Epidemiological studies suggest that the severity of periodontitis is higher in people with diabetes than in healthy individuals. Insulin resistance might play a crucial role in the pathogenesis of multiple diabetic complications and is reportedly induced in the gingiva of rodents with type 2 diabetes; however, the molecular mechanisms underlying the pathogenesis of diabetes-related periodontitis remain unclear. Therefore, we aimed to investigate whether endothelial insulin resistance in the gingiva may contribute to the pathogenesis of periodontitis as well as elucidate its underlying molecular mechanisms. We demonstrated that insulin treatment downregulated lipopolysaccharide (LPS)-induced or tumor necrosis factor α (TNFα)-induced VCAM1 expression in endothelial cells (ECs) via the PI3K/Akt activating pathway, resulting in reduced cellular adhesion between ECs and leukocytes. Hyperglycemia-induced selective insulin resistance in ECs diminished the effect of insulin on LPS- or TNFα-stimulated VCAM1 expression. Vascular endothelial cell-specific insulin receptor knockout (VEIRKO) mice exhibited selective inhibition of the PI3K/Akt pathway in the gingiva and advanced experimental periodontitis-induced alveolar bone loss via upregulation of Vcam1, Tnfα, Mcp-1, Rankl, and neutrophil migration into the gingiva compared with that in the wild-type (WT) mice despite being free from diabetes. We also observed that insulin-mediated activation of FoxO1, a downstream target of Akt, was suppressed in the gingiva of VEIRKO and high-fat diet (HFD)-fed mice, hyperglycemia-treated ECs, and primary ECs from VEIRKO. Further analysis using ECs transfected with intact and mutated FoxO1, with mutations at 3 insulin-mediated phosphorylation sites (T24A, S256D, S316A), suggested that insulin-mediated regulation of VCAM1 expression and cellular adhesion of ECs with leukocytes was attenuated by mutated FoxO1 overexpression. These results suggest that insulin resistance in ECs may contribute to the progression of periodontitis via dysregulated VCAM1 expression and cellular adhesion with leukocytes, resulting from reduced activation of the PI3K/Akt/FoxO1 axis.

Background Breast cancer is the most common cancer in women and its metastasis markedly exacerbates patients’ prognosis. In particular, triple negative breast cancer (TNBC), which lacks estrogen receptors (ER), progesterone receptors (PR) and human epidermal growth factor receptor 2 (HER2), is an aggressive subtype of breast cancer frequently forming metastatic lesions. Differentiation-inducing factor-1 (DIF-1) identified in Dictyostelium discoideum inhibits cell proliferation and migration of various mammalian cancer cells. However, the effect of DIF-1 on TNBC has not been examined. Here, we investigated whether DIF-1 shows anti-proliferative and anti-metastatic effects on TNBC by in-vivo and in-vitro experiments. Methods In in-vivo experiments, we used cancer xenograft model mice in which murine TNBC 4T1/Luc cells (1.0 × 106 cells/mL) were injected into mammary fat pads to evaluate the effects of intragastric administration of DIF-1 (300 mg/kg/day) on the primary tumor growth and lung metastasis. In in-vitro experiments, we carried out assays for cell proliferation, migration and invasion to evaluate the anti-proliferative and anti-metastatic effects of DIF-1. We also conducted Western blotting and real-time RT-PCR to identify the mechanisms for DIF-1’s anti-cancer effects. Results In vivo, administration of DIF-1 significantly suppressed the primary tumor growth and lung metastasis without adverse effects such as weight loss and myelosuppression. In vitro, DIF-1 reduced cyclin D1 and c-Myc by inhibiting transcription and promoting degradation of the proteins, which resulted in the suppression of cell proliferation. DIF-1 also suppressed cell migration and invasion and reduced the protein expressions of snail, twist, vimentin and MMP-2, crucial factors in epithelial-mesenchymal transition (EMT). Conclusions DIF-1 exerts anti-cancer effects in TNBC by reducing cell cycle accelerators and reversing EMT. Our findings suggest that using DIF-1 as a lead compound could develop a novel anti-cancer agent for TNBC. Legal entity responsible for the study The study protocol was approved by the Committee on Ethics of Animal Experiments of Kyushu University. Animal handling and procedures were carried out in compliance with the Guidelines for Animal Experiments, Kyushu University, and the Law (No. 105) and Notification (No. 6) of the Japanese Government. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.

