Levels of interleukin-1 beta and interleukin-8 in gingival crevicular fluids in adult periodontitis

Interleukin-38: A crucial player in periodontitis

BACKGROUND

The objective of this study was to compare the levels of gingival crevicular fluid (GCF), salivary, and serum matrix metalloproteinase-9, interleukin (IL)-17, IL-36γ, and IL-38 in individuals with healthy periodontium, gingivitis, and periodontitis and to evaluate their correlations with clinical periodontal parameters.

MATERIALS AND METHODS

Ninety systemically healthy and nonsmoking volunteers divided into a healthy (H) group (n = 30), a gingivitis (G) group (n = 30), and a periodontitis (P) group (n = 30) were included in this study. Clinical periodontal parameters of volunteers were recorded, and GCF, unstimulated saliva, and serum samples were collected. Data analysis was done with enzyme-linked immunosorbent assays. The Kruskal-Wallis test and Bonferroni correction were used for multiple comparisons and post hoc statistical analyses.

RESULTS

The group H had significantly lower clinical parameters than the group P (p < 0.001). GCF and salivary IL-36γ and IL-38 levels were significantly higher in the group P than in the H and G groups (p < 0.05). Positive correlations between biochemical findings and clinical periodontal parameters were observed.

CONCLUSIONS

IL-36γ and IL-38 levels in GCF, saliva, and serum correlate with clinical periodontal parameters and may play a role in determining the activity of periodontitis.

Microenvironmental regulation in tumor progression: Interactions between cancer-associated fibroblasts and immune cells

The tumor microenvironment (TME), the "soil" on which tumor cells grow, has an important role in regulating the proliferation and metastasis of tumor cells as well as their response to treatment. Cancer-associated fibroblasts (CAFs), as the most abundant stromal cells of the TME, can not only directly alter the immunosuppressive effect of the TME through their own metabolism, but also influence the aggregation and function of immune cells by secreting a large number of cytokines and chemokines, reducing the body's immune surveillance of tumor cells and making them more prone to immune escape. Our study provides a comprehensive review of fibroblast chemotaxis, malignant transformation, metabolic characteristics, and interactions with immune cells. In addition, the current small molecule drugs targeting CAFs have been summarized, including both natural small molecules and targeted drugs for current clinical therapeutic applications. A complete review of the role of fibroblasts in TME from an immune perspective is presented, which has important implications in improving the efficiency of immunotherapy by targeting fibroblasts.

Association between birth-related factors and periodontitis in women: Korea National Health and Nutrition Examination Survey 2013-2018

AIM

Adult women experience several changes in physiological status, such as pregnancy and childbirth, during their life cycle. This study analyses the association between birth-related factors (the number of childbirths, abortions and miscarriages) and periodontitis using data from the Korea National Health and Nutrition Examination Survey, which represents Korean adults.

MATERIALS AND METHODS

The study used data from Korea National Health and Nutrition Examination Survey VI and VII (2013-2018) and included 10,072 women 19 years or older, with no missing data on the variables assessed. Periodontitis was defined according to the Community Periodontal Index (CPI) criteria. Multiple logistic regression analysis, adjusting for age, household income, education, alcohol consumption, smoking, stress, body mass index, waist circumference, hypertension, diabetes mellitus, an oral examination within 1 year, daily tooth brushing frequency, hygiene products and self-perceived oral health as identified via logistic regression analyses, was performed to determine the association between birth-related variables and periodontitis.

RESULTS

In the crude model, the odds ratio (OR) showed a significantly increased risk of periodontitis (CPI ≥ 3) and severe periodontitis (CPI = 4) based on the number of childbirths, abortions and miscarriages (p < .05). After covariate adjustment, periodontitis (CPI ≥ 3) was associated with the number of childbirths (1: OR = 1.92; 95% confidence interval [CI]: 1.47-2.50; 2: OR = 2.03; 95% CI: 1.57-2.61; ≥3: OR = 2.11; 95% CI: 1.60-2.78). Furthermore, severe periodontitis (CPI = 4) was also associated with the number of childbirths (1: OR = 2.33; 95% CI: 1.24-4.38; 2: OR = 2.99; 95% CI: 1.62-5.52; ≥3: OR = 3.34; 95% CI: 1.79-6.21).

CONCLUSIONS

The findings of this large-scale, nationally representative study suggest that the number of childbirths is associated with the severity of periodontitis. However, the relationship between the number of abortions and miscarriages and periodontitis (CPI ≥ 3) or severe periodontitis (CPI = 4) is not significant.

Evaluation of IL-23p19/Ebi3 (IL-39) gingival crevicular fluid levels in periodontal health, gingivitis, and periodontitis

Objectives

IL-23p19/Ebi3 (IL-39) was described as a new IL-12 family member. The aim of this study is to evaluate the gingival crevicular fluid (GCF) IL-39 levels in periodontal diseases and health and to correlate them to GCF levels of IL-1β and periostin.

Materials and methods

Sixty-six adult patients were included in the study. The study design was comprised of three groups, each containing 22 individuals: the periodontally healthy (PH), gingivitis (G), and periodontitis (P) groups. The clinical periodontal parameters were recorded and GCF samples were collected from the participants. GCF interleukin (IL)-39, IL-1β, and periostin levels were examined using the enzyme-linked immunosorbent assay.

Results

GCF IL‑1β, periostin, and IL-39 levels were higher in the P and G groups than in the PH group (p < 0.001). Positive correlations were detected between all GCF biochemical parameters and clinical periodontal parameters (p < 0.05). In the multivariate generalized linear regression analysis, the P (β = 37.6, 95% CI = 22.9–52.4) and G (β = 28.4, 95% CI = 15.8–41) groups were associated with GCF IL-39 levels (p < 0.001).

Conclusion

IL-39 levels were elevated in the presence of periodontal disease paralleling the increase in IL‑1β and periostin levels. IL-39 may have a role in the periodontal inflammation process.

Statement of clinical relevance

IL-39, a new cytokine from the IL-12 family, can be a possible predictor marker of periodontal diseases.

Interleukin-34 Permits Porphyromonas gingivalis Survival and NF-κB p65 Inhibition in Macrophages

Interleukin-34 (IL-34) is a cytokine that supports the viability and differentiation of macrophages. An important cytokine for the development of epidermal immunity, IL-34 is present and plays a role in the immunity of the oral environment. IL-34 has been linked to inflammatory periodontal diseases, which involve innate phagocytes, including macrophages. Whether IL-34 can alter the ability of macrophages to effectively interact with oral microbes is currently unclear. Using macrophages derived from human blood monocytes with either the canonical cytokine colony-stimulating factor (CSF)1 or IL-34, we compared the ability of the macrophages to phagocytose, kill, and respond through the production of cytokines to the periodontal keystone pathogen Porphyromonas gingivalis. While macrophages derived from both cytokines were able to engulf the bacterium equally, IL-34 derived macrophages were much less capable of killing internalized P. gingivalis. Of the macrophage cell surface receptors known to interact with P. gingivalis, DC-SIGN was found to have the largest variation between IL-34 and CSF1-derived macrophages. We also found that upon interaction with P. gingivalis, IL-34 derived macrophages produced significantly less of the neutrophil chemotactic factor IL-8 than macrophages derived in the presence of CSF1. Mechanistically, we identified that levels of IL-8 corresponded with P. gingivalis survival and dephosphorylation of the major transcription factor NF-κB p65. Overall, we found that macrophages differentiated in the presence of IL-34, a dominant cytokine in the oral gingiva, have a reduced ability to kill the keystone pathogen P. gingivalis and may be susceptible to specific bacteria-mediated cytokine modification. This article is protected by copyright. All rights reserved.

