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Background and Objectives: Periodontitis, the most common chronic inflammation characterized by persistent alveolar bone resorption in the periodontitis, affects almost half of the adult population worldwide. Oxidative stress is one of the pathophysiological mechanisms underlying periodontitis, which affects the occurrence and development of periodontitis. Exosomes are increasingly recognized as vehicles of intercellular communication and are closely related to periodontitis. However, the effects of oxidative stress on exosome secretion and the specific mechanisms remain elusive in human periodontal ligament cells (hPDLCs). The relationship between exosome secretion and the osteogenic differentiation of hPDLCs also needs to be investigated. Methods: Isolated PDLSCs were identified using flow cytometry. Osteogenesis was measured using alizarin red staining and ALP staining. Expression of exosomal markers and PRMT1 was analyzed using western blot. Immunofluorescence was used to measure exosome uptake and the expression of EEA1. Results: The secretion capacity of exosomes was markedly suppressed under oxidative stress. Protein arginine methyltransferase 1 (PRMT1) has been strongly associated with both oxidative stress and inflammation, and PRMT1 was significantly upregulated under oxidative stress conditions. Lentivirus‐mediated overexpression of PRMT1 caused a significant reduction in the secretion of exosomes, but multivesicular bodies (MVBs) containing a large number of intraluminal vesicles (ILVs) were increased. Rab11a and Rab27a expression, which mediate MVBs fusion with cell membranes, decreased, although this phenomenon was restored after knocking down PRMT1 expression under oxidative stress. Conclusions: These results indicated that PRMT1 mediated a decrease in exosome secretion of hPDLCs. The decrease in Rab11a and Rab27a leads to a large accumulation of MVBs in cells and is one of the main reasons for impaired exosome secretion. The decrease in osteogenic differentiation of hPDLCs caused by H2O2 may originate in part from the inhibition of exosome secretion. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to determine differences in GCF and serum levels of fractalkine/CX3CL1 and its receptor/ CX3CR1 between the patients with stage III/grade B periodontitis and periodontally healthy subjects. Background: Fractalkine (CX3CL1), the only member of CX3C chemokine family, is involved in the pathogenesis of several systemic inflammatory diseases' disorders including rheumatoid arthritis, cardiovascular diseases, tonsillitis, and diabetes mellitus. It has critical functions in inflammatory cell migration, adhesion, and proliferation. Methods: 20 stage III/grade B periodontitis (P) and 20 healthy individuals (control; C) were included in this clinical study (all never smokers and systemically healthy). Clinical periodontal parameters were measured. Serum and GCF levels of CX3CL1, CX3CR1, and IL‐1β were quantified by enzyme‐linked immunosorbent assay and reported as total amounts and concentration. Results: The GCF concentrations and also total amount of CX3CL1, CX3CR1, and IL‐1β were statistically significantly higher in the patients with periodontitis compared with control group (P < 0.05). CX3CL1, CX3CR1, and IL‐1β levels in the GCF were significantly and positively correlated with all the clinical periodontal parameters (PI, PPD, BOP, and CAL; P < 0.01, P < 0.05). There was a significant correlation between IL‐1β, CX3CL1, and CX3CR1 concentrations in the GCF (respectively; r = 0.838 and r = 0.874, P < 0.01). Conclusion: Fractalkine and its receptor may play role in mechanisms through the regulation of inflammation or on the pathogenesis of periodontal disease. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the influence of systemic zoledronate administration on the osseointegration of titanium implants with different surface topography in rat maxillae. Methods: Twenty Sprague‐Dawley rats were divided into two groups—test (bisphosphonate) and control (healthy). Bisphosphonate administration began three weeks prior to implant placement, and the animals received zoledronate (66 μg/kg) three times per week. Forty endosseous implants with a moderately rough (20 implants) or a turned surface (20 implants) were immediately placed bilaterally into extraction sockets of maxillary first molars. Animals were sacrificed after 14 and 28 days of healing, and en bloc specimens were harvested for histological and histomorphometric analysis. Osseointegration was quantified by measuring the percentage of bone‐to‐implant contact. Results: Bone‐to‐implant contact (BIC) (mean ± SD) values of moderately rough and turned implants at day 14 in test group were 17.62 ± 6.68 and 10.69 ± 1.48, respectively, while in the control group, they were 46.36 ± 5.08 and 33.29 ± 8.89, respectively. At day 28, BIC values of moderately rough and turned implants in the test group were 25.94 ± 7.87 and 7.83 ± 4.30, respectively, while in the control group, they were 72.99 ± 6.60 and 47.62 ± 18.19, respectively. Statistically significant higher BIC values were measured on moderately rough implants compared to turned implants at 28 days, and the control group compared to the test group for both implant surfaces. Histological observations for the control and the test groups demonstrated initial bone formation around moderately rough implants not only on the surface of the parent bone, as was the case with the turned surfaced implants, but also along the implant surface itself. Conclusions: Systemic zoledronate administration negatively influences osseointegration. Osseointegration was enhanced adjacent to moderately rough compared to turned implants in both the presence and absence of systemic zoledronate administration. Therefore, topographical surface modification may partially offset the negative impact of zoledronate administration. [ABSTRACT FROM AUTHOR]

The present systematic review and meta‐analysis was carried out to determine the extent to which supracrestal tissue attachment (STA) thickness affects marginal bone loss (MBL) around dental implants. An electronic search was conducted in PubMed (MEDLINE), EMBASE, and complementary sources covering the period up to June 2018. The studies were meta‐analyzed based on implant position with respect to the alveolar bone crest (crestal/supracrestal). The MBL values were categorized according to STA width (thick/thin). Of the 1062 eligible titles, nine articles were included in the review. The implants were positioned crestal or supracrestal with respect to the alveolar ridge. The difference between (thin/thick) STA was statistically significant among analytical subsets in terms of lesser MBL (crestal‐positioned: weighted mean difference [WMD] = 0.52, 95% CI [0.03‐1.01]; P = 0.036; supracrestal‐positioned: WMD = 1.26; 95% CI [1.12‐1.39]; P = 0.00; pooled analysis: WMD = 0.73; 95% CI [0.033‐1.13]; P < 0.01). Implant positioning and patient age showed statistical significance in the meta‐regression analysis. The heterogeneity explained by age was R2 = 39.8%. Despite its limitations, the present study demonstrates that implants with thin STA result in greater MBL. There is moderate certainty of the evidence for a large effect of MBL prevention "in favor" of a thick STA environment in crestal‐positioned implants and the pooled analysis, but lesser certainty when only supracrestal‐positioned implants are considered. No trials studying this topic in subcrestal‐positioned implants were found. [ABSTRACT FROM AUTHOR]

Lekovic V, Milinkovic I, Aleksic Z, Jankovic S, Stankovic P, Kenney EB, Camargo PM. Platelet-rich fibrin and bovine porous bone mineral vs. platelet-rich fibrin in the treatment of intrabony periodontal defects. J Periodont Res 2012; 47: 409-417. © 2011 John Wiley & Sons A/S Background and Objective: Bovine porous bone mineral (BPBM) is a xenograft that has been successfully utilized in periodontal regeneration. Platelet-rich fibrin (PRF) is a leukocyte and platelet preparation that concentrates various polypeptide growth factors and therefore has the potential to be used as regenerative treatment for periodontal defects. The purpose of this study was to examine the suitability of autologous PRF as regenerative treatment for periodontal intrabony defects in humans and to examine the ability of BPBM to augment the regenerative effects exerted by PRF. Material and Methods: Using a split-mouth design, 17 paired intrabony defects were randomly treated either with PRF or with PRF-BPBM combination. Re-entry surgeries were performed at 6 mo. Primary study outcomes were changes in pocket depth, attachment level and defect fill. Results: Preoperative pocket depths, attachment levels and transoperative bone measurements were similar for the PRF and PRF-BPBM groups. Postsurgical measurements revealed a significantly greater reduction in pocket depth in the PRF-BPBM group (4.47 ± 0.78 mm on buccal and 4.29 ± 0.82 mm on lingual sites) when compared with the PRF group (3.35 ± 0.68 mm on buccal and 3.24 ± 0.73 mm on lingual sites). The PRF-BPBM group presented with significantly greater attachment gain (3.82 ± 0.78 mm on buccal and 3.71 ± 0.75 mm on lingual sites) than the PRF group (2.24 ± 0.73 mm on buccal and 2.12 ± 0.68 mm on lingual sites). Defect fill was also greater in the PRF-BPBM group (4.06 ± 0.87 mm on buccal and 3.94 ± 0.73 mm on lingual sites) than in the PRF group (2.21 ± 0.68 mm on buccal and 2.06 ± 0.64 mm on lingual sites). Conclusion: The results of this study indicate that PRF can improve clinical parameters associated with human intrabony periodontal defects, and BPBM has the ability to augment the effects of PRF in reducing pocket depth, improving clinical attachment levels and promoting defect fill. [ABSTRACT FROM AUTHOR]

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; 47: 446-454. © 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; Pam3CSK4 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. [ABSTRACT FROM AUTHOR]

