Tetsuo Kobayashi

Niigata University, Niahi-niigata, Niigata, Japan

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Publications (30)73.42 Total impact

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    ABSTRACT: Background: Tumor necrosis factor-alpha (TNF-α) inhibitor has been implicated to have an effect on periodontal condition in patients with rheumatoid arthritis (RA). The aim of the present study is to assess the effect of a fully humanized anti-TNF-α monoclonal antibody adalimumab (ADA) on periodontal condition in patients with RA, and to compare serum protein profiles before and after ADA therapy. Methods: The study participants consisted of 20 patients with RA treated with ADA. Clinical periodontal and rheumatologic parameters and serum cytokine levels were evaluated at baseline and 3 months later. Serum protein spot volume was examined with two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis. Proteins with significant difference in abundance before and after ADA therapy were determined, and identified with mass spectrometry and protein databases. Results: The patients showed a significant decrease in gingival index (P = 0.002), bleeding on probing (P = 0.003), probing depth (P = 0.002), disease activity score including 28 joints using C-reactive protein (P = 0.0004), and serum levels of TNF-α (P = 0.0003) and interleukin-6 (P < 0.0001) after ADA medication, although plaque levels were comparable. Among a total of 495 protein spots obtained, nine spots were significantly decreased in abundance at reassessment, which corresponds to complement factor H, phospholipase D, serum amyloid A, complement component 4, and alpha-1-acid glycoprotein (P < 0.01). Conclusions: These results suggest an beneficial effect of ADA therapy on periodontal condition in patients with RA, which might be related to differences in serum protein profiles before and after ADA therapy.
    Journal of periodontology. 05/2014;
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    ABSTRACT: Background: Porphyromonas gingivalis has been implicated as an etiological agent of rheumatoid arthritis (RA) due to the expression of peptidylarginine deiminase. The present study was undertaken to evaluate whether periodontal treatment may affect serum antibodies to P. gingivalis and citrulline levels in relation to disease activity of RA. Methods: Fifty-five patients with RA were randomly assigned to receive oral hygiene instruction and supragingival scaling (treatment group, n = 26) or no periodontal treatment (control group, n = 29). Periodontal and rheumatologic parameters and serum levels of cytokine and inflammatory markers, citrulline and immunoglobulin G (IgG) to P. gingivalis were examined at baseline and 8 weeks later. Results: Both groups did not differ statistically in all parameters except for % sites with probing depth and clinical attachment level ≥ 4 mm at baseline. The treatment group exhibited a significantly greater decrease in disease activity score including 28 joints using C-reactive protein (DAS28-CRP) (P = 0.02), serum levels of IgG to P. gingivalis hemin binding protein 35 (HBP35) (P = 0.04) and citrulline (P = 0.02) than the control group. Serum levels of IgG to P. gingivalis HBP35 were significantly correlated positively with those of anti-CCP antibodies (P = 0.0002). The same correlation was obtained between serum levels of IgG to P. gingivalis sonicated extracts and those of rheumatoid factor (P = 0.02) Conclusions: These results suggest that supragingival scaling decreases DAS28-CRP and serum levels of IgG to P. gingivalis HBP35 and citrulline in RA patients. These observations may reflect a role of P. gingivalis in the protein citrullination, which is related to the pathogenesis of RA.
