RESUMO
OBJECTIVE: The rice rat (Oryzomys palustris) develops periodontitis-like lesions when fed a diet rich in sucrose and casein (H-SC). We aimed to establish whether this model can accurately mimic the development of human periodontitis. MATERIALS AND METHODS: For this purpose, 28-day-old rice rats (15/group) were assigned to standard (STD) or H-SC diets and sacrificed after 6, 12, and 18 weeks. Jaws were processed for morphometric, histometric, histologic, histomorphometric, and micro-CT analyses. RESULTS: We found a progressive increase in horizontal alveolar bone loss (ABL) with age in maxillae of rats fed the STD diet as determined by morphometry. The H-SC diet exacerbated horizontal ABL at the palatal surface at 12 and 18 weeks. Furthermore, increased vertical ABL was detected in mandibles and maxillae of rats fed the H-SC diet for 12 and/or 18 weeks by histometry and micro-CT. Remarkably, the H-SC diet significantly increased bone remodeling at the interproximal alveolar bone of mandibles from rats fed for 6 weeks, but not in those fed for longer periods. CONCLUSIONS: These findings indicate that the H-SC diet induced a transient increase in alveolar bone remodeling, which is followed by ABL characteristic of moderate periodontitis.
Assuntos
Perda do Osso Alveolar/etiologia , Modelos Animais de Doenças , Periodontite/etiologia , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/patologia , Ração Animal/efeitos adversos , Animais , Caseínas/efeitos adversos , Sacarose Alimentar/efeitos adversos , Feminino , Masculino , Sigmodontinae , Microtomografia por Raio-XRESUMO
Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia are periodontal pathogens associated with the etiology of adult periodontitis as polymicrobial infections. Recent studies demonstrated that oral infection with P. gingivalis induces both periodontal disease and atherosclerosis in hyperlipidemic and proatherogenic ApoE(-/-) mice. In this study, we explored the expression of microRNAs (miRNAs) in maxillas (periodontium) and spleens isolated from ApoE(-/-) mice infected with P. gingivalis, T. denticola, and T. forsythia as a polymicrobial infection. miRNA expression levels, including miRNA miR-146a, and associated mRNA expression levels of the inflammatory cytokines tumor necrosis factor alpha (TNF-α) and interleukin-1ß (IL-1ß) were measured in the maxillas and spleens from mice infected with periodontal pathogens and compared to those in the maxillas and spleens from sham-infected controls. Furthermore, in response to these periodontal pathogens (as mono- and polymicrobial heat-killed and live bacteria), human THP-1 monocytes demonstrated similar miRNA expression patterns, including that of miR-146a, in vitro. Strikingly, miR-146a had a negative correlation with TNF-α secretion in vitro, reducing levels of the adaptor kinases IL-1 receptor-associated kinase 1 (IRAK-1) and TNF receptor-associated factor 6 (TRAF6). Thus, our studies revealed a persistent association of miR-146a expression with these periodontal pathogens, suggesting that miR-146a may directly or indirectly modulate or alter the chronic periodontal pathology induced by these microorganisms.
Assuntos
Infecções por Bactérias Gram-Negativas/genética , Infecções por Bactérias Gram-Negativas/microbiologia , MicroRNAs/biossíntese , Periodontite/genética , Periodontite/microbiologia , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/imunologia , Bacteroides/imunologia , Western Blotting , Modelos Animais de Doenças , Infecções por Bactérias Gram-Negativas/imunologia , Humanos , Interleucina-1beta/biossíntese , Interleucina-1beta/imunologia , Masculino , Camundongos , Camundongos Knockout , MicroRNAs/genética , MicroRNAs/imunologia , Monócitos/imunologia , Monócitos/metabolismo , Periodontite/imunologia , Porphyromonas gingivalis/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Baço/imunologia , Baço/metabolismo , Treponema denticola/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/imunologiaRESUMO
This study tested the hypothesis that pregnant female baboons exhibit increased levels of various inflammatory mediators in serum resulting from ligature-induced periodontitis, and that these profiles would relate to periodontal disease severity/extent in the animals. The animals were sampled at baseline (B), mid-pregnancy (MP; two quadrants ligated) and at delivery (D; four quadrants ligated). All baboons developed increased plaque, gingival inflammation and bleeding, pocket depths and attachment loss following placement of the ligatures. By MP, both prostaglandin E(2) (PGE(2)) and bactericidal permeability inducing factor (BPI) were greater than baseline, while increased levels of interleukin (IL)-6 occurred in the experimental animals by the time of delivery. IL-8, MCP-1 and LBP all decreased from baseline through the ligation phase of the study. Stratification of the animals by baseline clinical presentation demonstrated that PGE(2), LBP, IL-8 and MCP-1 levels were altered throughout the ligation interval, irrespective of baseline clinical values. IL-6, IL-8 and LBP were significantly lower in the subset of animals that demonstrated the least clinical response to ligation, indicative of progressing periodontal disease. PGE(2), macrophage chemotactic protein (MCP)-1, regulated upon activation, normal T cell expressed and secreted (RANTES) and LBP were decreased in the most diseased subset of animals at delivery. Systemic antibody responses to Fusobacterium nucleatum, Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans and Campylobacter rectus were associated most frequently with variations in inflammatory mediator levels. These results provide a profile of systemic inflammatory mediators during ligature-induced periodontitis in pregnant baboons. The relationship of the oral clinical parameters to systemic inflammatory responses is consistent with a contribution to adverse pregnancy outcomes in a subset of the animals.