Background: The diagnosis of the progression of periodontitis presently depends on the use of clinical symptoms (such as attachment loss) and radiographic imaging. The aim of the multicenter study described here was to evaluate the diagnostic use of the bacterial content of subgingival plaque recovered from the deepest pockets in assessing disease progression in chronic periodontitis patients.Methods: This study consisted of a 24-month investigation of a total of 163 patients with chronic periodontitis who received trimonthly follow-up care. Subgingival plaque from the deepest pockets was recovered and assessed for bacterial content of Porphyromonas gingivalis, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans using the modified Invader PLUS assay. The corresponding serum IgG titers were measured using ELISA. Changes in clinical parameters were evaluated over the course of 24 months. The sensitivity, specificity, and prediction values were calculated and used to determine cutoff points for prediction of the progression of chronic periodontitis.Results: Of the 124 individuals who completed the 24-month monitoring phase, 62 exhibited progression of periodontitis, whereas 62 demonstrated stable disease. The P. gingivalis counts of subgingival plaque from the deepest pockets was significantly associated with the progression of periodontitis (p < 0.001, positive predictive value = 0.708).Conclusions: The P. gingivalis counts of subgingival plaque from the deepest pockets may be associated with the progression of periodontitis.

Background and aims: Epicatechin (EC) intake has been suggested to be beneficial for the prevention of cardiovascular disorders, and it is well known that adipose tissue inflammation is one of the major risk factors for coronary heart diseases. The purpose of the present study was to determine the in vitro and in vivo effects of EC on adipose tissue inflammation and obesity.Methods and results: DNA microarray analysis was performed to evaluate the effects of EC on gene expression in adipocytes co-cultured with bacterial endotoxin-stimulated macrophages. To determine the in vivo effects of the catechin, C57BL/6 mice were fed either a high-fat diet (HFD) or HFD combined with EC, and metabolic changes were observed EC suppressed the expression of many inflammatory genes in the adipocytes co-cultured with endotoxinstimulated macrophages. Specifically, EC markedly suppressed chemokine (C-C motif) ligand 19 (CCL19) expression. The target cell of EC appeared to macrophages. The in vivo study indicated that mice fed the EC-supplemented HFD were protected from diet-induced obesity and insulin resistance. Accordingly, the expression levels of genes associated with inflammation in adipose tissue and in the liver were downregulated in this group of mice.Conclusions: EC exerts beneficial effects for the prevention of adipose tissue inflammation and insulin resistance. Since we previously reported that mice deficient in the CCL19 receptor were protected from diet-induced obesity and insulin resistance, it can be concluded that the beneficial effects of EC could be mediated, at least in part, by marked suppression of CCL19 expression. (C) 2016 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

BACKGROUND AND OBJECTIVEA diagnosis of periodontitis progression is presently limited to clinical parameters such as attachment loss and radiographic imaging. The aim of this multicenter study was to monitor disease progression in patients with chronic periodontitis during a 24-mo follow-up program and to evaluate the amount of bacteria in saliva and corresponding IgG titers in serum for determining the diagnostic usefulness of each in indicating disease progression and stability.MATERIAL AND METHODSA total of 163 patients with chronic periodontitis who received trimonthly follow-up care were observed for 24 mo. The clinical parameters and salivary content of Porphyromonas gingivalis, Prevotella intermedia and Aggregatibacter actinomycetemcomitans were assessed using the modified Invader PLUS assay, and the corresponding serum IgG titers were measured using ELISA. The changes through 24 mo were analyzed using cut-off values calculated for each factor. One-way ANOVA or Fisher's exact test was used to perform between-group comparison for the data collected. Diagnostic values were calculated using Fisher's exact test.RESULTSOf the 124 individuals who completed the 24-mo monitoring phase, 62 exhibited periodontitis progression, whereas 62 demonstrated stable disease. Seven patients withdrew because of acute periodontal abscess. The ratio of P. gingivalis to total bacteria and the combination of P. gingivalis counts and IgG titers against P. gingivalis were significantly related to the progression of periodontitis. The combination of P. gingivalis ratio and P. gingivalis IgG titers was significantly associated with the progression of periodontitis (p = 0.001, sensitivity = 0.339, specificity = 0.790).CONCLUSIONSIt is suggested that the combination of P. gingivalis ratio in saliva and serum IgG titers against P. gingivalis may be associated with the progression of periodontitis.