    Journal of Periodontology 05/2013; · 2.40 Impact Factor
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    ABSTRACT: Background: Rheumatoid arthritis (RA) and chronic periodontitis (CP) are chronic inflammatory conditions, and share many pathologic features. The common molecular pathogenesis of the two inflammatory diseases is unclear. The aim of the present study was to evaluate serum protein profiles specific for the patients with RA and CP by a comprehensive proteomic analysis. Methods: The study subjects consisted of 10 patients with RA and CP (RA+CP group), 10 patients with RA only (RA group), 10 patients with CP only (CP group), and 10 healthy controls (H group) in age-, gender-, smoking status-balanced condition. Serum protein spot volume was examined with two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis. Proteins with significant difference in abundance among the four groups were determined with a computer image analysis, and identified with mass spectrometry and protein databases. Results: A total of 1,694 protein spots were obtained in sera of the four groups. Seven spots were significantly different in abundance among the four groups. Of these, three spots (complement component 3, complement factor H, and ceruloplasmin) were significantly different in abundance in the RA+CP group compared with other three groups (P < 0.05). The similar profiles of complement component 3, complement factor H, and ceruloplasmin were observed by an enzyme-linked immunsorbent assay. Conclusion: These results suggest that the patients with RA and CP may exhibit three serum proteins with different abundance when compared with the patients with RA only, those with CP only, and the healthy controls.
    Journal of Periodontology 05/2013; · 2.40 Impact Factor
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    ABSTRACT: Background: Overproduction of interleukin-6 (IL-6) may play a pathological role in rheumatoid arthritis (RA) and chronic periodontitis (CP). The present study was undertaken to assess IL-6 receptor (IL-6R) inhibition therapy on periodontal condition in the patients with RA and CP. Methods: The study participants consisted of 28 and 27 patients with RA and CP during the treatment with and without IL-6R inhibitor (anti-IL-6R and control groups), respectively. After the medication of IL-6R inhibitor for 20.3 months on average, periodontal and rheumatologic parameters and serum levels of cytokine and inflammatory markers and immunoglobulin G to periodontopathic bacteria were examined at initial point (T1) and 8 weeks later (T2). Results: No differences were observed between the groups in any parameter values at T1, except for serum IL-6 levels. The anti-IL-6R group showed significantly greater decrease in gingival index, bleeding on probing (BOP), probing depth (PD), clinical attachment level (CAL), and serum levels of IL-6 and matrix metalloproteinase-3 (MMP-3) from T1 to T2 than the control group (p < 0.05). A significant correlation was found between changes in serum anti-cyclic citrullinated peptide levels and those in PD and CAL in the anti-IL-6R group (p < 0.05), while both groups exhibited a significant association between changes in serum MMP-3 levels and those in BOP (p < 0.05). Conclusions: Changes in periodontal and serum parameter values were different between the patients with RA and CP during the treatment with and without IL-6R inhibitor.
    Journal of Periodontology 03/2013; · 2.40 Impact Factor
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    ABSTRACT: Many studies have reported an association between periodontal disease and preterm birth, although this remains controversial. Cytokines and antibodies produced to give resistance to infection can enter the bloodstream and cause preterm labor. We analyzed maternal genetic polymorphisms in various immunoregulatory genes that could affect both preterm birth and periodontitis. A total of 1099 women referred to the Department of Obstetrics and Gynecology, Niigata University Medical and Dental Hospital were candidates for participation, 424 of whom refused, and 553 were excluded. The final number of subjects was 122 (51 with preterm birth, 71 with term birth). Genomic DNA was isolated from venous blood, and 22 polymorphisms were determined: IL-1A, IL-1B, IL-1RN, IL-2, IL-4, IL-6, IL-10, TNFA, TNFRI, TNFRII, FcγRIIA, FcγRIIB, FcγRIIIA, FcγRIIIB, and FcαR. Within five days of labor, periodontal parameters were evaluated, and bacteria from subgingival plaque were detected using real-time PCR. There was no difference in the prevalence and degree of periodontitis between term and preterm births. Chi-squared tests showed that an age <33 years and FcαR(+56)T/C alleles were associated with preterm birth. Multiple logistic regression analysis represented a model with significant fitness in which four variables were associated with preterm birth: maternal age, number of Aggregatibacter actinomycetemcomitans, IL-6(-572)G/C, and FcαR(+56)T/C. In conclusion, there was no association between preterm birth and periodontitis in this study. A. actinomycetemcomitans, IL-6, and FcαR were suggested to be associated with preterm birth. Multiple logistic regression models with both genetic and environmental factors would be useful for evaluating susceptibility to preterm birth.