Assuntos
Mediadores da Inflamação/sangue , Periodontite/imunologia , Complicações na Gravidez/imunologia , Proteínas de Fase Aguda , Animais , Anticorpos Antibacterianos/sangue , Peptídeos Catiônicos Antimicrobianos/sangue , Proteínas Sanguíneas , Proteínas de Transporte/sangue , Citocinas/sangue , Dinoprostona/sangue , Modelos Animais de Doenças , Progressão da Doença , Feminino , Gengivite , Imunoglobulina G/sangue , Ligadura/efeitos adversos , Glicoproteínas de Membrana/sangue , Papio , Índice Periodontal , Periodontite/sangue , Periodontite/etiologia , Periodontite/fisiopatologia , Gravidez , Complicações na Gravidez/sangue , Complicações na Gravidez/etiologia , Complicações na Gravidez/fisiopatologiaRESUMO
OBJECTIVE: This study was designed to test the hypothesis that periodontal pathogens Tannerella forsythia and Porphyromonas gingivalis are synergistic in terms of virulence potential using a model of mixed-microbial infection in rats. MATERIALS AND METHODS: Three groups of rats were infected orally with either T. forsythia or P. gingivalis in mono-bacterial infections or as mixed-microbial infections for 12 weeks and a sham-infected group were used as a control. This study examined bacterial infection, inflammation, immunity, and alveolar bone loss changes with disease progression. RESULTS: Tannerella forsythia and P. gingivalis genomic DNA was detected in microbial samples from infected rats by PCR indicating their colonization in the rat oral cavity. Primary infection induced significantly high IgG, IgG2b, IgG1, and IgG2a antibody levels indicating activation of mixed Th1 and Th2 immune responses. Rats infected with the mixed-microbial consortium exhibited significantly increased palatal horizontal and interproximal alveolar bone loss. Histological examinations indicated significant hyperplasia of the gingival epithelium with moderate inflammatory infiltration and apical migration of junctional epithelium. The results observed differ compared to uninfected controls. CONCLUSION: Our results indicated that T. forsythia and P. gingivalis exhibit virulence, but not virulence synergy, resulting in the immuno-inflammatory responses and lack of humoral immune protection during periodontitis in rats.
Assuntos
Bacteroides/patogenicidade , Imunidade Humoral/imunologia , Periodontite/microbiologia , Porphyromonas gingivalis/patogenicidade , Perda do Osso Alveolar/imunologia , Perda do Osso Alveolar/microbiologia , Perda do Osso Alveolar/patologia , Animais , Anticorpos Antibacterianos/análise , Antígenos de Bactérias/análise , Proteínas de Bactérias/análise , Infecções por Bacteroidaceae/imunologia , Bacteroides/imunologia , Infecções por Bacteroides/imunologia , Modelos Animais de Doenças , Progressão da Doença , Inserção Epitelial/imunologia , Inserção Epitelial/microbiologia , Epitélio/imunologia , Epitélio/microbiologia , Feminino , Hiperplasia Gengival/imunologia , Hiperplasia Gengival/microbiologia , Imunoglobulina G/análise , Proteínas de Membrana/análise , Periodontite/imunologia , Periodontite/patologia , Porphyromonas gingivalis/imunologia , Distribuição Aleatória , Ratos , Células Th1/imunologia , Células Th2/imunologia , Fatores de Tempo , VirulênciaRESUMO
UNLABELLED: Periodontal inflammation with alveolar bone resorption is a hallmark of periodontitis. We hypothesized that extracorporeal shock wave therapy (ESWT) could promote the regeneration of alveolar bone following Porphyromonas gingivalis-induced periodontitis in rats. Rats were infected with P. gingivalis for 10 wks, which caused alveolar bone resorption. The rats were then treated with a single episode of 100, 300, or 1000 impulses of shock wave on both cheeks at energy levels 0.1 mJ/mm(2). Alveolar bone levels were determined at 0, 3, 6, and 12 wks following ESWT and compared with those in untreated controls. Infected rats treated with 300 and 1000 impulses demonstrated significantly improved alveolar bone levels at 3 wks compared with untreated controls, and the improved levels remained for at least 6 wks in most rats. The results demonstrated effective regeneration of alveolar bone by ESWT and suggested that ESWT should be evaluated as an adjunct in the regeneration of periodontal tissues following periodontal disease. ABBREVIATIONS: ESWT, extracorporeal shock wave therapy; PCR, polymerase chain-reaction.