Epstein-Barr Virus Promotes the Production of Inflammatory Cytokines in Gingival Fibroblasts and RANKL-Induced Osteoclast Differentiation in RAW264.7 Cells

Periodontitis is an inflammatory condition that causes the destruction of the supporting tissues of teeth and is a major public health problem affecting more than half of the adult population worldwide. Recently, members of the herpes virus family, such as the Epstein–Barr virus (EBV), have been suggested to be involved in the etiology of periodontitis because bacterial activity alone does not adequately explain the clinical characteristics of periodontitis. However, the role of EBV in the etiology of periodontitis is unknown. This study aimed to examine the effect of inactivated EBV on the expression of inflammatory cytokines in human gingival fibroblasts (HGFs) and the induction of osteoclast differentiation. We found that extremely high levels of interleukin (IL)-6 and IL-8 were induced by inactivated EBV in a copy-dependent manner in HGFs. The levels of IL-6 and IL-8 in HGFs were higher when the cells were treated with EBV than when treated with lipopolysaccharide and lipoteichoic acid. EBV induced IκBα degradation, NF-κB transcription, and RAW264.7 cell differentiation into osteoclast-like cells. These findings suggest that even without infecting the cells, EBV contributes to inflammatory cytokine production and osteoclast differentiation by contact with oral cells or macrophage lineage, resulting in periodontitis onset and progression.

Chemomechanical preparation influences the microbial community and the levels of LPS, LTA and cytokines in combined endodontic-periodontal lesions: A clinical study

BACKGROUND

This study was conducted to compare the microbiomes, the levels of lipopolysaccharides (LPS), lipoteichoic acid (LTA), and cytokines (interleukin [IL]-1β and tumor necrosis factor-alpha [TNF-α]), before and after chemomechanical preparation (CMP) of the root canals (RC) and their associated periodontal pockets (PP) in teeth with combined EPL.

MATERIALS

Samples were taken from 10 RC and PP, before and after CMP. The microbiomes (next-generation sequencing, V3-V4 hypervariable region of the 16S rRNA gene), microbiome diversity (bioinformatics analyses), LPS (limulus amebocyte lysate), LTA, IL-1β, and TNF-α (ELISA) were evaluated. A statistical analysis was performed with significance level set at 5%.

RESULTS

The most abundant phyla in both sites were Firmicutes and Proteobacteria. Comparative studies of bacterial genera species revealed that some increased and others decreased after CMP at both sites. A 3% reduction in Gram-negative bacteria (RC) and a 4% increase in Gram-positive bacteria (PP) were detected. LPS levels were 4.4 times higher in PP than in the RC. LTA was detected in all samples investigated. Higher levels of IL-1β and TNF-α were detected in both sites at baseline. After CMP, LPS, LTA, IL-1β and TNF-α were reduced in both sites.

CONCLUSION

The microbial community in the RC and PP in teeth with combined EPL indicated a similarity between both sites. CMP effectively reduced the microbial load and the LPS levels from teeth with EPL, and consequently diminished the cytokine levels. The reduction in LTA levels in the RC and PP proved challenging.

Therapeutic potential of a novel semi-synthetic-sulfated-polysaccharide to suppress inflammatory mediators in P. gingivalis LPS stimulated human monocytes/macrophages

BACKGROUND

Chronic periodontitis is associated with an increased risk for systemic conditions such as cardiovascular disease, diabetes, and osteoporosis. During chronic periodontitis, endotoxin (lipopolysaccharide, LPS) produced by P. gingivalis provokes monocyte accumulation and differentiation into macrophages and increased secretion of pro-inflammatory cytokines and matrix metalloproteases (MMPs). While normal levels of MMPs are important in cellular function, increased levels of cytokines and MMPs can cause connective tissue destruction.

RESULTS

In the current study, we investigated the therapeutic capability of a novel semi-synthetic sulfated polysaccharide (SAGE) on the production of cytokines and MMPs by cultured human mononuclear cells and macrophages stimulated with endotoxin LPS produced by P. gingivalis, a periodontally-relevant cell culture model. Our research demonstrated SAGE inhibited the LPS induced synthesis of inflammatory mediators including TNF-α, IL-1β, PGE₂, and MMP-9 in this periodontal-relevant cell culture model. In addition, TLR-2 and TLR-4 levels were also reduced with the SAGE treatment.

CONCLUSIONS

The therapeutic potential of this novel semi-synthetic sulfated polysaccharide compound may help to prevent tissue damage and bone loss in patients with periodontal disease or other inflammatory diseases.

Salivary and gingival CXCL8 correlation with periodontal status, periodontal pathogens and smoking

OBJECTIVES

Neutrophil granulocytes have been proposed to play a major role in the mediation of periodontitis-associated tissue destruction. Their recruitment and activation are regulated by the chemokine CXCL8. This study aimed to delineate the dependency of CXCL8-expression in gingival crevicular fluid (GCF) and saliva on periodontal status, bacterial infection and smoking, in patients with periodontitis.

METHODS

The study cohort comprised 279 subjects with untreated periodontitis. Probing pocket depth (PPD), gingival recession, bleeding on probing (BOP), plaque index, and bone loss were evaluated. CXCL8 was determined in saliva and GCF using flow cytometry.

RESULTS

Considering the entire study sample, CXCL8 levels were correlated with the mean PPD (ρ=0.131; p=0.029), severity of periodontitis (ρ=0.121; p=0.043), BOP (ρ=0.204; p=0.001) and smoking (ρ=-0.219; p<0.0001) in GCF; and, in whole saliva, with mean PPD (ρ=0.154; p=0.010) severity of periodontitis (ρ=0.140; p=0.020), gender (ρ=0.178; p=0.003) and smoking (ρ=-0.156; p=0.010). Subgroup analysis among non-smokers revealed significantly higher amounts of CXCL8 in GCF (p=0.012) and saliva (p=0.026) comparing subjects with mean PPD ≤3mm and >3mm.

CONCLUSION

The current study revealed a strong dependency of CXCL8-expression in GCF on the severity and activity of periodontal disease. Smoking causes a significant reduction of CXCL8-expression in saliva and GCF.

The effect of zirconia and titanium surfaces on biofilm formation and on host-derived immunological parameters

The aim of this study was to analyse the effect of zirconia and titanium surfaces on biofilm formation and host-derived parameters. Studies comparing zirconia and titanium surfaces were selected up to September 1, 2019. The outcome measures were surface roughness, contact angle, bacterial count, bacterial adherence, biofilm thickness, bacterial distribution, and specifically investigated biofilm and specific host-derived immunological parameters. Random-effects meta-analyses of in vitro and in vivo studies were conducted. A total of 39 studies were included for data extraction. In the systematic review data, 10 studies stated that zirconia accumulated less initial oral biofilm parameters, 16 investigations showed negligible inter-material differences, and only one study showed that zirconia attracted the most biofilm. However, in the meta-analysis, the bacterial coverage was found to be significantly superior for zirconia surfaces (P< 0.00001); the other outcome measures did not show any statistically significant differences between zirconia and titanium for the remaining parameters and the studies presented a substantial degree of heterogeneity. Overall, on the basis of the meta-analysis, the current data situation does not allow a clear preference for the use of zirconia or titanium.

