Association between Volatile Sulfur Compounds Prevotella intermedia and Matrix Metalloproteinase-8 Expression

Abstract Objective: To determine the correlation between levels of methyl mercaptan (CH3SH) hydrogen sulfide (H2S), the proportion of Prevotella intermedia (Pi), and matrix metalloproteinase-8 (MMP-8) gene expression levels in periodontitis patients accompanied by halitosis. Material and Methods: Samples were obtained from gingival crevicular fluid (GCF) in the deepest pocket and by swabbing in the tongue coating area in patients with periodontitis presenting with halitosis (n = 23) and healthy subjects as controls (n = 7). The values of CH3SH and H2S were obtained using Oral Chroma. The proportion of Pi and MMP-8 expression levels were evaluated using PCR-RT. All the result was statistically analyzed using SPSS software. Results: The levels of CH3SH and H2S in participants with PD ≥ 6 mm showed a robust negative correlation with the proportion of P. intermedia in GCF and tongue coating. No statistically significant association was detected between CH3SH and H2S levels and MMP-8 expression levels (p>0.05). Conclusion: There is no association between CH3SH and H2S levels, the proportion of P. intermedia, and MMP-8 expression in patients with periodontitis accompanied by halitosis (AU).

The inhibitory effect of ozone water on bad breath pathogens in vitro / 实用口腔医学杂志

Objective: To study the inhibitory effect of ozone water on bad breath pathogens in vitro. Methods: In vitro cultured bad breath pathogens Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi) and Fusobacterium nucleatum (Fn) were identified by Gram stain and a PCR test. Ozonated water by was prepared by ozone generator and the concentration of ozone in water was measured using iodine titration. Artificial saliva was used to observe its interference on ozone function. Results: Gram stain and PCR results were consisted with strain characteristics. The ozone concentration of ozonated water reached to the maximum of 0. 2 mg/L. Ozone water with the concentration was 0. 05, 0. 1 and 0. 2 mg/L inhibited the proliferation of Pg, Pi and Fn. But the inhibitory effect was weakened when the concentration decreased. The artificial saliva reduced the effect of ozone water. Conclusion: The Pg, Pi and Fn can be inhibited by ozone water. Artificial saliva may reduce the effects of ozone water on the bacteria.

Genome sequence of Prevotella intermedia SUNY aB G8-9K-3, a biofilm forming strain with drug-resistance

Abstract Prevotella intermedia has long been known to be as the principal etiologic agent of periodontal diseases and associated with various systemic diseases. Previous studies showed that the intra-species difference exists in capacity of biofilm formation, antibiotic resistance, and serological reaction among P. intermedia strains. Here we report the genome sequence of P. intermedia SUNY aB G8-9K-3 (designated ATCC49046) that displays a relatively high antimicrobial resistant and biofilm-forming capacity. Genome sequencing information provides important clues in understanding the genetic bases of phenotypic differences among P. intermedia strains.

Red fluorescence of oral bacteria is affected by blood in the growth medium / 대한구강보건학회지

OBJECTIVES: Dental plaque emits red fluorescence under a visible blue light near the ultra-violet end of the light spectrum. The fluorescence characteristics of each microorganism have been reported in several studies. The aim of this study was to evaluate changes in red fluorescence of oral microorganisms that is affected by blood in the culture media. METHODS: The gram-positive Actinomyces naeslundii (AN, KCTC 5525) and Lactobacillus casei (LC, KCTC 3109) and gram negative Prevotella intermedia (PI, KCTC 3692) that are known to emit red fluorescence were used in this study. Each bacterium was activated in broth and cultivated in different agar media at 37℃ for 7 days. Tryptic soy agar with hemin and vitamin K3 (TSA), TSA with sheep blood (TSAB), basal medium mucin (BMM) medium, and BMM with sheep blood (BMMB) were used in this study. Fluorescence due to bacterial growth was observed under 405-nm wavelength blue light using the quantitative light-induced fluorescence-digital (QLF-D) device. The red, green, and blue fluorescence values of colonies were obtained using image-analysis software and the red to green ratio (R/G value) and red to total RGB ratio (R/RGB value) were calculated for quantitative comparison. RESULTS: The QLF-D images of the AN, LC, and PI colonies showed red fluorescence in all media, but the fluorescence of all bacteria was reduced in TSA and BMM media, compared with in TSAB and BMMB media. Both the R/G and the R/RGB values of all bacteria were significantly reduced in growth media without blood (P<0.001). CONCLUSIONS: Based on this in vitro study, it can be concluded that red fluorescence of oral bacteria can be affected by growth components, especially blood. Blood-containing medium could be a significant factor influencing red fluorescence of oral bacteria. It can be further hypothesized that bleeding in the oral cavity can increase the red fluorescence of dental plaque.

