Soluble Cell Adhesion Molecules in Gingival Crevicular Fluid in Periodontal Health and Disease

Neuroinflammation related to the blood-brain barrier and sphingosine-1-phosphate in a pre-clinical model of periodontal diseases and depression in rats

AIM

To explore the potential mechanisms of neuroinflammation (microglia, blood-brain barrier [BBB] permeability, and the sphingosine-1-phosphate [S1P] pathways) resulting from the association between periodontitis and depression in rats.

MATERIALS AND METHODS

This pre-clinical in vivo experimental study used Wistar rats, in which experimental periodontitis (P) was induced by using oral gavages with Porphyromonas gingivalis and Fusobacterium nucleatum. Then, a chronic mild stress (CMS) model was implemented to induce a depressive-like behaviour, resulting in four groups: P with CMS (P+CMS+), P without CMS (P+CMS-), CMS without P (P-CMS+), and control (P-CMS-). After harvesting brain samples, protein/mRNA expression analyses and fluorescence immunohistochemistry were performed in the frontal cortex (FC). Results were analysed by ANOVA.

RESULTS

CMS exposure increased the number of microglia (an indicator of neuroinflammation) in the FC. In the combined model (P+CMS+), there was a decrease in the expression of tight junction proteins (zonula occludens-1 [ZO-1], occludin) and an increase in intercellular and vascular cell adhesion molecules (ICAM-1, VCAM-1) and matrix metalloproteinase 9 (MMP9), suggesting a more severe disruption of the BBB. The enzymes and receptors of S1P were also differentially regulated.

CONCLUSIONS

Microglia, BBB permeability, and S1P pathways could be relevant mechanisms explaining the association between periodontitis and depression.

Identification of IL-18 and Soluble Cell Adhesion Molecules in the Gingival Crevicular Fluid as Novel Biomarkers of Psoriasis

Psoriasis is a chronic immunoinflammatory skin disease. Although its diagnosis is clinical, differences in the appearance and severity of lesions pose a challenge for clinicians worldwide. The use of accessible biomarkers for psoriasis could aid in the early diagnosis and treatment of the disease. To date, evidence on the analysis of gingival crevicular fluid (GCF) molecules as novel, accessible, and reliable biomarkers for psoriasis is limited. This cross-sectional study compared the GCF levels of IL-18, soluble (s)ICAM-1, and sE-selectin in psoriatic patients (n = 42) and healthy controls (n = 39). Individuals with psoriasis not undergoing treatment and healthy individuals were included independent of periodontal status. GCF samples were collected, and a multiplex bead immunoassay was performed to quantify the levels of the target molecules. Psoriatic patients presented higher concentrations of IL-18 and lower concentrations of sE-selectin compared to controls (p < 0.05). No differences were found in the levels of sICAM-1 between the two groups (p > 0.05). Psoriasis was associated with IL-18 and E-selectin levels regardless of periodontal status, age, and smoking habit (p < 0.05). The areas under the receiver operating characteristic curve (ROC) for IL-18 and sE-selectin were 0.77 and 0.68, respectively. In conclusion, IL-18 and sE-selectin levels in the GCF could be promising biomarker for psoriasis.

Periodontal disease and incident venous thromboembolism: The Atherosclerosis Risk in Communities study

AIM

Periodontal disease is a cardiovascular disease (CVD) risk factor but few studies have considered the relationship between periodontal disease and venous thromboembolism (VTE). We hypothesized that periodontal disease is independently associated with increased risk of incident VTE.

MATERIALS AND METHODS

We used data from 8,092 participants of the Atherosclerosis Risk in Communities (ARIC) study to examine periodontal disease in 1996-1998 and incident VTE through 2011. Periodontal disease was determined using self-reported tooth loss due to gum disease and dental examinations. Cox proportional hazards regression models were used to estimate hazard ratios for VTE and 95% confidence intervals adjusted for relevant confounders.

