Focal adhesion kinase activation is required for TNF‐α‐induced production of matrix metalloproteinase‐2 and proinflammatory cytokines in cultured human periodontal ligament fibroblasts

Since focal adhesion kinase (FAK) was proposed as a mediator of the inflammatory response, we have investigated the role of this molecule in the release of inflammatory cytokines by cultured human periodontal ligament fibroblasts (HPDLFs), cells that are thought to be important in the patient's response to periodontal infection. Human periodontal ligament fibroblasts were stimulated by tumor necrosis factor alpha (TNF‐α) and its effects on interleukin (IL)‐6 and IL‐8 release were measured by ELISA. Expression of matrix metalloproteinase 2 (MMP‐2) protein was analysed by western blotting. The levels of IL6, IL8, and MMP2 mRNA were evaluated by real‐time PCR. Tumor necrosis factor alpha dose‐dependently induced the phosphorylation of FAK, whereas small interfering FAK (siFAK) inhibited TNF‐α‐induced FAK phosphorylation. Tumor necrosis factor alpha also stimulated the production of IL‐6, IL‐8, and MMP‐2 in a dose‐dependent manner. Knockdown of FAK significantly suppressed TNF‐α‐induced expression of IL6 and IL8 mRNA and release of IL‐6 and IL‐8 protein in HPDLFs. Similarly, MMP‐2 down‐regulation was significantly prevented by siFAK. Our results strongly suggest that knockdown of FAK can decrease the production of TNF‐α‐induced IL‐6, IL‐8, and MMP‐2 in HPDLFs. These effects may help in understanding the mechanisms that control expression of inflammatory cytokines in the pathogenesis of periodontitis.     

NOD mouse model for Sjögren's syndrome: lack of longitudinal stability

Objectives: The non‐obese diabetic (NOD) mouse is not only a widely used model for diabetes mellitus type I, but also for the chronic autoimmune disease Sjögren's syndrome (SS), mainly affecting salivary and lacrimal glands. We studied the efficacy of local recombinant serotype 2 adeno‐associated viral (rAAV2) vector transfer of immunomodulatory transgenes to alter the SS‐like disease in NOD mice. Data collected over a 2‐year period indicated a changing SS phenotype in these mice and this phenomenon was investigated. Methods: 10¹⁰ particles rAAV2LacZ/gland were delivered to both submandibular glands (SMGs) of NOD/LtJ mice at 8 weeks (before sialadenitis onset) of age. Salivary flow rates were determined at 8 weeks and time of killing. Blood glucose levels and body weights were measured weekly. After killing, saliva and SMGs were harvested. Analyses of salivary output, inflammatory infiltrates (focus score), SMG cytokine profile, body weight, and diabetes mellitus status were performed. Data from six different experimental studies over 2 years were analyzed and compared. Results: Salivary flow rate, focus score, and SMG cytokines interleukin (IL)‐2, IL‐4, IL‐6, IL‐10, IL‐12(p70), tumor necrosis factor‐α and IFNγ showed changes over time. There were no differences for body weight, diabetes mellitus prevalence, or blood glucose level of non‐diabetic mice. Conclusion: This retrospective report is the first to describe longitudinal variability in the NOD mouse as a model for SS. We advise other investigators to continuously monitor the SS phenotype parameters and include appropriate controls when studying this disease in NOD mice.     

Correlation between periodontal disease, inflammatory alterations and pre-eclampsia