Application of specialized pro-resolving mediators in periodontitis and peri-implantitis: a review

Scaling and root planning is a key element in the mechanical therapy used for the eradication of biofilm, which is the major etiological factor for periodontitis and peri‐implantitis. However, periodontitis is also a host mediated disease, therefore, removal of the biofilm without adjunctive therapy may not achieve the desired clinical outcome due to persistent activation of the innate and adaptive immune cells. Most recently, even the resident cells of the periodontium, including periodontal ligament fibroblasts, have been shown to produce several inflammatory factors in response to bacterial challenge. With increased understanding of the pathophysiology of periodontitis, more research is focusing on opposing excessive inflammation with specialized pro‐resolving mediators (SPMs). This review article covers the major limitations of current standards of care for periodontitis and peri‐implantitis, and it highlights recent advances and prospects of SPMs in the context of tissue reconstruction and regeneration. Here, we focus primarily on the role of SPMs in restoring tissue homeostasis after periodontal infection.

Immunomodulatory activity seen as a result of photobiomodulation therapy in stimulated primary human fibroblasts

OBJECTIVE

Oral biofilms burden host responses by induction of inflammatory mediators, exacerbating periodontal inflammation. Photobiomodulation Therapy (PBMT) has been shown to decrease levels of pro-inflammatory cytokines and chemokines. However, optimal wavelengths and exposure doses have not been established. This study investigated the effects of PBMT on human periodontal ligament fibroblasts (hPDLFs) stimulated with inflammatory mediators (LPS, TNF-α, and IL-1β).

METHODS

Cytotoxic effects of laser wavelengths 660 nm and 810 nm were assessed by measuring their effects on cellular dehydrogenase activity. The study was expanded to include 980 nm, 660 nm + 810 nm, and 810 nm + 980 nm. P.g. LPS, TNF-α, and/or IL-1β were added one hour before irradiation, then exposed to laser irradiation to determine the most appropriate stimulus. The levels of INF-γ, IL-6, IL-8, IL-17A/F, and MCP-1 production in stimulated hPDLFs were measured and analyzed.

RESULTS

P.g. LPS was a poor stimulus for hPDLFs, while TNF-α and IL-1β significantly elevated the analytes. The 660 nm laser treatment induced pro-inflammatory cytokines when stimulated, while 810 nm exhibited significant suppression. IL-1β was the stimulus of choice and the 810 nm wavelength alone exhibited anti-inflammatory effects for all analytes except IL-8, while the 810 nm in combination with 660 nm and/or 980 nm exhibited effects similar to 810 nm alone.

CONCLUSIONS

The downregulation of inflammatory mediators by the combination or individual treatment with 810 nm wavelength shows promise for the management of periodontal inflammation. PBMT may lead to the development of a novel approach in the management of periodontal disease.

Does peri-implant bone loss affect the LL-37 and proteinase 3 levels in peri-implant sulcus fluid?

BACKGROUND

Inactive human cathelicidin antimicrobial peptide is present in neutrophils, and proteinase 3 activates this peptide by producing active LL-37 peptide. LL-37 acts as a defensive peptide in the oral tissues. In the present study, the aim was to evaluate LL-37 and proteinase 3 levels in peri-implant sulcus fluid (PISF) in implants with and without peri-implantitis.

METHODS

Patients who simultaneously had dental implants with peri-implantitis and without peri-implantitis were included in the study. Forty-four samples with peri-implantitis and 34 samples without peri-implantitis from 16 patients were obtained. Intraoral evaluations such as pocket depth, modified sulcus bleeding index, and modified plaque index were noted. Enzyme-linked immunosorbent assay was used for the evaluation of PISF LL-37 and proteinase 3 levels.

RESULTS

PISF volume was significantly increased in the implants with peri-implantitis than those without peri-implantitis (p < 0.05). No difference was present between PISF LL-37 and proteinase 3 total amounts between the implants with and without peri-implantitis (p > 0.05). Pocket depths and PISF LL-37 and proteinase 3 levels were not correlated in the groups (p > 0.05).

CONCLUSIONS

PISF volume might be increased in response to peri-implant bone destruction. However, peri-implant tissue destruction caused by peri-implantitis does not seem to affect PISF LL-37 and proteinase 3 levels.

Cannabinoid type-2 receptor agonist, inverse agonist, and anandamide regulation of inflammatory responses in IL-1β stimulated primary human periodontal ligament fibroblasts

OBJECTIVE

The aim of this study is to understand the role of cannabinoid type 2 receptor (CB2R) during periodontal inflammation and to identify anti-inflammatory agents for the development of drugs to treat periodontitis (PD).

BACKGROUND

Cannabinoid type 2 receptor is found in periodontal tissue at sites of inflammation/infection. Our previous study demonstrated anti-inflammatory responses in human periodontal ligament fibroblasts (hPDLFs) via CB2R ligands.

METHODS

Anandamide (AEA), HU-308 (agonist), and SMM-189 (inverse agonist) were tested for effects on IL-1β-stimulated cytokines, chemokines, and angiogenic and vascular markers expressed by hPDLFs using Mesoscale Discovery V-Plex Kits. Signal transduction pathways (p-c-Jun, p-ERK, p-p-38, p-JNK, p-CREB, and p-NF-kB) were investigated using Cisbio HTRF kits. ACTOne and Tango™ -BLA functional assays were used to measure cyclic AMP (cAMP) and β-arrestin activity.

RESULTS

IL-1β stimulated hPDLF production of 18/39 analytes, which were downregulated by the CB2R agonist and the inverse agonist. AEA exhibited pro-inflammatory and anti-inflammatory effects. IL-1β increased phosphoproteins within the first hour except p-JNK. CB2R ligands attenuated p-p38 and p-NFĸB, but a late rise in p-38 was seen with HU-308. As p-ERK levels declined, a significant increase in p-ERK was observed later in the time course by synthetic CB2R ligands. P-JNK was significantly affected by SMM-189 only, while p-CREB was elevated significantly by CB2R ligands at 180 minutes. HU-308 affected both cAMP and β-arrestin pathway. SMM-189 only stimulated cAMP.

CONCLUSION

The findings that CB2R agonist and inverse agonist may potentially regulate inflammation suggest that development of CB2R therapeutics could improve on current treatments for PD and other oral inflammatory pathologies.

EBV LMP1 in Gingival Epithelium Potentially Contributes to Human Chronic Periodontitis via Inducible IL8 Production

BACKGROUND/AIM

Human chronic periodontitis is a major health problem. Although some oral bacteria have been reported to be putative pathogens, Epstein-Barr virus (EBV) is reported to be associated with the progression of periodontitis. However, the role of EBV in the aetiology of periodontitis is unknown. Therefore, we investigated periodontal pathogenesis of EBV to confirm whether EBV-encoded latent membrane protein 1 (LMP1) induces Interleukin-8 (IL8) production in human gingival cells.