RESULTS AND CONCLUSIONS

Participants were on average 62.7 years old at baseline and 13.9% self-reported tooth loss from gum disease. Over a mean of 12.9 years of follow-up, there were 313 incident VTE events. Self-reported tooth loss due to gum disease was associated with 30% higher VTE risk (HR = 1.29 (0.96, 1.73) after adjusting demographic factors, SES, periodontal risk factors, oral hygiene, and access to dental care variables. No statistically significant associations between clinical measures of periodontitis and VTE were observed after adjustment. Further research is needed to elucidate whether a relationship between periodontal disease and VTE exists.

The effect of periodontal therapy on neopterin and vascular cell adhesion molecule-1 levels in chronic periodontitis patients with and without acute myocardial infarction: a case-control study

The presence of neopterin in gingival crevicular fluid (GCF) is a marker for local and acute immune activation, and the presence of vascular cell adhesion molecule (VCAM-1) in GCF is accepted as a marker for chronic vascular inflammation.

Nonsurgical periodontal therapy with/without diode laser modulates metabolic control of type 2 diabetics with periodontitis: a randomized clinical trial

In order to evaluate whether nonsurgical periodontal treatment with/without diode laser (DL) decontamination improves clinical parameters, the levels of IL-1β, IL-6, IL-8, intercellular adhesion molecule (ICAM), and vascular cell adhesion molecule (VCAM) in gingival crevicular fluid and metabolic control (HbA1c) in chronic periodontitis (CP) patients with diabetes mellitus type 2 (DM2). Sixty patients with DM2 and CP were randomly assigned into two groups to receive scaling and root planing (SRP, n = 30) or SRP followed by diode laser application (SRP + DL, n = 30). Clinical periodontal and gingival crevicular fluid (GCF) parameters were assessed at baseline, 1, and 3 months after periodontal treatment. HbA1c levels were evaluated at baseline and 3 months post-therapy. Total amounts of cytokines and molecules were analyzed by ELISA. Nonsurgical periodontal treatment with/without DL appeared to improve clinical, biochemical parameters, and glycemic control in DM2 patients (BMI < 25 kg/m(2)) with CP. The SRP + DL group provided better reductions in probing depth (PD) and clinical attachment level (CAL) parameters compared to the SRP group (P < 0.05). Significant reductions were found in the total amounts of GCF levels of IL-1, IL-6, IL-8, ICAM, and VCAM after treatment (P < 0.05). HbA1c levels decreased significantly at 3 months after treatment (P < 0.05). SRP + DL reduced HbA1c levels more significantly compared to SRP alone (0.41 vs. 0.22 %, P < 0.05). SRP, especially in combination with DL, shows improvement of glycemic control for DM2 patients with CP.

Intracellular adhesion molecule-1 is regulated by porphyromonas gingivalis through nucleotide binding oligomerization domain-containing proteins 1 and 2 molecules in periodontal fibroblasts

BACKGROUND

The mechanism by which Porphyromonas gingivalis regulates intracellular adhesion molecule 1 (ICAM-1) expression in human periodontal ligament cells (hPDLCs) and human gingival fibroblasts (hGFs) is unknown. The aim of this study is to investigate whether nucleotide binding oligomerization domain-containing protein (NOD) 1 and NOD2 are involved in this process and the clinical significance of ICAM-1 in periodontitis.

METHODS

hPDLCs and hGFs were treated with P. gingivalis, l-Ala-γ-d-glutamyl-mesodiaminopimelic acid (an agonist for NOD1), and muramyl dipeptide (an agonist for NOD2). Alternatively, cells transfected with small interfering RNA targeting NOD1and NOD2 were treated with P. gingivalis. ICAM-1, NOD1, and NOD2 were detected at mRNA and protein levels. In addition, clinical examinations were performed in 30 healthy controls and 40 patients with chronic periodontitis (CP) before and after treatment, and serum-soluble ICAM-1 (sICAM-1) levels in these individuals were detected by enzyme-linked immunosorbent assay.

RESULTS

This study shows that P. gingivalis caused an increase in ICAM-1, NOD1, and NOD2 expression in periodontal fibroblasts. There was a linear correlation between ICAM-1 and NOD1 and NOD2 levels. Activation of NOD1 and NOD2 by the specific agonist led to the upregulation of ICAM-1, whereas knocking down NOD1 and NOD2 caused a reduction in P. gingivalis-induced ICAM-1 production. Furthermore, sICAM-1 levels were higher in patients with CP than in healthy controls and were positively related to the clinical periodontal parameters. After periodontal treatment, sICAM-1 levels decreased significantly.