OBJECTIVES:We previously demonstrated that a dominant-negative Sprouty2 (Spry2) mutation promotes osteoblast proliferation and differentiation after basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) stimulation, whereas it diminishes proliferation of gingival epithelial cells, thereby inducing favourable conditions for periodontal tissue regeneration. In this study, we investigated how Spry2 inhibition affects the cellular physiology of periodontal ligament (PDL) cells.METHODS:A total of 1-17 PDL cells (multipotent clonal human PDL cell line) were stimulated with bFGF and EGF after transfection of Spry2 siRNA. Cell proliferation, migration, ALP staining, real-time PCR, Western blot and immunofluorescence assays were performed.RESULTS:ERK1/2 activation and proliferation of 1-17 PDL cells were significantly upregulated by the addition of Spry2 siRNA in the presence of bFGF and EGF. In addition, Spry2 siRNA reduced transcription of osteogenesis-related genes and ALP staining relative to control cells. Furthermore, it increased AKT/phosphatidylinositol 3-kinase (PI3K) phosphorylation; consequently, Rac1 but not Cdc42 was activated, thereby promoting lamellipodia formation, cell proliferation and migration after stimulation by bFGF and EGF.CONCLUSION:Spry2 combined with bFGF and EGF stimulation reduced PDL cell migration and proliferation with inducing osteoblastic differentiation. These in vitro findings may provide a molecular basis for novel therapeutic approaches for establishing periodontal tissue regeneration.

SummaryNatural competence is the ability of bacteria to incorporate extracellular DNA into their genomes. This competence is affected by a number of factors, including Ca2+ utilization and biofilm formation. As bacteria can form thick biofilms in the presence of extracellular Ca2+, the additive effects of Ca2+‐promoted biofilm formation on natural competence should be examined. We evaluated natural competence in Aggregatibacter actinomycetemcomitans, an important periodontal pathogen, in the context of Ca2+‐promoted biofilms, and examined whether the pga gene cluster, required for bacterial cell aggregation, is necessary for competence development. The A. actinomycetemcomitans cells grown in the presence of 1 mm CaCl2 exhibited enhanced cell aggregation and increased levels of cell‐associated Ca2+. Biofilm‐derived cells grown in the presence of Ca2+ exhibited the highest levels of natural transformation frequency and enhanced expression of the competence regulator gene, tfoX. Natural competence was enhanced by the additive effects of Ca2+‐promoted biofilms, in which high levels of pga gene expression were also detected. Mutation of the pga gene cluster disrupted biofilm formation and competence development, suggesting that these genes play a critical role in the ability of A. actinomycetemcomitans to adapt to its natural environment. The Ca2+‐promoted biofilms may enhance the ability of bacteria to acquire extracellular DNA.

Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans are major periodontal pathogens that cause several types of periodontal disease. Our previous study suggested that P. gingivalis gingipains secreted in the subgingival environment are related to the detachment of A.actinomycetemcomitans biofilms. However, it remains unclear whether arginine-specific cysteine proteinase (Rgp) and lysine-specific proteinase (Kgp) play different roles in the detachment of A. actinomycetemcomitans biofilm. The aim of this study was to investigate possible disruptive roles of Kgp and Rgp in the aggregation and attachment of A. actinomycetemcomitans. While P. gingivalis ATCC33277 culture supernatant has an ability to decrease autoaggregation and coaggregation of A. actinomycetemcomitans cells, neither the boiled culture supernatant of ATCC33277 nor the culture supernatant of KDP136 showed this ability. The addition of KYT-1 and KYT-36, specific inhibitors of Rgp and Kgp, respectively, showed no influence on the ability of P. gingivalis culture supernatant. The result of gelatin zymography suggested that other proteases processed by gingipains mediated the decrease of A. actinomycetemcomitans aggregations. We also examined the biofilm-destructive effect of gingipains by assessing the detachment of A. actinomycetemcomitans from polystyrene surfaces. Scanning electron microscope analysis indicated that A. actinomycetemcomitans cells were detached by P. gingivalis Kgp. The quantity of A. actinomycetemcomitans in biofilm was decreased in co-culture with P. gingivalis. However, this was not found after the addition of KYT-36. These findings suggest that Kgp is a critical component for the detachment and decrease of A. actinomycetemcomitans biofilms.