Development of Quantitative Real-Time PCR Primers for Detection of Prevotella intermedia

Prevotella intermedia-specific quantitative real-time PCR (qPCR) primers were previously designed based on the nucleotide sequences of RNA polymerase beta-subunit gene (rpoB). However, the several clinical strains isolated from Korean populations are not detectable by the qPCR primers. The purpose of this study was to develop new P. intermedia-specific qPCR primers based on the rpoB. The specificity of the primers was determined by conventional PCR with 12 strains of P. intermedia and 52 strains (52 species) of non-P. intermedia bacteria. The sensitivity of primers was determined by qPCR with serial dilutions of the purified genomic DNAs (40 ng to 4 fg) of P. intermedia ATCC 25611T. The data indicated that only P. intermedia strains were detected by the P intermedia-specific qPCR primers (RTPiF2/RTPiR2); in addition, as little as 40 fg of P. intermedia genomic DNA could be detected. These results suggest that these qPCR primers are useful in detecting P. intermedia from the bacterial infectious lesions including dental plaque and oral tissue lesions.

Prevotella intermedia: uma breve revisão / Prevotella intermedia: A brief review

Prevotella intermedia é um microrganismo anaeróbio Gram negativo, considerado um dos agentes etiológicos de doenças periodontais. Tendo em vista que o biofilme subgengival é um dos seus principais habitats, qualquer quebra na homeostase do meio pode favorecer seu desenvolvimento e consequente dano aos tecidos atingidos. Diversas pesquisas vêm sendo realizadas a fim de identificar o papel deste microrganismo nas doenças periodontais. Assim, este trabalho teve por objetivo revisar a literatura para coletar informações sobre as características e efeitos de Prevotella intermedia no contexto saúde-doença periodontal. A busca foi realizada nas bases de dados PubMed e Lilacs, bem como através de uma busca aleatória. De um total de 47 artigos incluídos, alguns principais resultados puderam ser destacados: Prevotella intermedia está fortemente associada ao quadro de doenças periodontais e suas características favorecem o acometimento e intensificação de doenças diversas. Além disso, este microrganismo é capaz de produzir pigmentos e uma variedade de enzimas as quais favorecem danos aos tecidos periodontais. Existem várias características que aumentam a patogenicidade e virulência deste microrganismo, como por exemplos a sua cápsula polissacarídica, a presença de enzimas protetoras contra o oxigênio, a presença e produção de proteases, além da estimulação de fatores de crescimento no hospedeiro. Não há consenso na literatura acerca da relação de causa-efeito entre presença de Prevotella intermedia e diabetes. Contudo, este microrganismo parece estar envolvido no quadro de pacientes HIV positivo. Por fim, é importante salientar que Prevotella intermedia pode adquirir resistência a alguns tipos de antibióticos, e, por isso, o seu controle é um desafio à clínica atual...

