Medicine JournalFeeds

Peptidoglycan and lipopolysaccharide synergistically enhance bone resorption and osteoclastogenesis.

J Periodontal Res. 2012 Jan 29;

Authors: Kishimoto T, Kaneko T, Ukai T, Yokoyama M, Ayon Haro R, Yoshinaga Y, Yoshimura A, Hara Y

Abstract

Kishimoto T, Kaneko T, Ukai T, Yokoyama M, Ayon Haro R, Yoshinaga Y, Yoshimura A, Hara Y. Peptidoglycan and lipopolysaccharide synergistically enhance bone resorption and osteoclastogenesis. J Periodont Res 2012; doi: 10.1111/j.1600-0765.2011.01452.x.©2012 John Wiley & Sons A/S Background and Objective:  Peptidoglycan (PGN) and lipopolysaccharide (LPS) are bacterial cell wall constituents that are able to induce bone resorption by stimulating Toll-like receptor (TLR) 2 and TLR4, respectively. The fragments of PGN also stimulate inflammatory responses via nucleotide-binding oligomerization domain (NOD) 1 and NOD2, although there are differences in the NOD-stimulatory activities between gram-positive and gram-negative PGNs. The TLR and NOD signaling pathways are known to engage in cross-talk to enhance the production of inflammatory cytokines. In the present study, we investigated the effects of gram-negative and gram-positive PGNs on bone resorption and osteoclastogenesis in the presence or absence of LPS. Material and Methods:  We injected Escherichia coli PGN or Staphylococcus aureus PGN with or without LPS into mouse gingiva, and histopathologically assessed alveolar bone resorption by tartrate-resistant acid phosphatase staining. We also stimulated osteoclast precursors from mouse bone marrow macrophages with these PGNs in vitro and assessed osteoclastogenesis. The cells were also stimulated with synthetic ligands for NOD1; γ-D-glutamyl-meso-DAP NOD2; muramyl dipeptide or TLR2; Pam(3) CSK(4) with or without LPS to analyse the signaling cross-talk. Results:  S. aureus PGN, but not E. coli PGN, induced alveolar bone resorption, as did LPS. However, PGN from both sources significantly enhanced the bone resorption in the mice co-injected with LPS. Both types of PGNs induced osteoclastogenesis and accelerated osteoclastogenesis when the cells were co-stimulated with LPS in vitro. All synthetic ligands synergistically induced osteoclastogenesis by co-stimulation with LPS. Conclusion:  Gram-positive or gram-negative PGN worked synergistically with LPS to induce bone resorption and osteoclastogenesis, possibly by co-ordinating the effects of TLR2, NOD1, NOD2 and TLR4 signaling.

PMID: 22283724 [PubMed - as supplied by publisher]

The formation of immune complexes is involved in the acute phase of periodontal destruction in rats.

J Periodontal Res. 2012 Jan 29;

Authors: Kuramoto A, Yoshinaga Y, Kaneko T, Ukai T, Shiraishi C, Oshino K, Ichimura I, Hara Y

Abstract

Kuramoto A, Yoshinaga Y, Kaneko T, Ukai T, Shiraishi C, Oshino K, Ichimura I, Hara Y. The formation of immune complexes is involved in the acute phase of periodontal destruction in rats. J Periodont Res 2012; doi: 10.1111/j.1600-0765.2011.01453.x.©2012 John Wiley & Sons A/S Background and Objective:  Loss of clinical attachment and alveolar bone destruction are major symptoms of periodontitis, caused by not only the destructive effect of periodontopathic bacteria but also the overactive response of the host immune system against periodontal pathogens. The details of the participation of the immune system in the onset and progression of periodontitis are unclear. In this study, we attempted to determine whether the host immune system, and in particular the formation of immune complexes, is involved in the periodontal destruction. Material and Methods:  We applied ovalbumin or lipopolysaccharide (LPS) as antigens and their specific immunoglobulin G (IgG) antibodies purified from rat serum to rat gingival sulcus alternately. Loss of attachment, alveolar bone destruction and the numbers of inflammatory cells infiltrating the periodontal tissue and osteoclasts on the alveolar bone surface were investigated histometrically. The formation of immune complex was confirmed by immunohistological staining of complement C1qB. Results:  Loss of attachment and the presence of C1qB were observed histopathologically in both experimental groups. The group that had been treated with LPS and anti-LPS IgG showed greater loss of attachment. The number of inflammatory cells in the periodontal tissue was increased in both experimental groups, while osteoclasts at the alveolar bone crest were observed only in the group that had been treated with LPS and anti-LPS IgG. Conclusion:  In the present study, we showed that the formation of immune complex appears to be involved in the acute phase of periodontal destruction and that the biological activity of antigens is also important.