Politano GT, Passini R, Nomura ML, Velloso L, Morari J, Couto E. Correlation between periodontal disease, inflammatory alterations and pre‐eclampsia. J Periodont Res 2011; 46: 505–511. © 2011 John Wiley & Sons A/S Background and Objective: Several studies have hypothesized that periodontal disease may increase the risk of pre‐eclampsia. The correlation between the two diseases would probably be based on hypertension‐related cytokine release in the local periodontal environment. The aim of this study was to evaluate the association between periodontal disease and pre‐eclampsia, and the correlation of the two conditions with interleukin‐6 (IL‐6) and tumor necrosis factor‐α(TNFα) mRNA expression. Material and Methods: A case–control analysis of 116 pregnant women, 58 with pre‐eclampsia (cases) and 58 normotensive pregnant women (controls) was performed. In addition to collection of socio‐demographic data and periodontal evaluation, peripheral blood samples were collected for laboratory analysis of IL‐6 and TNFα mRNA expression by real‐time PCR. Results: There was an association between periodontitis and pre‐eclampsia (adjusted odds ratio 3.73; 95% confidence interval 1.32–10.58). Increased TNFα mRNA expression was observed in pre‐eclamptic women; however, there was no correlation between periodontitis and systemic cytokine expression. In the case group, systemic cytokine mRNA levels were similar in pregnant women with and without periodontitis (means ± SD): 0.73 ± 0.24 vs. 0.82 ± 0.38 for TNFα and 1.31 ± 1.49 vs. 1.09 ± 0.74 for IL‐6, respectively. Conclusion: Periodontitis was clinically related to pre‐eclampsia; however, the supposed mechanism that correlates the two diseases, i.e. a systemic inflammatory process involving cytokines TNFα and IL‐6 in the presence of periodontal disease, could not be confirmed in this study.     

Histamine deficiency inhibits lymphocyte infiltration in the submandibular gland of aged mice via increased anti-aging factor Klotho

ObjectivesHistidine decarboxylase (HDC), a histamine synthase, is expressed in various tissues and is induced by proinflammatory cytokines such as TNFα. As they age, C57BL/6 mice show auto-antibody deposition and lymphocyte infiltration into various tissues, including salivary glands. However, the mechanism underlying cell infiltration and the change in HDC expression in salivary glands with aging remain unclear. Thus, we aimed to elucidate the relationship between histamine and inflammaging.MethodsWe investigated the change in histology and HDC expression in the major salivary glands (parotid, submandibular, and sublingual) of 6-week- and 9-month-old wild-type mice. We also determined the histological changes, cytokine expression, and anti-aging factor Klotho in the salivary glands of 9-month-old wild-type and HDC-deficient (HDC-KO) mice.ResultsCell infiltration was observed in the submandibular gland of 9-month-old wild-type mice. Although most cells infiltrating the submandibular glands were CD3-positive and B220-positive lymphocytes, CD11c-positive and F4/80-positive monocyte lineages were also detected. HDC, TNFα, and IL-1β mRNA expression increased in the submandibular gland of 9-month-old wild-type mice. The expression of PPARγ, an anti-inflammatory protein, declined in 9-month-old wild-type mice, and Klotho expression increased in 9-month-old HDC-KO mice. Immunohistochemistry showed that Klotho-positive cells disappeared in the submandibular gland of 9-month-old wild-type mice, while Klotho was detected in all salivary glands in HDC-KO mice of the same age.ConclusionOur findings demonstrate the multifunctionality of histamine and can aid in the development of novel therapeutic methods for inflammatory diseases such as Sjogren's syndrome and age-related dysfunctions.     

Short‐Term Effects of Non‐Surgical Periodontal Treatment on the Gingival Crevicular Fluid Cytokine Profiles in Sites With Induced Periodontal Defects: A Study on Dogs With and Without Streptozotocin‐Induced Diabetes

Background: The aim of this study is to assess the short‐term effects of non‐surgical periodontal therapy (NSPT) on the gingival crevicular fluid (GCF) cytokine profile in sites with standardized periodontal bony defects in beagle dogs with and without diabetes. Methods: Four beagle dogs with streptozotocin (STZ)‐induced diabetes and four healthy dogs were included. Fasting blood glucose levels were measured using a glucometer. In all animals, a 3‐walled bony defect was created on the mesial surface of the second premolar and first molar in all quadrants. After 12 weeks, all animals underwent weekly NSPT for 3 weeks. Baseline and post‐NSPT GCF samples were collected, and levels of interleukin (IL)‐1, IL‐1β, IL‐6, IL‐8, and tumor necrosis factor (TNF)‐α were measured using enzyme‐linked immunosorbent assay. Statistical analyses were performed using a software program, and P values <0.05 were considered statistically significant. Results: Mean fasting blood glucose levels were significantly higher in dogs with induced diabetes than those without diabetes (P <0.01). At baseline, mean IL‐6 (P <0.01) and IL‐8 (P <0.05) levels were higher in dogs with diabetes than those without diabetes. A significant reduction in levels of IL‐1, IL‐1β, IL‐6, IL‐8, and TNF‐α was noted in dogs without diabetes 1 week after NSPT. However, this significant reduction (P <0.05) only appeared 2 weeks after NSPT in dogs with diabetes. Conclusions: NSPT reduces GCF levels of proinflammatory cytokines in dogs with and without STZ‐induced diabetes; however, chronic hyperglycemia seems to retard the effect of NSPT on GCF cytokine concentration.     

