Systemic inflammatory burden and local inflammation in periodontitis: What is the link between inflammatory biomarkers in serum and gingival crevicular fluid?

A Study Into Systemic and Oral Levels of Proinflammatory Biomarkers Associated With Endpoints After Active Non-Surgical Periodontal Therapy

AIM

To analyse whether some selected inflammatory biomarkers collected from venous blood and gingival crevicular fluid (GCF) were associated with the outcome of non-surgical periodontal therapy.

MATERIALS AND METHODS

Two-hundred and nine patients affected by periodontitis were enrolled in the study, who had undergone steps I and II therapy as well as a non-surgical re-instrumentation (NSRI) of periodontal pockets after 6 months. Serum (SE), plasma (PL) and GCF samples were quantitatively analysed for the following inflammatory biomarkers: active matrix metalloproteinase-8 (aMMP-8), prostaglandin E2 (PGE2) and surfactant protein D (SP-D). Therapy outcomes were evaluated using a 'treat-to-target' endpoint (T2T) at the patient level, defined as ≤ 4 sites with pocket depth ≥ 5 mm.

RESULTS

Patients presented with 23 ± 6 teeth (mean ± SD) at baseline. After steps I and II therapy, 41.6% of the patients reached T2T and after NSRI 47.4%. Univariate analysis identified a potential association between high levels of PL-SP-D and more favourable treatment outcomes. Multivariate binary logistic regression adjusted for sex, mean baseline probing depth, diabetes and current smoking status confirmed an independent relationship between baseline PL-SP-D and the T2T after steps I and II therapy (aOR 0.432, p = 0.011), implying that a higher level PL-SP-D at baseline is associated with a > 50% reduced risk of failing T2T. However, no such association was found for PL-SP-D and NSRI.

CONCLUSION

Higher baseline PL-SP-D levels might be associated with more favourable treatment outcomes after steps I and II therapy. This may be due to its role in the regulation of neutrophil function. However, further investigation is required to confirm this hypothesis. If proven, PL-SP-D could play a role as a biomarker for identifying individuals who respond differentially to primary therapy.

Daily activities and suspected dementia among community-dwelling older adults: a cross-sectional study

BACKGROUND

Dementia is undiagnosed among many older adults, and more than half the people in local communities live with symptoms of dementia are not properly treated.

OBJECTIVE

The study aims to explore the relationship between decline of daily activities and the incidence of suspected dementia.

METHODS

A two-stage sampling method was used to conduct a multicenter cross-sectional survey. Older adults who have not been diagnosed as dementia were recruited from the local community. The Revised Hasegawa Dementia Scale (HDS-R) was used to evaluate the cognitive function. We evaluated daily activities from several aspects (bathing, dressing, toileting, grooming, feeding, transportation, walking, telephone, housekeeping, and taking medications). Logistic regression was adopted to assess the influence of daily activities on the risk of suspected dementia after controlling for the covariates.

RESULTS

The analysis included 2458 individuals. Daily activities included toileting (OR = 1.830, 95%CI 1.581 ~ 2.119), grooming (OR = 1.938, 95%CI 1.659 ~ 2.265), dressing (OR = 1.771, 95%CI 1.542 ~ 2.033), bathing (OR = 1.793, 95%CI 1.591 ~ 2.022), feeding (OR = 1.821, 95%CI 1.565 ~ 2.118), transportation (OR = 1.996, 95%CI 1.743 ~ 2.285), walking (OR = 2.069, 95%CI 1.685 ~ 2.542), telephone (OR = 3.640, 95%CI 2.738 ~ 4.838), housekeeping (OR = 1.415, 95%CI 1.213 ~ 1.649), and taking medications (OR = 1.633, 95%CI 1.451 ~ 1.839) were still related to the incidence of suspected dementia after controlling for age, education, post-retirement work, social activity, drinking, smoking, living with spouses, and diabetes.

CONCLUSIONS

Daily activities were related to the incidence of suspected dementia. Daily activities were affected even if the older adults were not diagnosed as dementia. Timely and accurate diagnosis of dementia should be encouraged among community-dwelling older adults.

Preclinical Validation of MIN-T: A Novel Controlled-Released Formulation for the Adjunctive Local Application of Minocycline in Periodontitis

Background: Adjunctive treatment of periodontitis lacks solutions which allow for enough time for wound healing in the periodontal pockets by avoiding fast re-colonization. Such a solution might be an antibiotic-containing formulation with a controlled release over a period of weeks. Here, a recently described minocycline-containing approach is qualified for further clinical development by focusing on proof-of-concept, systemic burden, resistance development, and degradation studies. Methods: Animal studies were done in two different (mouse-chamber, rat Porphyromonas gingivalis challenging) models, including effects on inflammation markers, bone loss, and bone structure. Also, serum concentrations of minocycline after local application were determined by HPLC-MS/MS. The resistance status of bacterial clinical isolates against minocycline was investigated and the degradation of the formulation was characterized by laser scanning and scanning electron microscopy. Results: Animal studies clearly demonstrated the applicability of the new formulation in the investigated models. Inflammation markers decreased in a dose-dependent manner and reduced bone loss compared to non-treated group was observed. Therefore, the systemic burden of the antibiotic was neglectable. Minocycline is still effective against oral pathogens; resistance development was not seen. The biodegradable thread was first swollen and subsequently degraded over a period of weeks. Conclusions: The results support the continued clinical development of this new formulation. A phase I clinical trial is planned to further evaluate its safety and efficacy.