Kim Y-T, Park J-C, Choi S-H, Cho K-S, Im G-I, Kim B-S, Kim C-S. The dynamic healing profile of human periodontal ligament stem cells: histological and immunohistochemical analysis using an ectopic transplantation model. J Periodont Res 2012; 47: 514-524. © 2012 John Wiley & Sons A/S Background and Objective: Human periodontal ligament stem cells (hPDLSCs) have been reported to play the pivotal role in periodontal regeneration. However, the dynamic cellular healing process initiated by hPDLSCs still remains to be elucidated. In the present study, the sequence of regeneration by hPDLSCs was assessed using histological and immunohistochemical observation in an ectopic transplantation model, which is a well-standardized assessment tool that excludes the innate healing factors from the animals. Material and Methods: Human periodontal ligament stem cells that were isolated and characterized from teeth ( n = 12) extracted for the purpose of orthodontic treatment were transplanted with carriers into ectopic subcutaneous pouches in immunocompromised mice ( n = 20). Animals were killed after several different healing periods: 3 d ( n = 4), 1 ( n = 4), 2 ( n = 4), 4 ( n = 4) and 8 wk ( n = 4). Histological analysis for regenerated tissues formed by hPDLSCs was conducted using hematoxylin and eosin, Masson's trichrome and picrosirius red staining. In addition, immunohistochemical staining was performed to observe the sequential expression of osteogenic/cementogenic and periodontal ligament tissue-specific markers associated with periodontal regeneration. Results: The whole healing process by transplanted hPDLSCs could be broadly divided into four distinctive phases. In the first phase, proliferated hPDLSCs migrated evenly all over the carrier, and collagenous tissues appeared in the form of amorphous collagen matrices. In the second phase, collagen fibers were well arranged among the carriers, and cementoid-like tissues were observed. In the third phase, the formation of mature collagen fibers, resembling Sharpey's fibers, was associated with active mineralization of cementum-like tissues, and in the fourth phase, the maturation of cementum-like tissues was observed on carrier surfaces. Various osteogenic/cementogenic markers related to the regeneration processes were expressed in a well-orchestrated time order. Interestingly, well-organized cementum-like and periodontal ligament fiber-like tissues and cells with early and late osteogenic/cementogenic markers were frequently observed in the secluded area of carrier surfaces. We termed this area the cell-rich zone. Conclusion: The results from this study clearly demonstrated the sequential histological changes during periodontal tissue regeneration by hPDLSCs. Understanding of this process would potentially enable us to develop better cell-based treatment techniques. [ABSTRACT FROM AUTHOR]

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 2012; 47: 479-487. © 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. [ABSTRACT FROM AUTHOR]

Brito F, Almeida S, Figueredo CMS, Bregman R, Suassuna JHR, Fischer RG. Extent and severity of chronic periodontitis in chronic kidney disease patients. J Periodont Res 2012; 47: 426-430. © 2011 John Wiley & Sons A/S Background and Objectve: Chronic inflammatory diseases have been investigated as a possible source of inflammation in chronic kidney disease patients; however, there is a shortage of information about the prevalence of periodontitis in such individuals. Therefore, the aim of this cross-sectional study was to determine the extent and severity of periodontitis in chronic kidney disease patients undergoing the following three different treatment modalities: predialysis; continuous ambulatory peritoneal dialysis (CAPD); and hemodialysis (HD); and to compare the findings with those from systemically healthy individuals. Material and Methods: Forty CAPD patients (mean age 52 ± 12 years), 40 HD patients (mean age 50 ± 10 years), 51 predialysis patients (mean age 54 ± 11 years) and 67 healthy individuals (mean age 50 ± 7 years) were examined. The periodontal examination included probing pocket depth, clinical attachment loss, bleeding on probing and presence of plaque. Patients with at least four sites with clinical attachment loss ≥ 6 mm were considered to have severe chronic periodontitis, and those with at least 30% of sites with clinical attachment loss ≥ 4 mm were considered to have generalized chronic periodontitis. Results: Predialysis and HD patients had significantly more sites with clinical attachment loss ≥ 6 mm than healthy individuals. The CAPD patients had similar periodontal condition to healthy subjects. There were significantly more cases of severe chronic periodontitis in predialysis and HD patients. Conclusion: Predialysis and HD are associated with a higher prevalence of severe periodontitis compared with healthy individuals and CAPD patients. [ABSTRACT FROM AUTHOR]

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; 47: 470-478. © 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. [ABSTRACT FROM AUTHOR]

Kuo PJ, Tu HP, Chin YT, Lu SH, Chiang CY, Chen RY, Fu E. Cyclosporine-A inhibits MMP-2 and -9 activities in the presence of Porphyromonas gingivalis lipopolysaccharide: an experiment in human gingival fibroblast and U937 macrophage co-culture. J Periodont Res 2012; 47: 431-438. © 2012 John Wiley & Sons A/S Background and Objective: Studies have shown that bacterial plaque and the associated gingival inflammation increase the severity of gingival overgrowth induced by cyclosporine-A (CsA). This in vitro study aimed to evaluate the effect of CsA on the activities of MMPs from the co-culture of human gingival fibroblasts and U937 macrophages in the presence or absence of Porphyromonas gingivalis lipopolysaccharide (LPS). Material and Methods: Activities of pro-MMP-2, MMP-2 and pro-MMP-9 in the supernatants of independent cultures and co-cultures were examined by zymography. RT-PCR was selected to evaluate the expression of mRNA for membrane type-1 (MT1) MMP in the co-cultures. Results: Activities of MMPs in the co-cultures were significantly greater when compared with any of the independent cultures. Lipopolysaccharide significantly increased the MMP activities in a dose-dependent manner in the co-cultures, whereas CsA inhibited these activities. In the presence of both CsA and LPS, the MMP activities inhibited by CsA could still be observed in the co-cultures. In the individual cultures, in contrast, the CsA-inhibited MMP activities, in the presence of LPS, were minimally detected. The mRNA expression of MT1-MMP was significantly enhanced after LPS treatment; however, this enhancement was inhibited by CsA. Conclusion: This study demonstrated that, in co-cultures of human gingival fibroblasts and U937 macrophages, CsA could inhibit MMP activities in the presence of P. gingivalis LPS. It might be part of the underlying reason for the persistent overgrowth of gingiva seen when bacterial plaque and local inflammation are present during CsA therapy. [ABSTRACT FROM AUTHOR]

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; 47: 500-507. © 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. [ABSTRACT FROM AUTHOR]

Aoyama N, Suzuki J-I, Ogawa M, Watanabe R, Kobayashi N, Hanatani T, Yoshida A, Ashigaki N, Izumi Y, Isobe M. Clarithromycin suppresses the periodontal bacteria-accelerated abdominal aortic aneurysms in mice. J Periodont Res 2012; 47: 463-469. © 2011 John Wiley & Sons A/S Background and Objective: Although clarithromycin (CAM) has many biological functions, including regulation of MMPs, little is known about its effect on abdominal aortic aneurysms. Periodontopathic bacteria have been reported to be associated with several kinds of circulatory diseases. The purpose of this study was therefore to clarify the effect of CAM on periodontopathic bacteria-accelerated abdominal aortic aneurysms. Material and Methods: Abdominal aortic aneurysm was produced in mice by the peri-aortic application of 0.25 m CaCl2. The mice were inoculated once per week with live Porphyromonas gingivalis, which is one of the major periodontopathic bacteria. Test mice ( n = 8) were given a daily oral dose of CAM, while control mice ( n = 13) were not. Results: Four weeks after the operation, the P. gingivalis-injected and CAM-treated mice showed a significant decrease in the aortic diameter in comparison with the mice only injected with P. gingivalis. Histopathologically, the samples obtained from the P. gingivalis-injected and CAM-treated mice showed less elastic degradation. Moreover, the plasma MMP-2 concentration of the CAM-treated mice decreased significantly. Conclusion: These findings suggest that CAM administration is useful to suppress periodontal bacteria-accelerated abdominal aortic aneurysms via MMP regulation. [ABSTRACT FROM AUTHOR]

Zini A, Sgan-Cohen H D, Marcenes W. Is religiosity related to periodontal health among the adult Jewish population in Jerusalem? J Periodont Res 2012; 47: 418-425. © 2011 John Wiley & Sons A/S Background and Objective: Religiosity may be a relevant protective factor for periodontitis, as it is for other chronic systemic diseases. The objective of the present study was to assess the relationship between periodontitis and religiosity, and whether oral health-related behaviours, spirituality and social support are included in the potential pathways that explain the association between religiosity and periodontitis. Material and Methods: Cross-sectional data were part of a retrospective study. The stratified random-sampling technique was limited to the Jerusalem Jewish population. Conceptual hierarchical data analysis modelling was adopted, assuming that socio-economic position was the most distal determinant, age and gender were confounders, and social support, spirituality and oral health behaviours were mediators in the relationship between religiosity and periodontitis. Results: Kappa intra-examiner values (0.89) were satisfactory. Response rate was 88.0%. The final sample included 123 men and 125 women. The mean age was 38.6 years (SD 3.25 years), with 33.9% declared to be 'orthodox', 33.1%'religious' and 33.1%'secular'. Higher levels of religiosity ( p = 0.01), support of internal life through spirituality ( p = 0.03), higher family social support ( p = 0.02) and low levels of plaque ( p = 0.05) were related to lower levels of periodontitis. Religiosity led to higher family social support and support of internal life through spirituality, which was related to plaque level and periodontitis. Conclusion: Religiosity had a protective effect against periodontitis through extrinsic and intrinsic pathways. This should be considered as part of aetiology and prognosis, in potential prevention and care of periodontitis. [ABSTRACT FROM AUTHOR]

