveolar bone loss by measuring the root surface area on the lower first molar. RESULTS: Oral administration of P. gingivalis induced downregulation of genes that improve insulin sensitivity in adipose tissue (C1qtnf9, Irs1, and Sirt1), but upregulation of genes associated with lipid droplet formation and gluconeogenesis (Plin2, Acox, and G6pc). However, concomitant administration of propolis abrogated these adverse effects of P. gingivalis. Consistent with gene expression, histological analysis showed that administered propolis suppressed hepatic steatosis induced by P. gingivalis. Furthermore, propolis inhibited the elevation of serum endotoxin levels induced by P. gingivalis administration. Contrary to the systemic effects, propolis had no beneficial effect on alveolar bone loss. CONCLUSION: These results suggest that administration of propolis may be effective in suppressing periodontopathic bacteria-induced metabolic changes that increase the risk of various systemic diseases.
Assuntos
Glicemia/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Periodontite/metabolismo , Própole/farmacologia , Substâncias Protetoras/farmacologia , Perda do Osso Alveolar/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Reabsorção Óssea/metabolismo , Brasil , Endotoxemia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Periodontite/microbiologia , Porphyromonas gingivalis/patogenicidade , Própole/química , Substâncias Protetoras/químicaRESUMO
Substantial evidence suggests that periodontal disease increases the risk of developing and progressing extraoral manifestations such as diabetes, atherosclerosis, rheumatoid arthritis, and inflammatory bowel disease. The most probable causative mechanism behind this is the influx of bacteria and/or bacterial products (endotoxin) and inflammatory cytokines into the systemic circulation originating from inflamed periodontal tissues. However, recent studies have revealed that oral bacteria, especially periodontopathic bacteria, play a role in inducing dysbiosis of the gut microbiota resulting induction of gut dysbiosis-related pathology associated with systemic diseases. Conversely, the disruption of gut microbiota has been shown to have a negative impact on the pathogenesis of periodontal disease. Based on our study findings and the available literature, this review presents an overview of the relationship between periodontal disease and systemic health, highlighting the mouth-gut connection.
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Lipopolysaccharide (LPS) from Porphyromonas gingivalis, an oral Gram-negative bacterium, acts as a virulence factor for periodontal disease. Although P. gingivalis LPS does not induce proinflammatory cytokines as strongly as Escherichia coli LPS, it is still able to exploit negative Toll-like receptor (TLR) regulatory pathways and facilitate pathogen persistence. Recent reports suggest that microRNAs (miRNAs) are also involved in the regulation of TLR signaling. Here, we demonstrate that P. gingivalis LPS strongly induces miRNA-146a expression in THP-1 cells and THP-1-derived macrophages. However, the inhibition or overexpression of miR-146a, through the transfection of a specific inhibitor or precursor, respectively, had little effect on cytokine production in macrophages stimulated with P. gingivalis LPS. Moreover, the expression of interleukin-1 associated-kinase-1 (IRAK-1) and tumor-necrosis factor (TNF) receptor-associated factor-6 (TRAF6), potential target molecules of miR-146a, were not affected by the stimulation with P. gingivalis LPS. Because TLR signaling induces various negative regulators, these results call into question the role of miR-146a in cells stimulated with TLR ligands.