Assuntos
Perda do Osso Alveolar/radioterapia , Regeneração Óssea/efeitos da radiação , Reabsorção Óssea/radioterapia , Ondas de Choque de Alta Energia/uso terapêutico , Perda do Osso Alveolar/etiologia , Perda do Osso Alveolar/microbiologia , Animais , Infecções por Bacteroidaceae/complicações , Reabsorção Óssea/etiologia , Reabsorção Óssea/microbiologia , Modelos Animais de Doenças , Feminino , Gengivite/complicações , Gengivite/microbiologia , Porphyromonas gingivalis , Ratos , Ratos Sprague-DawleyRESUMO
Toll-like-receptors (TLRs) play a significant role in the generation of a specific innate immune response against invading pathogens. TLR2 and TLR4 signaling contributes to infection-induced inflammation in periodontal disease (PD) and atherosclerosis. Observational studies point towards a relationship between PD and atherosclerosis, but the role of TLR2 and TLR4 in the recognition of multiple oral pathogens and their modulation of host response leading to atherosclerosis are not clear. We evaluated the role of TLR2 and TLR4 signaling in the induction of both PD and atherosclerosis in TLR2-/- and TLR4-/- mice to polymicrobial infection with periodontal pathogens Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Fusobacterium nucleatum. Polybacterial infections have established gingival colonization in TLR2-/- and TLR4-/- mice and induction of a pathogen-specific immunoglobulin G immune response. But TLR deficiency dampened accelerated alveolar bone resorption and intrabony defects, indicating a central role in infection-induced PD. Periodontal bacteria disseminated from gingival tissue to the heart and aorta through intravascular dissemination; however, there was no increase in atherosclerosis progression in the aortic arch. Polybacterial infection does not alter levels of serum risk factors such as oxidized low-density lipoprotein, nitric oxide, and lipid fractions in both mice. Polymicrobial-infected TLR2-/- mice demonstrated significant levels (P < 0.05 to P < 0.01) of T helper type 2 [transforming growth factor-ß1 , macrophage inflammatory protein-3α, interleukin-13 (IL-13)] and T helper type 17 (IL-17, IL-21, IL-22, IL-23) splenic T-cell cytokine responses. Increased heat-shock protein expression, hspa1a for Hsp 70, was observed for both TLR2-/- and TLR4-/- mice. This study supports a role for TLR2 and TLR4 in PD and atherosclerosis, corroborating an intricate association between two inflammatory diseases.