Several lines of evidence have suggested a role of gut microbiota in the etiology of nonalcoholic steatohepatitis (NASH). NASH subjects reportedly showed a prolonged orocecal transit time coexistent with small intestinal bacterial overgrowth. We considered the possibility that enhanced gastrointestinal motility would influence gut microbiota and thus investigated the effects of the gastroprokinetic agent mosapride citrate (MC) on gut microbiota and the development of NASH using a methionine-choline deficient (MCD) diet-fed rodent model. Mice were divided into three groups, given the normal chow diet (NCD), the MCD diet, or the MCD diet containing 10 mg·kg(-1)·day(-1) of MC (MCD plus MC) for 6 wk. NASH development was evaluated based on hepatic histochemical findings, serum parameters and various mRNA and/or protein expression levels. MC treatment suppressed MCD diet-induced NASH development, with reduced serum lipopolysaccharide and increased plasma glucagon-like peptide-1 (GLP-1) concentrations. Calculation of the relative abundance of each strain based on gut microbiota analyses indicated lactic acid bacteria specifically, such as Bifidobacterium and Lactobacillus, in feces to be decreased in the MCD, compared with the NCD group. Interestingly, the reduction in lactic acid bacteria in the MCD diet group was reversed in the MCD plus MC group. In addition, colon inflammation observed in the MCD diet group was reduced in the MCD plus MC group. Therefore, MC showed a protective effect against MCD diet-induced NASH development in our rodent model, with possible involvements of increased fecal lactic acid bacteria, protection against colon inflammation and elevated plasma GLP-1.

BACKGROUND:Azithromycin is an antibiotic belonging to the macrolides. Previous case reports showed that azithromycin has a regenerative effect on periodontal tissue in addition to improving periodontal gingival inflammation. Recently, we experienced three periodontitis cases, all of which showed severe bone loss. However, their gingival inflammatory signs differed greatly. The present case reports evaluated the regenerative effects of azithromycin on periodontitis sites with different clinical signs of gingival inflammation.METHODS:In Case 1, generalized chronic periodontitis with severe gingival inflammation was treated with azithromycin before periodontal treatment. In contrast, Case 2 presented with few clinical signs of gingival inflammation, but was treated with azithromycin prescribed within a day of scaling and root planing. In Case 3, teeth with moderate gingival inflammation were treated with azithromycin after a series of scaling and root planing.RESULTS:Remarkable alveolar bone growth, regardless of baseline gingival inflammation, was noted in all three cases.CONCLUSIONS:The use of adjunctive azithromycin in scaling and root planing may be effective for periodontal tissue regeneration. This property may be independent of the degree of baseline gingival inflammation.

AIM:To find possible reagents to minimize inflammatory responses by using an established pulpitis models for the purpose of developing new pulp-capping materials, and to test the possible use of phosphorylated pullulan as a carrier for such an anti-inflammatory reagent.METHODOLOGY:Co-culturing was performed using transwell systems. Inflammatory responses were evaluated by measuring cytokines produced by the cells. The effects of two flavonoids, luteolin and quercetin, as anti-inflammatory reagents, and phosphorylated pullulan, which potentially achieves a sufficient marginal sealing to hydroxyapatite and slowly releases luteolin, as a carrier for flavonoids, were tested.RESULTS:Flavonols, particularly luteolin, dramatically attenuated inflammatory cytokine production, which was augmented by co-cultures. Luteolin was successfully enclosed by phosphorylated pullulan. Finally, it was confirmed that luteolin released from phosphorylated pullulan was effective in reducing cytokine production by co-cultures.CONCLUSIONS:Combination of phosphorylated pullulan and luteolin could be potentially used in the treatment of dental pulp inflammation.