Adibrad M, Deyhimi P, Ganjalikhani Hakemi M, Behfarnia P, Shahabuei M, Rafiee L. Signs of the presence of Th17 cells in chronic periodontal disease. J Periodont Res 2012; 47: 525-531. © 2012 John Wiley & Sons A/S Background and Objective: The aim of this study was to identify the specific markers of T helper 17 (Th17) cells and their variations in people suffering from chronic periodontal disease in comparison with normal control subjects. Material and Methods: In 30 patients with periodontitis and 30 normal control subjects, the mRNA expressions of interleukin (IL)-17A and retinoic orphan receptor C2 (RORC2) were measured by quantitative RT-PCR. The protein levels of IL-17A and RORC2 were also evaluated by immunohistochemistry. The levels of these markers were compared between healthy and diseased periodontal tissues by the Mann-Whitney U-test. Results: In periodontal lesions, IL-17A and RORC2 were significantly overexpressed compared with normal tissues. According to our immunohistochemical analysis, the number of IL-17A-positive cells and RORC2-positive cells was significantly greater in periodontal lesions compared with control sites. Moreover, there was a positive correlation between the presence of IL-17A and RORC2 transcript and protein content levels in the gingiva of diseased patients. Conclusion: The results demonstrated a significant increase in the number of some specific markers of Th17 cells in patients suffering from periodontal disease in comparison with normal control subjects. [ABSTRACT FROM AUTHOR]

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; 47: 455-462. © 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. [ABSTRACT FROM AUTHOR]

Thomasini RL, Bonon SH, Durante P, Costa SCB. Correlation of cytomegalovirus and human herpesvirus 7 with CD3 + and CD3 + CD4 + cells in chronic periodontitis patients. J Periodont Res 2012; 47: 114-120. © 2011 John Wiley & Sons A/S Background and Objective: Human chronic periodontitis is an inflammatory process characterized by dense accumulation of immune cells in the periodontal tissue. The periodontitis can lead to loss of teeth in the patient and the pathogenesis of this disease is not completely known. This study tested the hypothesis that chronic periodontitis-affected sites can harbor betaherpesviruses and that viruses are linked to a profile of the inflammatory infiltrate. Material and Methods: Biopsies of periodontal tissue were taken from periodontitis-affected patients and from healthy subjects. Immunohistochemistry was performed to count CD19+ B cells, CD3+ total T cells, T-CD4+ and T-CD8+ cell subsets, and PCR was performed to detect cytomegalovirus and human herpesvirus 6 and 7 in the samples. One slide of each sample was stained with Giemsa for histopathological examination and to evaluate the quality of the cellular infiltrate. Results: As expected, tissues collected from healthy subjects presented no significant level of inflammatory infiltration and were therefore excluded from immunostaining procedures. Results showed that CD19+ B cells were in higher number than CD3+ T cells in the periodontitis-affected tissue, but this was not statistically significant. The T-CD4+ lymphocyte subset was significantly higher than the T-CD8+ lymphocyte subset ( p = 0.004) in the samples. Cytomegalovirus and human herpesvirus 7 were found at periodontitis-affected sites, but not in tissue collected from healthy subjects ( p = 0.04 and p = 0.04, respectively). Human herpesvirus 6 was rarely detected. We found a correlation between cytomegalovirus and lower CD19+/CD3+ ratios (ratio < 0.9, p = 0.003) and between human herpesvirus 7 and lower CD19+/CD3+ ratios (ratio < 0.9, p = 0.003) and higher CD4+/CD8+ ratios (ratio > 1.1, p = 0.002). Conclusion: This study shows that cytomegalovirus and human herpesvirus 7 can be present at periodontitis-affected sites but are uncommon at healthy periodontal sites. Moreover, our data suggest that cytomegalovirus can be related to an inflammatory infiltrate with predominance of CD3+ T cells, whereas human herpesvirus 7 can be associated with an infiltrate with predominance of T-CD4+ cells. However, further studies are necessary to support this hypothesis. Herpesviruses could play a role in human chronic periodontitis by modulation of the T cell response. [ABSTRACT FROM AUTHOR]

Ozdemir H, Kara MI, Erciyas K, Ozer H, Ay S. Preventive effects of thymoquinone in a rat periodontitis model: a morphometric and histopathological study. J Periodont Res 2012; 47: 74-80. © 2011 John Wiley & Sons A/S Background and Objective: Thymoquinone has a variety of pharmacologic properties, including antihistaminic, antibacterial, antihypertensive, hypoglycemic, anti-inflammatory and anti-oxidative activities. Through its anti-inflammatory and antioxidant properties, thymoquinone may play an important role in preventing periodontal diseases. The aim of this study was to evaluate the effectiveness of thymoquinone in preventing the initiation and progression of periodontitis in a rat periodontitis model. Material and Methods: Twenty-four rats were randomly divided into three experimental groups: a nonligated (NL) treatment group ( n = 8), a ligature-only (LO) treatment group ( n = 8) and a ligature plus thymoquinone (10 mg/kg, daily for 11 d) (TQ) treatment group. In order to induce experimental periodontitis, a 4/0 silk suture was placed at the gingival margin of the right-mandibular first molars of the rats. Thymoquinone was administered by gastric feeding until the animals were killed on day 11. Changes in the alveolar bone levels of rats in each group were measured clinically, and tissues of rats in each group were examined histopathologically to determine inflammatory cell infiltration (ICI), osteoblast and osteoclast activities, and osteoclast morphology. Results: Alveolar bone loss around the mandibular molar tooth was significantly higher in the LO group compared with NL and TQ groups ( p < 0.05). The ratio of the presence of ICI and osteoclast numbers was significantly higher in the LO group than in the NL and TQ groups ( p < 0.05). Osteoblastic activity was significantly lower in the LO group than in the NL and TQ groups ( p < 0.05). Conclusion: The present study showed that the oral administration of thymoquinone diminishes alveolar bone resorption in a rat periodontitis model. [ABSTRACT FROM AUTHOR]

Sugita N, Iwanaga R, Kobayashi T, Yoshie H. Association of the FcγRIIB-nt645+25A/G polymorphism with the expression level of the FcγRIIb receptor, the antibody response to Porphyromonas gingivalis and the severity of periodontitis. J Periodont Res 2012; 47: 105-113. © 2011 John Wiley & Sons A/S Background and Objective: Human FcγRIIb is an immunoglobulin G (IgG) receptor that inhibits the activation of B lymphocytes through cross-linking with the B-cell receptor via immune complexes. This function acts as a negative regulator of antibody production. Our previous studies have demonstrated the gene polymorphisms in FcγRIIb to be associated with periodontitis. In this study, we presented a polymorphism - FcγRIIB-nt645+25A/G (rs2125685) - in intron 4 and analyzed its functional relevance to periodontitis. We examined whether the FcγRIIB-nt645+25A/G polymorphism is associated with periodontal parameters, the IgG response to the periodontopathic bacterium Porphyromonas gingivalis and/or the expression level of FcγRIIb on peripheral B lymphocytes. Material and Methods: Thirty-two patients with chronic periodontitis were genotyped with nested PCR and by direct sequencing of genome DNA. The levels of serum IgG and of specific IgG subclasses for P. gingivalis sonicate and for the recombinant 40-kDa outer membrane protein (OMP) were determined. The expression levels of FcγRIIb on peripheral B lymphocytes from 19 healthy donors were measured by flow cytometry. Results: Patients with the FcγRIIB-nt645+25AA genotype showed significantly higher mean clinical attachment levels compared to patients with the Fcγ RIIB-nt645+25GG genotype ( p = 0.003) and a significantly lower IgG response to P. gingivalis sonicate and to the 40-kDa OMP. The expression levels of FcγRIIb protein on the cell surface in peripheral B lymphocytes were higher in healthy donors with the FcγRIIB-nt645+25AA genotype than in those with the FcγRIIB-nt645+25GG genotype ( p = 0.03). Conclusion: The higher expression levels of FcγRIIb in subjects with the FcγRIIB-nt645+25AA genotype may induce a lower level of production of IgG against P. gingivalis and therefore more severe periodontitis. [ABSTRACT FROM AUTHOR]

Kraft-Neumärker M, Lorenz K, Koch R, Hoffmann T, Mäntylä P, Sorsa T, Netuschil L. Full-mouth profile of active MMP-8 in periodontitis patients. J Periodont Res 2012; 47: 121-128. © 2011 John Wiley & Sons A/S Background and Objective: MMP-8 in gingival crevicular fluid is considered as a protease with high destructive potential because of its ability to degrade collagen in periodontitis-affected patients. The aim of this study was to investigate whether there was a relationship between clinical diagnostic parameters and the concentration of active MMP-8 (aMMP-8) in gingival crevicular fluid in a site-level full-mouth analysis. Based on these data, the prognostic value of aMMP-8 levels in relation to pocket depth may be evaluated. Material and Methods: Clinical measurements of pocket depth, bleeding on probing (BOP), plaque index (PlI) and gingival index (GI), as well as samples of gingival crevicular fluid, were obtained from four sites of each tooth of nine healthy female patients with chronic generalized periodontitis. The aMMP-8 concentration in gingival crevicular fluid was quantified by ELISA using specific monoclonal antibodies. Multiple linear regression models for the single measures of aMMP-8 and pocket depth were calculated with GI and BOP as additional variables. Results: Between 92 and 112 recordings were obtained for each parameter in each patient. Mean values of between 31.5 and 88.8% were calculated for pocket depths of ≥ 4 mm. Mean pocket depths ranged from 3.11 to 4.73 mm, the mean BOP values ranged from 34.0 to 96.7% and the mean full-mouth gingival crevicular fluid aMMP-8 concentration ranged from 3.2 to 23.7 ng/mL. Conclusion: In this sample of female periodontitis patients, a broad range of intra-individual and interindividual aMMP-8 values was found. Although the explained variance was rather weak, a statistically significant relationship between aMMP-8 and pocket depth was proven. [ABSTRACT FROM AUTHOR]