Assuntos
Aterosclerose/fisiopatologia , Reabsorção Óssea/fisiopatologia , Coinfecção/imunologia , Inflamação/fisiopatologia , Receptor 2 Toll-Like/deficiência , Receptor 4 Toll-Like/deficiência , Animais , Aterosclerose/etiologia , Aterosclerose/imunologia , Reabsorção Óssea/etiologia , Reabsorção Óssea/imunologia , Coinfecção/microbiologia , Citocinas/sangue , Fusobacterium nucleatum/imunologia , Proteínas de Choque Térmico/sangue , Inflamação/etiologia , Inflamação/imunologia , Lipoproteínas LDL/sangue , Camundongos , Óxido Nítrico/sangue , Doenças Periodontais/microbiologia , Porphyromonas gingivalis/imunologia , Tannerella forsythia/imunologia , Células Th2/imunologia , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/imunologia , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/imunologia , Treponema denticola/imunologiaRESUMO
OBJECTIVE: To characterize in rice rats: (a) periodontitis (PD) progress with feeding of standard laboratory rat chow (STD) during ages 4-80 weeks; and (b) PD progress with feeding of a high sucrose-casein (H-SC) diet during young adulthood. METHODS: One group (N=12) was euthanized at age 4 weeks (Baseline). Four groups (N=8-16) consumed a STD diet from baseline and were necropsied at ages 22, 30, 52, and 80 weeks. Three groups (N=10-16) consumed an H-SC diet from baseline. Two were necropsied at ages 22 and 30 weeks, respectively. The third switched to the STD diet at age 22 weeks and was necropsied at age 30 weeks. All mandibles/maxillae were assessed by histometry for degree of periodontal inflammation (PD Score), alveolar crest height (ACH, mm), and horizontal alveolar bone height (hABH, mm2). RESULTS: In STD diet rats aged ≥30 weeks, all endpoints were worse (P<0.05) than at Baseline. In H-SC diet rats aged ≥22 weeks, all endpoints were worse than at Baseline (P<0.05). At age 22 weeks, all endpoints were worse in the H-SC group than in the STD group (P<0.05). By age 30 weeks, the STD and H-SC groups did not differ. CONCLUSIONS: 1) STD diet fed rice rats develop moderate/severe PD by age 30 weeks; 2) an H-SC diet accelerates moderate/severe PD development; and 3) switching to a STD diet does not halt/reverse PD that was accelerated by an H-SC diet. These data further clarify use of the rice rat as a PD model.
Assuntos
Perda do Osso Alveolar/etiologia , Perda do Osso Alveolar/patologia , Dieta , Modelos Animais de Doenças , Osteoporose/etiologia , Osteoporose/patologia , Periodontite/etiologia , Periodontite/patologia , Perda do Osso Alveolar/sangue , Processo Alveolar/anatomia & histologia , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/patologia , Ração Animal , Animais , Glicemia/metabolismo , Peso Corporal , Colesterol/sangue , Sacarose Alimentar/administração & dosagem , Sacarose Alimentar/efeitos adversos , Insulina/sangue , Masculino , Osteoporose/sangue , Periodontite/sangue , Distribuição Aleatória , Ratos , SigmodontinaeRESUMO
Gingival inflammation and alveolar bone resorption are hallmarks of adult periodontitis, elicited in response to oral micro-organisms such as Porphyromonas gingivalis. We hypothesized that omega (omega)-3 fatty acids (FA) dietary supplementation would modulate inflammatory reactions leading to periodontal disease in infected rats. Rats were fed fish oil (omega-3 FA) or corn oil (n-6 FA) diets for 22 weeks and were infected with P. gingivalis. Rats on the omega-3 FA diet exhibited elevated serum levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), documenting diet-induced changes. PCR analyses demonstrated that rats were orally colonized by P. gingivalis; increased IgG antibody levels substantiated this infection. P. gingivalis-infected rats treated with omega-3 FA had significantly less alveolar bone resorption. These results demonstrated the effectiveness of an omega-3 FA-supplemented diet in modulating alveolar bone resorption following P. gingivalis infection, and supported that omega-3 FA may be a useful adjunct in the treatment of periodontal disease.
Assuntos
Perda do Osso Alveolar/prevenção & controle , Ácidos Graxos Ômega-3/uso terapêutico , Óleos de Peixe/uso terapêutico , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/microbiologia , Análise de Variância , Animais , Infecções por Bacteroidaceae/prevenção & controle , Suplementos Nutricionais , Ácidos Graxos/sangue , Feminino , Porphyromonas gingivalis/isolamento & purificação , Radiografia , Ratos , Ratos Sprague-DawleyRESUMO
UNLABELLED: Enoxacin inhibits binding between the B-subunit of vacuolar H(+)-ATPase (V-ATPase) and microfilaments, and also between osteoclast formation and bone resorption in vitro. We hypothesized that a bisphosphonate derivative of enoxacin, bis-enoxacin (BE), which was previously studied as a bone-directed antibiotic, might have similar activities. BE shared a number of characteristics with enoxacin: It blocked binding between the recombinant B-subunit and microfilaments and inhibited osteoclastogenesis in cell culture with IC50s of about 10 µM in each case. BE did not alter the relative expression levels of various osteoclast-specific proteins. Even though tartrate-resistant acid phosphatase 5b was expressed, proteolytic activation of the latent pro-enzyme was inhibited. However, unlike enoxacin, BE stimulated caspase-3 activity. BE bound to bone slices and inhibited bone resorption by osteoclasts on BE-coated bone slices in cell culture. BE reduced the amount of orthodontic tooth movement achieved in rats after 28 days. Analysis of these data suggests that BE is a novel anti-resorptive molecule that is active both in vitro and in vivo and may have clinical uses. ABBREVIATIONS: BE, bis-enoxacin; V-ATPase, vacuolar H(+)-ATPase; TRAP, tartrate-resistant acid phosphatase; αMEM D10, minimal essential media, alpha modification with 10% fetal bovine serum; SDS-PAGE, sodium dodecyl sulfate-polyacrylamide gel electrophoresis; RANKL, receptor activator of nuclear factor kappa B-ligand; NFATc1, nuclear factor of activated T-cells; ADAM, a disintegrin and metalloprotease domain; OTM, orthodontic tooth movement.