CONCLUSIONS

The present results indicate that sICAM-1 levels are correlated to the severity of periodontitis. NOD1 and NOD2 mediate P. gingivalis-induced ICAM-1 production in periodontal fibroblasts. NOD1 and NOD2 could be considered potential targets for periodontal therapy.

Role of high endothelial postcapillary venules and selected adhesion molecules in periodontal diseases: a review

Periodontitis is accompanied by the proliferation of small blood vessels in the gingival lamina propria. Specialized postcapillary venules, termed periodontal high endothelial-like venules, are also present, and demonstrate morphological and functional traits similar to those of high endothelial venules (HEVs) in lymphatic organs. The suggested role of HEVs in the pathogenesis of chronic periodontitis involves participation in leukocyte transendothelial migration and therefore proinflammatory effects appear. Recent observations suggest that chronic periodontitis is an independent risk factor for systemic vascular disease and may result in stimulation of the synthesis of acute phase protein by cytokines released by periodontal high endothelial cells (HECs). However, tissue expression of HEV-linked adhesion molecules has not been evaluated in the gingiva of patients with chronic periodontitis. This is significant in relation to potential therapy targeting expression of the adhesion molecules. In this review, current knowledge of HEV structure and the related expression of four surface adhesion molecules of HECs [CD34, platelet endothelial cell adhesion molecule 1, endoglin and intercellular adhesion molecule 1 (ICAM-1)], involved in the key steps of the adhesion cascade in periodontal diseases, are discussed. Most studies on the expression of adhesion molecules in the development and progression of periodontal diseases pertain to ICAM-1 (CD54). Studies by the authors demonstrated quantitatively similar expression of three of four selected surface markers in gingival HEVs of patients with chronic periodontitis and in HEVs of reactive lymph nodes, confirming morphological and functional similarity of HEVs in pathologically altered tissues with those in lymphoid tissues.

Evaluation of PECAM-1 Gene Polymorphism in Patients with Periodontal Disease and Healthy Individuals

Objective. Our aim in this paper was to investigate the possible genetic association between three Ser563Asn, Leu125Val and Arg670Gly polymorphisms of the PECAM-1 gene and periodontitis. Methods. Genomic DNA was isolated from whole blood of 105 periodontal patient (52 with chronic periodontitis and 53 with aggressive periodontitis) and 101 healthy individuals. Samples were genotyped and analyzed for the three single-nucleotide polymorphisms (SNPs) of PECAM-1 using polymerase chain reaction with sequence-specific primers (PCR-SSPs). Results. A statistically significant difference was found between the genotypic distribution of the Ser563Asn polymorphism in patients with periodontitis compared to controls (P = 0.02). But there were no statistically significant difference between the allele frequencies in the different groups (P = 0.05). The other two polymorphisms did not show a statistically significant difference in their allele and genotype frequencies between the groups. There was no statistically significant difference found for any of the polymorphisms allele and genotype distribution in aggressive and chronic periodontitis either. Conclusions. No significant association was found between the polymorphism tested and the subgroups of periodontitis, further research is still necessary to determine whether this polymorphism can be used as a genetic marker of periodontitis.

Selectins and Associated Adhesion Proteins in Inflammatory disorders

Inflammation is defined as the normal response of living tissue to injury or infection. It is important to emphasize two components of this definition. First, that inflammation is a normal response and, as such, is expected to occur when tissue is damaged. Infact, if injured tissue does not exhibit signs of inflammation this would be considered abnormal and wounds and infections would never heal without inflammation. Secondly, inflammation occurs in living tissue, hence there is need for an adequate blood supply to the tissues in order to exhibit an inflammatory response. The inflammatory response may be triggered by mechanical injury, chemical toxins, and invasion by microorganisms, and hypersensitivity reactions. Three major events occur during the inflammatory response: the blood supply to the affected area is increased substantially, capillary permeability is increased, and leucocytes migrate from the capillary vessels into the surrounding interstitial spaces to the site of inflammation or injury. The inflammatory response represents a complex biological and biochemical process involving cells of the immune system and a plethora of biological mediators. Cell-to-cell communication molecules such as cytokines play an extremely important role in mediating the process of inflammation. Inflammation and platelet activation are critical phenomena in the setting of acute coronary syndromes. An extensive exposition of this complex phenomenon is beyond the scope of this article (Rankin 2004).