    Journal of Reproductive Immunology 02/2012; 93(2):94-101. · 2.34 Impact Factor
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    ABSTRACT: Methylation status of the cytokine genes may play a role in the pathogenesis of inflammatory diseases, such as rheumatoid arthritis (RA) and chronic periodontitis (CP). This study was undertaken to evaluate whether the DNA methylation profile of the interleukin-6 (IL-6) gene promoter was unique to individuals with RA and CP. The study participants consisted of 30 patients with RA, 30 patients with CP, and 30 age-, sex-, and smoking status-balanced healthy controls. Genomic DNA isolated from peripheral blood was modified by sodium bisulfite and analyzed for DNA methylation levels of IL-6 gene with direct sequencing. Levels of IL-6 were determined by an enzyme-linked immunosorbent assay. The region of IL-6 gene promoter from -1200 to +27 bp was shown to contain 19 CpG motifs. The methylation levels of the CpG motif at -74 bp were significantly lower in patients with RA and CP than those in controls (P = 0.0001). Both levels of serum IL-6 and IL-6 production by mononuclear cells were significantly different between individuals with and without the methylation at -74 bp (P = 0.03). The +19 bp motif exhibited differential levels of the methylation among the groups, which was not associated with serum levels of IL-6. The other 17 CpG motifs exhibited comparable levels of the methylation between the groups. These results suggest that hypomethylated status of a single CpG in the IL-6 promoter region may lead to increased levels of serum IL-6, implicating a role in the pathogenesis of RA and CP.
    Journal of Periodontology 11/2011; 83(7):917-25. · 2.40 Impact Factor
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    ABSTRACT: Periodontopathic bacteria have been implicated as contributory to the etiology of rheumatoid arthritis (RA). Anticyclic citrullinated peptide (CCP) antibodies and rheumatoid factor (RF) were shown to be associated with RA. This study examines whether serum levels of antibodies to periodontopathic bacteria may affect clinical and laboratory profiles of RA. The study participants consisted of 80 patients with RA, and 38 age-, sex-, smoking status-, and periodontal condition-balanced healthy controls. After periodontal and rheumatologic examination, serum levels of immunoglobulin G (IgG) antibodies to Porphyromonas gingivalis (Pg), Prevotella intermedia, Aggregatibacter actinomycetemcomitans (Aa) (previously Actinobacillus actinomycetemcomitans), and Eikenella corrodens (Ec) and those of anti-CCP antibodies and RF were determined by an enzyme-linked immunosorbent assay. Patients with RA showed significantly higher levels of anti-Pg and anti-CCP antibodies than controls (P = 0.04 and P <0.0001). In contrast, IgG responses to Aa and Ec in patients with RA were significantly lower than those in controls (P <0.0001 and P = 0.0001). Multiple logistic regression analysis revealed a significant association of anti-Pg and anti-Aa IgG responses with RA, after adjustment for age, sex, and smoking (P = 0.005 and P = 0.02). Anti-Pg titer displayed a significant correlation with RF levels, probing depth, and clinical attachment level (P = 0.03, P = 0.03, and P = 0.02). These results suggest that serum levels of anti-Pg IgG antibodies were associated with RA, and might affect serum levels of RF and periodontal condition in patients with RA.
    Journal of Periodontology 02/2011; 82(10):1433-41. · 2.40 Impact Factor
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    ABSTRACT: This study was undertaken to evaluate the effect of oral administration of lactoferrin (LF) and lactoperoxidase-(LPO-)containing tablet on periodontal condition. Seventy-two individuals with chronic periodontitis were randomly assigned to take either bovine LF and LPO-containing tablets (test group, n = 37) or control tablets (control group, n = 35) every day for 12 weeks. Periodontal parameters and levels of subgingival plaque bacteria, human and bovine LF, and endotoxin in gingival crevicular fluid (GCF) were evaluated at baseline, 1 week, 4 weeks, and 12 weeks. Significant differences were observed in GCF levels of bovine LF between the test and control groups throughout the study (P < .05). However, clinical and bacteriological parameter values proved comparable between the two groups at 1 week to 12 weeks. Therefore, the effect of oral administration of LF and LPO-containing tablets might be weak on periodontal and bacteriological profile in this study.