Assuntos
Lipopolissacarídeos/imunologia , MicroRNAs/biossíntese , Periodontite/imunologia , Periodontite/microbiologia , Porphyromonas gingivalis/imunologia , Linhagem Celular , Citocinas/biossíntese , Humanos , Quinases Associadas a Receptores de Interleucina-1/biossíntese , Quinases Associadas a Receptores de Interleucina-1/genética , Macrófagos/imunologia , Macrófagos/microbiologia , Fator 6 Associado a Receptor de TNF/biossíntese , Fator 6 Associado a Receptor de TNF/genética , Receptores Toll-Like/metabolismoRESUMO
BACKGROUND: Periodontal disease is suggested to increase the risk of atherothrombotic disease by inducing dyslipidemia. Recently, we demonstrated that proprotein convertase subtilisin/kexin type 9 (PCSK9), which is known to play a critical role in the regulation of circulating low-density lipoprotein (LDL) cholesterol levels, is elevated in periodontitis patients. However, the underlying mechanisms of elevation of PCSK9 in periodontitis patients are largely unknown. Here, we explored whether Porphyromonas gingivalis, a representative periodontopathic bacterium, -induced inflammatory response regulates serum PCSK9 and cholesterol levels using animal models. METHODS: We infected C57BL/6 mice intraperitoneally with Porphyromonas gingivalis, a representative strain of periodontopathic bacteria, and evaluated serum PCSK9 levels and the serum lipid profile. PCSK9 and LDL receptor (LDLR) gene and protein expression, as well as liver X receptors (Lxrs), inducible degrader of the LDLR (Idol), and sterol regulatory element binding transcription factor (Srebf)2 gene expression, were examined in the liver. RESULTS: P. gingivalis infection induced a significant elevation of serum PCSK9 levels and a concomitant elevation of total and LDL cholesterol compared with sham-infected mice. The LDL cholesterol levels were significantly correlated with PCSK9 levels. Expression of the Pcsk9, Ldlr, and Srebf2 genes was upregulated in the livers of the P. gingivalis-infected mice compared with the sham-infected mice. Although Pcsk9 gene expression is known to be positively regulated by sterol regulatory element binding protein (SREBP)2 (human homologue of Srebf2), whereas Srebf2 is negatively regulated by cholesterol, the elevated expression of Srebf2 found in the infected mice is thought to be mediated by P. gingivalis infection. CONCLUSIONS: P. gingivalis infection upregulates PCSK9 production via upregulation of Srebf2, independent of cholesterol levels. Further studies are required to elucidate how infection regulates Srebf2 expression and subsequently influences lipid metabolism.
Assuntos
Infecções por Bacteroidaceae/genética , Infecções por Bacteroidaceae/metabolismo , Porphyromonas gingivalis , Receptores de LDL/genética , Receptores de LDL/metabolismo , Animais , Infecções por Bacteroidaceae/sangue , Colesterol/sangue , LDL-Colesterol/sangue , Modelos Animais de Doenças , Expressão Gênica , Humanos , Lipídeos/sangue , Fígado/metabolismo , Receptores X do Fígado , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores Nucleares Órfãos/genética , Receptores Nucleares Órfãos/metabolismo , Porphyromonas gingivalis/patogenicidade , Pró-Proteína Convertase 9 , Pró-Proteína Convertases/sangue , Pró-Proteína Convertases/genética , Processamento Pós-Transcricional do RNA , Serina Endopeptidases/sangue , Serina Endopeptidases/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Regulação para CimaRESUMO
OBJECTIVE: To evaluate the microbiological and clinical effects of the systemic administration of sitafloxacin (STFX) on periodontal pockets in elderly patients receiving supportive periodontal therapy (SPT). BACKGROUND: Periodontitis is a risk factor for atherosclerosis. Better periodontal health contributes to reduce atherosclerosis-related diseases in elderly population. MATERIALS AND METHODS: Forty-four patients undergoing SPT were randomly assigned to two groups: a test group took 100 mg/day of STFX for five consecutive days, or a control group received scaling and root planing (SRP) under local anaesthesia. Microbiological and clinical parameters were examined at baseline and at 1 and 3 months after therapy. RESULTS: The presence of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia was significantly reduced at 1 month after treatment in both groups. The median reductions of the bacteria between the baseline and 1 month were 3.08 and 2.54% in the STFX- and SRP-treated groups, respectively. Both treatments significantly decreased the probing depth at 1 and 3 months compared to the baseline. CONCLUSION: The systemic administration of STFX is effective at improving periodontal health during SPT and could be an alternative to SRP for elderly patients who cannot undergo anaesthesia or are at risk of tissue injury.