Cytokines,matrix metalloproteinases and tissue inhibitor of metalloproteinases‐1 in gingival crevicular fluid from patients with Papillon‐Lefèvre syndrome

The aim of the present study was to compare concentrations of cytokines, matrix metalloproteinases (MMPs) and a metalloproteinase inhibitor (TIMP‐1) in gingival crevicular fluids (GCF) from sites with gingival inflammation in 28 young patients with Papillon‐Lefèvre syndrome (PLS), and in age‐ and gender‐matched controls. Each group consisted of 17 females and 11 males with a mean age of 11.0 years (range 4–22 years). In both groups, anterior upper sites with a clinical diagnosis of gingival inflammation and with pockets ≤3?mm were selected for sampling of GCF, which was carried out with filter disks inserted into the gingival crevice until saturated. The concentrations of cytokines (IL‐1α, IL‐1β, TNF‐α, and IL‐8), matrix metalloproteinases (MMP‐1, MMP‐3, MMP‐8, and MMP‐9), and their tissue inhibitor (TIMP‐1) were analysed using commercial ELISA kits. Significantly higher levels of IL‐1β (P?P?P?P?P?相似文献   

Blocking Proinflammatory Cytokine Release Modulates Peripheral Blood Mononuclear Cell Response to Porphyromonas gingivalis

Background: Chronic periodontitis (CP) is an inflammatory disease in which cytokines play a major role in the progression of disease. Anti‐inflammatory cytokines (interleukin 4 [IL‐4] and IL‐10) were reported to be absent or reduced in diseased periodontal tissues, suggesting an imbalance between the proinflammatory and anti‐inflammatory mediators. This study tests the hypothesis that there is cellular crosstalk mediated by proinflammatory and anti‐inflammatory cytokines and that blocking proinflammatory cytokine (tumor necrosis factor‐α [TNF‐α] and IL‐1) production will enhance anti‐inflammatory cytokine (IL‐4 and IL‐10) production from peripheral blood mononuclear cells (PBMCs) in response to Porphyromonas gingivalis. Methods: PBMCs were isolated from individuals diagnosed with CP or healthy individuals and cultured for 24 hours. Concanavalin A (ConA) was used as an activator of lymphocyte function. Live and heat‐killed P. gingivalis or lipopolysaccharide from P. gingivalis were used as the bacterial stimulants. TNF‐α and IL‐1 production was neutralized by specific antibodies against TNF‐α and IL‐1α or IL‐β. Culture supernatants were evaluated by enzyme‐linked immunosorbent assay for TNF‐α, IL‐1β, IL‐4, and IL‐10 production. Results: Live P. gingivalis did not result in any significant IL‐10 or IL‐4 release, whereas heat‐killed P. gingivalis led to a significant increase in IL‐10 levels compared with unstimulated or live P. gingivalis–stimulated cells from both healthy individuals or those with CP. Overall, PBMCs from patients with CP produced significantly lower IL‐10 in response to ConA and P. gingivalis, suggesting chronic suppression of the anti‐inflammatory cytokine production. Blocking the proinflammatory cytokine response did not result in any substantial change in IL‐10 or IL‐4 response to live P. gingivalis. Blocking the proinflammatory cytokine response restored IL‐10 production by cells from CP in response to P. gingivalis lipopolysaccharide. Conclusions: These findings suggest that PBMCs from patients with CP have suppressed anti‐inflammatory cytokine production that can, in part, be restored by neutralizing proinflammatory cytokines. Monocytes are an important source of IL‐10 production, and monocyte‐derived IL‐10 might play a regulatory role in the pathogenesis of CP.     