Prevotella intermedia is a Gram negative anaerobic microorganism, considered one of the etiologic agents of periodontal diseases. Taking into account that the subgingival biofilm is its major habitat, any break of the environment homeostasis may lead to the development of the microorganism and consequent damage to the surrounding tissues. Several researches have been conducted in order to identify the role of this microorganism in the periodontal diseases. Thus, this study aimed to review the literature in an attempt to collect information about the characteristics and effects of Prevotella intermedia in the periodontal healthdisease context. The search was performed in the PubMed and Lilacs databases, as well as under a random search. From a total of 47 included articles, some major results could be drawn: Prevotella intermedia is strongly related to the occurrence of periodontal diseases, and its characteristics lead to the incidence of several diseases. Moreover, this microorganism is able to produce pigments and a variety of enzymes, which potentiate the damage of periodontal tissues. There are several characteristics that increase the pathogenicity and virulence of this microorganism, including the polyssacharidic capsule, the presence of protective enzymes against oxygen, the presence and production of proteases, as well as the stimulation of grow factors in the host. There is no consensus in the literature regarding the cause-effect relationship between the presence of Prevotella intermedia and diabetes. However, this microorganism seems to be involved in the occurrence of HIV-positive people. Lastly, it is worth to mention that Prevotella intermedia may acquire strength to some antibiotic types, and, therefore, its control is a challenge to the current clinic...

Effect of quercetin on the production of nitric oxide in murine macrophages stimulated with lipopolysaccharide from Prevotella intermedia

PURPOSE: Nitric oxide (NO) is a short-lived bioactive molecule that is known to play an important role in the pathogenesis of periodontal disease. In the current study, we investigated the effect of the flavonoid quercetin on the production of NO in murine macrophages activated with lipopolysaccharide (LPS) from Prevotella intermedia, a pathogen related to inflammatory periodontal disease, and tried to elucidate the underlying mechanisms of action. METHODS: LPS was isolated from P. intermedia ATCC 25611 cells by the standard hot phenol-water method. The concentration of NO in cell culture supernatants was determined by measuring the accumulation of nitrite. Inducible NO synthase (iNOS) and heme oxygenase-1 (HO-1) protein expression, phosphorylation of c-Jun N-terminal kinase (JNK) and p38, inhibitory kappaB (IkappaB)-alpha degradation, and signal transducer and activator of transcription 1 (STAT1) phosphorylation were analyzed via immunoblotting. RESULTS: Quercetin significantly attenuated iNOS-derived NO production in RAW246.7 cells activated by P. intermedia LPS. In addition, quercetin induced HO-1 protein expression in cells activated with P. intermedia LPS. Tin protoporphyrin IX (SnPP), a competitive inhibitor of HO-1, abolished the inhibitory effect of quercetin on LPS-induced NO production. Quercetin did not affect the phosphorylation of JNK and p38 induced by P. intermedia LPS. The degradation of IkappaB-alpha induced by P. intermedia LPS was inhibited when the cells were treated with quercetin. Quercetin also inhibited LPS-induced STAT1 signaling. CONCLUSIONS: Quercetin significantly inhibits iNOS-derived NO production in murine macrophages activated by P. intermedia LPS via anti-inflammatory HO-1 induction and inhibition of the nuclear factor-kappaB and STAT1 signaling pathways. Our study suggests that quercetin may contribute to the modulation of host-destructive responses mediated by NO and appears to have potential as a novel therapeutic agent for treating inflammatory periodontal disease.

Inhibition of oral pathogens and collagenase activity by seaweed extracts.

Fifty-seven species of common seaweed from the Coast of Korea were screened for antimicrobial (i.e. inhibition of Prevotella intermedia and Porphyromonas gingivalis growth) activity. As a source of bioactive compounds, seaweeds can produce many secondary metabolites with a variety of activities. Using the agar diffusion method, only 17 species (29.8%) showed inhibitory activity. Of these, methanol extracts of Enteromorpha linza, Sargassum sagamianum, and Ulva pertusa showed strong inhibitory effects against both P. intermedia and P. gingivalis. The MIC values of E. linza, S. sagamianum, and U. pertusa extracts against P. intermedia were 625, 78 and 625 Ag ml-1 and those against P. gingivalis were 312, 156 and 625 Ag ml-1, respectively. When these three species’ extracts were separated into five fractions according to their polarity, the main active agents were determined to be phenolic compounds. We then compared the antimicrobial activities of these phenolic compounds against various periodontal pathogens using a MIC test. Phenolic compound containing extracts at concentrations of 10 to 100 Ag ml-1 showed a moderate to significant inhibitory effect on collagenase 1, 2 and 3 activity.