Tannerella forsythia infection-induced calvarial bone and soft tissue transcriptional profiles

Tannerella forsythia is associated with subgingival biofilms in adult periodontitis, although the molecular mechanisms contributing to chronic inflammation and loss of periodontal bone remain unclear. We examined changes in the host transcriptional profiles during a T. forsythia infection using a murine calvarial model of inflammation and bone resorption. Tannerella forsythia was injected into the subcutaneous soft tissue over calvariae of BALB/c mice for 3 days, after which the soft tissues and calvarial bones were excised. RNA was isolated and Murine GeneChip (Affymetrix, Santa Clara, CA) array analysis of transcript profiles showed that 3226 genes were differentially expressed in the infected soft tissues (P < 0.05) and 2586 genes were differentially transcribed in calvarial bones after infection. Quantitative real-time reverse transcription-polymerase chain reaction analysis of transcription levels of selected genes corresponded well with the microarray results. Biological pathways significantly impacted by T. forsythia infection in calvarial bone and soft tissue included leukocyte transendothelial migration, cell adhesion molecules (immune system), extracellular matrix-receptor interaction, adherens junction, and antigen processing and presentation. Histologic examination revealed intense inflammation and increased osteoclasts in calvariae compared with controls. In conclusion, localized T. forsythia infection differentially induces transcription of a broad array of host genes, and the profiles differ between inflamed soft tissues and calvarial bone.

Relationship between obesity and physical fitness and periodontitis

BACKGROUND

Obesity and exercise are important elements associated with lifestyle-related diseases, and studies suggested that these factors may also be related to periodontitis. This study investigates the relationship between obesity and physical fitness and periodontitis.

METHODS

One thousand, one hundred and sixty Japanese subjects, aged 20 to 77 years, who participated in health examinations at Fukuoka Health Promotion Center were analyzed. Periodontal conditions were evaluated using the Community Periodontal Index (CPI), and subjects with > or =3 sextants of CPI code 3 or 4 were defined as having severe periodontitis. We used the body mass index (BMI) and percentage of body fat as indicators of obesity and estimated the maximal oxygen consumption (VO(2max)) during exercise as an indicator of physical fitness. We divided these variables into quintiles. We examined the single effect and interactions of the obesity index and VO(2max) on severe periodontitis.

RESULTS

The lowest quintile in BMI and the highest quintile in VO(2max) were inversely associated with severe periodontitis, singly, in multivariate logistic regression analyses. Subjects with the combined lowest quintile in BMI and the highest quintile in VO(2max) had a significantly lower risk of severe periodontitis compared to subjects with other combined quintiles in BMI and in VO(2max) (odds ratio: 0.17; 95% confidence interval: 0.05 to 0.55).

CONCLUSION

This study suggests that obesity and physical fitness may have some interactive effect on periodontal health status.

Influence of periodontal therapy on the regulation of soluble cell adhesion molecule expression in aggressive periodontitis patients

BACKGROUND

Inflammatory periodontal disease is associated with an increased risk of cardiovascular disease. Circulating cell adhesion molecules (CAM) (intercellular adhesion molecule-1 [ICAM-1], vascular cell adhesion molecule-1 [VCAM-1], and E-selectin) have been suggested as potential candidate markers of endothelial dysfunction, which contribute to the pathogenesis of cardiovascular diseases. The regulation of CAM in subjects with severe periodontitis and the influence of periodontal intervention on systemic CAM levels are not clear. The aim of this study was to determine whether intensive periodontal therapy reduces serum levels of CAM in patients with generalized aggressive periodontitis.