    International Journal of Dentistry 01/2011; 2011:405139.
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    ABSTRACT: Rheumatoid arthritis (RA) and periodontitis are common chronic inflammatory conditions and share many pathologic features. A similar profile of cytokines is involved in the pathogenesis of the two diseases. The relationship between the disease activity of RA and the periodontal condition remains unclear. This study examines whether the disease activity of RA affects serum cytokine and periodontal profiles. The study subjects consisted of 84 Japanese adults with RA and 22 race-matched control individuals. After periodontal and rheumatologic examination, the disease activity of RA was determined with the Disease Activity Score including 28 joints using C-reactive protein (DAS28-CRP). Serum levels of cytokines including interleukin (IL)-1beta, IL-6, IL-12, IL-12 p40, IL-18, and tumor necrosis factor-alpha (TNF-alpha) were determined by an enzyme-linked immunosorbent assay. High-sensitive CRP was also measured with a latex particle-enhanced nephelometric method. Of 84 patients with RA, 28 and 56 patients exhibited low and moderate to high disease activity, respectively. Serum levels of IL-6, TNF-alpha, and CRP were significantly different between the two groups (P <0.05). Additionally, a significant correlation was observed between DAS28-CRP and percentage of sites with bleeding on probing (BOP) (P = 0.008) and between serum TNF-alpha levels and percentage of sites with BOP (P = 0.01) in 56 patients with RA with moderate to high activity. These results suggest that the disease activity of RA correlated with serum levels of IL-6, TNF-alpha, and CRP, and it might influence BOP in the patients with moderate to high disease activity.
    Journal of Periodontology 05/2010; 81(5):650-7. · 2.40 Impact Factor
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    ABSTRACT: Lactoferrin (LF) is a component of saliva and is suspected to be a defense factor against oral pathogens including Streptococcus mutans and Candida albicans. Periodontitis is a very common oral disease caused by periodontopathic bacteria. Antimicrobial activities and other biological effects of LF against representative periodontopathic bacteria, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia, have been widely studied. Association of polymorphisms in LF with incidence of aggressive periodontitis and the role of LF in the gingival crevicular fluid as a marker of periodontitis severity have also been reported. Periodontopathic bacteria reside as a biofilm in supragingival and subgingival plaque. Our recent study indicated that LF exhibits antibacterial activity against planktonic forms of P. gingivalis and P. intermedia at higher concentrations, and furthermore, LF effectively inhibits biofilm formation and reduces the established biofilm of these bacteria at physiological concentrations. A small-scale clinical study indicated that oral administration of bovine LF reduces P. gingivalis and P. intermedia in the subgingival plaque of chronic periodontitis patients. LF seems to be a biofilm inhibitor of periodontopathic bacteria in vitro and in vivo.