MATERIALS AND METHODS

Real-time polymerase chain reaction, luciferase assay, enzyme-linked immunosorbent assay (ELISA), and western blotting were performed for determining IL8 mRNA expression, nuclear factor kappa B (NF-ĸB) transcription, IL8 production, and the phosphorylation of NF-ĸB p65 and Inhibitor of kappa B alpha (IĸBα), respectively, in Ca9-22 human gingival epithelial cells. Two LMP1 mutants lacking C-terminal activating region (CATR) domains responsible for activating NF-ĸB were used.

RESULTS

Extremely high IL8 production was induced by LMP1 in time- and dose-dependent manner, where simultaneous phosphorylation of NF-κB p65 and IĸBα and transcription of NF-ĸB were observed. On the contrary, IL8 production and NF-ĸB transcription were drastically inhibited by dominant negative mutant of IĸBα. Moreover, the LMP1 mutants failed to induce IL8 production.

CONCLUSION

Our findings suggest that due to CATR domains, LMP1 contributes to the progression of periodontitis via IL8 production attributable to NF-ĸB activation.

Gingival crevicular fluid levels of interleukin-18 and tumor necrosis factor-alpha in type 1 diabetic children with gingivitis

OBJECTIVE

This study aimed to evaluate the levels of interleukin-18 and tumor necrosis factor-alpha in gingival crevicular fluid of diabetic children with gingivitis.

METHODOLOGY

Eighty-eight children (44 with type 1 diabetes mellitus and 44 systemically healthy) were recruited for the study. The children were divided into four subgroups based on their periodontal and systemic condition: (1) systemically and periodontally healthy children (H), (2) systemically healthy children with gingivitis (G), (3) periodontally healthy children with T1DM (T1DM + H), and (4) children with T1DM and gingivitis (T1DM + G). The plaque index, gingival index, probing pocket depth, and GCF volume were recorded. The IL-18 and TNF-α levels in GCF were determined by ELISA.

RESULTS

The clinical periodontal parameters, GCF IL-18 level, and TNF-α level were similar between diabetic and systemically healthy children (p > 0.05). The gingivitis subgroups had a significantly higher GI, PI, PPD, GCF volume, and TNF-α total amounts than the H subgroups (p < 0.0001). The IL-18 concentrations in the gingivitis subgroups were significantly lower than in the periodontally healthy subgroups.

CONCLUSIONS

In diabetic children with good metabolic control, T1DM did not affect the GCF levels of IL-18 and TNF-α in the presence of gingivitis. However, increased GCF TNF-α levels in children with gingivitis confirm that TNF-α is closely related to gingival inflammation.

CLINICAL RELEVANCE

Type 1 diabetes mellitus is not associated with GCF interleukin-18 and tumor necrosis factor-alpha levels in children with gingivitis.

Influence of Smoking on Gingival Crevicular Fluid Interleukin 1β and Interleukin-8 in Patients with Severe Chronic Periodontitis among a Rural Population in India

Background and Objective:

Smoking is widely prevalent among rural Indian populations. Smoking is considered a significant risk factor for periodontal diseases. The aim of the present study was to evaluate the influence of smoking on the inflammatory cytokines interleukin (IL) IL-1β and IL-8 in gingival crevicular fluid (GCF) and compare these between smokers and nonsmokers with periodontitis in diseased and healthy sites.

Materials and Methods:

A total of thirty patients with severe chronic periodontitis (15 smokers and 15 nonsmokers) participated in this study. Clinical parameters assessed were gingival index, bleeding on probing, probing depth (PD), and clinical attachment level. One diseased and one healthy site from each of the periodontitis patients were selected for GCF collection and assigned to the following four groups: healthy sites in smoker (SH), diseased sites in smoker (SD), healthy sites in nonsmoker (NH), and diseased sites in nonsmoker (ND) and were analyzed by enzyme-linked immunosorbent assay test (Quantikine^®).

Results:

Intragroup comparisons revealed statistically significant levels of IL-1β in ND sites compared to NH sites (P < 0.005) and SD sites showed statistically significantly higher levels of IL-1β compared to SH sites (P < 0.0001). However, there was no significant difference in IL-8 levels between NH and ND sites as well as between SH and SD sites. Intergroup comparisons revealed that SH sites exhibited significantly lower amounts of IL-8 (P < 0.01) compared to NH sites and SD sites showed significantly lower levels of IL-8 compared to ND sites (P < 0.001). However, the comparison of NH and SH sites as well as ND and SD sites showed no significant difference in the levels of IL-1β.

Conclusions:

Cytokine levels were significantly elevated in periodontitis patients. Smokers exhibited a decrease in IL-8 and increase in IL-1β levels. Hence, this reflects the influence of smoking on immunosuppression and its role in the pathogenesis of periodontal disease.

Evaluation of milk fat globule-epidermal growth factor-factor VIII and IL-1β levels in gingival crevicular fluid and saliva in periodontal disease and health

The aim of this study is to determine the levels of MFG-E8 and interleukin (IL)-1β in saliva and gingival crevicular fluid (GCF) associated with periodontal health and disease. Whole saliva and GCF samples were obtained from systemically healthy participants who were either periodontally healthy (n = 24) or suffered from gingivitis (n = 25) or chronic periodontitis (n = 25). Full-mouth clinical periodontal measurements, including bleeding on probing, probing depth, gingival index, plaque index, and clinical attachment level were also recorded. Enzyme-linked immunosorbent assay was used to estimate MFG-E8 and IL-1β levels in the samples. Analysis of variance, Kruskal-Wallis tests, and Pearson correlation tests were used to analyse the data statistically. The total level of MFG-E8 in GCF was significantly higher in the healthy group than in the other two groups (P = 0.01). Salivary MFG-E8 levels did not differ significantly among the groups. There were negative correlations between the level of MFG-E8 in GCF and probing depth (P = 0.03), bleeding on probing (P = 0.001), plaque index (P = 0.003), and gingival index (P = 0.003). The total level of IL-1β in GCF was significantly lower in the healthy group than in the groups with gingivitis and chronic periodontitis (P < 0.001). Salivary IL-1β levels showed significant differences across all three groups (P < 0.001). The level of MFG-E8 in GCF was higher in the healthy group than in the periodontal disease groups. Furthermore, there was no difference between gingivitis and periodontitis groups. The relationship between MFG-E8 and periodontal status should be further investigated.

Effect of intracanal diode laser application and low-level laser therapy on CGRP change

The aim of this study was to investigate the effect of a placebo, intracanal diode laser application, and low-level laser therapy (LLLT) on the change of the total amount of calcitonin gene-related peptide (CGRP) in the gingival crevicular fluid (GCF) (split-mouth study design). GCF sampling was performed on a contralateral tooth and experimental tooth (root canal-treated tooth) of thirty-nine patients. The patients were divided into three groups (n = 13), as follows: placebo (mock laser application), intracanal laser application, and LLLT. GCF sampling was repeated at the same sites (experimental and control teeth) one week after root canal treatment. The data were analyzed using the Pearson's correlation analysis and the independent-samples t-tests (p=0.05). In the placebo group, the total CGRP level changes in the GCF before and after treatment was significantly higher for experimental teeth than for control teeth (p<0.05). However, there was no significant difference between experimental and control teeth in the intracanal laser application and LLLT groups (p > 0.05). Intracanal laser application and low-level laser therapy have immunomodulation effects linked to the modulation of the total amount of CGRP in the GCF.