Curcumin suppresses the production of interleukin-6 in Prevotella intermedia lipopolysaccharide-activated RAW 264.7 cells

PURPOSE: Curcumin is known to exert numerous biological effects including anti-inflammatory activity. In this study, we investigated the effects of curcumin on the production of interleukin-6 (IL-6) by murine macrophage-like RAW 264.7 cells stimulated with lipopolysaccharide (LPS) from Prevotella intermedia, a major cause of inflammatory periodontal disease, and sought to determine the underlying mechanisms of action. METHODS: LPS was prepared from lyophilized P. intermedia ATCC 25611 cells by the standard hot phenol-water method. Culture supernatants were collected and assayed for IL-6. We used real-time polymerase chain reaction to detect IL-6 mRNA expression. IkappaB-alpha degradation, nuclear translocation of NF-kappaB subunits, and STAT1 phosphorylation were characterized via immunoblotting. DNA-binding of NF-kappaB was also analyzed. RESULTS: Curcumin strongly suppressed the production of IL-6 at both gene transcription and translation levels in P. intermedia LPS-activated RAW 264.7 cells. Curcumin did not inhibit the degradation of IkappaB-alpha induced by P. intermedia LPS. Curcumin blocked NF-kappaB signaling through the inhibition of nuclear translocation of NF-kappaB p50 subunit. Curcumin also attenuated DNA binding activity of p50 and p65 subunits and suppressed STAT1 phosphorylation. CONCLUSIONS: Although further study is required to explore the detailed mechanism of action, curcumin may contribute to blockade of the host-destructive processes mediated by IL-6 and appears to have potential therapeutic values in the treatment of inflammatory periodontal disease.

Strain-specific PCR Primers for the Detection of Prevotella intermedia ATCC 49046

The aim of this study was to develop Prevotella intermedia ATCC 49046-specific PCR primers designed based on the nucleotide sequence of a DNA probe Pig28. The strain-specificity of the PCR primers, Pig28-F1/Pig28-R1, was confirmed with 9 strains of P. intermedia and 25 strains (15 species) of Prevotella species. The detection limit of the PCR primers was 2 pg of the purified genomic DNA of P. intermedia ATCC 49046. These PCR primers were found to be useful for identifying P. intermedia ATCC 49046, particularly for determining the authenticity of the strain.

Detection of Prevotella intermedia and Prevotella nigrescens using Pn17 and Pn34 DNA Probes

The DNA probes Pn17 and Pn34 were evaluated for their ability to specifically detect clinical strains of P. intermedia and P. nigrescens from a Korean population by dot blot hybridization. These probes were sequenced by extension termination and their specificity was determined by Southern blot analysis. The results revealed that the Pn17 sequence (2,517 bp) partially encodes an RNA polymerase beta subunit (rpoB) and that Pn34 (1,918 bp) partially encodes both rpoB (1-169 nts) and the RNA polymerase beta subunit (rpoB'; 695-1918 nts). These probes hybridized with both HindIII- and PstI-digested genomic DNAs from the strains of P. intermedia and P. nigrescens used in this study. Interestingly, each of the hybrid bands generated from the HindIII-digested genomic DNAs of the two bacterial species could be used to distinguish between them via restriction fragment length polymorphism. These results thus indicate that Pn17 and Pn34 can simultaneously detect P. intermedia and P. nigrescens.