Is There an Interaction Between Polycystic Ovary Syndrome and Gingival Inflammation?

Background: The aim of this study is to evaluate the gingival crevicular fluid (GCF), saliva, and serum concentrations of tumor necrosis factor‐α (TNF‐α), TNF‐α receptor‐1 (TNF‐αR1), TNF‐αR2, and interleukin‐6 (IL‐6) in non‐obese females with polycystic ovary syndrome (PCOS) and either clinically healthy periodontium or gingivitis. Methods: Thirty‐one females with PCOS and healthy periodontium, 30 females with PCOS and gingivitis, and 12 systemically and periodontally healthy females were included in the study. GCF, saliva, and serum samples were collected, and clinical periodontal measurements, body mass index, and Ferriman‐Gallwey score (FGS) were recorded. Sex hormones, cortisol, and insulin levels were measured. TNF‐α, TNF‐αR1, TNF‐αR2, and IL‐6 were determined by enzyme‐linked immunosorbent assay. Kruskal‐Wallis followed by Bonferroni‐corrected post hoc Mann‐Whitney U tests were used to analyze the data. Results: The PCOS + gingivitis group revealed significantly higher GCF, saliva, and serum IL‐6 concentrations than the PCOS + healthy group (P <0.0001). The two PCOS groups exhibited significantly higher saliva TNF‐α concentrations than the control group (P = 0.024 and P = 0.013, respectively). The FGS index was significantly higher in the PCOS + gingivitis group than the PCOS + healthy group (P = 0.030). The PCOS + gingivitis group revealed significantly higher insulin concentration than the PCOS + healthy and control groups (P = 0.014 and P <0.0001, respectively). Serum TNF‐α, TNF‐αRs, and serum, GCF, and salivary IL‐6 levels correlated with the clinical periodontal measurements. Conclusions: PCOS and gingival inflammation appear to act synergistically on the proinflammatory cytokines IL‐6 and TNF‐α. Thus, PCOS may have an impact on gingival inflammation or vice versa. Additional studies are warranted to clarify the possible relationship between PCOS and periodontal disease.     

Cytokines in healthy temporomandibular joint synovial fluid

Analysis of temporomandibular joint (TMJ) synovial fluid may elucidate the aetiology of temporomandibular disorders and arthritic conditions, as well as the inflammatory mechanisms involved. Knowledge about healthy synovial fluid is necessary to understand TMJ pathologies. We aimed to quantify the proinflammatory cytokines interleukin (IL)‐1β, IL‐2, IL‐6 and tumour necrosis factor (TNF), and the anti‐inflammatory cytokines IL‐10 and interferon (IFN)‐γ in healthy TMJ synovial fluid to serve as reference values for future studies on TMJ pathologies. Twenty healthy, young adult volunteers without temporomandibular dysfunction were included. Bilateral synovial fluid samples were obtained using the push‐pull technique with hydroxocobalamin described by Alstergren in 1999. Cytokines were quantified with Luminex multiplex assays and compared using nonparametric statistical analysis. No serious adverse effects were reported. Of 40 possible samples, 14 fulfilled the strict sampling criteria and were included in the analysis. Cytokine values (reported as medians with interquartile ranges) were as follows: TNF, 23 (13–37) pg mL^?1; IL‐2, 1·8 (0–22) pg mL^?1; and INF‐γ, 10 (0–47) pg mL^?1. IL‐1β, IL‐6 and IL‐10 were almost undetectable. In addition, TNF and INF‐γ cytokine levels correlated. We demonstrated that TNF was consistently detected and IFN‐γ and IL‐2 sporadically detected in the TMJ synovial fluid of healthy individuals using the hydroxocobalamin method and a multiplex assay. The cytokines IL‐10, IL‐1β and IL‐6 were barely detectable in this sample of healthy TMJs.     

