Rheumatoid arthritis and periodontal disease

The role of MIF in periodontitis: A potential pathogenic driver, biomarker, and therapeutic target

OBJECTIVE

Periodontitis is an inflammatory disease that involves an imbalance in the oral microbiota, activation of inflammatory and immune responses, and alveolar bone destruction. Macrophage migration inhibitory factor (MIF) is a versatile cytokine involved in several pathological reactions, including inflammatory processes and bone destruction, both of which are characteristics of periodontitis. While the roles of MIF in cancer and other immune diseases have been extensively characterized, its role in periodontitis remains inconclusive.

RESULTS

In this review, we describe a comprehensive analysis of the potential roles of MIF in periodontitis from the perspective of immune response and bone regulation at the cellular and molecular levels. Moreover, we discuss its potential reliability as a novel diagnostic and therapeutic target for periodontitis.

CONCLUSION

This review can aid dental researchers and clinicians in understanding the current state of MIF-related pathogenesis, diagnosis, and treatment of periodontitis.

Neutrophils in Inflammatory Bone Diseases

PURPOSE OF REVIEW

In this review, we summarize the current evidence that suggests that neutrophils play a key role in facilitating damage to local bone structures.

RECENT FINDINGS

Neutrophil infiltration is a hallmark of inflammatory bone diseases such as rheumatoid arthritis (RA) and periodontitis disease (PD). Both of these human diseases are marked by an imbalance in bone homeostasis, favoring the degradation of local bone which ultimately leads to erosions. Osteoclasts, a multinucleated resident bone cell, are responsible for facilitating the turnover of bone and the bone damage observed in these diseases. The involvement of neutrophils and neutrophil extracellular trap formation have recently been implicated in exacerbating osteoclast function through direct and indirect mechanisms. We highlight a recent finding that NET proteins such as histones and elastase can generate non-canonical, inflammatory osteoclasts, and this process is mediated by post-translational modifications such as citrullination and carbamylation, both of which act as autoantigens in RA. It appears that NETs, autoantibodies, modified proteins, cytokines, and osteoclasts all ultimately contribute to local and permanent bone damage in RA and PD. However, more studies are needed to fully understand the role of neutrophils in inflammatory bone diseases.

The role of microbiota on rheumatoid arthritis onset

Rheumatoid arthritis (RA) is a chronic autoimmune disease that causes inflammation and pain, which can lead to the loss of normal joint function. Although the exact cause of the disease is not yet fully understood, both environmental factors and genetics may play a role in its development. Moreover, research suggests microbiota contributes to the onset and progression of RA. People with RA show higher quantities of bacteria such as Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella copri, Proteus mirabilis, and Lactobacillus salivarius compared to healthy individuals. Conversely, studies propose that Lactobacillus casei, a probiotic bacterium with immunomodulatory properties, has beneficial effects for RA in murine and human models. Therefore, this work reviews the potential role of the gut microbiota in the development of RA and explores the feasibility of using probiotic bacteria as a supplementary treatment for this disease.

The Relationship Between Porphyromonas Gingivalis and Rheumatoid Arthritis: A Meta-Analysis

Rheumatoid arthritis (RA) is a systematical autoimmune disease, characterized by chronic synovial joint inflammation and hurt. Porphyromonas gingivalis(P. gingivalis) can cause life-threatening inflammatory immune responses in humans when the host pathogenic clearance machinery is disordered. Some epidemiological studies have reported that P. gingivalis exposure would increase the prevalence of RA. However, the results remain inconsistent. Therefore, a meta-analysis was done to systematically analyze the relationship between P. gingivalis exposure and the prevalence of rheumatoid arthritis. Database including Cochrane Library, Web of Science, PubMed, and EMBASE were searched for published epidemiological articles assessed the relationship between P. gingivalis and RA. Obtained studies were screened based on the predefined inclusion and exclusion criteria. The overall Odds Ratios (ORs) of incorporated articles were pooled by random-effect model with STATA 15.1 software. The literature search returned a total of 2057 studies. After exclusion, 28 articles were included and analyzed. The pooled ORs showed a significant increase in the risk of RA in individuals with P. gingivalis exposure (OR = 1.86; 95% CI: 1.43-2.43). Subgroup analysis revealed that pooled ORs from populations located in Europe (OR = 2.17; 95% CI: 1.46-3.22) and North America (OR = 2.50; 95% CI: 1.23-5.08) were significantly higher than that from population in Asia (OR = 1.11; 95% CI: 1.03-1.20). Substantial heterogeneity was observed but did not significantly influence the overall outcome. In conclusion, our results indicated P. gingivalis exposure was a risk factor in RA. Prompt diagnosis and management decisions on P. gingivalis antimicrobial therapy would prevent rheumatoid arthritis development and progression.