Periodontal disease: A systemic condition

For decades, periodontitis has been considered to be a local inflammatory disease of the periodontal tissues in the oral cavity. Initially, associations of periodontitis with a multitude of noncommunicable diseases were each studied separately, and relationships were shown. The associations of periodontitis with morbidities, such as cardiovascular diseases, rheumatoid arthritis, diabetes mellitus, respiratory diseases, have been demonstrated. As most such studies were cross-sectional in nature, questions about causality cannot be univocally answered. And periodontitis as an independent risk factor for one systemic disease, becomes even more difficult to assess since recently periodontitis has also been associated with multimorbidity. Periodontitis and many systemic diseases share environmental, lifestyle and genetic risk factors, and share immunopathology. Moreover, suffering from one common noncommunicable disease may increase the susceptibility for another such chronic disease; the systemic effects of one condition may be one of various risk factors for another such disease. The overarching effect of any systemic disease is it causing a pro-inflammatory state in the individual; this has also been shown for periodontitis. Moreover, in periodontitis a prothrombotic state and elevated immunological activity have been shown. As such, when we consider periodontal disease as another systemic disease, it can affect the susceptibility and progression of other systemic diseases, and importantly, vice versa. And with this, it is not surprising that periodontitis is associated with a variety of other noncommunicable diseases. The medical definition of a systemic disease includes diseases that affect different organs and systems. Thus, the aim of this opinion paper is to propose that periodontitis should be considered a systemic disease in its own right and that it affects the individual's systemic condition and wellbeing. The dental and medical profession and researchers alike, should adapt this paradigm shift, advancing periodontal disease out of its isolated anatomical location into the total of chronic noncommunicable diseases, being for some conditions a comorbid disease and, vice versa, comorbidities can affect initiation and progression of periodontal disease.

Comparative Evaluation of Salivary Cathelicidin and 8-Isoprostane Levels Among Smokeless Tobacco Users and Non-users and Their Correlation With Periodontal Health and Disease: A Cross-Sectional Study

Introduction Periodontal diseases arise from host-microbial interactions influenced by tobacco products. Salivary antimicrobial peptides such as salivary cathelicidin and prostaglandins such as 8-isoprostane are part of the inflammatory cascade affecting periodontal disease pathogenesis. Methodology A total of 93 patients, 31 in each group that is healthy, periodontitis, and periodontitis with smokeless tobacco habit patients, were enrolled. The case history was recorded, and clinical examination was performed using periodontal parameter analysis of oral hygiene index simplified (OHIS), Russell's index, periodontal pocket depth (PPD), and clinical attachment level (CAL). The saliva samples were collected and subjected to an enzyme-linked immunosorbent assay (ELISA) to evaluate cathelicidin and 8-isoprostane. The results were analysed and compared statistically. Results The OHIS, Russell's index, pocket probing depth, and CAL were high in patients with periodontitis and tobacco habit (p<0.001). The cathelicidin levels were the highest in patients with periodontitis and the tobacco habit (1.6 g/mL). The level of 8-isoprostane was the highest in patients with periodontitis with tobacco habit (1.8 pg/mL). Smokeless tobacco users showed higher levels of cathelicidin and 8-isoprostane in periodontitis with tobacco than in the healthy group. Conclusion Increased cathelicidin and 8-isoprostane levels in smokeless tobacco users with periodontitis suggest risk biomarkers for tobacco-influenced periodontitis.

Non-Surgical Periodontal Therapy's Influence on Alpha-Synuclein and Inflammatory Marker Levels: A Pilot Study

Background: Microbial dysbiosis may contribute to alpha-synuclein (α-Syn) homeostasis disruption, yet the burden of inflammatory periodontal infection and its treatment have never been studied in this regard. We aimed to compare the cytokine and α-Syn levels in the saliva and blood of patients with periodontitis who underwent non-surgical periodontal therapy (NSPT) and those of their healthy counterparts. Methods: Periodontal examination and saliva and blood sample collection were carried out in incoming patients at a university clinic. The periodontitis group (PG) received NSPT. The sample collection and periodontal observation were repeated 30 days after. IL-6, IL1-β and total α-Syn were quantified using immunoassay methods. The periodontal inflamed surface area (PISA) was calculated as a proxy for periodontal inflammation. Results: Eleven participants formed the PG, and there were fifteen healthy controls (HC). At baseline, no correlation between salivary and plasma α-Syn was found. The salivary α-Syn levels revealed a tendency to decrease 30 days after, particularly in the PD cases. The variation in PISA and α-Syn showed significant correlation. Salivary α-Syn correlated negatively with salivary IL-6 levels at both timepoints in the total sample (rho = -0.394 and rho = -0.451) and in the HC (rho = -0.632 and rho = -0.561). Variations in plasma IL-6 and α-Syn were negatively correlated (rho = -0.518) in the healthy participants. Baseline plasma IL1-β negatively correlated with plasmatic α-Syn at 30 days in the HC (rho = -0.581). Conclusions: Salivary and plasma α-Syn bioavailability operate independently, and periodontal diagnosis was not a confounding factor. Salivary α-Syn levels were significantly affected by NSPT, contrary to plasma levels. These results should be confirmed in future larger and prospective studies.