Saliva and Serum Levels of B‐Cell Activating Factors and Tumor Necrosis Factor‐α in Patients With Periodontitis

Background: B‐lymphocytes play a central and critical role in the adaptive immune response against invading pathogens. This study evaluates saliva and serum levels of APRIL (a proliferation‐inducing ligand), B‐cell activating factor (BAFF), tumor necrosis factor‐α (TNF‐α), interleukin (IL)‐6, and IL‐10 in patients with chronic periodontitis (CP) or aggressive periodontitis (AgP) and periodontally healthy individuals. Methods: Twenty‐five patients with AgP, 20 patients with CP, and 20 periodontally healthy individuals were included. Smoking status was recorded, and all individuals were divided into non‐smokers and smokers. Saliva and serum samples were collected before clinical periodontal measurements. APRIL, BAFF, TNF‐α, IL‐6, and IL‐10 levels in serum and saliva samples were determined by enzyme‐linked immunosorbent assay. Statistical analysis was performed using multivariate analysis of variance and bivariate correlation. Results: Serum and saliva levels of TNF‐α, APRIL, BAFF, IL‐6, and IL‐10 were similar in CP and AgP groups. Serum levels of TNF‐α, APRIL, and BAFF and saliva levels of BAFF were significantly higher in periodontitis groups than healthy controls (P <0.05). Non‐smokers with CP or AgP had lower levels of saliva TNF‐α and APRIL and serum APRIL and IL‐6 than smokers with CP or AgP (P <0.05). Saliva APRIL and serum TNF‐α and IL‐6 levels were significantly higher in healthy smokers than healthy non‐smokers (P <0.05). Clinical periodontal parameters correlated positively with TNF‐family cytokines and negatively with IL‐10 (P <0.05). Conclusions: Within the limits of this study, it may be suggested that elevated salivary and serum TNF‐α, APRIL, and BAFF in patients with periodontitis may contribute to the dominance of B cells in periodontitis lesions. Moreover, higher levels in healthy smokers than non‐smoking counterparts may play a role in detrimental effects of smoking on periodontal tissues.     

Microbiology and cytokine levels around healthy dental implants and teeth

Background: Elicitation of the relationship of periodontopathogens and pro‐inflammatory cytokines to bone resorption and formation is significant to a growing body of research known as osteoimmunology. It is essential that clinically healthy peri‐implant and periodontal sites are studied to contribute comparison data for investigations that are addressing diseased sites. Purpose: The purpose of this study was to describe levels of selected pro‐inflammatory cytokines in clinically healthy peri‐implant and periodontal sites, and to examine whether cytokine levels may be related to specific bacterial/viral pathogens. Materials and Methods: Eleven subjects (mean age 56.2 ± 10) participated in the study. Subgingival microbial samples were cultured for periodontopathic bacteria. Gingival crevicular fluid samples were analyzed by nested polymerase chain reaction for Cytomegalovirus (HCMV) and were tested for the quantification of Interleukin (IL)‐8, IL‐1β, IL‐6, IL‐10, Tumor Necrosis Factor (TNF)‐α, and IL‐12p70 using flow cytometry (FACS). Findings for microbiota composition and cytokine levels were compared between implants and teeth (chi square, Kruskall–Wallis, Mann–Whitney; p ≤ .05). Results: Both the frequency (%) and levels (%) of periodontopathic bacteria were higher around teeth than implants. The concentration (picogram per milliliter) of cytokines was more prominent around implants than teeth, reaching nearly twofold differences in some instances. Cytokine levels were higher when the sites analyzed were positive for any bacteria tested. HCMV was not detected. Conclusions: Pro‐inflammatory cytokine production was unrelated to heavy bacterial challenge. Nevertheless, when periodontopathic bacteria were detected by culture, cytokine levels were increased around both implants and teeth. Studies are needed to investigate the pro‐inflammatory cytokines (especially IL‐1β and TNF‐α) produced in spite of minimal bacterial accumulation.     