B cell depletion in patients with rheumatoid arthritis is associated with reduced IL-1β in GCF

OBJECTIVES

We evaluated the effect of B cell depletion on the clinical periodontal findings and IL-1β and MMP-8 levels of the gingival crevicular (GCF) fluid in patients with rheumatoid arthritis (RA).

MATERIALS AND METHODS

Seventy patients were included in this case-control study. Twenty patients with RA were undergoing B-cell depletion treatment. The second group of RA patients (n = 20) were undergoing non-B-cell depletion treatment with Disease-Modifying Anti-Rheumatic Drugs (DMARD). Control group, with no RA, consisted of 30 individuals. Periodontal parameters including probing depth (PD), clinical attachment level (CAL), bleeding on probing (BOP), gingival index (GI), and plaque index (PI) were recorded. IL-1β and MMP-8 levels in GCF were determined using enzyme-linked immunosorbent assay. Rheumatological parameters including Disease Activity Score-28 (DAS-28), rheumatoid factor levels (RF), and anti-cyclic citrullinated peptide levels were included in the data analyses.

RESULTS

All groups were similar in PD, CAL, BOP, GI, and PI measures. GCF IL-1β levels were 1.85 ± 1.67 pg in the B-cell depletion group, 10.50 ± 13.16 pg in the DMARD group, and 34.12 ± 29.45 pg in the control group (p < 0.001). MMP-8 levels were 21.00 ± 4.23 pg in the B-cell depletion group, 8.16 ± 6.94 pg in the DMARD group, and 21.45 ± 8.67 pg in the control group (p < 0.001). DAS 28, RF, and anti-CCP were similar in RA groups.

CONCLUSIONS

GCF IL-1β levels were significantly lower in B cell depletion group, and MMP-8 levels were significantly lower in DMARD group, suggesting that rheumatoid arthritis treatments may modify biochemical parameters of GCF.

CLINICAL RELEVANCE

This study suggests that host modulation therapies in RA can reduce local production of IL-1β and MMP-8. Reduction of these inflammatory cytokines and enzymes may have a beneficial effect in controlling periodontal tissue destruction.

Relation between anti-Porphyromonas gingivalis antibody titers and HLA-DRB1 neutral alleles in individuals with rheumatoid arthritis

OBJECTIVE

This study aimed to determine the relation between titres of anti-Porphyromonas gingivalis (P. gingivalis) antibody and rheumatoid arthritis (RA) HLA-DRB1 susceptibility region associated with shared epitope (SE) using the Gregersen's and de Vries's classification methods.

MATERIAL AND METHODS

In this cross-sectional study, results of immunoglobulin G1 (IgG1) and immunoglobulin G2 (IgG2) anti-P. gingivalis antibodies, anti-citrullinated protein antibodies (ACPA), diagnosis for RA, and periodontal disease (PD), and a genetic study of the HLA DRB1 region were obtained from 50 patients with RA and 50 control individuals.

RESULTS

Anti-P. gingivalis antibody levels and PD parameters were similar in control and RA groups. Anti-P. gingivalis antibodies were not associated with SE or ACPA. There was no association between ACPA and SE. However, de Vries' classification in RA patients revealed an association between the HLA DRB1 neutral alleles and higher titres of anti-P. gingivalis antibodies as follows: IgG1 anti-P. gingivalis ≥ 1:400 (p = .039); IgG2 anti-P. gingivalis ≥ 1:400 with neutral/neutral genotype (N/N), being exclusive for RA (p = .008); and IgG2 anti-P. gingivalis ≥ 1:200 and N/N (p = .016).