Leptin potentiates Prevotella intermedia lipopolysaccharide-induced production of TNF-alpha in monocyte-derived macrophages

PURPOSE: In addition to regulating body weight, leptin is also recognized for its role in the regulation of immune function and inflammation. The purpose of this study was to investigate the effect of leptin on Prevotella (P.) intermedia lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-alpha production in differentiated THP-1 cells, a human monocytic cell line. METHODS: LPS from P. intermedia ATCC 25611 was prepared by the standard hot phenol-water method. THP-1 cells were incubated in the medium supplemented with phorbol myristate acetate to induce differentiation into macrophage-like cells. The amount of TNF-alpha and interleukin-8 secreted into the culture medium was determined by enzyme-linked immunosorbent assay (ELISA). TNF-alpha and Ob-R mRNA expression levels were determined by semi-quantitative reverse transcription-polymerase chain reaction analysis. RESULTS: Leptin enhanced P. intermedia LPS-induced TNF-alpha production in a dose-dependent manner. Leptin modulated P. intermedia LPS-induced TNF-alpha expression predominantly at the transcriptional level. Effect of leptin on P. intermedia LPS-induced TNF-alpha production was not mediated by the leptin receptor. CONCLUSIONS: The ability of leptin to enhance P. intermedia LPS-induced TNF-alpha production may be important in the establishment of chronic lesion accompanied by osseous tissue destruction observed in inflammatory periodontal disease.

Aggregatibacter Actinomycetemcomitants And Prevotella Intermedia In Advanced Chronic Periodontis Patients

This cross-sectional study was carried out to identify A. actinomycetemcomitans and P. intermedia in the subgingival plaque of three ethnic groups (Malays, Chinese and Indians) in a selected group of adult Malaysians with advanced Chronic Periodontitis and to correlate these findings with their periodontal status. Thirty periodontally diseased adults were age, gender and ethnically matched with 30 healthy individuals. Clinical parameters were assessed for all. Subgingival plaque samples were collected for identification of A. actinomycetemcomitans and P. intermedia using polymerase chain reaction. Prevalence for P. intermedia (83.3%) was high and A. actinomycetemcomitans (6.7%) low in the total subject population. P. intermedia and A. actinomycetemcomitans were more prevalent in diseased (86.7%, 10% respectively) than in healthy (80%, 3.33% respectively) subjects. A. actinomycetemcomitans was detected in 15% Indians, 5% Malays but none of the Chinese subjects whereas P. intermedia was detected in 90% Malays, 85% Indians and 75% Chinese subjects. No significant association between presence of A. actinomycetemcomitans and P. intermedia with race and periodontal disease status was found. Only A. actinomycetemcomitans had a significant association with clinical attachment level (CAL) (p < 0.05). In conclusion, in this small subject group, none of the pathogens were associated with race and periodontal disease status and only A. actinomycetemcomitans had a significant association with CAL.

Antimicrobial effect of MTAD, Tetraclean, Cloreximid, and sodium hypochlorite on three common endodontic pathogens.

Objectives: The aim of this in vitro study was to evaluate the antimicrobial action of BioPure MTAD (Dentsply Tulsa Dental, Johnson City, TN), Tetraclean, Cloreximid (a mixture of Chlorhexidine (CHX) digluconate and Cetrimide), and 5.25% NaOCl (Ogna Laboratori Farmaceutici, Milano, Italy) against selected endodontic pathogens (Enterococcus faecalis, Porphyromonas gingivalis, and Prevotella intermedia). Materials and Methods: The agar plate diffusion procedure was used to observe the antimibrobial activity of irrigants. Results: Statistical analysis revealed significant effects of the different irrigants on the bacteria colonies. Treatment with 5.25% NaOCl induced a larger zone of microbial inhibition in Prevotella intermedia and Porphyromonas gingivalis (Tukey HSD post-test, P = 0.0001) when compare to MTAD, Tetraclean and CHX. Anyway, MTAD and Tetraclean were more effective to inhibit bacterial growth compared to CHX (P < 0.0001, Tukey HSD post-test). Furthermore, post hoc analysis revealed that MTAD and Tetraclean induced the largest zone of microbial inhibition of Enterococcus faecalis cultured under both aerobic and anaerobic conditions, when compared with 2% CHX and NaOCl (P < 0.0001, Tukey HSD post-test). The control group showed no microbial inhibition. Conclusion: 5.25% NaOCl showed a high antimicrobial activity against anaerobic bacteria. MTAD and Tetraclean showed a high action against both, strictly anaerobic and facultative anaerobic bacteria. Chlorexidine + Cetrimide (Cloreximid) showed the lowest antibacterial activity against both, facultative and strictly anaerobic bacteria tested.