PMID: 22283745 [PubMed - as supplied by publisher]

A comparative in vitro evaluation of two different magnetic devices detecting the stability of osseo-integrated implants.

J Periodontal Res. 2012 Jan 18;

Authors: Geckili O, Bilhan H, Cilingir A, Mumcu E, Bural C

Abstract

Geckili O, Bilhan H, Cilingir A, Mumcu E, Bural C. A comparative in vitro evaluation of two different magnetic devices detecting the stability of osseo-integrated implants. J Periodont Res 2012. doi: 10.1111/j.1600-0765.2011.01462.x.©2012 John Wiley & Sons A/S Background and Objective:  It is unknown whether the resonance frequency analysis (RFA) measurements made by two different magnetic resonance frequency analysers are comparable. This in vitro study was designed to compare the RFA measurements made by the two magnetic resonance frequency analysers and to evaluate the intra- and interobserver reliability of the magnetic devices. Material and Methods:  Thirty-two implants were placed in four cow ribs. The RFA value of each implant was measured by five different examiners. The measurements were repeated five times, in both the buccal and mesial directions, for each implant at 2 h intervals, and the averages of registered implant stability quotient (ISQ) units were recorded as the buccal ISQ value and the mesial ISQ value for every implant. Results:  No statistically significant differences (p > 0.05) were observed between the RFA measurements made by the two magnetic devices. The intra-observer reliability of both devices was excellent, whereas the interobserver reliability of the devices was poor. Conclusion:  The results of the RFA measurements of both tested devices overlap. Although both devices show excellent intra-observer reliability, there are variations between the measurements of different examiners.

PMID: 22251236 [PubMed - as supplied by publisher]

The influence of enamel matrix derivative on the angiogenic activity of primary endothelial cells.

J Periodontal Res. 2011 Dec 29;

Authors: Kasaj A, Meister J, Lehmann K, Stratul SI, Schlee M, Stein JM, Willershausen B, Schmidt M

Abstract

Kasaj A, Meister J, Lehmann K, Stratul SI, Schlee M, Stein JM, Willershausen B, Schmidt M. The influence of enamel matrix derivative on the angiogenic activity of primary endothelial cells. J Periodont Res 2011; doi: 10.1111/j.1600-0765.2011.01456.x. © 2011 John Wiley & Sons A/S Background and Objective:  Angiogenesis plays a crucial role in early wound healing and tissue regeneration. Although enamel matrix derivative (EMD) has demonstrated the potential to stimulate periodontal regeneration, the biological effects of EMD on angiogenesis and underlying mechanisms have not been fully elucidated. The aim of the present study was to examine the angiogenic effects of EMD in vitro. Material and Methods:  Human umbilical vein endothelial cells (HUVECs) were used to assess the effect of EMD on proliferation, survival, adhesion and migration. The effect of EMD on HUVEC angiogenesis was assessed by a three-dimensional sprouting assay. In order to understand the signalling mechanism of altered cell proliferation of HUVECs caused by EMD, the phosphorylation status of ERK1/2 and of the serine/threonine protein kinase Akt was analysed by western blot using phospho-specific antibodies. Results:  The proliferation of HUVECs was stimulated by 50 μg/mL EMD, whereas higher concentrations (≥ 100 μg/mL) resulted in an increased apoptotic rate. The mitogenic response to EMD was associated with the activation of ERK1/2. Enamel matrix derivative did not affect cell adhesion, but all concentrations of EMD tested (0.1-250 μg/mL) promoted migration of HUVECs. Furthermore, EMD induced capillary-like sprout formation from HUVEC spheroids in a dose-dependent manner. Conclusion:  Our data indicate that EMD acts as a proangiogenic factor in vitro and, as such, might contribute to periodontal tissue regeneration by stimulation of vessel formation during wound healing.