Fujita T, Yumoto H, Shiba H, Ouhara K, Miyagawa T, Nagahara T, Matsuda S, Kawaguchi H, Matsuo T, Murakami S, Kurihara H. Irsogladine maleate regulates epithelial barrier function in tumor necrosis factor-α -stimulated human gingival epithelial cells. J Periodont Res 2012; 47: 55-61. © 2011 John Wiley & Sons A/S Background and Objective: As epithelial cells function as a mechanical barrier, the permeability of the gingival epithelial cell layer indicates a defensive capability against invasion by periodontal pathogens. We have reported the expression of claudin-1 and E-cadherin, key regulators of permeability, in the gingival junctional epithelium. Irsogladine maleate (IM) is a medication for gastric ulcers and also regulates Aggregatibacter actinomycetemcomitans-stimuated chemokine secretion and E-cadherin expression in gingival epithelium. In this study, we have further investigated the effects of IM on the barrier functions of gingival epithelial cells under inflammatory conditions. Material and methods: We examined the permeability, and the expression of claudin-1 and E-cadherin, in human gingival epithelial cells (HGECs) stimulated with tumor necrosis factor (TNF)-α, with or without IM. Results: TNF-α increased the permeability of HGECs, and IM abolished the increase. TNF-α reduced the expression of E-cadherin in HGECs, and IM reversed the reduction. In addition, immunofluorescence staining showed that TNF-α disrupted claudin-1 expression in HGECs, and IM reversed this effect. Conclusion: The results suggest that IM reverses the TNF-α-induced disruption of the gingival epithelial barrier by regulating E-cadherin and claudin-1. [ABSTRACT FROM AUTHOR]

Rojo-Botello NR, García-Hernández AL, Moreno-Fierros L. Expression of toll-like receptors 2, 4 and 9 is increased in gingival tissue from patients with type 2 diabetes and chronic periodontitis. J Periodont Res 2012; 47: 62-73. © 2011 John Wiley & Sons A/S Background and Objective: Broad evidence indicates that diabetes both increases the risk and hastens the progression of periodontal disease. Likewise, chronic inflammation or infections seem to provoke insulin resistance and thereby contribute to the development of diabetes and its complications. Innate immune responses, which appear to be altered in individuals with diabetes, are usually mediated by the recognition of pathogens through toll-like receptors (TLRs). The constitutive expression of some TLRs has been reported in healthy human gingival tissue. Interestingly, the expression of TLRs 2 and 4 is increased with the severity of periodontal disease. Considering that the inflammatory reaction is exacerbated in individuals with diabetes and periodontitis, we suspected that the expression of some TLRs might be increased in gingival tissue in these patients. Material and Methods: In this study, we analyzed, by immunofluorescence, the expression of TLRs 2, 3, 4 and 9 in gingival tissues from healthy individuals and from periodontal patients with or without type 2 diabetes. Results: We found that the expression levels of TLRs 2, 3, 4 and 9 were higher in all periodontal patients than in healthy individuals. The expression of some TLRs was increased in subjects with periodontitis and diabetes relative to subjects with periodontitis but without diabetes; this increase in expression was found particularly in TLR2 and TLR9 in the connective tissue and in TLR4 at the epithelial region. Conclusion: These data suggest that the expression of these TLRs 2, 3, 4 and 9 in gingival tissue is higher in individuals with diabetes because its inflammatory reaction is exacerbated. Additionally, the expression of these TLRS is positively regulated with the severity of periodontal disease. [ABSTRACT FROM AUTHOR]

Takano M, Sugano N, Mochizuki S, Koshi RN, Narukawa TS, Sawamoto Y, Ito K. Hepatocytes produce tumor necrosis factor-α and interleukin-6 in response to Porphyromonas gingivalis. J Periodont Res; 2012; 47: 89-94. © 2011 John Wiley & Sons A/S Background and Objective: The liver plays a major role in clearing systemic bacterial infections. In addition, inflammatory cytokines produced in the liver play a critical role in systemic cytokine levels. The aim of this study was to investigate the production of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) by hepatocytes in response to periodontal pathogens. Material and Methods: The mouse hepatic carcinoma cell line Hepa-1.6 and the mouse macrophage-like cell line RAW 264 were co-cultured in Transwell insert plates. Cells were stimulated with bacterial extracts prepared from Porphyromonas gingivalis and the induction of TNF-α and IL-6 was measured using real-time PCR and ELISA. Results: After stimulation with bacteria, the induction of TNF-α and IL-6 was observed in RAW 264 cells and Hepa-1.6 cells. Significant reduction of TNF-α mRNA expression in Hepa-1.6 cells was observed after treatment with antibody to TNF-α. Conclusion: The results obtained in the present study show that P. gingivalis extract induces TNF-α and IL-6 in an in vitro liver model and that macrophage-derived TNF-α mediates the induction of TNF-α in hepatocytes. [ABSTRACT FROM AUTHOR]

Santos VR, Ribeiro FV, Lima JA, Miranda TS, Feres M, Bastos MF, Duarte PM. Partial- and full-mouth scaling and root planing in type 2 diabetic subjects: a 12-mo follow-up of clinical parameters and levels of cytokines and osteoclastogenesis-related factors. J Periodont Res 2012; 47: 45-54. © 2011 John Wiley & Sons A/S Background and Objective: The aim of this study was to evaluate the effects of full-mouth scaling and root planing (FMSRP) and partial-mouth scaling and root planing (PMSRP), up to 12 mo after treatment, on clinical parameters, and levels of cytokines and osteoclastogenesis-related factors in type 2 diabetic subjects with chronic periodontitis. Material and Methods: Thirty-four subjects received FMSRP ( n = 17) or PMSRP ( n = 17) within 24 h or in multiple sessions, respectively. Clinical parameters and local levels of tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin (IL)-17, IL-23, IL-4, receptor activator of NF-β ligand and osteoprotegerin were assessed at baseline, and 3, 6 and 12 mo after therapies. Results: Clinical parameters improved after both therapies ( p < 0.05), and no between-group differences were observed at any time-point ( p > 0.05). Overall, there were no considerable differences in the local levels of the biomarkers studied between groups ( p > 0.05). The IL-23 concentration and total amount of IFN-γ increased in the FMSRP group and decreased in the PMSRP group from baseline to 3 mo and from baseline to 6 mo, respectively ( p < 0.05). Conclusion: Both PMSRP and FMSRP promoted benefits in clinical parameters and showed a similar modulation of cytokines and osteoclastogenesis-related factors at 12 mo in type 2 diabetic subjects. [ABSTRACT FROM AUTHOR]

Park J-C, So S-S, Jung I-H, Yun J-H, Choi S-H, Cho K-S, Kim C-S. Induction of bone formation by Escherichia coli -expressed recombinant human bone morphogenetic protein-2 using block-type macroporous biphasic calcium phosphate in orthotopic and ectopic rat models. J Periodont Res 2011; 46: 682-690. © 2011 John Wiley & Sons A/S Background and Objective: The potential of the Escherichia coli-expressed recombinant human bone morphogenetic protein-2 (ErhBMP-2) to support new bone formation/maturation using a block-type of macroporous biphasic calcium phosphate (bMBCP) carrier was evaluated in an orthotopic and ectopic rat model. Material and Methods: Critical-size (Φ 8 mm) calvarial defects and subcutaneous pockets in 32 Sprague-Dawley rats received implants of rhBMP-2 (2.5 μg) in a bMBCP carrier or bMBCP alone (control). Implant sites were evaluated using histological and histometric analysis following 2- and 8-wk healing intervals (eight animals/group/interval). Results: ErhBMP-2/bMBCP supported significantly greater bone formation at 2 and 8 wk (10.8% and 25.4%, respectively) than the control at 2 and 8 wk (5.3% and 14.0%, respectively) in calvarial defects ( p < 0.01). Bone formation was only observed for the ErhBMP-2/bMBCP ectopic sites and was significantly greater at 8 wk (7.5%) than at 2 wk (4.5%) ( p < 0.01). Appositional and endochondral bone formation was usually associated with a significant increase in fatty marrow at 8 wk. The bMBCP carrier showed no evidence of bioresorption. Conclusion: ErhBMP-2/bMBCP induced significant bone formation in both calvarial and ectopic sites. Further study appears to be required to evaluate the relevance of the bMBCP carrier. [ABSTRACT FROM AUTHOR]