The association between vitamin D binding protein levels and periodontal status: A systematic review

BACKGROUND AND OBJECTIVES

Vitamin D binding protein (DBP) is biosynthesised in the liver and is predominantly expressed in serum. Its primary role centres on facilitating the systemic transportation of vitamin D and its metabolites, notably 25-hydroxyvitamin D, to specific target tissues where vitamin D exerts its biological functions. Due to the paucity of studies, it is unclear whether there is an association between DBP and periodontal status and thus its potential use as a diagnostic biomarker. Therefore, the aim of the systematic review is to investigate the association between DBP in periodontal disease.

METHODS

Two independent reviewers (YD and RG) performed a systematic literature search of English publications using several databases including MEDLINE (OVID interface, 1946 onwards), EMBASE (OVID interface, 1974 onwards), and Global Health (OVID interface, 1973 onwards). This search strategy enabled the identification of relevant publications and the development of a comprehensive library of studies. Studies were included based on previously agreed eligibility criteria. Of the eight studies included as part of this systematic review, seven were case-control studies and one was a cross-sectional study. The quality assessment was based on the Newcastle-Ottawa Scale (NOS) for case-control studies and the modified NOS for the cross-sectional study.

RESULTS

The NOS quality assessment was 'favorable' for 6 included case control studies; and 'fair' for one study. The modified NOS quality assessment for the single cross-sectional study demonstrated a medium risk of bias. The results of the majority of the included studies indicated a statistically significant higher concentration of DBP levels in individuals with periodontitis in comparison to those who were periodontally healthy. This trend held true irrespective of the sampling method employed for the assessment of DBP concentration.

CONCLUSION

The results summarised in this systematic review indicate a positive association between DBP and periodontitis. Nonetheless, there is a need for longitudinal, prospective trials, to confirm the use of DBP as a potential biomarker for the diagnosis of periodontitis.

Serum biomarker levels in smokers and non-smokers following periodontal therapy. A prospective cohort study

BACKGROUND

To compare presence and levels of serum cytokines in smokers and non-smokers with periodontitis following periodontal therapy.

METHODS

Thirty heavy smokers and 30 non-smokers with stage III or IV periodontitis were included in this prospective cohort study. Clinical data and blood serum were collected at baseline (T0), after step I-III (T1), and after 12 months step IV periodontal therapy (T2). Cytokine IL-1β, IL-6, IL-8, TNF-α, IL-10, and IP-10 levels were measured using multiplex kit Bio-Plex Human Pro™ Assay. Linear regression models with cluster robust variance estimates to adjust for repeated observations were used to test intra- and intergroup levels for each marker, IL-6 and IL-8 defined as primary outcomes.

RESULTS

Clinical outcomes improved in both groups following therapy (p < 0.05). IL-6 levels increased with 75.0% from T0-T2 among smokers (p = 0.004). No significant intra- or intergroup differences were observed for IL-8. Higher levels of TNF-α (44.1%) and IL-10 (50.6%) were detected in smokers compared with non-smokers at T1 (p = 0.007 and p = 0.037, respectively). From T1-T2, differences in mean change over time for levels of TNF-α and IL-10 were observed in smokers compared with non-smokers (p = 0.005 and p = 0.008, respectively).

CONCLUSION

Upregulated levels of serum cytokines in smokers indicate a systemic effect of smoking following periodontal therapy. Differences in cytokine levels between smokers and non-smokers demonstrate a smoking induced modulation of specific systemic immunological responses in patients with severe periodontitis.

Does smoking influence tryptophan metabolism in periodontal inflammation? A cross-sectional study

OBJECTIVES

The aim of this study was to identify the effects of smoking and periodontal inflammation on tryptophan-kynurenine metabolism as well as the correlation between these findings and clinical periodontal parameters.

BACKGROUND

It has been shown that the tryptophan amino acid's primary catabolic pathway, the kynurenine pathway (KP), may serve as a key biomarker for periodontal disease. Although there are studies investigating the effect of smoking on KYN-TRP metabolism, the effect of smoking on periodontal disease through KP has not been revealed so far.

METHODS

The salivary and serum samples were gathered from 24 nonsmoker (NS-P) stage III, grade B generalized periodontitis and 22 smoker (S-P) stage III, grade C generalized periodontitis patients, in addition to 24 nonsmoker (NS-C) and 24 smoker (S-C) periodontally healthy control individuals. Saliva and serum IL-6, kynurenine (KYN), and tryptophan (TRP) values, and KYN/TRP ratio were analyzed by liquid chromatography-mass spectrometry. Clinical periodontal measurements were recorded.

