Microbiological and Clinical Effects of Sitafloxacin and Azithromycin in Periodontitis Patients Receiving Supportive Periodontal Therapy.

Sitafloxacin (STFX) is a newly developed quinolone that has robust antimicrobial activity against periodontopathic bacteria. We previously reported that oral administration of STFX during supportive periodontal therapy was as effective as conventional mechanical debridement under local anesthesia microbiologically and clinically for 3 months. The aim of the present study was to examine the short-term and long-term microbiological and clinical effects of systemic STFX and azithromycin (AZM) on active periodontal pockets during supportive periodontal therapy. Fifty-one patients receiving supportive periodontal therapy were randomly allocated to the STFX group (200 mg/day of STFX for 5 days) or the AZM group (500 mg/day of AZM for 3 days). The microbiological and clinical parameters were examined until 12 months after the systemic administration of each drug. The concentration of each drug in periodontal pockets and the antimicrobial susceptibility of clinical isolates were also analyzed. The proportions of red complex bacteria, i.e., Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia, which are the representative periodontopathic bacteria, were significantly reduced at 1 month and remained lower at 12 months than those at baseline in both the STFX and AZM groups. Clinical parameters were significantly improved over the 12-month period in both groups. An increase in the MIC of AZM against clinical isolates was observed in the AZM group. These results indicate that monotherapy with systemic STFX and AZM might be an alternative treatment during supportive periodontal therapy in patients for whom invasive mechanical treatment is inappropriate. (This study has been registered with the University Hospital Medical Information Network-Clinical Trials Registry [UMIN-CTR] under registration number UMIN000007834.).

Effects of systemic sitafloxacin on periodontal infection control in elderly patients.

OBJECTIVE: To evaluate the microbiological and clinical effects of the systemic administration of sitafloxacin (STFX) on periodontal pockets in elderly patients receiving supportive periodontal therapy (SPT). BACKGROUND: Periodontitis is a risk factor for atherosclerosis. Better periodontal health contributes to reduce atherosclerosis-related diseases in elderly population. MATERIALS AND METHODS: Forty-four patients undergoing SPT were randomly assigned to two groups: a test group took 100 mg/day of STFX for five consecutive days, or a control group received scaling and root planing (SRP) under local anaesthesia. Microbiological and clinical parameters were examined at baseline and at 1 and 3 months after therapy. RESULTS: The presence of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia was significantly reduced at 1 month after treatment in both groups. The median reductions of the bacteria between the baseline and 1 month were 3.08 and 2.54% in the STFX- and SRP-treated groups, respectively. Both treatments significantly decreased the probing depth at 1 and 3 months compared to the baseline. CONCLUSION: The systemic administration of STFX is effective at improving periodontal health during SPT and could be an alternative to SRP for elderly patients who cannot undergo anaesthesia or are at risk of tissue injury.

Increased serum PCSK9 concentrations are associated with periodontal infection but do not correlate with LDL cholesterol concentration.

BACKGROUND: Periodontal disease increases the risk of atherothrombotic disease, and high concentrations of low density lipoprotein (LDL) cholesterol are considered to be involved; however, the underlying mechanisms are largely unknown. Recent studies demonstrated that proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a critical role in circulating LDL cholesterol concentrations. The aim of the present study is to analyze serum PCSK9 concentrations and their relation to lipoprotein concentrations in periodontitis patients. METHODS: Sera were obtained from 40 periodontitis patients and 30 control subjects. PCSK9 concentrations, high-sensitivity C-reactive protein (hs-CRP), IL-6, TNF-α and Porphyromonas gingivalis antibodies were measured by ELISA, and lipid profiles were determined by a commercial laboratory. RESULTS: Periodontitis patients demonstrated significantly higher serum antibody titer to P. gingivalis and hs-CRP concentrations than control subjects, suggesting infection with P. gingivalis and a systemic inflammatory response. PCSK9 concentrations in periodontitis patients were significantly higher than those in control subjects. However, the concentrations of total and LDL cholesterols were not significantly different between periodontitis patients and control subjects. Moreover, no correlations were observed between PCSK9 concentrations and lipid profiles. CONCLUSION: Periodontal infection upregulates PCSK9 production. However, further studies are required to elucidate how periodontal infection affects PCSK9 concentrations and subsequent lipid metabolism.

Effect of interleukin-17 on the expression of chemokines in gingival epithelial cells.

The role of interleukin (IL)-17 in cellular communication in inflammation has been well described, and a positive correlation between the severity of periodontitis and the level of IL-17 was reported. Although epithelial cells are a major target of IL-17, little is known about the effect of IL-17 on the production of chemokines by human gingival epithelial cells (HGECs). We evaluated the effects of IL-17 on the expression of CXCL8 and CCL2 by HGECs using quantitative real-time PCR and ELISA. In addition, the role of the nuclear factor (NF)-κB signalling pathway in the IL-17-mediated expression of chemokines was assessed using a specific inhibitor. Stimulation with IL-17 up-regulated the expression of CXCL8 mRNA but not of CCL2 mRNA in HGECs, whereas tumour necrosis factor-α (TNF-α) elevated the expression of mRNA for both chemokines. Stimulation with IL-17 up-regulated the secretion of CXCL8 protein, but not the secretion of CCL2 protein. The effect of IL-17 on CXCL8 production was suppressed using an anti-IL-17R Ig, suggesting a role for a specific receptor-ligand interaction. Inhibition of the NF-κB signalling pathway demonstrated that NF-κB activation is required for the CXCL8 expression in HGECs. In conclusion, IL-17 is involved in the regulation of the innate immune response in HGECs by inducing CXCL8 production.