Effects of non-surgical periodontal therapy on clinical and immunological profile and oral colonization of Candida spp in HIV-infected patients with chronic periodontitis

BACKGROUND

After the introduction of antiretroviral therapy (ART), human immunodeficiency virus (HIV) infection has become a chronic controllable disease. For this reason, chronic conditions related to both HIV infection and senescence, such as chronic periodontitis (CP) need to be studied. This study investigated the impact of non-surgical periodontal therapy (NSPT) on clinical and immunological features of CP, and on oral colonization by Candida spp. in HIV-infected and non-HIV-infected individuals.

METHODS

HIV-infected (test group) and non-HIV-infected (control group) adults patients with CP were selected. Gingival bleeding index (GI), probing depth (PD), clinical attachment level (CAL), number of teeth, CD4+ T lymphocytes and viral load (only for HIV-infected individuals), salivary cytokines (interleukin, [IL]-6, IL-8, and tumoral necrosis factor-alpha [TNF-α]), and oral Candida infection (colony forming units and species) were assessed at baseline, and 30 and 90 days after NSPT.

RESULTS

Twenty-two HIV-infected patients and 20 non-HIV-infected patients were evaluated. Candida counts and salivary IL-6, IL-8, and TNF-a levels were higher in the test group than in the control group. Both groups showed a decrease in oral Candida counts, GI, PD, IL-6, and IL-8 as well as gain in CAL at 30 and 90 days after NSPT. In addition, patients in the test group showed an increase of CD4+ T lymphocytes and a decrease of viral load.

CONCLUSION

NSPT had a beneficial impact on clinical and immunological parameters of CP, reduction of oral Candida counts, and improvement of HIV-infection status.

A Chemically Modified Curcumin (CMC 2.24) Inhibits Nuclear Factor κB Activation and Inflammatory Bone Loss in Murine Models of LPS-Induced Experimental Periodontitis and Diabetes-Associated Natural Periodontitis

The purpose of this study was to assess the effect of a novel chemically modified curcumin (CMC 2.24) on NF-κB and MAPK signaling and inflammatory cytokine production in two experimental models of periodontal disease in rats. Experimental model I: Periodontitis was induced by repeated injections of LPS into the gingiva (3×/week, 3 weeks); control rats received vehicle injections. CMC 2.24, or the vehicle, was administered by daily oral gavage for 4 weeks. Experimental model II: Diabetes was induced in adult male rats by streptozotocin injection; periodontal breakdown then results as a complication of uncontrolled hyperglycemia. Non-diabetic rats served as controls. CMC 2.24, or the vehicle, was administered by oral gavage daily for 3 weeks to the diabetics. Hemimaxillae and gingival tissues were harvested, and bone loss was assessed radiographically. Gingival tissues were pooled according to the experimental conditions and processed for the analysis of matrix metalloproteinases (MMPs) and bone-resorptive cytokines. Activation of p38 MAPK and NF-κB signaling pathways was assessed by western blot. Both LPS and diabetes induced an inflammatory process in the gingival tissues associated with excessive alveolar bone resorption and increased activation of p65 (NF-κB) and p38 MAPK. In both models, the administration of CMC 2.24 produced a marked reduction of inflammatory cytokines and MMPs in the gingival tissues, decreased bone loss, and decreased activation of p65 (NF-κB) and p38 MAPK. Inhibition of these cell signaling pathways by this novel tri-ketonic curcuminoid (natural curcumin is di-ketonic) may play a role in its therapeutic efficacy in locally and systemically associated periodontitis.

A pilot study of the gingival response when smokers switch from smoking to vaping

Introduction Tobacco smoking is one of the most important risk factors for periodontitis as it alters the host response to plaque. Although the prevalence of tobacco smoking has declined in recent years, the use of electronic-cigarettes (vaping) has increased. The effect of vaping on the gingiva is unknown and an evidence-base needs to be established before providing dental advice about the use of these products.Objective To compare the gingival health of a group of established smokers before and after substituting vaping for smoking tobacco.Design Pilot.Setting Guy's Dental Hospital (England) from April-December 2015.Materials and methods Twenty established smokers (all staff members at Guy's Hospital) with mild periodontal disease replaced their regular smoking habits with the use of e-cigarettes for two weeks.Main outcome measure The primary outcome measure of gingival inflammation was bleeding on probing. Levels of selected pro-inflammatory cytokines in GCF, saliva and serum samples were also determined.Results and conclusions There was a statistically significant increase in gingival inflammation when tobacco smokers switched from smoking to vaping for two weeks. However, this result must be interpreted with extreme caution since this is only a pilot study. Nonetheless, this study should provide a stepping stone to encourage further investigation of the effects of vaping on periodontal health.

Diamond burs versus curettes in root planing: a randomized clinical trial

BACKGROUND

This study compares diamond burs and curettes by clinical, microbiological, biochemical and scanning electron microscopic parameters and treatment time data in the non-surgical periodontal treatment of patients with chronic periodontitis.

METHODS

Two quadrants of each of the 12 patients received root planing with diamond burs, whereas the other two quadrants were treated with curettes. Clinical periodontal measurements were recorded at baseline and then 1, 3 and 6 months after completion of non-surgical periodontal treatment. Subgingival plaque and gingival crevicular fluid samples were obtained at baseline and 1-month control. Twenty-one hopeless teeth received root planing with diamond burs or curettes or no treatment and then extracted for microscopic evaluations.

RESULTS

Clinical periodontal parameters improved similarly with both treatment modalities. Microbiological analyses revealed similar findings for the bacterial load (16S gene copy numbers) and ratio of each bacterium to the total bacterial count at baseline and 1-month control. Cytokine levels in the gingival crevicular fluid samples exhibited differences between the two treatments. Scanning electron microscopic analyses indicated that diamond burs were better in terms of calculus removal and loss of tooth substance indices but roughness index values were better for curettes.

CONCLUSIONS

Diamond burs provide findings comparable with curettes in root planing.

Damage-regulated autophagy modulator 1 in oral inflammation and infection

OBJECTIVES

Damage-regulated autophagy modulator (DRAM) 1 is a p53 target gene with possible involvement in oral inflammation and infection. This study sought to examine the presence and regulation of DRAM1 in periodontal diseases.

MATERIAL AND METHODS

In vitro, human periodontal ligament fibroblasts were exposed to interleukin (IL)-1β and Fusobacterium nucleatum for up to 2 days. The DRAM1 synthesis and its regulation were analyzed by real-time PCR, immunocytochemistry, and ELISA. Expressions of other autophagy-associated genes were also studied by real-time PCR. In vivo, synthesis of DRAM1 in gingival biopsies from rats and patients with and without periodontal disease was examined by real-time PCR and immunohistochemistry. For statistics, ANOVA and post-hoc tests were applied (p < 0.05).

RESULTS

In vitro, DRAM1 was significantly upregulated by IL-1β and F. nucleatum over 2 days and a wide range of concentrations. Additionally, increased DRAM1 protein levels in response to both stimulants were observed. Autophagy-associated genes ATG3, BAK1, HDAC6, and IRGM were also upregulated under inflammatory or infectious conditions. In vivo, the DRAM1 gene expression was significantly enhanced in rat gingival biopsies with induced periodontitis as compared to control. Significantly increased DRAM1 levels were also detected in human gingival biopsies from sites of periodontitis as compared to healthy sites.