Burning mouth syndrome and saliva: detection of salivary trace elements and cytokines

Background: Burning mouth syndrome (BMS) is considered a syndrome with an unknown cause. Roles of various trace elements and cytokines in saliva have been implicated in the development of BMS. The aim of the present study was to compare the levels of salivary trace elements [magnesium (Mg), zinc (Zn), copper (Cu)] and interleukin (IL)‐2 and IL‐6, and to search for a correlation between depression/anxiety and salivary trace elements and cytokines in BMS patients and controls. Methods: Thirty patients with BMS and 30 matched healthy controls participated in the study. Unstimulated saliva was collected from participants and salivary flow rates were determined. Mg, Zn and Cu levels were determined by atomic absorbance spectrophotometry. Cytokine immunoassay kits were used to determine the concentration of IL‐2 and IL‐6 in the whole saliva samples. Anxiety and depression were analyzed by means of the Speilberger State‐Trait Anxiety Inventory (SAI‐TAI) and Zung Self‐Rating Depression Scale. Results: Although subjects in the control group had significantly higher mean levels for Mg compared with BMS patients (P < 0.01), no statistically significant differences were observed in relation to Zn and Cu levels between the two groups (P < 0.001). There were no statistically significant differences in IL‐2 and IL‐6 levels of BMS and control groups, but subjects in BMS group had slightly, not significantly, higher mean levels for IL‐6 compared with controls. Subjects in BMS group had significantly higher mean values for TAI compared with controls (P < 0.05). There were no statistically significant differences in relation to salivary levels of Mg, Zn, Cu, IL‐2, IL‐6 and depression/anxiety between BMS and control groups. Conclusions: The results of our study indicate that Mg levels could have an impact on symptoms of BMS and further studies are necessary to determine the importance of cytokines in the pathogenesis of BMS.     

The role of IL‐6 on apical periodontitis: a systematic review

The aim of this review was to examine current knowledge of the role of interleukin‐6 (IL‐6) in apical periodontitis (AP) pathogenesis as an inflammatory or pro‐inflammatory cytokine. It also looked at whether IL‐6 could serve as a measure for differential diagnosis or as a biomarker that can further predict the progression of bone resorption. A systematic review relating to AP and IL‐6 was made via PubMed, BIOSIS, Cochrane, EMBASE and Web of Science databases using keywords and controlled vocabulary. Two independent reviewers first screened titles and abstracts and then the full texts. The reference lists of the identified publications were examined for additional titles. Eighteen papers were studied in total. In vitro studies (n = 6) revealed that IL‐6 is present in AP, and its levels are proportional to the size of the periapical lesions. Neutrophils and macrophages resident in these lesions can produce IL‐6 in vitro after a bacterial stimulus. Animal studies (n = 5) showed that IL‐6 is present in AP and that osteoblasts can produce IL‐6 in vivo. On the other hand, two studies using IL‐6 knockout mice revealed larger periapical lesions when compared with control groups, demonstrating IL‐6's role as an anti‐inflammatory cytokine. In human studies (n = 7), IL‐6 was identified in AP, and its levels were higher in symptomatic, epithelialized and large lesions than in asymptomatic and small lesions. These data lead to the conclusion that IL‐6 may play a pro‐inflammatory role, increasing its levels and reabsorbing bone in the presence of infections. When IL‐6 is not present, other cytokines such as IL‐1 and TNF‐α induce bone resorption. Further studies about the relationship between AP development and the cytokine network must be performed to establish the exact role of each cytokine in the inflammatory process.     

Hepatocytes produce tumor necrosis factor-α and interleukin-6 in response to Porphyromonas gingivalis

Takano M, Sugano N, Mochizuki S, Koshi RN, Narukawa TS, Sawamoto Y, Ito K. Hepatocytes produce tumor necrosis factor‐α and interleukin‐6 in response to Porphyromonas gingivalis. J Periodont Res; 2012; 47: 89–94. © 2011 John Wiley & Sons A/S Background and Objective: The liver plays a major role in clearing systemic bacterial infections. In addition, inflammatory cytokines produced in the liver play a critical role in systemic cytokine levels. The aim of this study was to investigate the production of tumor necrosis factor‐α (TNF‐α) and interleukin‐6 (IL‐6) by hepatocytes in response to periodontal pathogens. Material and Methods: The mouse hepatic carcinoma cell line Hepa‐1.6 and the mouse macrophage‐like cell line RAW 264 were co‐cultured in Transwell insert plates. Cells were stimulated with bacterial extracts prepared from Porphyromonas gingivalis and the induction of TNF‐α and IL‐6 was measured using real‐time PCR and ELISA. Results: After stimulation with bacteria, the induction of TNF‐α and IL‐6 was observed in RAW 264 cells and Hepa‐1.6 cells. Significant reduction of TNF‐α mRNA expression in Hepa‐1.6 cells was observed after treatment with antibody to TNF‐α. Conclusion: The results obtained in the present study show that P. gingivalis extract induces TNF‐α and IL‐6 in an in vitro liver model and that macrophage‐derived TNF‐α mediates the induction of TNF‐α in hepatocytes.     