Interleukin-8 production and interleukin-8 mRNA expression induced by lipopolysaccharides from Prevotella intermedia and Prevotella nigrescens in monocyte-derived macrophages / 대한치주과학회지

PURPOSE: Interleukin-8 (IL-8) is an important mediator of immune and inflammatory reactions and is produced by a variety of different cell types. This study was undertaken to investigate the effects of lipopolysaccharides (LPSs) from Prevotella intermedia and Prevotella nigrescens, the major causes of inflammatory periodontal disease, on the production of IL-8 and the expression of IL-8 mRNA in differentiated THP-1 cells, a human monocytic cell line. METHODS:LPSs from P. intermedia ATCC 25611 and P. nigrescens ATCC 33563 were prepared by the standard hot phenol-water method. THP-1 cells were incubated in the medium supplemented with phorbol myristate acetate to induce differentiation into macrophage-like cells. RESULTS: We found that LPS preparations from P. intermedia and P. nigrescens can induce IL-8 mRNA expression and stimulate the release of IL-8 in differentiated THP-1 cells without additional stimuli. CONCLUSIONS: There are no previous reports of the ability of P. intermedia and P. nigrescens LPS to stimulate the release of IL-8, and the present study clearly shows, for the first time, that LPSs from P. intermedia and P. nigrescens fully induced IL-8 mRNA expression and IL-8 production in differentiated human monocytic cell line THP-1. The ability of P. intermedia and P. nigrescens LPS to promote the production of IL-8 may be important in the pathogenesis of inflammatory periodontal disease.

In vitro antibacterial activity of domestic-made water-soluble propolis against oral anaerobic bacteria from the infected root canal / 重庆医科大学学报

Objective:To evaluate bacteriostasis effect of domestic-made water-soluble propolis on prevotella intermedia(Pi),fu-sobacterium nucleatum(Fn)and mixture bacteria of Pi and Fn in vitro.Methods:With agar dilution,minimal bactericidal con-centrations(MBC)of propolis for Fn,Pi and mixture bacteria were determined.Results:MBC of propolis for Fn,Pi or mixture bacteria were 0.025%,0.025%,0.05% respectively.Conclusion:Propolis shows the favourable antibacterial activity against the main anaerobic bacterium in infectious root canal which it has a value of application for disinfecting root canal.

Isolation and Partial Characterization of Hemin-binding Cell Envelope Proteins from Porphyromonas gingivalis, Prevotella intermedia, and Prevotella nigrescens / 대한치주과학회지

The results of this study confirm that the availability of hemin influences the expression of selected membrane proteins of Porphyromonas gingivalis, Prevotella intermedia, and Prevotella nigrescens. A 30 kDa (heated 24 kDa) hemin-binding protein whose expression is hemin regulated was identified and purified in P. gingivalis. A strong hemin-binding function was found by LDS-PAGE and TMBZ staining when P. gingivalis cells were grown under hemin-limited conditions. A 50 kDa cell envelope associated protein, whose expression is hemin regulated, is considered to be a putative hemin binding protein from P. intermedia and P. nigrescens, respectively. N-terminal amino acid sequence analysis of CNBr-digested 24 kDa hemin binding protein from P. gingivalis revealed that this protein belongs to a new, so far undescribed hemin-binding class of proteins. N-terminal amino acid sequence of a 50 kDa putative hemin binding protein from P. intermedia was identical with Enolase from Streptococcus intermedia. Work is in progress to further characterize the molecular structure of these proteins.