PMID: 22212171 [PubMed - as supplied by publisher]

Editorial.

J Periodontal Res. 2012 Feb;47(1):1

Authors: Murakami S

PMID: 22220927 [PubMed - in process]

Investigation and quantification of key periodontal pathogens in patients with type 2 diabetes.

J Periodontal Res. 2012 Jan 3;

Authors: Field CA, Gidley MD, Preshaw PM, Jakubovics N

Abstract

Field CA, Gidley MD, Preshaw PM, Jakubovics N. Investigation and quantification of key periodontal pathogens in patients with type 2 diabetes. J Periodont Res 2012; doi: 10.1111/j.1600-0765.2011.01455.x. © 2012 John Wiley & Sons A/S Background and Objective:  Diabetes is a recognized risk factor for periodontitis. There are conflicting data regarding whether healthy diabetic patients or diabetic patients with chronic periodontitis have an altered subgingival microbiota compared with nondiabetic individuals. The aim of the present study was to detect quantitative differences in selected periodontopathogens in the subgingival plaque of diabetic patients using TaqMan quantitative PCR. Material and Methods:   Type 2 diabetes mellitus patients with (n = 9) or without chronic periodontal disease (n = 15) were recruited and matched to nondiabetic control subjects (n = 12 periodontally healthy, n = 12 chronic periodontitis). Subgingival plaque samples were collected from deep (> 4 mm probing depth) and shallow sites (≤ 3 mm probing depth) using paper points, and Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum and Porphyromonas gingivalis were quantified. Results:  Forty-eight subjects (69 samples) were recruited. Marked differences were seen in the levels of all three bacterial species, relative to the total bacterial population, according to periodontal health status. Using real-time quantitative PCR, bacterial counts for P. gingivalis were significantly higher in deep pockets of diabetic and nondiabetic subjects compared with periodontally healthy subjects (p < 0.05) but did not differ significantly between diabetics and nondiabetics. A. actinomycetemcomitans was detected in all groups in low quantities, and counts did not differ significantly between groups (p > 0.05). F. nucleatum was abundant in all groups, with no clear significant differences between groups. P. gingivalis was found in higher quantities in periodontitis than in periodontally healthy subjects (p < 0.05). Statistically significant positive correlations were identified between pocket depth and counts for all three species tested (p < 0.05). Conclusion:  A. actinomycetemcomitans, F. nucleatum and P. gingivalis were present in significantly different quantities and proportions in subgingival plaque, according to periodontal disease status. No significant differences were identified between the subgingival microbiota of type 2 diabetes mellitus patients compared with nondiabetic subjects.

PMID: 22220967 [PubMed - as supplied by publisher]

Analysis of proteins in human gingival crevicular fluid by mass spectrometry.

J Periodontal Res. 2012 Jan 3;

Authors: Kido J, Bando M, Hiroshima Y, Iwasaka H, Yamada K, Ohgami N, Nambu T, Kataoka M, Yamamoto T, Shinohara Y, Sagawa I, Nagata T

Abstract

Kido J, Bando M, Hiroshima Y, Iwasaka H, Yamada K, Ohgami N, Nambu T, Kataoka M, Yamamoto T, Shinohara Y, Sagawa I, Nagata T. Analysis of proteins in human gingival crevicular fluid by mass spectrometry. J Periodont Res 2012: doi: 10.1111/j.1600-0765.2011.01458.x. ©2012 John Wiley & Sons A/S Background and Objective:  Gingival crevicular fluid is a bodily fluid transuded from periodontal tissues into the gingival crevice and periodontal pocket, and contains many species of components. Proteins in gingival crevicular fluid have been studied as markers for periodontal diseases. Mass spectrometric analysis is used for the analyses of proteins, lipids, saccharides and metals, and expected as an approach for disease diagnosis. For better analysis of the protein components in gingival crevicular fluid, we investigated proteins in gingival crevicular fluid samples from the healthy gingival crevice and periodontal pocket using mass spectrometry. Material and Methods:  Gingival crevicular fluid samples were collected from subjects who gave their informed consent and were periodontally healthy or had diseased pockets. These samples were electrophoretically separated, and each fraction on the gels was analysed by nano liquid chromatography coupled with tandem mass spectrometry. Antimicrobial peptides detected in gingival crevicular fluid were confirmed by western blotting. Results:  One hundred and four proteins were detected in gingival crevicular fluid samples from both healthy sites and sites of periodontitis; 64 proteins were contained only in gingival crevicular fluid from healthy sites and 63 proteins were observed only in gingival crevicular fluid from periodontitis sites. These proteins were blood-, cytoskeleton-, immunity-, inflammation- and lipid-related proteins and enzymes. Some proteins, including ceruloplasmin, glycogen phosphorylase, glutathione S-transferase, phosphoglycerate mutase, psoriasin, S100A11 and resistin, were identified for the first time in gingival crevicular fluid. Antimicrobial peptides, such as lactoferrin, α1-antitrypsin, lipocalin, S100A7, S100A8, S100A9 and cathelicidin, were observed by mass spectrometry and western blotting. Conclusion:  Multiple protein components in gingival crevicular fluid were analysed at the same time using mass spectrometry, and this approach may be useful for the diagnosis of periodontal diseases.