    Biology of Metals 02/2010; 23(3):419-24. · 3.17 Impact Factor
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    ABSTRACT: Lactoferrin (LF) is an iron-binding antimicrobial protein present in saliva and gingival crevicular fluids, and it is possibly associated with host defense against oral pathogens, including periodontopathic bacteria. In the present study, we evaluated the in vitro effects of LF-related agents on the growth and biofilm formation of two periodontopathic bacteria, Porphyromonas gingivalis and Prevotella intermedia, which reside as biofilms in the subgingival plaque. The planktonic growth of P. gingivalis and P. intermedia was suppressed for up to 5 h by incubation with >or=130 microg/ml of human LF (hLF), iron-free and iron-saturated bovine LF (apo-bLF and holo-bLF, respectively), and >or=6 microg/ml of bLF-derived antimicrobial peptide lactoferricin B (LFcin B); but those effects were weak after 8 h. The biofilm formation of P. gingivalis and P. intermedia over 24 h was effectively inhibited by lower concentrations (>or=8 microg/ml) of various iron-bound forms (the apo, native, and holo forms) of bLF and hLF but not LFcin B. A preformed biofilm of P. gingivalis and P. intermedia was also reduced by incubation with various iron-bound bLFs, hLF, and LFcin B for 5 h. In an examination of the effectiveness of native bLF when it was used in combination with four antibiotics, it was found that treatment with ciprofloxacin, clarithromycin, and minocycline in combination with native bLF for 24 h reduced the amount of a preformed biofilm of P. gingivalis compared with the level of reduction achieved with each agent alone. These results demonstrate the antibiofilm activity of LF with lower iron dependency against P. gingivalis and P. intermedia and the potential usefulness of LF for the prevention and treatment of periodontal diseases and as adjunct therapy for periodontal diseases.
    Antimicrobial Agents and Chemotherapy 06/2009; 53(8):3308-16. · 4.57 Impact Factor
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    ABSTRACT: Cytokines play a major role in the pathogenesis of rheumatoid arthritis (RA) and periodontitis. Both diseases were previously shown to be partly influenced by cytokine gene polymorphisms. Therefore, we evaluated whether the distributions of the cytokine genotypes were unique to subjects with both diseases. The study subjects consisted of Japanese adults with RA (RA group; n = 153), periodontitis only (P group; n = 117), and healthy individuals (H group; n = 108). Clinical periodontal condition was defined by measurements of probing depth, clinical attachment level, and bleeding on probing. Genomic DNA was isolated from peripheral blood and analyzed for the determination of 16 gene polymorphisms encoding interleukin (IL)-1, -2, -4, -6, and -10, tumor necrosis factor-alpha, and transforming growth factor-beta 1. The frequency of patients with RA who exhibited periodontitis was 89.5% (RA + P group; n = 137). No significant differences were observed in any of the frequencies of cytokine genotypes and alleles among the subject groups. After adjustment for age, gender, and smoking status, multiple logistic regression analysis revealed a significant difference in the distribution of IL-1B +3954 genotypes between RA + P and P groups (P = 0.006) and between RA + P and H groups (P = 0.008). Japanese individuals with RA and periodontitis may exhibit different distributions of IL-1B +3954 genotypes than healthy controls and subjects with periodontitis only.
    Journal of Periodontology 06/2009; 80(5):792-9. · 2.40 Impact Factor
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    ABSTRACT: A genome-association study is a powerful tool for analyzing small gene effects in complex diseases such as chronic periodontitis (CP), although the cost of analysis is prohibitive. We designed a study using the DNA pooling method, which could be a breakthrough in lowering such costs. This study was conducted to assess the genetic association in severe CP in a Japanese population. We adopted a DNA pooling method by genotyping 454 densely spaced microsatellite (MS) markers in chromosome 19 as a pilot study, with the possibility of future use in a whole-genome study. This can reduce the high cost and technical burden, which is generally unavoidable in a genomic association study. Pooled DNA samples from 300 case subjects, 300 control subjects, and 200 systemically healthy subjects were screened by genotyping MS markers. The case-control association in the candidate region was analyzed by individual typing of MS and single nucleotide polymorphisms (SNPs). The single MS marker allele 17 of 1902G31 was isolated in association with severe CP (P = 0.0012 for 2 x 2; P <0.046 for 2 x m, where m refers to the number of polymorphic alleles observed in a population). No other SNP or MS polymorphism hypothesized to affect biologic functions in the critical region was found in the linkage disequilibrium block analysis. We efficiently isolated the susceptible locus for severe CP in chromosome 19 and identified a useful marker to evaluate the risk for disease. This approach can be applied to a whole-genome study in severe CP.