Lee Y-M, Shin S-I, Shin K-S, Lee Y-R, Park B-H, Kim E-C. The role of sirtuin 1 in osteoblastic differentiation in human periodontal ligament cells. J Periodont Res 2011; 46: 712-721. © 2011 John Wiley & Sons A/S Background and Objective: Activation of sirtuin 1 (SIRT1) promotes the differentiation of keratinocytes and mesenchymal stem cells, but inhibits the differentiation of muscle and fat cells. However, the involvement of SIRT1 in the differentiation of human periodontal ligament cells into osteoblast-like cells remains unclear. To identify the role of SIRT1 in human periodontal ligament cells, we measured SIRT1 mRNA and SIRT1 protein levels during the osteoblastic differentiation of human periodontal ligament cells. Additionally, we investigated the effects of overexpressing and underexpressing SIRT1 on the differentiation of human periodontal ligament cells, and the signaling mechanisms involved. Material and Methods: Expression of SIRT1 and osteoblastic differentiation markers was assessed by RT-PCR, real-time PCR, Alizarin red staining and western blotting. Results: Marked upregulation of SIRT1 mRNA and SIRT1 protein was observed in cells grown for 3 d in osteogenic induction medium (OM). Activation of SIRT1 using resveratrol and isonicotinamide stimulated osteoblastic differentiation in a dose-dependent manner, as assessed by the expression of mRNAs encoding alkaline phosphatase, osteopontin, osteocalcin, osterix and Runx2, and induced calcium deposition. In contrast, inhibition of SIRT1 using sirtinol, nicotinamide and gene silencing by RNA interference suppressed mineralization and the expression of osteoblast marker mRNAs. Further mechanistic studies revealed that resveratrol treatment increased the phosphorylation of Akt, adenosine monophosphate kinase (AMPK), Smad 1/5/8 and c-Jun N-terminal kinase, but reduced OM-induced activation of nuclear factor-κB. Conversely, application of sirtinol suppressed the phosphorylation of Akt, AMPK, Smad 1/5/8, p38, ERK and c-Jun N-terminal kinase, and enhanced nuclear factor-κB activity, in OM-stimulated cells. Conclusion: These data suggest that SIRT1 is a potent regulator of differentiation of human periodontal ligament cells and may have clinical implications for periodontal bone regeneration. [ABSTRACT FROM AUTHOR]

Breivik T, Gundersen Y, Gjermo P, Taylor SM, Woodruff TM, Opstad PK. Oral treatment with complement factor C5a receptor (CD88) antagonists inhibits experimental periodontitis in rats. J Periodont Res 2011; 46: 643-647. © 2011 John Wiley & Sons A/S Background and Objective: The complement activation product 5a (C5a) is a potent mediator of the innate immune response to infection, and may thus also importantly determine the development of periodontitis. The present study was designed to explore the effect of several novel, potent and orally active C5a receptor (CD88) antagonists (C5aRAs) on the development of ligature-induced periodontitis in an animal model. Material and Methods: Three different cyclic peptide C5aRAs, termed PMX205, PMX218 and PMX273, were investigated. Four groups of Wistar rats ( n = 10 in each group) were used. Starting 3 d before induction of experimental periodontitis, rats either received one of the C5aRas (1-2 mg/kg) in the drinking water or received drinking water only. Periodontitis was assessed when the ligatures had been in place for 14 d. Results: Compared with control rats, PMX205- and PMX218-treated rats had significantly reduced periodontal bone loss. Conclusion: The findings suggest that complement activation, and particularly C5a generation, may play a significant role in the development and progression of periodontitis. Blockade of the major C5a receptor, CD88, with specific inhibitors such as PMX205, may offer novel treatment options for periodontitis. [ABSTRACT FROM AUTHOR]

Alkan EA, Parlar A. EMD or subepithelial connective tissue graft for the treatment of single gingival recessions: a pilot study. J Periodont Res 2011; 46: 637-642. © 2011 John Wiley & Sons A/S Background and Objective: The combination of EMD with root-coverage procedures has been shown to promote periodontal regeneration on the exposed root surface. The aim of this randomized clinical study was to compare the efficacy of EMD with connective tissue graft (CTG) for the treatment of Miller Class I and Class II single recessions in a split-mouth design. Material and methods: The study included 12 systemically healthy patients, each with two single bilateral gingival recession defects (24 recessions). One recession defect in each patient was treated with the coronally advanced flap (CAF) + EMD procedure and the other recession defect was treated with the CTG + EMD procedure, in a split-mouth study design. The parameters recession depth (RD), recession width, percentage of root coverage, height of keratinized tissue (HKT), gingival thickness, probing depth and clinical attachment level (CAL) were recorded at baseline. All parameters, except for gingival thickness, were remeasured at 6 and 12 mo. Results: The mean percentage root coverage at the final evaluation was 92 ± 14% for the CAF + EMD group and 89 ± 14% for the CAF + CTG group. Both treatments resulted in statistically significant ( p < 0.05) decreases in RD and recession width, and increases in HKT, at 6 and 12 mo. There was also a significant decrease in the probing depth and a significant gain in the CAL for both groups. The probing depth was statistically higher in the CAF + CTG group than in the CAF + EMD group at 6 mo ( p < 0.05), while the CAL was statistically lower in the CAF + EMD group than in the CAF + CTG group at 6 and 12 mo ( p < 0.05). Conclusion: The present study demonstrated that both CAF + EMD and CAF + CTG procedures were similarly successful in treating Miller Class I and Class II single gingival recession defects. [ABSTRACT FROM AUTHOR]

Cantley MD, Bartold PM, Marino V, Fairlie DP, Le GT, Lucke AJ, Haynes DR. Histone deacetylase inhibitors and periodontal bone loss. J Periodont Res 2011; 46: 697-703. © 2011 John Wiley & Sons A/S Background and Objective: Bone loss caused by enhanced osteoclast activity is a significant feature of periodontitis. Histone deacetylase inhibitors (HDACi) can suppress osteoclast-mediated bone loss in vitro and in vivo. This study investigated whether HDACi can suppress bone loss in experimental periodontitis. Material and methods: Experimental periodontitis was induced in mice by oral inoculation with Porphyromonas gingivalis bacteria. Mice were treated orally with olive oil alone, with olive oil and a novel compound - 1179.4b - which targets both Class I and Class II histone deacetylases (HDACs) or with olive oil and MS-275, which targets Class I HDACs. Micro-computed tomography scans of live mice, stereo imaging and histological analyses were used to detect changes in bone. Results: In the absence of treatment there was a 13.2% increase in bone volume in controls compared with a 7.4% decrease in P. gingivalis-inoculated mice. 1179.4b significantly reduced bone loss, with a 3.4% increase in bone volume ( p < 0.01). MS-275 did not have a significant effect on P. gingivalis-induced bone loss. Histological analysis revealed that 1179.4b reduced bone loss despite having no effect on inflammation. Conclusion: HDACi were found to effectively suppress bone loss in the mouse model of periodontitis. 1179.4b - the inhibitor of Class I and Class II HDACs - was more effective at suppressing bone loss than MS-275, which targets Class I HDACs only. These compounds may therefore have the potential to be used for the management of periodontitis. [ABSTRACT FROM AUTHOR]

Xu C, Hao Y, Wei B, Ma J, Li J, Huang Q, Zhang F. Apoptotic gene expression by human periodontal ligament cells following cyclic stretch. J Periodont Res 2011; 46: 742-748. © 2011 John Wiley & Sons A/S Background and Objective: Periodontal ligament cells play an important role in maintaining homeostasis of periodontal tissue upon mechanical force loading caused by mastication or orthodontic force. Previous studies revealed force-driven periodontal ligament cell death via apoptosis, but the force-sensing genes assigned to the apoptotic pathway have not been fully characterized. The present study aimed to identify force-sensing genes implicated in the apoptotic pathway in periodontal ligament cells. Material and Methods: Human periodontal ligament cells were exposed to 20% stretch strain for 6 or 24 h, and the differential expression of 84 genes implicated in the apoptotic pathway were quantified by real-time PCR array technology. Results: Ten and 11 genes showed upregulated expression after 6 and 24 h stretches, respectively, and there were two downregulated genes in response to both 6 and 24 h stretches. These genes included those encoding the tumor necrosis factor ligand family ( TNFSF8), tumor necrosis factor receptor family ( FAS, TNFRSF10B, TNFRSF11B, TNFRSF25 and CD27), the Bcl-2 family ( BAG3, BAK1, BCL2L11 and BCLAF1), the caspase family ( CASP5 and CASP7), the inhibitor of apoptosis proteins family ( BIRC3, BIRC6 and NAIP), the caspase recruitment domain family ( RIPK2 and PYCARD) and the death domain family ( DAPK1), as well as an oncogene ( BRAF). Conclusion: This study identified several force-sensing genes implicated in the apoptotic pathway in periodontal ligament cells and should facilitate future studies on force-driven apoptosis by providing putative target genes. [ABSTRACT FROM AUTHOR]

Shibata Y, Okano S, Shiroza T, Tahara T, Nakazawa K, Kataoka S, Ishida I, Kobayashi T, Yoshie H, Abiko Y. Characterization of human-type monoclonal antibodies against reduced form of hemin binding protein 35 from Porphyromonas gingivalis . J Periodont Res 2011; 46: 673-681. © 2011 John Wiley & Sons A/S Background and Objective: The gram-negative anaerobe Porphyromonas gingivalis has been implicated as an important pathogen in the development of adult periodontitis, and its colonization of subgingival sites is critical in the pathogenic process. We previously identified a 35 kDa surface protein (hemin binding protein 35; HBP35) from P. gingivalis that exhibited coaggregation activity, while additional analysis suggested that this protein possessed an ability to bind heme molecules. For development of passive immunotherapy for periodontal diseases, human-type monoclonal antibodies have been prepared using HBP35 as an antigen in TransChromo mice. In the present study, we focused on a single antibody, TCmAb-h13, which is known to inhibit heme binding to recombinant HBP35. The aim of our investigation was to clarify the redox-related function of HBP35 and consider the benefits of human-type monoclonal antibodies. Material and Methods: To examine the antigen recognition capability of TCmAbs with immunoblotting and Biacore techniques, we used the native form as well as several Cys-to-Ser variants of recombinant HBP35. Results: We found that the redox state of recombinant HBP35 was dependent on two Cys residues, 48C and 51C, in the thioredoxin active center (WCGxCx). Furthermore, TCmAb-h13 recognized the reduced forms of recombinant HBP35, indicating its inhibitory effect on P. gingivalis growth. Conclusion: Hemin binding protein 35 appears to be an important molecule involved in recognition of the redox state of environmental conditions. In addition, TCmAb-h13 had an inhibitory effect on heme binding to recombinant HBP35, thereby interfering with P. gingivalis growth. [ABSTRACT FROM AUTHOR]