Assuntos
Antibacterianos/uso terapêutico , Periodontite Crônica/microbiologia , Fluoroquinolonas/uso terapêutico , Bolsa Periodontal/microbiologia , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Antibacterianos/administração & dosagem , Anticorpos Antibacterianos/sangue , Carga Bacteriana/efeitos dos fármacos , Bacteroides/efeitos dos fármacos , Periodontite Crônica/terapia , Placa Dentária/microbiologia , Placa Dentária/terapia , Raspagem Dentária , Feminino , Fluoroquinolonas/administração & dosagem , Seguimentos , Hemorragia Gengival/microbiologia , Hemorragia Gengival/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Perda da Inserção Periodontal/microbiologia , Perda da Inserção Periodontal/terapia , Bolsa Periodontal/terapia , Porphyromonas gingivalis/efeitos dos fármacos , Porphyromonas gingivalis/imunologia , Prevotella intermedia/efeitos dos fármacos , Aplainamento Radicular , Treponema denticola/efeitos dos fármacosRESUMO
Background: The effect of oral microbiota on the intestinal microbiota has garnered growing attention as a mechanism linking periodontal diseases to systemic diseases. However, the salivary microbiota is diverse and comprises numerous bacteria with a largely similar composition in healthy individuals and periodontitis patients. Aim: We explored how health-associated and periodontitis-associated salivary microbiota differently colonized the intestine and their subsequent systemic effects. Methods: The salivary microbiota was collected from a healthy individual and a periodontitis patient and gavaged into C57BL/6NJcl[GF] mice. Gut microbial communities, hepatic gene expression profiles, and serum metabolites were analyzed. Results: The gut microbial composition was significantly different between periodontitis-associated microbiota-administered (PAO) and health-associated oral microbiota-administered (HAO) mice. The hepatic gene expression profile demonstrated a distinct pattern between the two groups, with higher expression of lipid and glucose metabolism-related genes. Disease-associated metabolites such as 2-hydroxyisobutyric acid and hydroxybenzoic acid were elevated in PAO mice. These metabolites were significantly correlated with characteristic gut microbial taxa in PAO mice. Conversely, health-associated oral microbiota were associated with higher levels of beneficial serum metabolites in HAO mice. Conclusion: The multi-omics approach used in this study revealed that periodontitis-associated oral microbiota is associated with the induction of disease phenotype when they colonized the gut of germ-free mice.
RESUMO
The role of interleukin (IL)-17 in cellular communication in inflammation has been well described, and a positive correlation between the severity of periodontitis and the level of IL-17 was reported. Although epithelial cells are a major target of IL-17, little is known about the effect of IL-17 on the production of chemokines by human gingival epithelial cells (HGECs). We evaluated the effects of IL-17 on the expression of CXCL8 and CCL2 by HGECs using quantitative real-time PCR and ELISA. In addition, the role of the nuclear factor (NF)-κB signalling pathway in the IL-17-mediated expression of chemokines was assessed using a specific inhibitor. Stimulation with IL-17 up-regulated the expression of CXCL8 mRNA but not of CCL2 mRNA in HGECs, whereas tumour necrosis factor-α (TNF-α) elevated the expression of mRNA for both chemokines. Stimulation with IL-17 up-regulated the secretion of CXCL8 protein, but not the secretion of CCL2 protein. The effect of IL-17 on CXCL8 production was suppressed using an anti-IL-17R Ig, suggesting a role for a specific receptor-ligand interaction. Inhibition of the NF-κB signalling pathway demonstrated that NF-κB activation is required for the CXCL8 expression in HGECs. In conclusion, IL-17 is involved in the regulation of the innate immune response in HGECs by inducing CXCL8 production.