Elevated antibody titers to Porphyromonas gingivalis as a possible predictor of ischemic vascular disease - results from the Tokamachi-Nakasato cohort study.

AIM: Limited epidemiological studies have investigated the relationship between ischemic vascular disease and periodontitis in non-Western populations. We investigated this relationship in a Japanese cohort by measuring serum titers of antibodies to periodontopathic bacteria. METHODS: As part of the Tokamachi-Nakasato cohort study, we followed up 7021 participants regarding cardiovascular events over 5 years, and observed 99 ischemic vascular events: 66 cerebral infarctions and 33 cases of ischemic heart disease (IHD). For a nested case-control study, we selected 495 sex- and age-matched control subjects. Conditional logistic regression analysis was used to estimate the odds ratios (OR) and 95% confidence intervals (CI) of ischemic vascular events associated with antibody titers to Porphyromonas gingivalis FDC381 and SU63. Multivariable models were adjusted for traditional cardiovascular risk factors using propensity scores. RESULTS: The highest tertile category of antibody titers to P. gingivalis FDC381 in men was significantly associated with an increased risk of cerebral infarction in only the crude model. The 2nd and 3rd tertile categories of antibody titers to P. gingivalis SU63 were significantly associated with an increased risk of cerebral infarction in men (multivariable ORs (95% CIs) were 7.12 (1.51-33.5) and 9.03 (1.97-41.5), respectively). The association was not appreciably modified when we further adjusted for serum high-sensitivity C-reactive protein levels. Antibody titers to P. gingivalis were not dose-dependently associated with the risk of IHD. CONCLUSION: High serum antibody titers to P. gingivalis SU63 could be a predictor of cerebral infarction in Japanese men independent of traditional risk factors and inflammation.

Porphyromonas gingivalis antigens and interleukin-6 stimulate the production of monocyte chemoattractant protein-1 via the upregulation of early growth response-1 transcription in human coronary artery endothelial cells.

BACKGROUND: Individuals with periodontitis have elevated serum levels of IL-6 and C-reactive protein and have been reported to have a significantly increased risk of developing cardiovascular disease. The transcription factor early growth response factor 1 (Egr-1) has been shown to play an important role in the development and progression of atherosclerosis. However, it is not known whether periodontal infection affects the expression of Egr-1 and subsequent endothelial cells expression of monocyte chemoattractant protein (MCP)-1, a key molecule of leukocyte chemoattraction into vessels. METHODS: Human coronary artery endothelial cells (HCAECs) were stimulated with either sonicated extracts from Porphyromonas gingivalis strains 381 or SU63, or a combination of IL-6 and soluble IL-6 receptor (IL-6/sIL-6R). The expression of Egr-1, and subsequently MCP-1, was then analyzed. The role of Egr-1 on MCP-1 expression was analyzed by siRNA transfection. RESULTS: Both P. gingivalis antigens and IL-6/sIL-6R stimulations upregulated the expression of Egr-1, with a more robust effect by IL-6/sIL-6R. Increased expression of Egr-1 coincided with MCP-1 production, and Egr-1 downregulation by siRNA suppressed this effect. CONCLUSION: These results clearly suggest that periodontal infection has the potential to affect HCAECs and hence contribute to the development of subsequent atherosclerosis.

Elevated expression of IL-17 and IL-12 genes in chronic inflammatory periodontal disease.

BACKGROUND: A number of different theories have been postulated to explain the progression of gingivitis to periodontitis in the context of the Th1/Th2 paradigm. However, no consistent results have been obtained. Th17, a new T-cell subset producing IL-17, which is implicated in many aspect of inflammatory tissue destruction, overcomes many of the discrepant findings in the studies related to the Th1/Th2 hypothesis. We compared the gene expression profile of Th17-related molecules in gingivitis and periodontitis lesions showing distinct clinical entities. METHODS: Gingival tissue samples were obtained from 23 gingivitis and 24 periodontitis tissues. The gene expression was measured by using quantitative real-time PCR for IL-17A, IL-17F, CCR4, CCR6, IL-12 p35 and IL-23 p19. The difference of gene expressions between gingivitis and periodontitis was analyzed by Mann-Whitney U-test. Correlations between each gene expression were also analyzed. RESULTS: The expression level of IL-17A was higher than that of IL-17F and a significant difference in expression between gingivitis and periodontitis was observed only for IL-17A. CCR4 and CCR6 tended to be higher in periodontitis compared with gingivitis, although the differences were not statistically significant. Whereas the gene expression of IL-12 p35 was significantly higher in periodontitis compared with gingivitis, that of IL-23 p19 was not different between the two diseases. CONCLUSION: This study demonstrates the elevated expression of IL-17 and IL-12 in periodontitis, i.e., the tissue destruction form of periodontal diseases, as compared with gingivitis, and provides new insight into the T-cell mediated immunopathogenesis of periodontal disease.