Pham TAV, Ueno M, Zaitsu T, Takehara S, Shinada K, Lam PH, Kawaguchi Y. Clinical trial of oral malodor treatment in patients with periodontal diseases. J Periodont Res 2011; 46: 722-729. © 2011 John Wiley & Sons A/S Background and Objective: Only a few clinical research studies have assessed different therapeutic approaches to oral malodor in subjects affected by periodontal diseases. The aim of this study was to evaluate the effects of periodontal treatment and tongue cleaning on oral malodor parameters in periodontitis and gingivitis patients. Material and Methods: The subjects were 102 periodontitis and 116 gingivitis patients with oral malodor. Oral malodor was measured by organoleptic test and Oral Chroma™. Oral health status, including tooth conditions, periodontal health, tongue coating and proteolytic activity of the BANA test in tongue coating were assessed. Subjects in each periodontal disease group were randomly assigned into two subgroups depending on the sequence of treatment: periodontal treatment and tongue cleaning. Oral malodor and oral health parameters were compared by groups and sequence of treatment. Results: For subjects in the periodontitis group, there were statistically significant reductions in oral malodor after periodontitis treatment or tongue cleaning; however, major reductions were found after periodontitis treatment. For those in the gingivitis group, there were also statistically significant reductions in oral malodor after gingivitis treatment or tongue cleaning, but the most marked reductions were observed after tongue cleaning. At the completion of treatment, all oral malodor parameters fell below the threshold levels in all subgroups. Conclusion: The present study indicated that periodontal treatment played an important role and tongue cleaning contributed to a lesser extent to reduction in oral malodor in periodontitis patients. In contrast, tongue cleaning alone can be the primary approach to reduce oral malodor in gingivitis patients. [ABSTRACT FROM AUTHOR]

Rego EB, Inubushi T, Miyauchi M, Kawazoe A, Tanaka E, Takata T, Tanne K. Ultrasound stimulation attenuates root resorption of rat replanted molars and impairs tumor necrosis factor-α signaling in vitro . J Periodont Res 2011; 46: 648-654. © 2011 John Wiley & Sons A/S. Background and Objective: A therapeutic protocol to minimize root resorption induced by tooth replantation has not yet been universally established. In this context, noninvasive modality such as ultrasound therapy have been a focus of increased interest. This study aimed to evaluate the inhibitory effect of ultrasound therapy on root resorption of replanted rat molars. In addition, the study aimed to promote insights into the mechanism through which ultrasound mediates the metabolism of periodontal cells in vitro. Material and Methods: An experimental model of tooth replantation in rats, involving luxation and immediate replacement of the maxillary first molars, was used to assess the inhibitory effect of an ultrasound-therapy regimen (15 min of exposure to ultrasound, each day for 21 d) on root resorption. Moreover, the effect of ultrasound on osteoclastogenesis/cementoclastogenesis was examined in vitro using a mouse osteoblastic stromal cell line (ST2) and a mouse cementoblastic cell line (OCCM-30). Results: The area of root resorption lacunae was statistically decreased ( p < 0.01) in the ultrasound-treated sample. In addition, immunohistochemical staining, using murine TNF-α polyclonal antibody, failed to detect tumor necrosis factor-α (TNF-α) protein in the ultrasound-treated sample compared with the control. An in vitro study showed that the lipopolysaccharide (LPS)-induced expression of Tnfalpha mRNA was significantly reduced by ultrasound therapy in both osteoblastic and cementoblastic cells. Moreover, the TNF-α-induced up-regulation of Rankl mRNA was also inhibited by ultrasound. Conclusion: Ultrasound may contribute to the reduction of the trauma-induced inflammatory reaction through impairment of the TNF-α signaling pathway. It is therefore suggested that ultrasound shows potential as a therapeutic tool to optimize the regenerative potential of periodontal tissues on replanted teeth. [ABSTRACT FROM AUTHOR]

Öztürk A, Yıldız L. Expression of transient receptor potential vanilloid receptor 1 and toll-like receptor-4 in aggressive periodontitis and in chronic periodontitis. J Periodont Res 2011; 46: 475-482. © 2011 John Wiley & Sons A/S [ABSTRACT FROM AUTHOR]

Stein SH, Dean IN, Rawal SY, Tipton DA. Statins regulate interleukin-1β - induced RANKL and osteoprotegerin production by human gingival fibroblasts. J Periodont Res 2011; 46: 483-490. © 2011 John Wiley & Sons A/S [ABSTRACT FROM AUTHOR]

Kaner D, Bernimoulin J-P, Dietrich T, Kleber B-M, Friedmann A. Calprotectin levels in gingival crevicular fluid predict disease activity in patients treated for generalized aggressive periodontitis. J Periodont Res 2011; 46: 417-426. © 2011 John Wiley & Sons A/S [ABSTRACT FROM AUTHOR]

Lei L, Li H, Yan F, Li Y, Xiao Y. Porphyromonas gingivalis lipopolysaccharide alters atherosclerotic-related gene expression in oxidized low-density-lipoprotein-induced macrophages and foam cells. J Periodont Res 2011; 46: 427-437. © 2011 John Wiley & Sons A/S [ABSTRACT FROM AUTHOR]

Yoshihara A, Hayashi Y, Miyazaki H. Relationships among bone turnover, renal function and periodontal disease in elderly Japanese. J Periodont Res 2011; 46: 491-496. © 2011 John Wiley & Sons A/S [ABSTRACT FROM AUTHOR]

Nogueira-Filho G, Xiang XM, Shibli JA, Duarte PM, Sowa MG, Ferrari DS, Onuma T, de Cardoso LAG, Liu K-Z. On site noninvasive assessment of peri-implant inflammation by optical spectroscopy. J Periodont Res 2011; 46: 382-388. © 2011 John Wiley & Sons A/S Optical spectroscopy has been proposed to measure regional tissue hemodynamics in periodontal tissue. The objective of this study was to further evaluate the diagnostic potential of optical spectroscopy in peri-implant inflammation in vivo by assessing multiple inflammatory parameters (tissue oxygenation, total tissue hemoglobin, deoxyhemoglobin, oxygenated hemoglobin and tissue edema) simultaneously. A cross-sectional study was performed in a total of 64 individuals who presented with dental implants in different stages of inflammation. In brief, visible-near-infrared spectra were obtained, processed and evaluated from healthy ( n = 151), mucositis ( n = 70) and peri-implantitis sites ( n = 75) using a portable spectrometer. A modified Beer-Lambert unmixing model that incorporates a nonparametric scattering loss function was employed to determine the relative contribution of each inflammatory component to the overall spectrum. Tissue oxygenation at peri-implantitis sites was significantly decreased ( p < 0.05) when compared with that at healthy sites, which was largely due to an increase in deoxyhemoglobin and a decrease in oxyhemoglobin at the peri-implantitis sites compared with the mucositis and healthy sites. In addition, the tissue hydration index derived from the optical spectra in mucositis was significantly higher than that in other groups ( p < 0.05). In summary, the results of this study revealed that hemodynamic alterations can be detected around diseased peri-implant sites by optical spectroscopy, and this method may be considered an alternative and feasible approach for the monitoring and diagnosis of peri-implant diseases. [ABSTRACT FROM AUTHOR]

Elamin A, Albandar JM, Poulsen K, Ali RW, Bakken V. Prevalence ofAggregatibacter actinomycetemcomitans in Sudanese patients with aggressive periodontitis: a case-control study. J Periodont Res 2011; 46: 285-291.© 2011 John Wiley & Sons A/S Aggregatibacter actinomycetemcomitans is considered a possible etiological agent for aggressive periodontitis. The aim of this study was to determine the prevalence of the JP2 clone and non-JP2 genotypes of A. actinomycetemcomitans in the subgingival plaque of patients with aggressive periodontitis and controls among Sudanese high-school students. In a previous study we examined a large representative sample of students attending high schools in Khartoum, Sudan. In this population, 17 patients with aggressive periodontitis and 17 controls (14-19 years of age) consented to participate in the present study. The subjects underwent a clinical periodontal examination, and subgingival dental plaque samples were collected using paper points. The presence of the A. actinomycetemcomitans JP2 clone and non-JP2 genotypes were assessed using loop-mediated isothermal amplification (LAMP) and the PCR. The JP2 clone of A. actinomycetemcomitans was not detected in the subgingival plaque of either the cases or the controls. Non-JP2 types of A. actinomycetemcomitans were detected in the subgingival plaque of 12 (70.6%) patients with aggressive periodontitis and from only one (5.9%) control subject, showing a significantly higher frequency of detection in cases than in controls ( p = 0.0001). The odds ratio for the detection of A. actinomycetemcomitans in the subgingival plaque of the patients with aggressive periodontitis was 38.4 (95% confidence interval: 4.0-373.0; p = 0.002). The PCR and LAMP methods showed identical results pertaining to the identification of non-JP2 types of A. actinomycetemcomitans. The JP2 clone of A. actinomycetemcomitans was not detected in the subgingival plaque of high school subjects in Sudan. The detection of non-JP2 types of A. actinomycetemcomitans may be a useful marker of increased risk for development of aggressive periodontitis in young subjects. [ABSTRACT FROM AUTHOR]