    Journal of Periodontology 05/2009; 80(4):663-71. · 2.40 Impact Factor
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    ABSTRACT: Mannose binding lectin (MBL) is a key molecule in first line defense against various microorganisms. Polymorphism of the MBL gene greatly affects serum MBL concentration, and is known to be associated with occurrence of infectious diseases. We aimed to determine whether there is a relationship between occurrence or severity of chronic periodontitis (CP) and polymorphism of the MBL gene. Ninety-eight CP patients and 63 healthy subjects with no periodontitis were typed for the codon 54 polymorphism of the MBL gene by PCR-restriction fragment length polymorphism method. Genotype frequencies of the codon 54 polymorphism were similar between patients and control subjects. When patients were categorized to mild, moderate and severe periodontitis groups, possession of the low serum MBL concentration allele was a risk factor for having severe CP, as assessed by logistic regression analysis. Patients with MBL genotypes that cause lower serum MBL concentration may be at risk of having severe periodontitis. MBL gene typing may become useful to predict the prognosis of CP.
    Japanese Journal of Clinical Immunology 03/2009; 32(1):48-52.
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    ABSTRACT: The balance between the degradation and synthesis of extracellular matrix determines periodontal attachment levels and alveolar bone matrix concentration in periodontal diseases. Matrix metalloproteinases (MMPs) are known to degrade periodontal ligamental attachment and bone matrix proteins. The purpose of this study was to examine the effect of different expression levels of MMPs and their inhibitors, the tissue inhibitors of matrix metalloproteinases (TIMPs), in periodontitis. Sixteen inflamed gingival tissue samples from subjects with generalized chronic periodontitis and 14 control tissue samples from systemically and periodontally healthy subjects were evaluated. The total RNA was extracted, and the transcript levels for MMP-1, -3, -9, and -13 and TIMP-1, -2, -3, and -4 relative to beta-actin were determined by quantitative real-time reverse transcription-polymerase chain reaction. Gene transcript levels for MMP-1 and TIMP-4 were significantly higher in periodontitis-affected gingival tissues (P <0.05). MMP-3, -9, and -13 and TIMP-1 mRNAs also were elevated in periodontitis; however, the difference was not statistically significant. TIMP-2 and -3 mRNA levels were similar in healthy and diseased gingivae. The ratios of MMP-1/TIMP-2 (P <0.01), MMP-3/TIMP-2 (P <0.05), MMP-9/TIMP-2 (P <0.05), and MMP-1/TIMP-3 (P <0.01) from periodontitis lesions were significantly higher than those in the control tissues. Upregulated MMP expression and an increased MMP/TIMP ratio indicate that a potential imbalance between degradation and synthesis of extracellular matrix persists in periodontitis-affected gingival tissues. This process may be responsible for increased tissue breakdown in periodontitis.
    Journal of Periodontology 01/2008; 79(1):166-73. · 2.40 Impact Factor
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    ABSTRACT: The pathobiology of rheumatoid arthritis (RA) is similar to that of periodontitis in that proinflammatory cytokines and immunoglobulin G Fc receptor (FcgammaR) play an important role. Functional polymorphisms of interleukin (IL)-1 and FcgammaR were shown to be associated with susceptibility to both diseases. Therefore, we evaluated whether the IL-1 and FcgammaR gene polymorphisms represent a common risk factor for RA and periodontitis. The study population consisted of Japanese adults with RA (RA group; N = 100), periodontitis only (P group; N = 100), and healthy individuals with no systemic or oral disease (H group; N = 100). Clinical periodontal condition was defined by measurements of probing depth, clinical attachment level, and bleeding on probing. Genomic DNA was isolated from peripheral blood and analyzed for determination of IL-1 genotypes (IL-1A+4845, IL-1B+3954, and IL-1RN+2028) and FcgammaR genotypes (FcgammaRIIA, FcgammaRIIIA, and FcgammaRIIIB) by allele-specific polymerase chain reactions. Among 100 patients with RA, 86% showed periodontal tissue destruction. However, the RA group exhibited milder levels of periodontal tissue destruction than the P group (P <0.01). There was a significant difference in the distribution of IL-1B+3954 C/T genotypes between the RA and P groups and between the RA and H groups (P = 0.03 for both comparisons), with enrichment of the T allele in the RA group (P = 0.04; odds ratio, 2.9 for both comparisons). The combination of IL-1A+4845 T and IL-1+3954 T alleles yielded a strong association with RA and periodontitis (RA versus P group: P = 0.00001; RA versus H group: P = 0.00001). These results failed to show that IL-1 and FcgammaR gene polymorphisms constitute a common risk factor for RA and periodontitis. However, it was suggested that the distributions of IL-1B+3954 genotypes and IL-1A+4845 and IL-1B+3954 haplotypes were unique to the patients with RA and periodontitis.