Assuntos
Quimiocina CCL2/efeitos dos fármacos , Gengiva/efeitos dos fármacos , Interleucina-17/farmacologia , Interleucina-8/efeitos dos fármacos , Anticorpos Monoclonais/imunologia , Linhagem Celular , Ensaio de Imunoadsorção Enzimática , Células Epiteliais/efeitos dos fármacos , Gengiva/citologia , Humanos , Imunidade Inata/imunologia , NF-kappa B/antagonistas & inibidores , Subunidade p50 de NF-kappa B/efeitos dos fármacos , Nitrilas/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Interleucina/antagonistas & inibidores , Receptores de Interleucina/imunologia , Receptores de Interleucina-17/antagonistas & inibidores , Receptores de Interleucina-17/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Sulfonas/farmacologia , Fator de Transcrição RelA/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Regulação para CimaRESUMO
Obesity is a risk factor for periodontal disease (PD). Initiation and progression of PD are modulated by complex interactions between oral dysbiosis and host responses. Although obesity is associated with increased susceptibility to bacterial infection, the detailed mechanisms that connect obesity and susceptibility to PD remain elusive. Using fecal microbiota transplantation and a ligature-induced PD model, we demonstrated that gut dysbiosis-associated metabolites from high-fat diet (HFD)-fed mice worsen alveolar bone destruction. Fecal metabolomics revealed elevated purine degradation pathway activity in HFD-fed mice, and recipient mice had elevated levels of serum uric acid upon PD induction. Furthermore, PD induction caused more severe bone destruction in hyperuricemic than normouricemic mice, and the worsened bone destruction was completely abrogated by allopurinol, a xanthine oxidase inhibitor. Thus, obesity increases the risk of PD by increasing production of uric acid mediated by gut dysbiosis. IMPORTANCE Obesity is an epidemic health issue with a rapid increase worldwide. It increases the risk of various diseases, including periodontal disease, an oral chronic infectious disease. Although obesity increases susceptibility to bacterial infection, the precise biological mechanisms that link obesity and susceptibility to periodontal disease remain elusive. Using fecal microbial transplantation, experimental periodontitis, and metabolomics, our study demonstrates uric acid as a causative substance for greater aggravation of alveolar bone destruction in obesity-related periodontal disease. Gut microbiota from obese mice upregulated the purine degradation pathway, and the resulting elevation of serum uric acid promoted alveolar bone destruction. The effect of uric acid was confirmed by administration of allopurinol, an inhibitor of xanthine oxidase. Overall, our study provides new insights into the pathogenic mechanisms of obesity-associated periodontal disease and the development of new therapeutic options for the disease.
Assuntos
Perda do Osso Alveolar/etiologia , Microbioma Gastrointestinal , Obesidade/microbiologia , Periodontite/microbiologia , Ácido Úrico/metabolismo , Perda do Osso Alveolar/patologia , Animais , Dieta Hiperlipídica , Disbiose , Transplante de Microbiota Fecal , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/complicações , Periodontite/etiologia , Fatores de Risco , Ácido Úrico/análiseRESUMO
OBJECTIVE: Rice peptide has antibacterial properties that have been tested in planktonic bacterial culture. However, bacteria form biofilm at disease sites and are resistant to antibacterial agents. The aim of this study was to clarify the mechanisms of action of rice peptide and its amino acid substitution against periodontopathic bacteria and their antibiofilm effects. DESIGN: Porphyromonas gingivalis and Fusobacterium nucleatum were treated with AmyI-1-18 rice peptide or its arginine-substituted analog, G12R, under anaerobic conditions. The amount of biofilm was evaluated by crystal violet staining. The integrity of the bacteria cytoplasmic membrane was studied in a propidium iodide (PI) stain assay and transmission electron microscopy (TEM). RESULTS: Both AmyI-1-18 and G12R inhibited biofilm formation of P. gingivalis and F. nucleatum; in particular, G12R inhibited F. nucleatum at lower concentrations. However, neither peptide eradicated established biofilms significantly. According to the minimum inhibitory concentration and minimum bactericidal concentration against P. gingivalis, AmyI-1-18 has bacteriostatic properties and G12R has bactericidal activity, and both peptides showed bactericidal activity against F. nucleatum. PI staining and TEM analysis indicated that membrane disruption by G12R was enhanced, which suggests that the replacement amino acid reinforced the electostatic interaction between the peptide and bacteria by increase of cationic charge and α-helix content. CONCLUSIONS: Rice peptide inhibited biofilm formation of P. gingivalis and F. nucleatum, and bactericidal activity via membrane destruction was enhanced by amino acid substitution.
Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Fusobacterium nucleatum/efeitos dos fármacos , Oryza/química , Peptídeos/farmacologia , Porphyromonas gingivalis/efeitos dos fármacos , Substituição de Aminoácidos , Fusobacterium nucleatum/crescimento & desenvolvimento , Proteínas de Plantas/farmacologia , Porphyromonas gingivalis/crescimento & desenvolvimentoRESUMO
Background & Aims: Periodontitis increases the risk of nonalcoholic fatty liver disease (NAFLD); however, the underlying mechanisms are unclear. Here, we show that gut dysbiosis induced by oral administration of Porphyromonas gingivalis, a representative periodontopathic bacterium, is involved in the aggravation of NAFLD pathology. Methods: C57BL/6N mice were administered either vehicle, P. gingivalis, or Prevotella intermedia, another periodontopathic bacterium with weaker periodontal pathogenicity, followed by feeding on a choline-deficient, l-amino acid-defined, high-fat diet with 60 kcal% fat and 0.1% methionine (CDAHFD60). The gut microbial communities were analyzed by pyrosequencing the 16S ribosomal RNA genes. Metagenomic analysis was used to determine the relative abundance of the Kyoto Encyclopedia of Genes and Genomes pathways encoded in the gut microbiota. Serum metabolites were analyzed using nuclear magnetic resonance-based metabolomics coupled with multivariate statistical analyses. Hepatic gene expression profiles were analyzed via DNA microarray and quantitative polymerase chain reaction. Results: CDAHFD60 feeding induced hepatic steatosis, and in combination with bacterial administration, it further aggravated NAFLD pathology, thereby increasing fibrosis. Gene expression analysis of liver samples revealed that genes involved in NAFLD pathology were perturbed, and the two bacteria induced distinct expression profiles. This might be due to quantitative and qualitative differences in the influx of bacterial products in the gut because the serum endotoxin levels, compositions of the gut microbiota, and serum metabolite profiles induced by the ingested P. intermedia and P. gingivalis were different. Conclusions: Swallowed periodontopathic bacteria aggravate NAFLD pathology, likely due to dysregulation of gene expression by inducing gut dysbiosis and subsequent influx of gut bacteria and/or bacterial products.
Assuntos
Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica/microbiologia , Porphyromonas gingivalis , Prevotella intermedia , Administração Oral , Animais , Deficiência de Colina , Dieta Hiperlipídica , Fezes/microbiologia , Células Hep G2 , Humanos , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/patologia , RNA Ribossômico 16SRESUMO
Bacterial fimbriae are an important pathogenic factor. It has been demonstrated that fimbrial protein encoded by fimA gene (FimA fimbriae) of Porphyromonas gingivalis not only contributes to the abilities of bacterial adhesion and invasion to host cells, but also strongly stimulates host innate immune responses. However, FimA fimbriae separated from P. gingivalis ATCC 33277 using a gentle procedure showed very weak proinflammatory activity compared with previous reports. Therefore, in the present study, biological characteristics of FimA fimbriae were further analyzed in terms of proinflammatory activity in macrophages. Macrophages differentiated from THP-1 cells were stimulated with native, heat-denatured, or either proteinase- or lipoprotein lipase-treated FimA fimbriae of P. gingivalis ATCC 33277. Stimulating activities of these FimA fimbriae were evaluated by TNF-alpha-inducing activity in the macrophages. To clarify the mode of action of FimA fimbriae, anti-Toll-like receptor (TLR) 2 blocking antibody was added prior to stimulation. Weak stimulatory activity of native FimA fimbriae was enhanced by heat treatment and low-dose proteinase K treatment. Higher dose of proteinase K treatment abrogated this up-regulation. The activity of treated FimA fimbriae was suppressed by anti-TLR2 antibody, and more substantially by lipoprotein lipase treatment. These results suggest that lipoproteins or lipopeptides associated with FimA fimbriae could at least in part account for signaling via TLR2 and subsequent TNF-alpha production in macrophages.