Faveri M, Gonçalves LFH, Feres M, Figueiredo LC, Gouveia LA, Shibli JA, Mayer MPA. Prevalence and microbiological diversity of Archaea in peri-implantitis subjects by 16S ribosomal RNA clonal analysis. J Periodont Res 2011; 46: 338-344. © 2011 John Wiley & Sons A/S This study evaluated the prevalence and the molecular diversity of Archaea in the subgingival biofilm samples of subjects with peri-implantitis. Fifty subjects were assigned into two groups: Control ( n = 25), consisting of subjects with healthy implants; and Test ( n = 25), consisting of subjects with peri-implantitis sites, as well as a healthy implant. In the Test group, subgingival biofilm samples were taken from the deepest sites of the diseased implant. In both groups, subgingival biofilm was collected from one site with a healthy implant and from one site with a periodontally healthy tooth. DNA was extracted and the 16S ribosomal RNA gene was amplified with universal primer pairs for Archaea. Amplified genes were cloned and sequenced, and the phylotypes were identified by comparison with known 16S ribosomal RNA sequences. In the Control group, Archaea were detected in two and three sites of the implant and the tooth, respectively. In the Test group, Archaea were detected in 12, 4 and 2 sites of diseased implants, healthy implants and teeth, respectively. Diseased implants presented a significantly higher prevalence of Archaea in comparison with healthy implants and natural teeth, irrespective of group. Over 90% of the clone libraries were formed by Methanobrevibacter oralis, which was detected in both groups. Methanobacterium congelense/curvum was detected in four subjects from the Test group and in two subjects from the Control group. Although M. oralis was the main species of Archaea associated with both healthy and diseased implant sites, the data indicated an increased prevalence of Archaea in peri-implantitis sites, and their role in pathogenesis should be further investigated. [ABSTRACT FROM AUTHOR]

Montreekachon P, Chotjumlong P, Bolscher JGM, Nazmi K, Reutrakul V, Krisanaprakornkit S. Involvement of P2X purinergic receptor and MEK1/2 in interleukin-8 up-regulation by LL-37 in human gingival fibroblasts. J Periodont Res 2011; 46: 327-337.© 2011 John Wiley & Sons A/S The antimicrobial peptide LL-37, derived from human neutrophils, can directly chemoattract leukocytes and up-regulate the expression of several immune-related genes in various cell types. In this study, we wanted to determine the immunoregulatory effect of LL-37 on interleukin-8 (IL-8) expression in human gingival fibroblasts (HGFs) and to characterize intracellular signaling pathway(s) and receptor(s) involved in IL-8 induction. Cultured fibroblasts were treated with different concentrations of LL-37 or interleukin-1β (IL-1β), as a positive control, for specific periods of time in the presence or absence of various inhibitors. RT-PCR and real-time PCR were conducted to analyze the expression of IL-8 mRNA, and the IL-8 levels in cell-free culture media were measured using ELISAs. The MTT assay was performed to determine the cytotoxicity of LL-37. Nontoxic concentrations of LL-37 (up to 10 μ) and IL-1β significantly up-regulated the expression of IL-8 mRNA in a dose-dependent manner ( p < 0.05). The IL-8 protein levels were consistently significantly elevated in conditioned media of LL-37-treated HGFs ( p < 0.05). IL-8 up-regulation by LL-37 was completely abrogated by 20 μ U0126, consistent with transient phosphorylation of p44/42 MAP kinases. Moreover, pretreatment with Brilliant Blue G (a selective antagonist of the P2X receptor) and the neutralizing antibody against P2X blocked IL-8 up-regulation in a dose-dependent manner, consistent with expression of the P2X receptor in HGFs. These findings indicate that LL-37 induces IL-8 expression via the P2X receptor and the MEK1/2-dependent p44/42 MAP kinases in HGFs, suggesting both direct and indirect involvement of LL-37 in neutrophil recruitment into an inflammatory site within diseased periodontal tissues. [ABSTRACT FROM AUTHOR]

Ayon Haro ER, Ukai T, Yokoyama M, Kishimoto T, Yoshinaga Y, Hara Y. Locally administered interferon-γ accelerates lipopolysaccharide-induced osteoclastogenesis independent of immunohistological RANKL upregulation. J Periodont Res 2011; 46: 361-373. © 2011 John Wiley & Sons A/S Interferon-γ (IFN-γ) potently inhibits RANKL-induced osteoclastogenesis in vitro. In contrast, previous studies have shown that an increase in IFN-γ expression is correlated with an increase in lipopolysaccharide (LPS)-induced bone loss in vivo. However, it is not clear whether local IFN-γ accelerates osteoclastogenesis or not in vivo. Therefore, the aim of this study was to clarify the role of local IFN-γ in LPS-induced osteoclastogenesis. We induced bone loss in calvaria by injecting LPS. One group of mice received an IFN-γ injection together with LPS injection, while another group received IFN-γ 2 d after LPS injection. Bone resorption was observed histologically. Next, we stimulated murine bone marrow macrophages with macrophage-colony stimulating factor and RANKL in vitro. We added different doses of IFN-γ and/or LPS at 0 or 48 h time points. Cells were stained with tartrate-resistant acid phosphatase at 72 h. Local administration of IFN-γ together with LPS injection did not affect osteoclast formation. However, IFN-γ injected after LPS injection accelerated osteoclast formation. Also, we confirmed that IFN-γ added at 0 h inhibited RANKL-induced osteoclastogenesis in vitro. However, inhibition by IFN-γ added at 48 h was reduced compared with that by IFN-γ added at 0 h. Interestingly, IFN-γ together with a low concentration of LPS accelerated osteoclast formation when both were added at 48 h compared with no addition of IFN-γ. The results suggest that local IFN-γ accelerates osteoclastogenesis in certain conditions of LPS-induced inflammatory bone loss. [ABSTRACT FROM AUTHOR]

Lossdörfer S, Kraus D, Abuduwali N, Jäger A. Intermittent administration of PTH(1-34) regulates the osteoblastic differentiation of human periodontal ligament cells via protein kinase C- and protein kinase A-dependent pathwaysin vitro . J Periodont Res 2011; 46: 318-326. © 2011 John Wiley & Sons A/S Intermittent parathyroid hormone (PTH) is recognized as an anabolic agent in regenerative treatment strategies for bony tissues. Periodontal ligament (PDL) cells share features that are typical of osteoblasts, including an osteoblast-like response to stimulation with PTH, which implies a role for these cells in the regulation of repair processes following inflammatory periodontal disease. In the present study we explored the effect of intermittent administration of a PTH fragment [PTH(1-34)] on the osteoblastic differentiation of human PDL cells in vitro, and we investigated the signaling pathways used by the cells to mediate this effect. PDL cells at two stages of confluence were characterized and used as a model for the role of cell maturation in the cellular response. In preconfluent, less mature cultures, intermittent administration of PTH(1-34) and PTH(1-31) fragments increased alkaline phosphatase (ALP) activity and osteocalcin production, whereas intermittent administration of PTH(3-34) and PTH(7-34) had no effect. RO-32-0432, a specific protein kinase C inhibitor, did not inhibit the PTH(1-34) effect, whereas the protein kinase A inhibitor, H8, antagonized the PTH(1-34)-induced increase in ALP activity and osteocalcin. In contrast, in confluent, more mature cultures, intermittent administration of PTH(1-34), PTH(3-34) and PTH(7-34) fragments, but not of the PTH(1-31) fragment, decreased ALP activity, and osteocalcin and RO-32-0432, but not H8, inhibited the effect. This study showed that the PTH(1-34) effect on ALP activity and osteocalcin production in human PDL cells is maturation state-dependent and specific in terms of the pathways involved. Whereas in less mature cells the PTH effect is associated with cyclic AMP/protein kinase A-dependent signaling, more mature cells seem to mediate the PTH signal primarily via protein kinase C-dependent pathways. [ABSTRACT FROM AUTHOR]

Abe D, Kubota T, Morozumi T, Shimizu T, Nakasone N, Itagaki M, Yoshie H. Altered gene expression in leukocyte transendothelial migration and cell communication pathways in periodontitis-affected gingival tissues. J Periodont Res 2011; 46: 345-353. © 2011 John Wiley & Sons A/S Gene expression is related to the pathogenesis of periodontitis and plays a crucial role in local tissue destruction and disease susceptibility. The aims of the present study were to identify the expression of specific genes and biological pathways in periodontitis-affected gingival tissue using microarray and quantitative real-time RT-PCR analyses. Healthy and periodontitis-affected gingival tissues were taken from three patients with severe chronic periodontitis. Total RNAs from six gingival tissue samples were used for microarray analyses. Data-mining analyses, such as comparisons, gene ontology and pathway analyses, were performed and biological pathways with a significant role in periodontitis were identified. In addition, quantitative real-time RT-PCR analysis was performed on samples obtained from 14 patients with chronic periodontitis and from 14 healthy individuals in order to confirm the results of the pathway analysis. Comparison analyses found 15 up-regulated and 13 down-regulated genes (all of which showed a change of more than twofold in expression levels) in periodontitis-affected gingival tissues. Pathway analysis identified 15 up-regulated biological pathways, including leukocyte transendothelial migration, and five down-regulated pathways, including cell communication. Quantitative real-time RT-PCR verified that five genes in the leukocyte transendothelial migration pathway were significantly up-regulated, and four genes in the cell communication pathway were significantly down-regulated, which was consistent with pathway analysis. We identified up-regulated genes ( ITGB-2, MMP-2, CXCL-12, CXCR-4 and Rac-2) and down-regulated genes (connexin, DSG-1, DSC-1 and nestin) in periodontitis-affected gingival tissues; these genes may be related to the stimulation of leukocyte transendothelial migration and to the the impairment of cell-to-cell communication in periodontitis. [ABSTRACT FROM AUTHOR]