Assuntos
Perda do Osso Alveolar/prevenção & controle , Enoxacino/farmacologia , Inibidores da Síntese de Ácido Nucleico/farmacologia , Osteoclastos/efeitos dos fármacos , Técnicas de Movimentação Dentária , Citoesqueleto de Actina/metabolismo , Animais , Apoptose , Caspase 3/metabolismo , Bovinos , Células Cultivadas , Difosfonatos/farmacologia , Masculino , Ligação Proteica/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , ATPases Vacuolares Próton-Translocadoras/antagonistas & inibidoresRESUMO
Streptococcus mutans, a dental caries pathogen, also causes endocarditis and is detected in atheroscelerotic plaque. We investigated the potential for an invasive strain of S. mutans, OMZ175, to accelerate plaque growth in apolipoprotein E deficient (ApoE(null)) mice without and with balloon angioplasty (BA) injury, a model of restenosis. ApoE(null) mice were divided into 4 groups (N = 10), 2 with and 2 without BA. One each of the BA and non-BA groups was infected with S. mutans (Sm). S. mutans DNA, plaque area, inflammatory cell invasion, and Toll-like receptor (TLR) expression were measured at 6-20 weeks post-infection. S. mutans genomic DNA was detected in the aorta, liver, spleen, and heart. Plaque growth was significantly increased in infected mice with BA (Sm+BA) vs. those in the non-infected groups (p < 0.03). Plaque size was increased after infection without BA (Sm), but did not reach significance. Aortic specimens from both S. mutans and Sm+BA groups displayed increased numbers of macrophages, and TLR4 expression was increased in BA mice. In conclusion, S. mutans infection accelerated plaque growth, macrophage invasion, and TLR4 expression after angioplasty. S. mutans may also be associated with atherosclerotic plaque growth in non-injured arteries.
Assuntos
Apolipoproteínas E/deficiência , Aterosclerose/microbiologia , Infecções Estreptocócicas/complicações , Streptococcus mutans , Receptor 4 Toll-Like/biossíntese , Angioplastia com Balão/efeitos adversos , Animais , Aorta/microbiologia , Apolipoproteínas E/genética , Aterosclerose/etiologia , Aterosclerose/metabolismo , DNA Bacteriano/análise , Placa Dentária/complicações , Placa Dentária/metabolismo , Placa Dentária/microbiologia , Coração/microbiologia , Ativação de Macrófagos , Camundongos , Camundongos Knockout , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/metabolismoRESUMO
Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia are consistently associated with adult periodontitis. This study sought to document the host transcriptome to a P. gingivalis, T. denticola, and T.forsythia challenge as a polymicrobial infection using a murine calvarial model of acute inflammation and bone resorption. Mice were infected with P. gingivalis, T. denticola, and T. forsythia over the calvaria, after which the soft tissues and calvarial bones were excised. A Murine GeneChip(®) array analysis of transcript profiles showed that 6997 genes were differentially expressed in calvarial bones (P < 0.05) and 1544 genes were differentially transcribed in the inflamed tissues after the polymicrobial infection. Of these genes, 4476 and 1035 genes in the infected bone and tissues were differentially expressed by upregulation. Biological pathways significantly impacted by the polymicrobial infection in calvarial bone included leukocyte transendothelial migration (LTM), cell adhesion molecules, adherens junction, major histocompatibility complex antigen, extracellular matrix-receptor interaction, and antigen processing and presentation resulting in inflammatory/cytokine/chemokine transcripts stimulation in bone and soft tissue. Intense inflammation and increased activated osteoclasts were observed in calvarias compared with sham-infected controls. Quantitative real-time RT-PCR analysis confirmed that the mRNA level of selected genes corresponded with the microarray expression. The polymicrobial infection regulated several LTM and extracellular membrane pathway genes in a manner distinct from mono-infection with P. gingivalis, T. denticola, or T. forsythia. To our knowledge, this is the first definition of the polymicrobially induced transcriptome in calvarial bone and soft tissue in response to periodontal pathogens.