CONCLUSION

Our data provide novel evidence that DRAM1 is increased under inflammatory and infectious conditions in periodontal cells and tissues, suggesting a pivotal role of DRAM1 in oral inflammation and infection.

CLINICAL RELEVANCE

DRAM1 might be a promising target in future diagnostic and treatment strategies for periodontitis.

Regulation of defensive function on gingival epithelial cells can prevent periodontal disease

Periodontal disease is a bacterial biofilm-associated inflammatory disease that has been implicated in many systemic diseases. A new preventive method for periodontal disease needs to be developed in order to promote the health of the elderly in a super-aged society. The gingival epithelium plays an important role as a mechanical barrier against bacterial invasion and a part of the innate immune response to infectious inflammation in periodontal tissue. The disorganization of cell–cell interactions and subsequent inflammation contribute to the initiation of periodontal disease. These make us consider that regulation of host defensive functions, epithelial barrier and neutrophil activity, may become novel preventive methods for periodontal inflammation. Based on this concept, we have found that several agents regulate the barrier function of gingival epithelial cells and suppress the accumulation of neutrophils in the gingival epithelium. We herein introduce the actions of irsogladine maleate, azithromycin, amphotericin B, and Houttuynia cordata (dokudami in Japanese), which is commonly used in traditional medicine, on the epithelial barrier and neutrophil migration in gingival epithelial cells in vivo and in vitro, in order to provide support for the clinical application of these agents to the prevention of periodontal inflammation.

Outer Membrane Vesicles Prime and Activate Macrophage Inflammasomes and Cytokine Secretion In Vitro and In Vivo

Outer membrane vesicles (OMVs) are proteoliposomes blebbed from the surface of Gram-negative bacteria. Chronic periodontitis is associated with an increase in subgingival plaque of Gram-negative bacteria, Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia. In this study, we investigated the immune-modulatory effects of P. gingivalis, T. denticola, and T. forsythia OMVs on monocytes and differentiated macrophages. All of the bacterial OMVs were phagocytosed by monocytes, M(naïve) and M(IFNγ) macrophages in a dose-dependent manner. They also induced NF-κB activation and increased TNFα, IL-8, and IL-1β cytokine secretion. P. gingivalis OMVs were also found to induce anti-inflammatory IL-10 secretion. Although unprimed monocytes and macrophages were resistant to OMV-induced cell death, lipopolysaccharide or OMV priming resulted in a significantly reduced cell viability. P. gingivalis, T. denticola, and T. forsythia OMVs all activated inflammasome complexes, as monitored by IL-1β secretion and ASC speck formation. ASC was critical for OMV-induced inflammasome formation, while AIM2-/- and Caspase-1-/- cells had significantly reduced inflammasome formation and NLRP3-/- cells exhibited a slight reduction. OMVs were also found to provide both priming and activation of the inflammasome complex. High-resolution microscopy and flow cytometry showed that P. gingivalis OMVs primed and activated macrophage inflammasomes in vivo with 80% of macrophages exhibiting inflammasome complex formation. In conclusion, periodontal pathogen OMVs were found to have significant immunomodulatory effects upon monocytes and macrophages and should therefore influence pro-inflammatory host responses associated with disease.

Association between interleukin-8 levels and chronic periodontal disease: A PRISMA-compliant systematic review and meta-analysis

BACKGROUND

Current publications present contradictory findings regarding interleukin-8 (IL-8) levels in patients with chronic periodontitis (CP). This systematic review compile evidences of the IL8 mRNA and protein levels in gingival tissue, saliva, and gingival crevicular fluid (GCF) investigated in patients with CP. Moreover, 2 meta-analyses were made focusing on the IL-8 levels in GCF and saliva of patients with or without CP.

METHODS

Electronic searches of the PubMed, Web of Science, and Scopus databases were conducted for publications up to February 2016 that investigated the levels of IL-8 detected in individuals with CP compared with health individuals. A total of 31 publications were included in the systematic review. For meta-analyses, the strength of association was calculated by pooled odds ratios with 95% confidence intervals using RevMan 5.1 software. Heterogeneity was examined using Higgins I-squared, tau-squared, and χ tests.

RESULTS

In biopsies of gingival tissue of CP patients, all studies found higher IL8 mRNA levels, and the majority of studies showed higher IL-8 protein levels in this tissue of individuals with moderate to severe CP. Four studies investigating the IL-8 levels in saliva showed inconclusive results. In spite of some studies seemed to indicate higher levels of IL-8 in GCF of CP patients, the meta-analysis results showed significantly lower IL-8 levels (pg/μL) in GCF of CP patients in comparison with periodontally healthy subjects.

CONCLUSIONS

We concluded that IL8 gene expression and IL-8 protein levels were higher in gingival tissues of CP patients when compared to periodontally health individuals. Meta-analysis of studies that measured IL-8 (pg/uL) in GCF found lower levels in CP patients. There are conflicting evidences regarding IL-8 levels in saliva.

Epithelial barrier and oral bacterial infection

The oral epithelial barrier separates the host from the environment and provides the first line of defense against pathogens, exogenous substances and mechanical stress. It consists of underlying connective tissue and a stratified keratinized epithelium with a basement membrane, whose cells undergo terminal differentiation resulting in the formation of a mechanically resistant surface. Gingival keratinocytes are connected by various transmembrane proteins, such as tight junctions, adherens junctions and gap junctions, each of which has a specialized structure and specific functions. Periodontal pathogens are able to induce inflammatory responses that lead to attachment loss and periodontal destruction. A number of studies have demonstrated that the characteristics of pathogenic oral bacteria influence the expression and structural integrity of different cell-cell junctions. Tissue destruction can be mediated by host cells following stimulation with cytokines and bacterial products. Keratinocytes, the main cell type in gingival epithelial tissues, express a variety of proinflammatory cytokines and chemokines, including interleukin-1alpha, interleukin-1beta, interleukin-6, interleukin-8 and tumor necrosis factor-alpha. Furthermore, the inflammatory mediators that may be secreted by oral keratinocytes are vascular endothelial growth factor, prostaglandin E2 , interleukin-1 receptor antagonist and chemokine (C-C motif) ligand 2. The protein family of matrix metalloproteinases is able to degrade all types of extracellular matrix protein, and can process a number of bioactive molecules. Matrix metalloproteinase activities under inflammatory conditions are mostly deregulated and often increased, and those mainly relevant in periodontal disease are matrix metalloproteinases 1, 2, 3, 8, 9, 13 and 24. Viral infection may also influence the epithelial barrier. Studies show that the expression of HIV proteins in the mucosal epithelium is correlated with the disruption of epithelial tight junctions, suggesting a possible enhancement of human papilloma virus infection by HIV-associated disruption of tight junctions. Altered expression of matrix metalloproteinases was demonstrated in keratinocytes transformed with human papilloma virus-16 or papilloma virus-18,. To summarize, the oral epithelium is able to react to a variety of exogenous, possibly noxious influences.