Choi J, Lee S-Y, Kim K, Choi B-K. Identification of immunoreactive epitope of Porphyromonas gingivalis heat shock protein peptide in periodontitis and atherosclerosis. J Periodont Res 2011; 46: 240-245. © 2011 John Wiley & Sons A/S Heat shock protein 60 (HSP60) of Porphyromonas gingivalis, a major periodontal pathogen, might be a trigger molecule linking infectious periodontitis and autoimmune atherosclerosis. The aim of this study was to identify the peptide specificity of anti- P. gingivalis HSP60 monoclonal antibodies and their cross-reactivity with bacterial and human HSPs. Their specific immunoreactivity to periodontal or atherosclerotic lesions was also investigated. Twenty patients with chronic periodontitis and 20 atherosclerosis patients who had undergone surgical intervention for atheromatous plaques with evidence of ongoing periodontal disease, were selected. Synthetic peptide 19 ((TLVVNRLRGSLKICAVKAPG)-specific T-cell lines were established from inflamed gingiva and atheromatous plaque and the phenotypes and cytokine profiles were characterized. Thirty per cent of periodontitis patients and 100% of atherosclerosis patients reacted positively to cross-reactive peptide 19 from both P. gingivalis and human HSP60. The peptide 19-specific T-cell lines demonstrated the phenotype characteristic of helper T cells (CD4) but did not express CD25 or FOXP3. The interleukin-10 levels were elevated significantly in the peptide 19 T-cell line. Synthetic peptide 19 of P. gingivalis HSP60 is an immunoreactive epitope in the periodontitis-atherosclerosis axis. [ABSTRACT FROM AUTHOR]

Chiang C-Y, Tu H-P, Chen Y-T, Chin Y-T, Lai T-M, Chiu H-C, Nieh S, Fu E. Up-regulation of retinoblastoma protein phosphorylation in gingiva after cyclosporine A treatment: an in vivo and in vitro study. J Periodont Res 2011; 46: 158-163. © 2010 John Wiley & Sons A/S Cyclosporine A can induce gingival cell proliferation; however, the precise molecular regulation of the proliferation is uncertain. Therefore, this study was carried out to examine, in vivo and in vitro, the expression of genes and proteins associated with gingival cell proliferation after treatment with cyclosporine A. Forty Sprague Dawley rats with right maxillary posterior edentulous gingivae were assigned to a cyclosporine A group (30 mg/kg daily of cyclosporine A, administered orally) or a control group (administered mineral oil only). The animals were killed 4 wk after treatment. The edentulous gingivae were dissected out and analyzed for the expression of proliferating cell nuclear antigen (PCNA), cyclin D1, cyclin-dependent kinase 4 (CDK4) and retinoblastoma protein (Rb1) mRNA and/or protein, and phosphorylated Rb1 (pRb1), by real-time RT-PCR or immunohistochemistry. In human gingival fibroblast (HGF) cultures, the expression of PCNA, CDK4, cyclin D1 and Rb1 proteins and Rb1 phosphorylation were determined by western blotting after cyclosporine A treatment (0-10 ng/mL). Proliferating cell nuclear antigen and cyclin D1 mRNAs ( Pcna and Ccnd1, respectively) were expressed more strongly in the gingivae of cyclosporine A-treated animals than in the gingivae of the controls. Immunohistochemical analyses showed that a greater number of gingival cells stained positive for cyclin D1, CDK4 and pRb1 in the cyclosporine A group than in the control group. Increased expression of cyclin D1, CDK4 and PCNA proteins was observed in HGFs after cyclosporine A treatment. The phosphorylation of Rb1 was enhanced in HGFs after treatment with cyclosporine A at concentrations of 10-10 ng/mL. The increases in cyclin D1, PCNA and CDK4, together with the enhanced phosphorylation of Rb1, suggest that cyclosporine A promotes cell-cycle progression through the G/S transition in the gingiva. [ABSTRACT FROM AUTHOR]

Soysa NS, Alles N, Takahashi M, Aoki K, Ohya K. Defective nuclear factor-κB-inducing kinase in aly/aly mice prevents bone resorption induced by local injection of lipopolysaccharide. J Periodont Res 2011; 46: 280-284. © 2010 John Wiley & Sons A/S Nuclear factor-κB (NF-κB) is activated at sites of inflammation in many diseases, including periodontitis. Nuclear factor-κB induces the transcription of proinflammatory cytokines, resulting in increased osteoclastogenesis and bone resorption. Recently, it has been shown that the NF-κB alternative pathway is important for maintainance of physiological bone homeostasis. Activation of this pathway is by processing of the inhibitor p100 into the active subunit p52 by nuclear factor-κB-inducing kinase (NIK). Defective NIK in aly/ aly mice (NIK) causes mild osteopetrosis and blunted RANKL-stimulated osteoclastogenesis in vivo and in vitro, suggesting that NIK is necessary for basal and stimulated osteoclastogenesis. Nevertheless, the role of NIK in pathological bone resorption is not well investigated. The present study was undertaken to investigate the role of NIK in lipopolysaccharide (LPS)-induced inflammatory bone resorption using aly/ aly mice. Mice were injected with LPS over the calvariae and killed 5 d later. Calvariae were subjected to radiological analysis. Histological sections were stained for tartrate-resistant acid phosphatase, and histomorphometric analysis was performed to quantify the number of osteoclasts and the area of bone resorption. Lipopolysaccharide-induced inflammation was observed in wild-type and aly/+ mice but not in aly/ aly mice. Lipopolysaccharide significantly reduced the calvarial bone mineral density in wild-type and aly/+ mice, whereas bone mineral density was comparable in LPS- and vehicle-injected aly/ aly mice. In addition, aly/ aly mice were resistant to LPS-induced bone resorption and osteoclastogenesis. Taken together, these data show that NIK is important in the bone-destructive components of inflammation and represents a possible therapeutic target. [ABSTRACT FROM AUTHOR]

Aoyama N, Suzuki J, Wang D, Ogawa M, Kobayashi N, Hanatani T, Takeuchi Y, Izumi Y, Isobe M. Porphyromonas gingivalis promotes murine abdominal aortic aneurysms via matrix metalloproteinase-2 induction. J Periodont Res 2011; 46: 176-183. © 2010 John Wiley & Sons A/S Abdominal aortic aneurysm (AAA) is a common and lethal disorder, and MMPs are highly expressed in AAA lesions. Large numbers of periodontopathic bacteria have been reported to be present in specimens obtained from the aortic walls of patients with an AAA. The purpose of this study was to analyze the influence of periodontopathic bacteria on AAA dilatation. AAAs were produced in mice by the periaortic application of 0.25 CaCl, and NaCl was used as a control. The mice were inoculated once weekly with live Porphyromonas gingivalis, live Aggregatibacter actinomycetemcomitans or vehicle. Four weeks after the periaortic application of either CaCl or NaCl, a significant increase was observed in the aortic diameter of P. gingivalis-challenged mice compared with the vehicle control mice ( p < 0.05), whereas there was no statistically significant increase in the aortic diameter of the A. actinomycetemcomitans-challenged mice. Immunohistochemical analysis found significantly higher numbers of CD8-positive and MOMA2-positive cells and significantly higher levels of MMP-2 in the aneurysmal samples of P. gingivalis-challenged mice compared with control mice. Live P. gingivalis promoted a significant proliferation of splenocytes in comparison with P. gingivalis-lipopolysaccharide and live A. actinomycetemcomitans ( p < 0.05). These findings demonstrate that challenge with P. gingivalis, but not with A. actinomycetemcomitans, can accelerate, or even initiate, the progression of experimental AAA through the increased expression of MMPs. [ABSTRACT FROM AUTHOR]

Brage M, Holmlund A, Johansson A. Humoral immune response toAggregatibacter actinomycetemcomitans leukotoxin. J Periodont Res 2011; 46: 170-175. © 2010 John Wiley & Sons A/S Periodontal disease is an inflammatory condition caused by bacterial infections that result in loss of the tooth supporting tissue. The periodontal pathogens produce virulence factors with capacity to affect the host immune response. Aggregatibacter actinomycetemcomitans is a periodontal pathogen that produces a leukotoxin that specifically affects human leukocytes. The aims of the present study were to examine the presence and function of systemic antibodies to the leukotoxin. One hundred and ninety-seven middle-aged (57 ± 5 years) Swedes with well-documented periodontal status and medical factors related to cardiovascular diseases were studied. These data have been published previously. The serum samples were examined for the presence of leukotoxin antibodies by western blot and the capacity to neutralize leukotoxicity in an activity assay with leukotoxin and cultured leukemic cells. The results showed a high prevalence (57%) of antibodies against A. actinomycetemcomitans leukotoxin in the analyzed population. These antibodies were correlated with leukotoxin neutralizing capacity as well as with the ELISA titers of A. actinomycetemcomitans-specific IgA and IgG. In addition, high levels of leukotoxin antibodies were correlated with increasing age, but not with periodontal disease parameters or cardiovascular risk factors. Systemic antibodies against A. actionmycetemcomitans leukotoxin were common in this adult Swedish population. These antibodies might contribute to limit the systemic effects of the infection. [ABSTRACT FROM AUTHOR]