Proinflammatory and Anti‐Inflammatory Cytokines in Gingival Crevicular Fluid and Serum of Patients With Rheumatoid Arthritis and Patients With Chronic Periodontitis

Background: The aim of this study is to evaluate proinflammatory and anti‐inflammatory cytokine levels in gingival crevicular fluid (GCF) and serum of rheumatoid arthritis (RA) and chronic periodontitis (CP) patients to assess whether cytokine profiles distinguish patients with RA and patients with CP while using healthy patients as background controls. Methods: A total of 49 patients, 17 patients with RA (three males and 14 females; mean age: 47.82 ± 10.74 years), 16 patients with CP (10 males and six females; mean age: 44.00 ± 7.00 years), and 16 controls (eight males and eight females; mean age: 28.06 ± 6.18 years) were enrolled. Patients with RA were under the supervision of rheumatologists; 15 of the patients with RA were being treated with methotrexate–sulfasalazine combined therapy, and two of the patients were being treated with leflunomid therapy. Periodontal parameters (plaque index, gingival index, probing depth, and clinical attachment level) were recorded. Interleukin (IL)‐1β, IL‐4, IL‐10, and tumor necrosis factor‐α (TNF‐α) were determined in GCF and IL‐1β and IL‐10 in serum by enzyme‐linked immunosorbent assay. Results: There were significant differences found among RA, CP, and control groups for all periodontal parameters (P <0.05). The total amount and concentration of GCF IL‐1 β, IL‐4, IL‐10, and TNF‐α were similar in RA and CP patients (P >0.05). Although the total amount and concentration of serum IL‐10 was not significantly different among the groups (P >0.05), serum IL‐1β was significantly lower in the RA group compared to CP patients and controls and was higher in GCF of the RA group compared to the CP group. Conclusions: Although clinical periodontal disease parameters indicated more severe periodontal disease in CP compared to RA patients, immunologic evaluation did not reveal consistent results regarding proinflammatory and anti‐inflammatory cytokine levels. This might be a result of the use of non‐steroidal anti‐inflammatory drugs and rheumatoid agents by patients with RA.     

Kinetics of Th17‐related cytokine expression in experimentally induced rat periapical lesions

Th17‐related cytokines are essential factors in various pathological states, including inflammatory bone destruction. This study investigated the contribution of Th17‐related cytokines to the progress of experimentally induced rat periapical lesions. Periapical pathoses were induced by unsealed exposure of the pulp chamber of the lower first molars. A variety of immunocompetent cells, including CD68⁺ macrophages, Ia antigen⁺ cells and TCRαβ⁺ T cells, were observed in the lesions. The expression levels of Th17‐related cytokines, IL‐17 and IL‐23, and of pro‐inflammatory cytokines, IL‐1β and IL‐6, were significantly increased at 14 days (expansion stage) compared with normal periapical tissues. The expression levels of Foxp3, a regulatory T cell (Treg)‐related gene, and of IL‐10, an anti‐inflammatory cytokine, were higher at 28 days (chronic stage) than at 14 days. These findings suggest that Th17‐related cytokines may be primary contributors to the initiation of periapical bone destruction, and that lesion expansion may be regulated by anti‐inflammatory mediators.     