Assuntos
Proteínas de Fímbrias/imunologia , Fímbrias Bacterianas/imunologia , Macrófagos/imunologia , Porphyromonas gingivalis/imunologia , Receptor 2 Toll-Like/biossíntese , Anticorpos Bloqueadores/imunologia , Linhagem Celular , Endopeptidase K/metabolismo , Temperatura Alta , Humanos , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Lipopeptídeos/imunologia , Desnaturação Proteica , Receptor 2 Toll-Like/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossínteseRESUMO
BACKGROUND: Individuals with periodontitis have elevated serum levels of IL-6 and C-reactive protein and have been reported to have a significantly increased risk of developing cardiovascular disease. The transcription factor early growth response factor 1 (Egr-1) has been shown to play an important role in the development and progression of atherosclerosis. However, it is not known whether periodontal infection affects the expression of Egr-1 and subsequent endothelial cells expression of monocyte chemoattractant protein (MCP)-1, a key molecule of leukocyte chemoattraction into vessels. METHODS: Human coronary artery endothelial cells (HCAECs) were stimulated with either sonicated extracts from Porphyromonas gingivalis strains 381 or SU63, or a combination of IL-6 and soluble IL-6 receptor (IL-6/sIL-6R). The expression of Egr-1, and subsequently MCP-1, was then analyzed. The role of Egr-1 on MCP-1 expression was analyzed by siRNA transfection. RESULTS: Both P. gingivalis antigens and IL-6/sIL-6R stimulations upregulated the expression of Egr-1, with a more robust effect by IL-6/sIL-6R. Increased expression of Egr-1 coincided with MCP-1 production, and Egr-1 downregulation by siRNA suppressed this effect. CONCLUSION: These results clearly suggest that periodontal infection has the potential to affect HCAECs and hence contribute to the development of subsequent atherosclerosis.
Assuntos
Antígenos de Bactérias/imunologia , Quimiocina CCL2/metabolismo , Vasos Coronários/imunologia , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Células Endoteliais/imunologia , Interleucina-6/metabolismo , Porphyromonas gingivalis/imunologia , Células Cultivadas , Quimiocina CCL2/genética , Vasos Coronários/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/genética , Células Endoteliais/metabolismo , Humanos , Interferência de RNA , RNA Mensageiro/metabolismo , Receptores de Interleucina-6/metabolismo , Proteínas Recombinantes/metabolismo , Regulação para CimaRESUMO
The aim of this study was to examine the effect of adjunct local minocycline administration on the microbiological parameters of subgingival plaque samples in the residual periodontal pockets. Ten chronic periodontitis patients under a supportive periodontal therapy regimen were recruited. After subgingival debridement, either 2% minocycline gel, Periocline™, (Test Group) or a placebo (Control Group) was administered to the selected sites once a week for three weeks. Subgingival plaque was collected at baseline, and at four weeks and eight weeks. The microbiological composition was analyzed by 16S ribosomal RNA sequencing. In the Test Group, α-diversity (evenness) decreased compared to the baseline (p = 0.005) and was lower compared to the control group at four weeks (p = 0.003). The microbial community composition between the two groups was significantly different at four weeks (p = 0.029). These changes were attributable to a decrease in the bacteria associated with periodontitis and an increase in the bacteria associated with periodontal health. Additionally, the improvement in bleeding on probing continued at eight weeks; however, there were little microbial effects of 2% minocycline gel observed at eight weeks. The control group demonstrated no change throughout the eight-week experimental period. Thus, local minocycline administration can change the subgingival microbial community of residual periodontal pockets.