RESULTS

Salivary TRP values were significantly higher in both periodontitis groups than control groups (p < .05). Salivary KYN values were highest in NS-P group (p < .05). Salivary KYN values did not differ significantly between periodontitis groups (p = .84). Salivary KYN/TRP ratio was significantly lower in NS-P group compared to other groups (p < .001). Serum TRP value is higher in S-P group than other groups; however, significant difference was found in S-C group (p < .05). Serum KYN values were significantly lower in smokers than nonsmokers. Serum KYN/TRP ratio is higher in NS-P group. NS-P group has the highest salivary IL-6 levels, NS-C group has the lowest values (p < .05).

CONCLUSIONS

Our results point out that smoking exacerbates inflammation in the periodontium and increases TRP destruction and decreases IDO activity by suppressing KP in serum. As a result, kynurenine and its metabolites may be significant biomarkers in the link between smoking and periodontal disease.

Impact of an Okinawa/Nordic based diet on endocrinological and periodontal conditions in individuals with type 2 diabetes. A randomized case-control study

OBJECTIVES

To assess if the results following intake of a diet using an Okinawan-based Nordic diet (OBND) over one month differs in endocrinological, periodontal clinical outcome, and serum cytokine levels compared to a standard hospital care diet in individuals with diabetes type 2 (T2D) (control group).

BACKGROUND

Scientific evidence suggests that the use of diet for individuals with T2D may be beneficial.

METHODS

Participating individuals with T2D were randomly assigned to a test (OBND) (n = 14), or control group (n = 16). Anthropometric data, blood glucose levels, HbA1c levels, lipids, serum inflammation markers (CRP, and a routine panel of 24 cytokines), blood pressure, gingival bleeding on probing (BOP), probing pocket depths (PPD), and clinical attachment levels (CAL) were studied.

RESULTS

Statistical analyses of baseline study data failed to demonstrate study group differences. The mean weight reduction was greater in the OBND group (4.1 kg) versus the control group (1.3 kg) (p < 0.01). The reduction in BMI was 1.4 kg/m2 in OBND (p < 0.001) and 0.5 kg/m2 in the control group, respectively (p < 0.01). Diastolic and systolic blood pressure reductions were greater in the OBND group than in the control group (p < 0.01). Periodontal study parameters (BOP % scores) and (PPD values) decreased (p < 0.001) overall with no between group differences. The OBND resulted in reduction of serum levels of IFNγ, Eotaxin IL-9, IP10,IL17a, MCP-1,m and PDFBB compared to the control diet.

CONCLUSIONS

A strict T2D- diet provides an association between reduction in serum HbA1c and BOP scores. Serum levels decreases in IFNγ, Eotaxin IL-9, IP-10, IL17a. MCP-1, and PDFBB were only found in the test group.

Maladaptive trained immunity and clonal hematopoiesis as potential mechanistic links between periodontitis and inflammatory comorbidities

Periodontitis is bidirectionally associated with systemic inflammatory disorders. The prevalence and severity of this oral disease and linked comorbidities increases with aging. Here, we review two newly emerged concepts, trained innate immunity (TII) and clonal hematopoiesis of indeterminate potential (CHIP), which together support a potential hypothesis on how periodontitis affects and is affected by comorbidities and why the susceptibility to periodontitis and comorbidities increases with aging. Given that chronic diseases are largely triggered by the action of inflammatory immune cells, modulation of their bone marrow precursors, the hematopoietic stem and progenitor cells (HSPCs), may affect multiple disorders that emerge as comorbidities. Such alterations in HSPCs can be mediated by TII and/or CHIP, two non-mutually exclusive processes sharing a bias for enhanced myelopoiesis and production of innate immune cells with heightened proinflammatory potential. TII is a state of elevated immune responsiveness based on innate immune (epigenetic) memory. Systemic inflammation can initiate TII in the bone marrow via sustained rewiring of HSPCs, which thereby display a skewing toward the myeloid lineage, resulting in generation of hyper-reactive or "trained" myeloid cells. CHIP arises from aging-related somatic mutations in HSPCs, which confer a survival and proliferation advantage to the mutant HSPCs and give rise to an outsized fraction of hyper-inflammatory mutant myeloid cells in the circulation and tissues. This review discusses emerging evidence that supports the notion that TII and CHIP may underlie a causal and age-related association between periodontitis and comorbidities. A holistic mechanistic understanding of the periodontitis-systemic disease connection may offer novel diagnostic and therapeutic targets for treating inflammatory comorbidities.

Effect of the Mediterranean diet on gingivitis: A randomized controlled trial

AIM

This study aimed to investigate the effects of a 6-week Mediterranean diet (MD) intervention on gingival inflammatory and anthropometric parameters of patients with gingivitis.