PMID: 22220998 [PubMed - as supplied by publisher]

Subgingival microbiota in adult Down syndrome periodontitis.

J Periodontal Res. 2012 Jan 3;

Authors: Khocht A, Yaskell T, Janal M, Turner BF, Rams TE, Haffajee AD, Socransky SS

Abstract

Khocht A, Yaskell T, Janal M, Turner BF, Rams TE, Haffajee AD, Socransky SS. Subgingival microbiota in adult Down syndrome periodontitis. J Periodont Res 2012; doi: 10.1111/j.1600-0765.2011.01459.x. © 2012 John Wiley & Sons A/S Background and Objective:  The subgingival microbiota in Down syndrome and non-Down syndrome adults receiving periodic dental care was examined for 40 bacterial species using checkerboard DNA-DNA hybridization and the results were related to clinical periodontal attachment loss. Material and Methods:  A total of 44 Down syndrome, 66 non-Down syndrome mentally retarded and 83 mentally normal adults were clinically evaluated. This involved, for each subject, the removal of subgingival specimens from three interproximal sites on different teeth; all subgingival samples per subject were then pooled and assessed for the presence and levels of 40 bacterial species using species-specific whole-genomic DNA probes and checkerboard DNA-DNA hybridization. Significant group differences in species proportions averaged across subjects were evaluated using the Kruskal-Wallis test, and associations between subgingival species and mean subject attachment loss within Down syndrome and non-Down syndrome subject groups were quantified using Pearson correlation and multiple linear regression analysis. Results:  Down syndrome subjects exhibited greater attachment loss than non-Down syndrome subjects (p = 0.05). Most microbial species were present in Down syndrome subjects at levels similar to non-Down syndrome subjects, except for higher proportions of Selenomonas noxia, Propionibacterium acnes, Streptococcus gordonii, Streptococcus mitis and Streptococcus oralis in Down syndrome subjects compared with non-Down syndrome study subjects, higher proportions of Treponema socranskii in Down syndrome subjects compared with non-Down syndrome mentally retarded subjects, and higher proportions of Streptococcus constellatus in Down syndrome subjects compared with mentally normal subjects. Down syndrome adults classified with periodontitis revealed higher subgingival levels of T. socranskii than Down syndrome subjects with no periodontitis (p = 0.02). Higher subgingival proportions of S. constellatus, Fusobacterium nucleatum ssp. nucleatum, S. noxia and Prevotella nigrescens showed significant positive correlations (r = 0.35-0.42) and higher proportions of Actinomyces naeslundii II and Actinomyces odontolyticus showed negative correlations (r = -0.36 to -0.40), with increasing mean subject attachment loss in Down syndrome adults. Conclusion:  Individuals with Down syndrome show higher levels of some subgingival bacterial species and specific associations between certain subgingival bacterial species and loss of periodontal attachment. These findings are consistent with the notion that certain subgingival bacteria may contribute to the increased level of periodontal disease seen in Down syndrome individuals and raise the question as to the reason for increased colonization in Down syndrome.

PMID: 22221039 [PubMed - as supplied by publisher]

Acute myocardial infarction elevates serine protease activity in saliva of patients with periodontitis.