Yonehiro J, Yamashita A, Yoshida Y, Yoshizawa S, Ohta K, Kamata N, Okihara T, Nishimura F. Establishment of an ex vivo pulpitis model by co‐culturing immortalized dental pulp cells and macrophages. International Endodontic Journal.AbstractAim To establish an ex vivo pulpitis model by co‐culturing dental pulp cells with macrophages.Methodology As dental pulp cells, immortalized human dental pulp cells, named DP‐1, were used, whilst as macrophage cell lines, the differentiated human monocytic cell line, THP‐1, was used. In some experiments, primary dental pulp cells were isolated and used to confirm the results obtained in the experiments using immortalized cells. Co‐culturing was performed using transwell systems. Inflammatory responses were evaluated by measuring cytokines produced by the cells.Results Co‐culturing both cell types markedly up‐regulated inflammatory cytokine production as compared with the cells cultured independently, suggesting that both cell types interact with each other to synergistically produce higher amounts of inflammatory cytokines. Interestingly, both DP‐1 and primary dental pulp cells appeared to produce molecules stimulating macrophages to produce tumour necrosis factor‐α‐.Conclusion Co‐culturing immortalized dental pulp cells and macrophages may be a new ex vivo model for studying the pathophysiology of reversible pulpitis.

BACKGROUND AND OBJECTIVE:The role of human leukocyte histocompatibility antigen (HLA) class II molecules on non-antigen-presenting cells has been a matter of controversy. We previously reported that HLA-II molecules on human gingival fibroblasts (GF) do not present antigens, but transduce signals into the cells, resulting in the expression of several cytokines, such as interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), regulated upon activation, normal T-cell expressed and secreted (RANTES) and IL-8. However, the exact role of these cytokines, as well as other cytokines which are potentially secreted from GF, in the pathogenesis of chronic periodontal inflammation is not fully understood. The aim of this study was to observe the effects of HLA-II-induced cytokines on the proliferation of human umbilical vein endothelial cells (HUVEC).MATERIAL AND METHODS:Antibody-based cytokine-microarray analyses were performed to detect potential cytokines associated with angiogenesis. Next, cytokine productivity was confirmed by quantitative methods. Then, cell proliferation assay was performed to see whether these cytokines promoted the proliferation of HUVEC.RESULTS:Besides IL-6, MCP-1, RANTES and IL-8, growth-related gene product (GRO) was newly identified as an HLA-II-induced cytokine released from GF. This was confirmed by a quantitative method. Cell culture supernatant from HLA-II-stimulated GF cultures promoted the growth of HUVEC. Addition of anti-IL-8 neutralizing antibody, anti-CXC receptor (CXCR)1 antibody and anti-MCP-1 antibody inhibited the growth of HUVEC in a dose-dependent manner, while addition of anti-GROalpha antibody did not.CONCLUSION:The HLA-II-induced IL-8, via CXCR1, as well as MCP-1 from GF, promotes endothelial cell proliferation, which is possibly associated with enhanced angiogenesis in chronic periodontal lesions.

Interleukin (IL)-23 is an essential cytokine involved in expansion of the Th17 lineage, which is associated with many immune-related destructive tissue diseases. We hypothesized that the IL-23-induced Th17 pathway plays a role in periodontal pathology and examined the expression of cytokines, and related molecules, in periodontal lesions and control sites. IL-23 and IL-12 were expressed at significantly higher levels in periodontal lesions than in control sites. However, the relative expression of the IL-23 receptor compared with the IL-12 receptor β2 was significantly higher in periodontal lesions. Moreover, IL-17 expression was significantly higher in periodontal lesions, especially in the tissue adjacent to bone destruction, than in control sites. There was no significant difference in the expression levels of IFN-γ, an important cytokine inhibiting differentiation toward the Th17 pathway, between periodontal lesions and control sites. Together, these results suggest that the IL-23-induced Th17 pathway is stimulated in inflammatory periodontal lesions.