MATERIALS AND METHODS

Forty-two participants were allocated to MD group (MDG) or control group (CG). After a 2-week equilibration period regarding dental care procedures, only MDG changed their diet to MD for 6 weeks, supported by a diet counselling. Gingival and anthropometric parameters were assessed at baseline (T0), Week 2 (T1, beginning of MD intervention), and Week 8 (T2). Adherence to MD was assessed by the Mediterranean Diet Adherence Screener (MEDAS); dietary behaviour was evaluated by the German Health Interview and Examination Survey for Adults Food Frequency Questionnaire (DEGS-FFQ).

RESULTS

Plaque values remained constant in both groups. Inflammatory periodontal and anthropometric parameters decreased in the MDG only (gingival index: T1 1.51 ± 0.21, T2 1.49 ± 0.24; bleeding on probing: T1 51.00 ± 14.65, T2 39.93 ± 13.74; body weight: T1 79.01 ± 15.62, T2 77.29 ± 17.00; waist circumference: T1 84.41 ± 10.1, T2 83.17 ± 10.47 (p < .05). MEDAS revealed a sufficient diet adherence for MDG.

CONCLUSION

Within this study, gingival inflammatory parameters were significantly reduced by MD, whereas plaque parameters remained constant. The diet counselling achieved sufficient adherence with beneficial changes in weight loss and waist circumference.

Periodontal Inflammation and Systemic Diseases: An Overview

Periodontitis is a common inflammatory disease of infectious origins that often evolves into a chronic condition. Aside from its importance as a stomatologic ailment, chronic periodontitis has gained relevance since it has been shown that it can develop into a systemic condition characterized by unresolved hyper-inflammation, disruption of the innate and adaptive immune system, dysbiosis of the oral, gut and other location's microbiota and other system-wide alterations that may cause, coexist or aggravate other health issues associated to elevated morbi-mortality. The relationships between the infectious, immune, inflammatory, and systemic features of periodontitis and its many related diseases are far from being fully understood and are indeed still debated. However, to date, a large body of evidence on the different biological, clinical, and policy-enabling sources of information, is available. The aim of the present work is to summarize many of these sources of information and contextualize them under a systemic inflammation framework that may set the basis to an integral vision, useful for basic, clinical, and therapeutic goals.

The oral microbiome: Role of key organisms and complex networks in oral health and disease

States of oral health and disease reflect the compositional and functional capacities of, as well as the interspecies interactions within, the oral microbiota. The oral cavity exists as a highly dynamic microbial environment that harbors many distinct substrata and microenvironments that house diverse microbial communities. Specific to the oral cavity, the nonshedding dental surfaces facilitate the development of highly complex polymicrobial biofilm communities, characterized not only by the distinct microbes comprising them, but cumulatively by their activities. Adding to this complexity, the oral cavity faces near-constant environmental challenges, including those from host diet, salivary flow, masticatory forces, and introduction of exogenous microbes. The composition of the oral microbiome is shaped throughout life by factors including host genetics, maternal transmission, as well as environmental factors, such as dietary habits, oral hygiene practice, medications, and systemic factors. This dynamic ecosystem presents opportunities for oral microbial dysbiosis and the development of dental and periodontal diseases. The application of both in vitro and culture-independent approaches has broadened the mechanistic understandings of complex polymicrobial communities within the oral cavity, as well as the environmental, local, and systemic underpinnings that influence the dynamics of the oral microbiome. Here, we review the present knowledge and current understanding of microbial communities within the oral cavity and the influences and challenges upon this system that encourage homeostasis or provoke microbiome perturbation, and thus contribute to states of oral health or disease.

Measuring Effects of Dietary Fiber on the Murine Oral Microbiome with Enrichment of 16S rDNA Prior to Amplicon Synthesis

The oral cavity houses a diverse consortium of microorganisms corresponding to specific microbial niches within the oral cavity. The complicated nature of sample collection limits the accuracy, reproducibility, and completeness of sample collection of the dentogingival microbiome. Moreover, large variability among human oral samples introduces inexorable confounds. Here, we introduce a method to study the dentogingival microbiome using a murine model that allows for greater control over experimental variability and permits collection of the dentogingival microbiome in an intact state and in its entirety.As an example of this approach, this chapter provides a workflow to explore the effect of dietary fiber consumption on the murine dentogingival microbiome . Mice are fed diets corresponding to Fiber, Sugar, Fiber + Sugar, and Control groups for 7 weeks. A whole-mandible extraction technique is described to isolate the mandibular dentogingival surfaces. 16S rRNA gene analysis is coupled with removal of unwanted host DNA amplification products to allow an investigation of the dental microbiome in the presence of increased fiber in terms of microbial taxonomic abundance and diversity.

Oral Dysbiosis and Inflammation in Parkinson's Disease

Background:

Oral microbiota has largely escaped attention in Parkinson’s disease (PD), despite its pivotal role in maintaining oral and systemic health.

Objective:

The aim of our study was to examine the composition of the oral microbiota and the degree of oral inflammation in PD.