Visfatin levels in gingival crevicular fluid and serum before and after non-surgical treatment for periodontal diseases

The purpose of this study was to evaluate visfatin levels at different stages of periodontal disease and in healthy tissues. In addition, the effect of non-surgical periodontal therapy on visfatin levels in gingival crevicular fluid and serum was investigated. Forty-five patients were divided into three groups based on clinical and radiographical findings. Group 1 comprised periodontally healthy individuals (n = 15); group 2 comprised patients with gingivitis (n = 15); and group 3 was composed of patients with generalized chronic periodontitis (n = 15). Gingival crevicular fluid and serum samples were collected before treatment and at 1, 3, and 6 months after treatment. Visfatin levels were measured by enzyme-linked immunosorbent assays. Gingival crevicular fluid and serum visfatin levels were higher in patients with chronic periodontitis than those with gingivitis or healthy controls (P < 0.016). In addition, visfatin levels were higher in the gingivitis group than in healthy controls (P < 0.016). Non-surgical periodontal treatment resulted in a significant reduction in gingival crevicular fluid and serum visfatin levels. Furthermore, visfatin levels increased with inflammation and decreased following periodontal treatment. Our findings suggest that visfatin is an inflammatory biomarker of periodontal disease.(J Oral Sci 58, 491-499, 2016).

Chemokines in Oral Inflammatory Diseases: Apical Periodontitis and Periodontal Disease

The inflammatory oral diseases are characterized by the persistent migration of polymorphonuclear leukocytes, monocytes, lymphocytes, plasma and mast cells, and osteoblasts and osteoclasts. In the last decade, there has been a great interest in the mediators responsible for the selective recruitment and activation of these cell types at inflammatory sites. Of these mediators, the chemokines have received particular attention in recent years. Chemokine messages are decoded by specific receptors that initiate signal transduction events, leading to a multitude of cellular responses, including chemotaxis and activation of inflammatory and bone cells. However, little is known about their role in the pathogenesis of inflammatory oral diseases. The purpose of this review is to summarize the findings regarding the role of chemokines in periapical and periodontal tissue inflammation, and the integration, into experimental models, of the information about the role of chemokines in human diseases.

The paradox of painless periodontal disease

Periodontal diseases, primarily gingivitis and periodontitis, are characterised by progressive inflammation and tissue destruction. However, they are unusual in that they are not also accompanied by the pain commonly seen in other inflammatory conditions. This suggests that interactions between periodontal bacteria and host cells create a unique environment in which the pro-algesic effects of inflammatory mediators and factors released during tissue damage are directly or indirectly inhibited. In this review, we summarise the evidence that periodontal disease is characterised by an accumulation of classically pro-algesic factors from bacteria and host cells. We then discuss several mechanisms by which inflammatory sensitisation of nociceptive fibres could be prevented through inactivation or inhibition of these factors. Further studies are necessary to fully understand the molecular processes underlying the endogenous localised hypoalgesia in human periodontal disease. This knowledge might provide a rational basis to develop future therapeutic interventions, such as host modulation therapies, against a wide variety of other human pain conditions.

Gingival crevicular fluid levels of cytokines/chemokines in chronic periodontitis: a meta-analysis

AIMS

To compare gingival crevicular fluid (GCF) cytokines/chemokines levels between periodontally healthy subjects and subjects diagnosed with chronic periodontitis (ChP), before and after non-surgical periodontal treatment, and to establish their predictive value for periodontal disease progression.

METHODS

Studies indexed in MEDLINE and EMBASE published in English, Portuguese and Spanish were eligible for this review. Database searches up to December 2015, and manual search of the reference list from reviews and selected articles was performed. Only studies providing data on GCF cytokines/chemokines levels in subjects diagnosed with ChP and periodontally healthy controls were included. Cross-sectional, case series, single-arm clinical studies, randomized controlled trials and prospective/retrospective cohort studies were included. Meta-analyses were conducted for those cytokines/chemokines with at least three available studies.

RESULTS

GCF levels of IL-1β, IL-6, IFN-γ and MCP-1/CCL2 were significantly higher in subjects diagnosed with ChP than periodontally healthy subjects. A significant decrease in GCF levels of IL-1β and IL-17 was observed after non-surgical periodontal treatment, whereas a significant increase was observed for IL-4.

CONCLUSION

Evidence for significant differences between periodontal health and ChP was observed for a few cytokines and one chemokine. No conclusions could be drawn with regards to increased risk of disease progression.

Evaluation of gingival crevicular fluid cyclophilin a and extracellular matrix metalloproteinase inducer levels in different periodontal diseases

OBJECTIVE

Cyclophilin A (CypA) is able to regulate inflammatory responses and matrix metalloproteinase production via its interaction with extracellular matrix metalloproteinase inducer (EMMPRIN). EMMPRIN is the cell surface receptor of CypA. The aim of the present study was to evaluate the gingival crevicular fluid (GCF) CypA and EMMPRIN levels in patients with chronic periodontitis (CP), generalized aggressive periodontitis (G-AgP) and periodontally healthy controls.

METHODS

Twenty CP patients, 19 G-AgP patients and 20 healthy control subjects were included in the present study. All study participants were non-smokers. Full mouth clinical periodontal parameters including probing depth, clinical attachment level, plaque index, and papilla bleeding index were recorded. GCF CypA and EMMPRIN levels were analyzed by enzyme-linked immunosorbent assay. Data were analyzed statistically with parametric and non-parametric tests.

RESULTS

GCF CypA total amount was higher in the G-AgP group compared to healthy controls (p<0.05), whereas CypA total amounts were similar in CP and healthy controls (p>0.05). No significant difference in GCF CypA total amount between CP and G-AgP was observed (p>0.05). Also, there was no significant difference in GCF EMMPRIN total amounts among the study groups (p>0.05).

CONCLUSION

Higher levels of GCF CypA in patients with G-AgP might demonstrate that CypA is associated with the inflammatory infiltrate and alveolar bone destruction of G-AgP. However, GCF CypA level does not seem to be affected by CP. Similar GCF EMMPRIN levels in diseased and healthy groups might suggest that EMMPRIN has role in the turn over of connective tissues in physiological conditions as well as pathological state.

Differential Responses of Pattern Recognition Receptors to Outer Membrane Vesicles of Three Periodontal Pathogens

Highly purified outer membrane vesicles (OMVs) of the periodontal pathogens, Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia were produced using tangential flow ultrafiltration, ultracentrifugation and Optiprep density gradient separation. Cryo-TEM and light scattering showed OMVs to be single lipid-bilayers with modal diameters of 75 to 158 nm. Enumeration of OMVs by nanoparticle flow-cytometry at the same stage of late exponential culture indicated that P. gingivalis was the most prolific OMV producer. P. gingivalis OMVs induced strong TLR2 and TLR4-specific responses and moderate responses in TLR7, TLR8, TLR9, NOD1 and NOD2 expressing-HEK-Blue cells. Responses to T. forsythia OMVs were less than those of P. gingivalis and T. denticola OMVs induced only weak responses. Compositional analyses of OMVs from the three pathogens demonstrated differences in protein, fatty acids, lipopolysaccharide, peptidoglycan fragments and nucleic acids. Periodontal pathogen OMVs induced differential pattern recognition receptor responses that have implications for their role in chronic periodontitis.

Effect of topical simvastatin (1.2 mg) on gingival crevicular fluid interleukin-6, interleukin-8 and interleukin-10 levels in chronic periodontitis - A clinicobiochemical study

OBJECTIVES

The impact of simvastatin (SMV), a cholesterol lowering drug, on bone metabolism appears to involve complex interaction with cholesterol metabolites, hormones, inflammatory mediators and growth factors, thus having direct influence on extent and severity of periodontitis. The present study aims to evaluate the in vivo effect of subgingivally delivered SMV gel (1.2 mg) as a local drug-delivery agent on clinical parameters and on interleukin-6 (IL-6), interleukin-8 (IL-8) and interleukin-10 (IL-10) levels in gingival crevicular fluid (GCF) of chronic periodontitis patients.