CONCLUSIONS

Although no association was found between SE and anti-P. gingivalis antibodies; according to the de Vries' classification, there was an existing association between HLA DRB1 neutral alleles, with high titres of IgG anti-P.gingivalis antibodies for RA, focussing on novel associations between P.gingivalis and RA.

Another Look at the Contribution of Oral Microbiota to the Pathogenesis of Rheumatoid Arthritis: A Narrative Review

Although autoimmunity contributes to rheumatoid arthritis (RA), several lines of evidence challenge the dogma that it is mainly an autoimmune disorder. As RA-associated human leukocyte antigens shape microbiomes and increase the risk of dysbiosis in mucosae, RA might rather be induced by epigenetic changes in long-lived synovial presenting cells, stressed by excessive translocations into joints of bacteria from the poorly cultivable gut, lung, or oral microbiota (in the same way as more pathogenic bacteria can lead to "reactive arthritis"). This narrative review (i) lists evidence supporting this scenario, including the identification of DNA from oral and gut microbiota in the RA synovium (but in also healthy synovia), and the possibility of translocation through blood, from mucosae to joints, of microbiota, either directly from the oral cavity or from the gut, following an increase of gut permeability worsened by migration within the gut of oral bacteria such as Porphyromonas gingivalis; (ii) suggests other methodologies for future works other than cross-sectional studies of periodontal microbiota in cohorts of patients with RA versus controls, namely, longitudinal studies of oral, gut, blood, and synovial microbiota combined with transcriptomic analyses of immune cells in individual patients at risk of RA, and in overt RA, before, during, and following flares of RA.

Influence of anti-rheumatic agents on the periodontal condition of patients with rheumatoid arthritis and periodontitis: A systematic review and meta-analysis

OBJECTIVE

To evaluate the influence of diverse anti-rheumatic agents on the periodontal condition and to provide clinical medication guidance for patients with rheumatoid arthritis (RA) and periodontitis.

BACKGROUND

In recent years, the correlation between RA and periodontitis has become a hot research topic, but no medication recommendations for patients with RA and periodontitis are available at present.

METHODS

The protocol of this review was registered in advance with PROSPERO (CRD42021248827). Electronic search and manual searches up to March 20, 2021 were conducted. The inclusion criteria for the studies were as follows: included patients diagnosed with periodontitis and RA submitted to anti-rheumatic agent therapy; with a control group receiving no anti-rheumatic agent therapy; with outcomes including at least one periodontal parameter. Probing depth (PD) and clinical attachment loss (CAL) were pooled using weighted mean difference (WMD) and 95% confidence intervals (CI) while gingival index (GI)/modified gingival index (MGI) was analyzed by standardized mean difference (SMD) and 95% CI.

RESULTS

One thousand four hundred and seventy-eight studies potentially related to the aim of this review were screened, but only 463 patients from 14 studies were included in the qualitative analysis, and 146 patients from 4 studies were included in the meta-analysis. Statistically significant reductions were observed among the subjects who received anti-rheumatic agents for PD [WMD = -0.20; 95% CI (-0.33, -0.07); effect p = .003; I²  = 50%; p = .11], CAL [WMD = -0.4; 95% CI (-0.66, -0.15); effect p = .002; I²  = 57%; p = .07] and GI/MGI [SMD = -0.61;95% CI (-0.94, -0.27; effect p = .0004; I²  = 26%; p = .25]. Consistent with the above results, this systematic review produced promising results that PD, CAL, GI/MGI, and bleeding on probing (BOP) decreased when patients with RA and periodontitis were treated with conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs), anti-B lymphocyte agents, anti-IL-6R agents, or JAK inhibitors. PD and CAL declined after the administration of anti-TNF-α agents; most studies reported decreased GI/MGI and BOP, while 2 studies reported increased GI/MGI and BOP.