Assuntos
Perda do Osso Alveolar/microbiologia , Bacteroides/genética , Periodontite Crônica/microbiologia , Coinfecção/microbiologia , Mucosa Bucal/microbiologia , Porphyromonas gingivalis/genética , Transcriptoma/genética , Treponema denticola/genética , Junções Aderentes , Perda do Osso Alveolar/genética , Animais , Moléculas de Adesão Celular/genética , Fenômenos Fisiológicos Celulares/genética , Quimiotaxia de Leucócito/genética , Colágeno Tipo III/genética , Proteínas da Matriz Extracelular/genética , Feminino , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Camundongos , Camundongos Endogâmicos BALB C , Análise em Microsséries , Reação em Cadeia da Polimerase em Tempo Real , Crânio/microbiologia , Migração Transendotelial e Transepitelial/genéticaRESUMO
Tannerella forsythia is associated with subgingival biofilms in adult periodontitis, although the molecular mechanisms contributing to chronic inflammation and loss of periodontal bone remain unclear. We examined changes in the host transcriptional profiles during a T. forsythia infection using a murine calvarial model of inflammation and bone resorption. Tannerella forsythia was injected into the subcutaneous soft tissue over calvariae of BALB/c mice for 3 days, after which the soft tissues and calvarial bones were excised. RNA was isolated and Murine GeneChip (Affymetrix, Santa Clara, CA) array analysis of transcript profiles showed that 3226 genes were differentially expressed in the infected soft tissues (P < 0.05) and 2586 genes were differentially transcribed in calvarial bones after infection. Quantitative real-time reverse transcription-polymerase chain reaction analysis of transcription levels of selected genes corresponded well with the microarray results. Biological pathways significantly impacted by T. forsythia infection in calvarial bone and soft tissue included leukocyte transendothelial migration, cell adhesion molecules (immune system), extracellular matrix-receptor interaction, adherens junction, and antigen processing and presentation. Histologic examination revealed intense inflammation and increased osteoclasts in calvariae compared with controls. In conclusion, localized T. forsythia infection differentially induces transcription of a broad array of host genes, and the profiles differ between inflamed soft tissues and calvarial bone.
Assuntos
Perda do Osso Alveolar/genética , Perda do Osso Alveolar/microbiologia , Infecções por Bacteroides/genética , Periodontite Crônica/genética , Periodontite Crônica/microbiologia , Animais , Moléculas de Adesão Celular/genética , Feminino , Perfilação da Expressão Gênica , Leucócitos/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Análise de Sequência com Séries de Oligonucleotídeos , Receptores de Superfície Celular/genética , Crânio , Transcrição Gênica , Migração Transendotelial e Transepitelial/genéticaRESUMO
Treponema denticola is associated with subgingival biofilms in adult periodontitis and with acute necrotizing ulcerative gingivitis. However, the molecular mechanisms by which T. denticola impacts periodontal inflammation and alveolar bone resorption remain unclear. Here, we examined changes in the host transcriptional profiles during a T. denticola infection using a murine calvarial model of inflammation and bone resorption. T. denticola was injected into the subcutaneous soft tissue over the calvaria of BALB/c mice for 3 days, after which the soft tissues and the calvarial bones were excised. RNA was isolated and analysed for transcript profiling using Murine GeneChip arrays. Following T. denticola infection, 2905 and 1234 genes in the infected calvarial bones and soft tissues, respectively, were differentially expressed (P Assuntos
Reabsorção Óssea/genética
, Reabsorção Óssea/microbiologia
, Citocinas/biossíntese
, Mediadores da Inflamação/metabolismo
, Treponema denticola/fisiologia
, Infecções por Treponema/genética
, Animais
, Anticorpos Antibacterianos/sangue
, Reabsorção Óssea/imunologia
, Citocinas/genética
, Células Epiteliais/microbiologia
, Feminino
, Perfilação da Expressão Gênica
, Interações Hospedeiro-Patógeno
, Camundongos
, Camundongos Endogâmicos BALB C
, Análise de Sequência com Séries de Oligonucleotídeos
, Osteócitos/microbiologia
, Reação em Cadeia da Polimerase Via Transcriptase Reversa
, Crânio
, Ativação Transcricional
, Infecções por Treponema/imunologia
RESUMO
Porphyromonas gingivalis has been associated with subgingival biofilms in adult periodontitis. However, the molecular mechanisms of its contribution to chronic gingival inflammation and loss of periodontal structural integrity remain unclear. This investigation aimed to examine changes in the host transcriptional profiles during a P. gingivalis infection using a murine calvarial model of inflammation and bone resorption. P. gingivalis FDC 381 was injected into the subcutaneous soft tissue over the calvaria of BALB/c mice for 3 days, after which the soft tissues and calvarial bones were excised. RNA was isolated from infected soft tissues and calvarial bones and was analysed for transcript profiles using Murine GeneChip((R)) arrays to provide a molecular profile of the events that occur following infection of these tissues. After P. gingivalis infection, 6452 and 2341 probe sets in the infected soft tissues and calvarial bone, respectively, were differentially expressed (P = 0.05). Biological pathways significantly impacted by P. gingivalis infection in tissues and calvarial bone included cell adhesion (immune system) molecules, Toll-like receptors, B-cell receptor signaling, transforming growth factor-beta cytokine family receptor signaling, and major histocompatibility complex class II antigen processing pathways resulting in proinflammatory, chemotactic effects, T-cell stimulation, and downregulation of antiviral and T-cell chemotactic effects. P. gingivalis-induced inflammation activated osteoclasts, leading to local bone resorption. This is the first in vivo evidence that localized P. gingivalis infection differentially induces transcription of a broad array of host genes, the profiles of which differed between inflamed soft tissues and calvarial bone.