1 Department of Dental Science for Health Promotion, and the 2 Department of Biomedical Chemistry, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Japan and 3 Department of Pathophysiology Periodontal Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan and 4 Department of Biochemistry and Molecular Biology, Nihon University School of Dentistry at Matsudo, Matsudo, Japan.

Recent studies have suggested that macrophages were integrated into adipose tissues to interact with adipocytes, thereby exacerbating inflammatory responses. Furthermore, both adipocytes and macrophages appear to express toll-like receptor-4 (TLR-4), and free fatty acids may stimulate cells through TLR-4. Herein, we analyzed genes differentially expressed in adipocytes when co-cultured with macrophages in the presence of a ligand for TLR-4, bacterial lipopolysaccharide (LPS). RAW264.7, a murine macrophage cell line and differentiated 3T3-L1 adipocytes were co-cultured using a transwell system. Genes differentially expressed in adipocytes were analyzed by the DNA microarray method following 4, 8, 12 and 24 h stimulation with 1 ng ml−1 of Escherichia coli LPS. Randomly selected genes with high expressions were confirmed by quantitative methods at both the gene and the protein level. Co-culture of macrophages and adipocytes with a low LPS concentration (1 ng ml−1) markedly upregulated gene expressions associated with inflammation and/or angiogenesis, such as those of interleukin-6 (IL-6), MCP-1, RANTES and CXCL1/KC, in adipocytes. Furthermore, several genes associated with insulin resistance were differentially expressed. Upregulations of genes encoding MCP-1, RANTES and CXC/KC were confirmed by quantitative methods. These results suggest that ligands for TLR-4 stimulate both adipocytes and macrophages to upregulate the expressions of many genes associated with inflammation and/or angiogenesis.

Short title: HLA II-induced signals in gingival fibroblasts. 1. Department of Patho-physiology Periodontal Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan 2. First Department of Pathology, Hyogo College of Medicine, Hyogo, Japan 3. Department of Allergy and Immunology, Saitama Medical School, Saitama, Japan 4. (current address) Department of Dental Science for Health Promotion, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Japan *Corresponding author: Dr. Fusanori Nishimura, Department of Dental Science for Health Promotion, Hiroshima University Graduate School of Biomedical Sciences, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8553, Japan. E-mail: fusanori@hiroshima-u.ac.jp

BACKGROUND AND OBJECTIVE:The role of human leukocyte antigen class II molecules on nonantigen-presenting cells has been a matter of controversy. We previously reported that human leukocyte antigen class II molecules on human gingival fibroblasts do not present antigens, but transduce signals into the cells by making a complex with antigenic peptide T-cell receptor or by stimulating cell surface human leukocyte antigen-DR molecules with human leukocyte antigen-DR antibody (L243), which mimics the formation of the human leukocyte antigen class II-antigenic peptide T-cell receptor complex, resulting in the expression of several cytokines. The aim of this study was to detect human leukocyte antigen class II-associated molecules mediating human leukocyte antigen class II-induced signals into the cells.MATERIAL AND METHODS:Antibody-based protein-microarray analysis was performed to detect activated signaling molecules in gingival fibroblasts stimulated via human leukocyte antigen class II molecules. Then, we examined if these molecules structurally associate with human leukocyte antigen class II and actually transduce signals into the cells.RESULTS:Stimulation of human leukocyte antigen class II on gingival fibroblasts by L243 resulted in enhanced phosphorylation of focal adhesion kinase. Focal adhesion kinase was co-immunoprecipitated with human leukocyte antigen-DR by L243. Stimulation of gingival fibroblasts with L243 induced phosphorylation of focal adhesion kinase. Luteolin, a putative focal adhesion kinase inhibitor, suppressed phosphorylation of focal adhesion kinase and dose dependently inhibited human leukocyte antigen class II-induced cytokine production.CONCLUSION:Focal adhesion kinase is structurally associated with human leukocyte antigen-DR and mediates human leukocyte antigen class II-induced signals in gingival fibroblasts.