METHODS

Blood samples were collected at six treatment time points from 21 patients with previously untreated generalized aggressive periodontitis (mean age: 34.6 +/- 4.3 years). Patients received subgingival scaling and root planing and antibiotic therapy and were monitored over a 6-month recall period. Serum levels of soluble ICAM-1 (sICAM-1), VCAM-1 (sVCAM-1), and E-selectin (sE-selectin) were measured by enzyme-linked immunosorbent assay.

RESULTS

sE-selectin plasma levels decreased significantly (P <0.01) during periodontal therapy. Mean plasma levels were 65.95 ng/ml before treatment and 44.71 ng/ml 6 months after antibiotic therapy. sICAM-1 and sVCAM-2 serum levels were unaffected by therapeutic intervention.

CONCLUSIONS

Periodontal therapy reduces plasma sE-selectin levels. Whether this leads to a reduction in risk of future cardiovascular events in patients with aggressive periodontal disease warrants further studies.

Oxidant/antioxidant interactions of nicotine, Coenzyme Q10, Pycnogenol and phytoestrogens in oral periosteal fibroblasts and MG63 osteoblasts

BACKGROUND

There is a growing awareness that oxidative stress may play a role in periodontal disease. The aim of this investigation was to evaluate potential oxidant/antioxidant interactions of nicotine with antioxidants (Coenzyme Q10 (CoQ), Pycnogenol and phytoestrogens in a cell culture model.

METHODS

Duplicate incubations of human periosteal fibroblasts and osteoblasts were performed with 14C-testosterone as substrate, in the presence or absence of CoQ (20 microg/ml), Pycnogenol (150 microg/ml), and phytoestrogens (10 and 40 microg/ml), alone and in combination with nicotine (250 microg/ml). At the end of a 24-h incubation period, the medium was solvent extracted and testosterone metabolites were separated by thin-layer chromatography and quantified using a radioisotope scanner.

RESULTS

The incubations of osteoblasts and periosteal fibroblasts with CoQ, Pycnogenol or phytoestrogens stimulated the synthesis of the physiologically active androgen DHT, while the yields of DHT were significantly reduced in response to nicotine compared to control values (p<0.001 for phytoestrogens). The combination of nicotine with CoQ, Pycnogenol or phytoestrogens increased the yields of DHT compared with incubation with nicotine alone in both cell types.

CONCLUSION

This investigation suggests that the catabolic effects of nicotine could be reversed by the addition of antioxidants such as CoQ or Pycnogenol and phytoestrogens.

Host response to microbial challenge following resective/non-resective periodontal therapy

BACKGROUND

The host response to microbial challenge depends on the recruitment of homing leucocytes and may be related to the experience to infectious insults over years.

PURPOSE

The aim of this study was to investigate the soft tissue reactions to de novo plaque formation at sites treated with either open flap debridement or with the use of resective means during periodontal therapy.

MATERIAL AND METHODS

Fifteen patients, who had been treated for periodontal disease (severe generalized chronic periodontitis), participated in the study. Surgical therapy was performed using either gingivectomy (GV) or open flap debridement (OFD) procedures in a split mouth design. After 6 months of healing (day 0), two gingival biopsies were obtained, one from the GV- and one from the OFD-treated sites. The experimental gingivitis model was applied and plaque accumulation was allowed for 3 weeks. New biopsies were obtained from the remaining quadrants on day 21 of plaque formation. The biopsies were snap frozen and prepared for immunohistochemical analysis.

RESULTS

Following 3 weeks of plaque accumulation, the size of the lesion in OFD sites was more than twice as large than that in GV sites (0.42 versus 0.19 mm2). In the GV units, the lesion was characterized by almost similar proportions of T cells (CD3+, 6.0%) and B cells (CD19+, 6.6%), while the ICT in OFD sites was dominated by B cells (13.8%). During the 3-week period of plaque formation the increase in cell densities of T and B cells was three times larger in OFD than in GV sites. The proportion of ELAM-1 (CD62+ cells) decreased in GV (-0.4%) and increased in OFD (0.9%) sites.

CONCLUSIONS

The host response that occurred in the gingival sites treated with OFD was more pronounced than the reaction that under similar experimental conditions took place in the regenerated gingiva at sites treated by resective means.