Suppression of nitric oxide and interleukin-6 production by methanol extract of Sophorae Flos in macrophage cells / 대한치주과학회지

Both nitric oxide (NO) and interleukin-6 (IL-6) have been thought to have a role in the pathogenesis of inflammatory periodontal disease as it does in other inflammatory diseases, and the inhibitors of NO and IL-6 production have been considered as potential anti-inflammatory agents. In this study, we evaluated methanol extract of Sophorae Flos for inhibition of NO and IL-6 production in Prevotella intermedia LPS-induced mouse macrophages RAW264.7 cells. Dried Sophorae Flos was sliced, and extracted with 100% methanol. LPS from P. intermedia ATCC 25611 was prepared by the standard hot phenol-water method. NO production was assayed by measuring the accumulation of nitrite in culture supernatants and IL-6 was measured using mouse IL-6 ELISA kit. Western blot analysis of iNOS and analysis of reverse transcription (RT)-PCR products were carried out. The methanol extract of Sophorae Flos concentration-dependently reduced the production of NO and the expression of iNOS protein and mRNA in RAW264.7 cells treated with P. intermedia LPS. Sophorae Flos also suppressed IL-6 production and the expression of IL-6 mRNA in RAW264.7 cells stimulated by P. intermedia LPS. The inhibition of NO and IL-6 production by Sophorae Flos may be useful in the therapy of inflammatory diseases such as periodontitis. This hypothesis, however, remains to be tested.

Expression of mRNA for matrix metalloproteinases and tissue inhibitors of metalloproteinases in human gingival and periodontal ligament fibroblasts treated with lipopolysaccharide from Prevotella intermedia / 대한치주과학회지

Matrix metalloproteinases (MMPs) are a family of host-derived proteolytic enzymes and implicated in the remodeling and degradation of extracellular matrix under both physiological and pathological conditions. Connective tissue degradation in periodontal diseases is thought to be due to excessive MMP activities over their specific inhibitors. The effects of lipopolysaccharide (LPS) from Prevotella intermedia, one of the major putative pathogens of periodontitis, on the expression of mRNA for MMPs and tissue inhibitors of metalloproteinases (TIMPs) in human gingival and periodontal ligament fibroblasts were examined by reverse transcriptase-polymerase chain reaction (RT-PCR). The expression of mRNAs encoding MMP-1, -2, -3, -10, and -14 was increased in human gingival fibroblasts treated with P. intermedia LPS, whereas MMP-11 and TIMP-2 mRNA expression was decreased in these cells stimulated with LPS. P. intermedia LPS increased the MMP-1, -2, -10, -11, and -14 mRNA expression and decreased TIMP-1 and -2 mRNA expression in human periodontal ligament fibroblasts. These findings imply that P. intermedia LPS may play an important role in the connective tissue degradation in periodontitis.

Chemical and Immunobiological Characterization of Lipopolysaccharides from Prevotella intermedia and Prevotella nigrescens / 대한치주과학회지

The purpose of this study was to assess some biological activities of lipopolysaccharides (LPSs) from P. intermedia and P. nigrescens. LPS was prepared by the standard hot phenol-water method. NO production was assayed by measuring the accumulation of nitrite in culture supernatants. TNF-alpha production was determined by enzyme-linked immunosorbent assay. Western blot analysis of iNOS and analysis of reverse transcription (RT)-PCR products were carried out. LPS from P. intermedia demonstrated higher KDO content than those from two stains of P. nigrescens. LPSs from P. intermedia and P. nigrescens were mitogenic for spleen cells of BALB/C mouse. The present study clearly shows that LPSs from P. intermedia and P. nigrescens fully induced iNOS expression and NO production in RAW264.7 cells in the absence of other stimuli. Moreover, LPSs from P. intermedia and P. nigrescens clearly induced TNF-alpha production in RAW264.7 cells. The biological activities of LPS from P. intermedia was found to be comparable to those of P. nigrescens LPS. The ability of LPSs from P. intermedia and P. nigrescens to promote the production of NO and TNF-alpha may be important in the pathogenesis of inflammatory periodontal disease.