MATERIALS AND METHODS

50 patients were selected and categorized into two treatment groups: control (scaling and root planing) and test group (scaling and root planing with SMV gel). At initial appointment, clinical parameters were measured. Biochemical analysis of GCF samples was done to evaluate the amount of IL-6, IL-8 and IL-10. GCF sampling and clinical parameters were repeated at one and three months for both the groups.

RESULTS

SMV has an inhibitory effect on pro-inflammatory cytokines (IL-6, IL-8) and stimulatory effect on anti-inflammatory cytokines (IL-10) in GCF of periodontitis patients and has significantly positive effect on all clinical parameters except relative attachment level (RAL). The addition of SMV, thereby, further alters the levels of cytokine that reflect enhanced antibacterial host defence activity at that site.

CONCLUSION

Topical SMV has a beneficial effect on periodontal health. Removal of the bacterial plaque and subgingival delivery of SMV significantly modulates the chemokines present in GCF. To summarize, SMV shows promising role in the management of periodontitis.

Effect of the use of snuff on the levels of interleukin-1 β and interleukin-8 in the gingival crevicular fluid of periodontitis patients

Background:

Use of smokeless tobacco in the form of moist snuff placed in the oral cavity is popular in rural India. The aim of the present cross-sectional study was to determine the effect of snuff on periodontitis by assessing interleukin (IL)-1 β and IL-8 levels in gingival crevicular fluid.

Materials and Methods:

A total of 60 subjects were selected for this study. 40 subjects presented with periodontitis, which included 20 snuff users (SP) and 20 nonsnuff users (NS). 20 periodontally healthy patients formed the controls (healthy control: HC). The clinical parameters recorded were gingival index (GI), plaque index, calculus index, bleeding on probing (BOP), probing depth (PD), recession (RC), and clinical attachment level (CAL). The IL-1 β and IL-8 levels were assessed through enzyme-linked immunosorbent assay (Quantikine^®). Analysis of variance (ANOVA), post-hoc Tukey's, Kruskal-Walli's ANOVA and Mann-Whitney test was used for comparison among groups and P > 0.05 was considered statistically significant.

Results:

No significant difference was seen in levels of IL-1 β and IL-8 between SP and NS groups (P = 0.16, 0.97). However, both the periodontitis groups (SP and NS) had increased IL-β levels when compared to HC group (P = 0.01, 0.001). The snuff users showed significant increase in GI, BOP, RC, and CAL when compared with NS (P = 0.002, 0.001, 0.012, 0.002) whereas NS group had significant increase in PD (P = 0.003).

Conclusion:

Within the limitations of this study, use of snuff does not affect the host inflammatory response associated with periodontitis and leads to RC and increased CAL due to local irritant effect.

Azithromycin recovers reductions in barrier function in human gingival epithelial cells stimulated with tumor necrosis factor-α

OBJECTIVE

The gingival epithelium plays an important role in protecting against the invasion of periodontal pathogens, and the permeability of gingival epithelial cells has been implicated in the initiation of periodontitis. Azithromycin (AZM) has been used in the treatment of chronic inflammatory airway diseases because it regulates cell-cell contact in airway epithelial cells. Therefore, AZM may also regulate barrier function in gingival epithelial cells. In the present study, we examined the effects of AZM on the permeability of human gingival epithelial cells (HGEC) under inflammatory conditions in vitro.

MATERIALS AND METHODS

HGEC were stimulated by tumor necrosis factor-α (TNF-α) in the presence of AZM or p38 MAP kinase and ERK inhibitors. Permeability was assessed based on transepithelial electrical resistance (TER). The expression of E-cadherin, phosphorylated p38 MAP kinase, and ERK was analyzed by Western blotting.

RESULTS

TNF-α decreased TER in HGEC, and AZM and the p38 MAP kinase and ERK inhibitors recovered this decrease. AZM inhibited the phosphorylation of ERK and p38 MAP kinase in TNF-α-stimulated HGEC. Furthermore, AZM recovered the decrease in E-cadherin expression in HGEC stimulated with TNF-α.

CONCLUSIONS

These results suggested that AZM regulated gingival epithelial permeability through p38 MAP kinase and ERK signaling, and may contribute to suppress the inflammation in gingival tissue.

Level of Interleukin-35 in Gingival Crevicular Fluid, Saliva, and Plasma in Periodontal Disease and Health

BACKGROUND

A novel member of the interleukin (IL)-12 family, IL-35 is an important inhibitory cytokine released by regulatory T cells. The aim of this study is to evaluate gingival crevicular fluid (GCF), saliva, and plasma levels of IL-35 in periodontal disease and health.

METHODS

Samples of GCF, whole saliva, and plasma were obtained from systemically healthy, non-smoking individuals with gingivitis (n = 20) or chronic periodontitis (CP) (n = 20) and periodontally healthy individuals (n = 20). Full-mouth clinical periodontal measurements, including probing depth (PD), bleeding on probing, gingival index, and plaque index (PI), were also recorded. Enzyme-linked immunosorbent assay was used to determine IL-35 levels in the samples. Data were tested statistically by analysis of variance and Pearson rank correlation test.

RESULTS

All clinical parameters were significantly higher in the CP group than the healthy and gingivitis groups (P <0.001). The GCF total amount of IL-35 was significantly higher in the CP group than the other groups (P = 0.04), whereas the GCF concentration of IL-35 was significantly higher in the healthy group than the other groups (P = 0.002). There were significant differences among the study groups in terms of salivary IL-35 level (P <0.001), with the highest level observed in the healthy group and the lowest in the CP group. There was no statistical difference between groups in plasma levels of IL-35 (P >0.05). There was a positive correlation between GCF total amount of IL-35 and PD (r = 0.338, P = 0.03) and PI (r = 0.374, P = 0.005) parameters.

CONCLUSIONS

IL-35 could have an important role in suppressing periodontal inflammation and maintaining periodontal health. Additional studies are required to evaluate its role in periodontal diseases.

Periodontal innate immune mechanisms relevant to atherosclerosis

Atherosclerosis is a common cardiovascular disease in the USA where it is a leading cause of illness and death. Atherosclerosis is the most common cause for heart attack and stroke. Most commonly, people develop atherosclerosis as a result of diabetes, genetic risk factors, high blood pressure, a high-fat diet, obesity, high blood cholesterol levels, and smoking. However, a sizable number of patients suffering from atherosclerosis do not harbor the classical risk factors. Ongoing infections have been suggested to play a role in this process. Periodontal disease is perhaps the most common chronic infection in adults with a wide range of clinical variability and severity. Research in the past decade has shed substantial light on both the initiating infectious agents and host immunological responses in periodontal disease. Up to 46% of the general population harbors the microorganism(s) associated with periodontal disease, although many are able to limit the progression of periodontal disease or even clear the organism(s) if infected. In the last decade, several epidemiological studies have found an association between periodontal infection and atherosclerosis. This review focuses on exploring the molecular consequences of infection by pathogens that exacerbate atherosclerosis, with the focus on infections by the periodontal bacterium Porphyromonas gingivalis as a running example.