J Periodontal Res. 2011 Dec 19;

Authors: Mäntylä P, Buduneli E, Emingil G, Tervahartiala T, Pussinen PJ, Barış N, Akıllı A, Atilla G, Sorsa T

Abstract

Mäntylä P, Buduneli E, Emingil G, Tervahartiala T, Pussinen PJ, Barış N, Akıllı A, Atilla G, Sorsa T. Acute myocardial infarction elevates serine protease activity in saliva of patients with periodontitis. J Periodont Res 2011; doi: 10.1111/j.1600-0765.2011.01439.x © 2011 John Wiley & Sons A/S Background and Objective:  There are indications that acute myocardial infarction (AMI) may have an effect on the oral environment, which is reflected in the expression of salivary and gingival proteinases. According to our knowledge, no studies have been carried out to investigate the effect of AMI on the activities of two major tissue-destructive serine protease and microbial effectors, elastase and cathepsin G, produced by oral fluid polymorphonuclear granulocytes (PMN). Therefore, we compared the activities of elastase and cathepsin G in saliva from patients with AMI and from systemically healthy subjects (non-AMI) with similar periodontal conditions. Material and Methods:  A total of 92 patients (47 AMI and 28 non-AMI patients with gingivitis or periodontitis, and 17 systemically and periodontally healthy subjects as a control group) were recruited. Clinical periodontal measurements were recorded, and stimulated whole-saliva samples were collected. The patients with AMI were clinically examined within 3-4 d after admission to the coronary care unit. The activities of saliva neutrophil elastase and cathepsin G were measured after collection, at specific time-points during incubation (from baseline to 23 h) by specific synthetic peptide substrate assays. Results:  The saliva of patients with AMI and periodontitis had a significant trend for the highest elastase activities among the study groups. Elastase and cathepsin G activities correlated significantly with each other in the AMI periodontitis group (r = 0.8, p < 0.01). In a logistic regression analysis, the level of salivary elastase activity associated significantly with periodontitis. Conclusion:  AMI may be reflected in PMN serine protease elastase activity in saliva, despite its strong association with periodontitis.

PMID: 22181012 [PubMed - as supplied by publisher]

Predominant bacterial species in subgingival plaque in dogs.

J Periodontal Res. 2011 Dec 19;

Authors: Dahlén G, Charalampakis G, Abrahamsson I, Bengtsson L, Falsen E

Abstract

Dahlén G, Charalampakis G, Abrahamsson I, Bengtsson L, Falsen E. Predominant bacterial species in subgingival plaque in dogs. J Periodont Res 2011; doi: 10.1111/j.1600-0765.2011.01440.x.©2011 John Wiley & Sons A/S Background and Objective:  The dog has been used extensively for experimental and microbiological studies on periodontitis and peri-implantitis without detailed knowledge about the predominant flora of the subgingival plaque. This study was designed to evaluate the predominant cultivable bacterial species in dogs and compare them phenotypically and genotypically with corresponding human species. Material and Methods:  Four subgingival samples were taken from two upper premolars in each of six Labrador retrievers. The samples from each dog were processed for anaerobic culture. From the samples of each dog, the five or six predominating bacteria based on colony morphology were selected and pure cultured. Each of the strains was characterized by Gram stain, anaerobic/aerobic growth and API-ZYM test. Eighteen strains showing clear-cut phenotypic differences were further classified based on DNA sequencing technology. Cross-reactions of DNA probes from human and dog strains were also tested against a panel of both human and dog bacterial species. Results:  Thirty-one strains in the dogs were isolated and characterized. They represented 21 different species, of which six belonged to the genus Porphyromonas. No species was found consistently in the predominant flora of all six dogs. Porphyromonas crevioricanis and Fusobacterium canifelinum were the two most prevalent species in predominant flora in dogs. DNA probes from human and dog species cross-reacted to some extent with related strains from humans and dogs; however, distinct exceptions were found. Conclusion:  The predominant cultural subgingival flora in dogs shows great similarities with the subgingival bacteria from humans at the genus level, but distinct differences at the species level; however, a genetic relatedness could be disclosed for most strains investigated.

PMID: 22181039 [PubMed - as supplied by publisher]