A Cross‐Sectional Assessment of Biomarker Levels Around Implants Versus Natural Teeth in Periodontal Maintenance Patients

Background: Recent studies point to the clinical utility of using peri‐implant sulcular fluid (PISF) as a valuable diagnostic aid for monitoring peri‐implant tissue health. The objectives of this study are to determine the levels of key biomarkers in PISF in periodontal maintenance participants and compare them with their corresponding levels in gingival crevicular fluid (GCF) obtained from the same participants. Methods: PISF and GCF were collected from an implant and a contralateral natural tooth after the clinical examination of 73 participants. The levels of interleukin (IL)‐1α, IL‐1β, IL‐6, IL‐8, IL‐10, IL‐12, IL‐17A, tumor necrosis factor (TNF)‐α, C‐reactive protein, osteoprotegerin, leptin, and adiponectin were determined using multiplex proteomic immunoassays. The correlation of biomarker concentrations between GCF versus PISF, within GCF or PISF, and with several covariates (age, brushing frequency, days since professional cleaning, probing depth [PD], and plaque index) were also determined. Results: Significantly higher levels of IL‐17A (P = 0.02) and TNF‐α (P = 0.03) were noted in PISF when compared with their levels in GCF. Significant positive correlations were noted between the concentrations of cytokines in PISF versus their levels in GCF. Among the covariates, a significant positive correlation was noted between mean PDs around implants and levels of IL‐1β (P <0.05) and IL‐8 (P <0.05) in PISF. Conclusion: The results of this study point to the differential expression of specific biomarkers in GCF versus their levels in PISF in periodontal maintenance patients, which is critical information before establishing PISF as a diagnostic fluid to monitor peri‐implant health.     

Effect of nonsurgical periodontal therapy on serum and gingival crevicular fluid cytokine levels during pregnancy and postpartum

Background and Objective: A low‐grade systemic inflammatory status originating from periodontal infection has been proposed to explain the association between periodontal disease and systemic conditions, including adverse obstetric outcomes. The aim of this study was to evaluate the effect of periodontal therapy during pregnancy on the gingival crevicular fluid and serum levels of six cytokines associated with periodontal disease and preterm birth. Material and Methods: A subsample of 60 women (18–35 years of age) up to 20 gestational weeks, previously enrolled in a larger randomized clinical trial, was recruited for the present study. Participants were randomly allocated to receive either comprehensive nonsurgical periodontal therapy before 24 gestational weeks (n = 30, test group) or only one appointment for supragingival calculus removal (n = 30, control group). Clinical data, and samples of blood and gingival crevicular fluid, were collected at baseline, at 26–28 gestational weeks and 30 d after delivery. The levels of interleukin (IL)‐1β, IL‐6, IL‐8, IL‐10, IL‐12p70 and tumor necrosis factor‐α were analyzed by flow cytometry. Results: After treatment, a major reduction in periodontal inflammation was observed in the test group, with bleeding on probing decreasing from 49.62% of sites to 11.66% of sites (p < 0.001). Periodontal therapy significantly reduced the levels of IL‐1β and IL‐8 in gingival crevicular fluid (p < 0.001). However, no significant effect of therapy was observed on serum cytokine levels. After delivery, the levels of IL‐1β in the gingival crevicular fluid of the test group were significantly lower than were those in the control group (p < 0.001), but there were no significant differences between test and control groups regarding serum cytokine levels. Conclusion: Although periodontal therapy during pregnancy successfully reduced periodontal inflammation and gingival crevicular fluid cytokine levels, it did not have a significant impact on serum biomarkers.     

Salivary flow rate and clinical characteristics of patients with xerostomia according to its aetiology

Summary The purpose of the present study was to investigate the differences in salivary flow rates and dry mouth‐related subjective symptoms and behaviours in patients with xerostomia according to its aetiology. One hundred and forty patients (24 men and 116 women, mean age, 58·1 ± 13·3 years) with a chief complaint of xerostomia were included. The patients were divided into five groups; Sjögren’s syndrome (n = 34), post‐radiation therapy in the head and neck region (n = 16), antipsychotic medications (n = 30), systemic diseases or medications affecting salivary flow (n = 35), and unknown aetiology (n = 25). The patients were asked a standardized series of questions concerning dry mouth, and their whole salivary flow rates were measured. Patients with a history of radiation therapy displayed the most decreased values of salivary flow rates and the most severe associated symptoms and behaviours while patients with unknown aetiology displayed the least decreased values of salivary flow rates and relatively favourable symptoms and behaviours. A burning sensation in the mouth was the most prevalent in patients with systemic diseases or those who were taking medications while altered taste perception was the most prevalent in patients taking antipsychotics. In conclusion, patients with xerostomia displayed various degrees of discomfort related to the quality of life according to the aetiology of their conditions.