    Journal of Periodontology 12/2007; 78(12):2311-8. · 2.40 Impact Factor
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    ABSTRACT: 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 recently reported the construction and characterization of human immunoglobulin G isotype clones, which were specifically reactive with recombinant (r) 40-kDa outer membrane protein (OMP) of P. gingivalis. The aim of this study was to investigate the efficacy of human monoclonal antibody (hMAb) against r40-kDa OMP of P. gingivalis to the protection alveolar bone loss by P. gingivalis in rats. The role of 40-kDa OMP in the adherence of P. gingivalis to human gingival epithelial cells (HGECs) was examined by preincubating with r40-kDa OMP hMAb before adding the HGECs. Moreover, we used a rat model to examine the effect of the anti-r40-kDa OMP hMAb in alveolar bone loss by oral infection. Forty-six days after the last infection, the periodontal bone level was assessed morphometrically on defleshed rat jaws. The adherence to HGECs was reduced by 84% compared to adherence levels without the antibody. P. gingivalis could not be detected from rats in a P. gingivalis-non-infected group and a group that was administered the anti-r40-kDa OMP hMAb. The bone loss in P. gingivalis-infected animals that were administered the anti-r40-kDa OMP hMAb was significantly lower than that of P. gingivalis-infected rats. Our results suggest that transchromosomic mouse-derived hMAb against r40-kDa OMP of P. gingivalis protects against periodontal bone loss. This newly constructed anti-r40-kDa OMP hMAb was used to protect against periodontal diseases caused by P. gingivalis infection.
    Journal of Periodontology 06/2007; 78(5):933-9. · 2.40 Impact Factor
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    ABSTRACT: The pathobiology of systemic lupus erythematosus (SLE) is similar to that of periodontitis in that the immunoglobulin G Fc receptor (FcgammaR) and proinflammatory cytokines play an important role. Genetic variations of FcgammaR and interleukin (IL)-1 are associated with susceptibility to both diseases. Therefore, we evaluated whether the combination of FcgammaR or IL-1 polymorphic genes represents a common risk factor for SLE and periodontitis. The study population consisted of Japanese adults with SLE and periodontitis (SLE+P group; n = 46), SLE only (SLE group; n = 25), periodontitis only (P group; n = 58), and healthy individuals with no systemic or oral disease (H group; n = 44). Clinical periodontal condition was evaluated by measurement of probing depth, clinical attachment level, and alveolar bone loss. Genomic DNA was isolated from peripheral blood and analyzed for determination of FcgammaR genotypes (FcgammaRIIA, FcgammaRIIB, FcgammaRIIIA, and FcgammaRIIIB) and IL-1 genotypes (IL-1A +4845 and IL-1B +3954) by allele-specific polymerase chain reactions or DNA sequencing. A significant overrepresentation of the R131 allele of stimulatory FcgammaRIIA and the 232T allele of inhibitory FcgammaRIIB was found in the SLE+P group compared to the H group (P = 0.01 and P = 0.0009, respectively). The combination of FcgammaRIIA-R131 and FcgammaRIIB-232T alleles yielded a strong association with SLE and periodontitis (SLE+P group versus P group: P = 0.01, odds ratio: 3.3; SLE+P group versus H group: P = 0.0009, odds ratio: 11.2). Furthermore, SLE patients with the combined FcgammaR risk alleles exhibited more severe periodontal tissue destruction compared to other SLE patients. The frequencies of IL-1 polymorphic alleles were too low to assess the association with SLE or periodontitis. The combination of stimulatory FcgammaRIIA and inhibitory FcgammaRIIB genotypes may increase susceptibility to SLE and periodontitis in the Japanese population.