Assuntos
Infecções por Bacteroidaceae/genética , Reabsorção Óssea/genética , Reabsorção Óssea/microbiologia , Mediadores da Inflamação/metabolismo , Inflamação/genética , Porphyromonas gingivalis/fisiologia , Animais , Osso e Ossos/microbiologia , Moléculas de Adesão Celular/genética , Citocinas/genética , Feminino , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno , Camundongos , Camundongos Endogâmicos BALB C , Análise de Sequência com Séries de Oligonucleotídeos , Osteoclastos/fisiologia , Receptores Toll-Like/genética , Transcrição GênicaRESUMO
INTRODUCTION: Porphyromonas gingivalis is strongly implicated in the etiology of adult periodontitis by inducing inflammatory cytokines, resulting in gingival and periodontal tissue inflammation and alveolar bone resorption. This study tested the hypothesis that supplementing the diet with omega-3 fatty acid (omega-3 FA; i.e. fish oil) would exert anti-inflammatory effects in the gingival tissues of P. gingivalis-infected rats. METHODS: Rats were fed either fish oil or corn oil diets ad libitum for 22 weeks and infected with P. gingivalis strain 381 or strain A7A1-28. After sacrifice, rat gingival tissues were excised and the RNA was isolated and analyzed for proinflammatory mediators [interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), IL-6], T helper type 1 and type 2 cytokines [interferon-gamma (IFN-gamma), IL-4, IL-10), antioxidant enzymes [catalase (CAT), superoxide dismutase (SOD)], and genes critical for eicosanoid mediator production [cyclo-oxygenase-2 (COX-2), 5-lipoxygenase (5-LO)] by reverse transcription-polymerase chain reaction using rat-specific primers. RESULTS: Rats on the omega-3 FA diet exhibited decreased proinflammatory cytokine gene expression (IL-1beta, TNF-alpha) and enhanced IFN-gamma, CAT and SOD messenger RNA expression compared to rats fed a corn oil diet, supporting a diet-induced modulation of host inflammatory reactions. Analyses of alveolar bone resorption in the rats related to gene expression profiles demonstrated significant positive correlations with IL-1beta, IL-6 and COX-2 and negative correlations with CAT and SOD. CONCLUSION: These findings suggest that diets enriched for omega-3 FA modulate the local gingival inflammatory milieu of the host following oral P. gingivalis infection, which impacts on alveolar bone resorption in rats.