Methods:

Twenty PD patients were compared to 20 healthy controls. Neurological, periodontal and dental examinations were performed as well as dental scaling and gingival crevicular fluid sampling for cytokines measurement (interleukine (IL)-1β, IL-6, IL-1 receptor antagonist (RA), interferon-γ and tumor necrosis factor (TNF)-α). Two months later, oral microbiota was sampled from saliva and subgingival dental plaque. A 16S rRNA gene amplicon sequencing was used to assess bacterial communities.

Results:

PD patients were in the early and mid-stage phases of their disease (Hoehn & Yahr 2–2.5). Dental and periodontal parameters did not differ between groups. The levels of IL-1β and IL-1RA were significantly increased in patients compared to controls with a trend for an increased level of TNF-α in patients. Both saliva and subgingival dental plaque microbiota differed between patients and controls. Streptococcus mutans, Kingella oralis, Actinomyces AFQC_s, Veillonella AFUJ_s, Scardovia, Lactobacillaceae, Negativicutes and Firmicutes were more abundant in patients, whereas Treponema KE332528_s, Lachnospiraceae AM420052_s, and phylum SR1 were less abundant.

Conclusion:

Our findings show that the oral microbiome is altered in early and mid-stage PD. Although PD patients had good dental and periodontal status, local inflammation was already present in the oral cavity. The relationship between oral dysbiosis, inflammation and the pathogenesis of PD requires further study.

Effect of chemically modified tetracycline-8 (CMT-8) on hematology, blood chemistry, cytokines and peripheral blood lymphocyte subsets of healthy dogs

Tetracyclines are antibiotics widely used in human and veterinary medicine. Effects on the immune system and inflammatory response, including effects on blood leukocytes proliferation and function and in cytokines synthesis, have been described. Chemically modified tetracyclines (CMT) have lost their antimicrobial activity, but maintain these other properties. This study analyzes the effect of chemically modified tetracycline-8 (CMT-8) on the evolution of complete blood count, blood chemistry, the mRNA expression of selected cytokines and peripheral blood lymphocyte subpopulations distribution in healthy dogs. CMT-8 at a dose of 10 mg/kg once daily was administered per os to six healthy dogs. A control group of five healthy dogs, living in the same conditions than dogs treated with CMT-8, received placebo with an identical therapeutic regimen. When given at the doses used in this study, no side effects of CMT-8 were detected, suggesting a good tolerance and a limited toxicity of the drug. Dogs treated with CMT-8 showed a gradual increase in mean corpuscular hemoglobin. The administration of CMT-8 in healthy dogs did not affect blood mRNA expression of IFN-γ, TNFα, IL-4, IL-6, IL-10, IL-12 p40 and IL-13. However, the lymphocytes expressing class II MHC on their surface decreased during the first two weeks of CMT-8 treatment and subsequently increased for the next three months. Considering the absence of antimicrobial properties of the drug, the effects of CMT-8 detected in this study seem to be unrelated to the classical antimicrobial activity attributed to tetracyclines.

Clinical, inflammatory and microbiological outcomes of full-mouth scaling with adjunctive glycine powder air-polishing: A randomized trial

AIM

To determine the effects of glycine powder air-polishing (GPAP) as an adjunct to full-mouth scaling and root planing (SRP) on clinical, inflammatory and microbiological outcomes in patients with untreated periodontitis.

MATERIALS AND METHODS

Forty-one patients were randomly assigned to the control group A (SRP) and test groups B1 (subgingival GPAP right after SRP) and B2 (subgingival GPAP right before SRP). Clinical examinations and sample collections (saliva, subgingival plaque, serum and gingival crevicular fluid) were performed at assessment visits and before therapies at clinical visits of baseline, 6-week and 3-month. C-reactive protein, IL-6 and TNF-α were assessed in serum and gingival crevicular fluid, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans and Fusobacterium nucleatum were measured in saliva and subgingival plaque.

RESULTS

Patients in control and test groups did not significantly differ by age, sex and disease severity at baseline. Participants in control and intervention groups had similar improvements in clinical parameters (PD, BOP, PLI and BI). All groups had a similar percentage of sites showing PD reduction of ≥2 mm between baseline and follow-up visits, with a few exceptions. Reduced C-reactive protein, IL-6 and TNF-α in serum were found after treatments.

CONCLUSION

Full-mouth SRP with and without GPAP resulted in largely similar clinical, inflammatory and microbiological outcomes in the care of untreated periodontitis.

A review of T helper 17 cell-related cytokines in serum and saliva in periodontitis

Periodontitis is a chronic inflammatory disease with a complex underlying immunopathology. Cytokines, as molecular mediators of inflammation, play a role in all stages of disease progression. T helper 17 (Th17) cells are thought to play a role in periodontitis. Th17 cell development and maintenance requires a pro-inflammatory cytokine milieu, with many of the cytokines implicated in the pathogenesis of periodontitis. Serum and saliva are easily accessible biofluids which can represent the systemic and local environment to promote the development of Th17 cells. Here we review human clinical studies that investigate IL-1β, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, IFN-γ, sCD40L and TNF-α in serum and saliva in periodontitis. We highlight their putative role in the pathogenesis of periodontitis and place them within a wider context of animal and other clinical studies.