    Journal of Periodontology 04/2007; 78(3):467-74. · 2.40 Impact Factor
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    ABSTRACT: Saliva has been used as a diagnostic fluid in medicine and dentistry. It is easy to collect using non-invasive methods. The intracellular enzymes present in saliva have been studied as markers of periodontal disease. The purpose of this study was to determine the salivary enzyme levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) after scaling and to clarify the influence of interleukin (IL)-1 genotypes on these enzyme levels. Forty-nine Japanese patients with chronic periodontitis (24 men and 25 women; mean age: 55.1 years) were enrolled in this study. Measurements of clinical parameters including probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP) and collections of stimulated whole mixed saliva were performed at baseline and 4 weeks after scaling. After evaluation of salivary AST, ALT, and LDH levels, DNA was extracted from various cells in whole saliva. IL-1A+4845 G/T genotype was determined by polymerase chain reaction amplification, followed by enzyme digestion and electrophoresis. Statistical analysis was performed by the Wilcoxon signed-rank and Mann-Whitney U tests. A significant difference was set at P <0.05. Mean PD, CAL, and BOP values significantly decreased after scaling (mean +/- SE: 3.2 +/- 0.1 mm to 2.6 +/- 0.1 mm in PD; 3.9 +/- 0.2 mm to 3.3 +/- 0.2 mm in CAL; and 41% +/- 4% to 18% +/- 3% in BOP) (P <0.001). The values of AST, ALT, and LDH were 77.0 +/- 7.5, 43.9 +/- 5.5, and 753.4 +/- 96.5 (units per liter [U/l]) at baseline, and significantly decreased to 55.5 +/- 6.5, 30.0 +/- 5.5, and 394.7 +/- 34.0 (U/l) after scaling, respectively (P = 0.01, P = 0.006, and P <0.001). The carriage rate of the IL-1A+4845 allele 2 was 24.5%. No difference was noted in the decrease in PD, CAL, and BOP after scaling between the carriers (N = 12) and non-carriers (N = 37) of IL-1A+4845 allele 2. However, the IL-1A allele 2 non-carriers displayed a significant decrease in salivary AST and ALT levels (P <0.001), in contrast to the carriers who did not show any changes in the salivary levels of the enzymes after scaling. These results documented that salivary AST, ALT, and LDH levels reflect inflammation and destruction of periodontal tissue, suggesting clinically useful markers following periodontal therapy. In addition, although IL-1A+4845 alleles may not influence clinical parameters, they may influence post-scaling values of salivary AST and ALT.
    Journal of Periodontology 03/2007; 78(3):498-503. · 2.40 Impact Factor
  • Periodontology 2000 02/2007; 43:102-32. · 4.01 Impact Factor

Publication Stats

523 Citations
73.42 Total Impact Points

Institutions

  • 2002–2012
    • Niigata University
      • • Division of Periodontology
      • • Division of General Dentistry and Clinical Education
      • • Center for Transdisciplinary Research
      • • Department of Oral Biological Science
      • • Division of Preventive Dentistry
      Niahi-niigata, Niigata, Japan
  • 2009–2010
    • Morinaga Milk Industry Co., Ltd.
      Edo, Tōkyō, Japan