Assuntos
Citocinas/biossíntese , Ácidos Graxos Ômega-3/fisiologia , Mediadores da Inflamação/metabolismo , Periodontite/metabolismo , Perda do Osso Alveolar/metabolismo , Perda do Osso Alveolar/microbiologia , Perda do Osso Alveolar/prevenção & controle , Animais , Infecções por Bacteroidaceae/metabolismo , Infecções por Bacteroidaceae/prevenção & controle , Ciclo-Oxigenase 2/biossíntese , Suplementos Nutricionais , Ácidos Graxos Ômega-3/uso terapêutico , Feminino , Óleos de Peixe/uso terapêutico , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Interleucina-1beta/biossíntese , Interleucina-6/biossíntese , Periodontite/microbiologia , Periodontite/prevenção & controle , Porphyromonas gingivalis/fisiologia , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/biossínteseRESUMO
Indirect hemagglutination and 51Cr release tests (IHAT and 51-CRT respectively) were compared in patients with recurrent herpes simplex virus (HSV) infections from whom HSV-1 or HSV-2 was isolated. Both tests were equally sensitive and specific in detecting HSV antibodies. However, IHAT was more specific in detecting homologous HSV antibody response in patients with recurrent HSV-2 infections. Past infections with HSV-1 in the patients with dual infections were detected by determining HSV-type specific antibodies by inhibition of IHAT. Cross absorption studies showed that the antibody reactivity measured by the two tests was qualitatively and quantitatively different. Nevertheless, IHAT has been found to be more appropriate test for seroepidemiologic studies of HSV-2 infections because of its specificity, rapidity and less cost, whereas, 51-CRT appears to measure antibodies against recent and more predominant type of infecting HSV.
Assuntos
Anticorpos Antivirais/análise , Radioisótopos de Cromo , Testes de Hemaglutinação , Herpes Simples/diagnóstico , Simplexvirus/imunologia , Herpes Simples/imunologia , Humanos , MasculinoRESUMO
Porphyromonas gingivalis appears to be a major contributor to periodontal disease, especially soft tissue destruction, which is reflected by the ability to cause invasive, spreading lesions, and tissue inflammation in a murine abscess model. This study investigated the role of hemin on the regulation of growth and virulence of P. gingivalis strains. P. gingivalis strains W50, A7A1-28, 3079, 381, W50/BEI, and NG4B19 were grown in broth and on blood agar plates. P. gingivalis cells grown under iron-depleted conditions for multiple passages showed significantly decreased lesion size in mice, in contrast to cells grown under iron-normal (5 microg/ml) and iron-elevated conditions. Statistically significant (P < 0.01) decreases in gingipain enzyme activity were found among the strains grown under iron-depleted conditions. P. gingivalis grown in the presence of blood induced significantly different lesion type, lesion size, lesion onset, and mortality. Elevated hemin resulted in increased cell-associated iron in P. gingivalis, which increased the capacity of the microorganism to survive at times of iron deprivation. These results indicate that hemin or iron availability regulates multiple aspects related to P. gingivalis virulence, including growth, survival, gingipain levels, and iron accumulation.
Assuntos
Hemina/metabolismo , Ferro/metabolismo , Porphyromonas gingivalis/crescimento & desenvolvimento , Porphyromonas gingivalis/patogenicidade , Abscesso/microbiologia , Adesinas Bacterianas , Animais , Cisteína Endopeptidases/metabolismo , Meio Ambiente , Cisteína Endopeptidases Gingipaínas , Hemaglutininas/metabolismo , Hemina/farmacologia , Hemina/fisiologia , Deficiências de Ferro , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Modelos Animais , Porphyromonas gingivalis/metabolismo , Coelhos , Estatísticas não Paramétricas , Virulência/efeitos dos fármacos , Virulência/fisiologiaRESUMO
Periodontitis is a chronic inflammatory disease initiated by a multitude of bacteria. Persistent infection leads to generation of various inflammatory mediators, resulting in tissue destruction and osteoclastic resorption of the alveolar bone. This study describes a novel in vivo murine calvarial model to assess the effects of oral pathogens on the expression of three proinflammatory cytokines [interleukin (IL)-1beta, IL-6, and tumor necrosis factor (TNF)-alpha] which are involved in bone resorption. We chose Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans as prototype oral pathogens. We also tested the effects of Streptococcus gordonii, an oral commensal supragingival microorganism, considered a non-pathogen. Live bacteria were injected into subcutaneous tissue overlying the parietal bone of mice calvaria for 6 days. At the end of the experimental period, tissues overlying the calvaria were removed and analyzed for proinflammatory cytokine expression by Northern blotting. Cytokine mRNA was not detected in the tissue over the calvaria of control animals. In contrast, P. gingivalis and A. actinomycetemcomitans elicited mRNA expression of all three cytokines, TNFalpha being the highest (TNFalpha > > IL-1beta > IL-6). P. gingivalis was more potent than A. actinomycetemcomitans in inducing cytokine expression. In contrast, S. gordonii induced only low levels of mRNA for IL-1beta and TNFalpha but no IL-6 mRNA induction. These results suggest that oral microorganisms with access to host tissues elicit a battery of proinflammatory cytokines. There were clear differences in profiles and, interestingly, a commensal bacterium also stimulated bone resorptive cytokine expression in host tissues.