Coniferyl Aldehyde Inhibits the Inflammatory Effects of Leptomeningeal Cells by Suppressing the JAK2 Signaling

Background

The brain is in many ways an immunologically and pharmacologically privileged site because of the blood-brain barrier (BBB). But for chronic peripheral inflammation, inflammatory signals can be transmitted from the peripheral system into the central nervous system (CNS) through multiple channels and result in neuroinflammation. Leptomeningeal cells that form the BBB can trigger one signaling pathway by releasing cytokines to transmit inflammatory signals. Besides, the Janus kinase (JAK) family may have a certain function in the activation of leptomeninges. In the present study, we try to use coniferyl aldehyde (CA), a natural anti-inflammatory phenolic compound, to inhibit this inflammatory process and elucidate the underlying molecular mechanisms.

Results

Secretion of proinflammatory cytokines (TNF-α, IL-1β, and IL-6) significantly increased after incubation with P. gingivalis. Moreover, TNF-α, IL-1β, and IL-6 levels were upregulated, and the JAK2 signaling was enhanced in leptomeningeal cells in a conditioned medium from activated macrophages, which leads to the immune response in microglia. However, this inflammatory effect of leptomeningeal cells was reversed by CA administration, accompanied by the decreased immune response in microglia. The western blot assay revealed that JAK2 phosphorylation was suppressed in leptomeningeal cells treated with CA.

Conclusions

This study demonstrates that activated macrophages by P. gingivalis markedly induce the release of proinflammatory cytokines (TNF-α, IL-1β, and IL-6) from leptomeningeal cells, thereby activating the JAK2 signaling pathway and subsequently enhancing immune responses in microglia in the CNS. CA effectively inhibits the inflammatory effect of leptomeningeal cells via suppressing the JAK2 signaling pathway.

Efficacy of non-surgical treatment accompanied by professional toothbrushing in the treatment of chronic periodontitis in patients with type 2 diabetes mellitus: a randomized controlled clinical trial

Purpose

The present study aimed to evaluate the clinical benefit of additional toothbrushing accompanying non-surgical periodontal treatment on oral and general health in patients with type 2 diabetes mellitus (T2DM).

Methods

We conducted a doubled-blind randomized controlled trial in 60 T2DM patients between June 2013 and June 2014. The patients were randomly assigned to the scaling and root planing (SRP) group; the scaling and root planing with additional toothbrushing (SRPAT) group, in which additional toothbrushing was performed by toothpick methods; or the control group. Microbiological and oral examinations were performed for up to 12 weeks following treatment. Non-surgical treatment was conducted in the experimental groups. The SRP group received scaling and root planing and the SRPAT group received additional toothbrushing with the Watanabe method once a week from the first visit through the fifth visit. The primary outcomes were changes in haemoglobin A1c (or glycated haemoglobin; HbA1c) levels, serum endotoxin levels, and interleukin-1 beta levels. Periodontal health status was measured by periodontal pocket depth, the calculus index, and bleeding on probing (BOP).

Results

Both the SRP and SRPAT groups showed improvements in periodontal health and HbA1c, but the SRPAT group showed significantly less BOP than the SRP group. Furthermore, only the SRPAT group showed a statistically significant decrease in serum endotoxin levels.

Conclusions

Non-surgical periodontal treatment was effective in improving HbA1c and serum endotoxin levels in T2DM patients. Furthermore, non-surgical treatment with additional tooth brushing had a more favourable effect on gingival bleeding management.

Trial Registration

Clinical Research Information Service Identifier: KCT000416

Periodontitis Impact in Interleukin-6 Serum Levels in Solid Organ Transplanted Patients: A Systematic Review and Meta-Analysis

This systematic review aimed to investigate the influence of periodontitis on post-transplant IL-6 serum levels of solid organ transplanted patients as compared to healthy subjects. Four databases (PubMed, Scholar, EMBASE, and CENTRAL) were searched up to February 2020 (PROSPERO CRD42018107817). Case-control and cohort studies on the association of IL-6 serum levels with a periodontal status of patients after solid organ transplantation were included. The risk of bias of observational studies was assessed through the Newcastle-Ottawa Scale (NOS). Random effects meta-analyses were thoroughly conducted. GRADE assessment provided quality evidence. Four case-control studies fulfilled the inclusion criteria (274 transplant recipients and 146 healthy controls), all of low risk of bias. Meta-analyses revealed significantly higher IL-6 levels in transplanted patients than healthy individuals with low-quality evidence (Mean Difference (MD): 2.55 (95% confidence interval (CI): 2.07, 3.03)). Transplanted patients with periodontitis have higher serum IL-6 levels than transplanted patients without periodontitis with moderate quality evidence (MD: 2.20 (95% CI: 1.00, 3.39)). We found low-quality evidence of higher IL-6 levels than healthy patients in patients with heart and kidney transplant. In these transplanted patients, there was moderate quality evidence that periodontitis is associated with higher IL-6 serum levels. Future research should consider the impact of such a difference in organ failure and systemic complications.

Knowledge, Attitudes and Practice Behaviour of Midwives Concerning Periodontal Health of Pregnant Patients

Maternal gum disease is associated with adverse pregnancy outcomes such as preterm birth and low birthweight. This study aims to evaluate the knowledge, attitudes and practice behaviour of Australian midwives regarding the periodontal health of pregnant women to inform interprofessional antenatal care. This was an observational, cross-sectional study. We circulated an online questionnaire to Australian midwives from August 2018 to February 2019. Key outcome variables were knowledge, attitudes, and practice behaviours related to oral health. Key predictor variables were years of practice, practice location, and dental history. We summarized responses with frequency tables and assigned tallied scores for analysis using non-parametric statistical tests. 100 responses were analysed, including from rural (n = 23) and urban (n = 77) midwives. Eighty percent of midwives agreed that maternal dental care can positively affect pregnancy outcomes. Fluoridated toothpaste use (19.1%) was incorrectly answered to prevent gum disease more often than psychological stress control (7.9%), a correct answer. Rural midwives demonstrated a significantly higher knowledge score (p = 0.001) and significantly more positive practice behaviours towards oral health (p = 0.014) than urban midwives. Australian midwives have positive attitudes towards antenatal oral health but misunderstand gum disease aetiology and prevention. This study highlights areas to improve interprofessional education for optimal oral health and pregnancy outcomes.

PERIODONTAL DISEASE IN DIFFERENT STAGES OF CHRONIC KIDNEY DISEASE

Periodontal disease is a chronic multifactorial disease the worldwide incidence of which is higher than the incidence of caries and represents one of the leading problems in dental medicine. It is manifested by the loss of the attachment apparatus of the tooth and leads to the loss of teeth. Numerous studies have shown the association of periodontal disease and various chronic systemic diseases such as diabetes mellitus and cardiovascular disease. It is believed that low-grade level of chronic inflammation and release of bacterial toxins and inflammatory mediators in the bloodstream aggravate a chronic systemic disease. The purpose of our research was to investigate the possible association of periodontal disease and chronic kidney disease via the inflammatory cytokines path. In this cross-sectional study, we surveyed a total of 80 subjects divided into two groups. First group included subjects with chronic renal disease stages III and IV, and the second group included patients with chronic renal disease stage V that were on hemodialysis. We compared periodontal status, as well as serum levels of different cytokines, interleukin 6, interleukin 17A and tumor necrosis factor α between the two groups. The results showed no significant between-group differences in periodontal status, but interleukin 6 levels were significantly higher in the hemodialysis group of patients and were also associated with a poorer periodontal status.

The cytokine network involved in the host immune response to periodontitis

Periodontitis is an inflammatory disease involving the destruction of both soft and hard tissue in the periodontal region. Although dysbiosis of the local microbial community initiates local inflammation, over-activation of the host immune response directly activates osteoclastic activity and alveolar bone loss. Many studies have reported on the cytokine network involved in periodontitis and its crucial and pleiotropic effect on the recruitment of specific immunocytes, control of pathobionts and induction or suppression of osteoclastic activity. Nonetheless, particularities in the stimulation of pathogens in the oral cavity that lead to the specific and complex periodontal cytokine network are far from clarified. Thus, in this review, we begin with an up-to-date aetiological hypothesis of periodontal disease and summarize the roles of cytokines in the host immune response. In addition, we also summarize the latest cytokine-related therapeutic measures for periodontal disease.

Periodontal Disease in Patients Receiving Dialysis

Chronic kidney disease (CKD) is characterized by kidney damage with proteinuria, hematuria, and progressive loss of kidney function. The final stage of CKD is known as end-stage renal disease, which usually indicates that approximately 90% of normal renal function is lost, and necessitates renal replacement therapy for survival. The most widespread renal replacement therapy is dialysis, which includes peritoneal dialysis (PD) and hemodialysis (HD). However, despite the development of novel medical instruments and agents, both dialysis procedures have complications and disadvantages, such as cardiovascular disease due to excessive blood fluid and infections caused by impaired immunity. Periodontal disease is chronic inflammation induced by various pathogens and its frequency and severity in patients undergoing dialysis are higher compared to those in healthy individuals. Therefore, several investigators have paid special attention to the impact of periodontal disease on inflammation-, nutrient-, and bone metabolism-related markers; the immune system; and complications in patients undergoing dialysis. Furthermore, the influence of diabetes on the prevalence and severity of manifestations of periodontal disease, and the properties of saliva in HD patients with periodontitis have been reported. Conversely, there are few reviews discussing periodontal disease in patients with dialysis. In this review, we discuss the available studies and review the pathological roles and clinical significance of periodontal disease in patients receiving PD or HD. In addition, this review underlines the importance of oral health and adequate periodontal treatment to maintain quality of life and prolong survival in these patients.