CONCLUSIONS

These results revealed that csDMARDs, anti-B lymphocyte agents, anti-IL-6R agents, anti-TNF-α agents, and JAK inhibitors had potential positive effects in improving the periodontal condition of patients with RA and periodontitis. However, future research is needed to elucidate whether anti-TNF-α agents have a side effect of increased gingival inflammation.

Porphyromonas gingivalis outside the oral cavity

Porphyromonas gingivalis, a Gram-negative anaerobic bacillus present in periodontal disease, is considered one of the major pathogens in periodontitis. A literature search for English original studies, case series and review articles published up to December 2019 was performed using the MEDLINE, PubMed and GoogleScholar databases, with the search terms "Porphyromonas gingivalis" AND the potentially associated condition or systemic disease Abstracts and full text articles were used to make a review of published research literature on P. gingivalis outside the oral cavity. The main points of interest of this narrative review were: (i) a potential direct action of the bacterium and not the systemic effects of the inflammatory acute-phase response induced by the periodontitis, (ii) the presence of the bacterium (viable or not) in the organ, or (iii) the presence of its virulence factors. Virulence factors (gingipains, capsule, fimbriae, hemagglutinins, lipopolysaccharide, hemolysin, iron uptake transporters, toxic outer membrane blebs/vesicles, and DNA) associated with P. gingivalis can deregulate certain functions in humans, particularly host immune systems, and cause various local and systemic pathologies. The most recent studies linking P. gingivalis to systemic diseases were discussed, remembering particularly the molecular mechanisms involved in different infections, including cerebral, cardiovascular, pulmonary, bone, digestive and peri-natal infections. Recent involvement of P. gingivalis in neurological diseases has been demonstrated. P. gingivalis modulates cellular homeostasis and increases markers of inflammation. It is also a factor in the oxidative stress involved in beta-amyloid production.

Rethink About the Role of Rheumatoid Factor and Anti-citrullinated Protein Antibody in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease characterized by joint inflammation and extra-articular manifestations. Many questions in the pathogenesis, clinical manifestation, and disease spectrum are answered after the discovery of the first autoantibody namely rheumatoid factor (RF). The finding of the second autoantibody named anti-citrullinated protein antibody (ACPA), which unearths the importance of protein citrullination process. It further provides the insight how immune cells and complement interact to perpetuate the inflammatory response. These two autoantibodies pave the way for our better understanding of RA. This review article focuses on the history, pathophysiology, and clinical association of these two autoantibodies in RA.

The onco-immunological implications of Fusobacterium nucleatum in breast cancer

Breast cancer is a leading cause of death worldwide and a better understanding of this disease is needed to improve treatment outcomes. Recent evidence indicates that bacterial dysbiosis is associated with breast cancer, but the bacteria involved remain poorly characterised. Furthermore, an association between periodontal disease, characterised by oral dysbiosis, and breast cancer have also been discovered, but the mechanisms responsible for this association remains to be elucidated. The oral bacterium involved in periodontal disease, Fusobacterium nucleatum, have recently been detected in human breast tumour tissue and it promoted tumour growth and metastatic progression in a mouse model. The mechanisms of how F. nucleatum might colonise breast tissue and how it might promote tumour progression has not been fully elucidated yet. Here we discuss the breast tumour microbiota, its colonisation by F. nucleatum, possible mechanisms by which F. nucleatum might promote breast cancer progression and how this might impact breast cancer treatment. Literature indicates that F. nucleatum might promote breast cancer progression through activating the Toll-like receptor 4 pathway and by supressing the immune system. This results in cell growth and treatment resistance through autophagy as well as immune evasion. Targeted treatment directed at F. nucleatum combined with immunotherapy and autophagy inhibitors might therefore be a feasible treatment strategy for breast cancer patients.

Developing a Tooth in situ Organ Culture Model for Dental and Periodontal Regeneration Research

In this study we have realized the need for an organ culture tooth in situ model to simulate the tooth structure especially the tooth attachment apparatus. The importance of such a model is to open avenues for investigating regeneration of the complex tooth and tooth attachment tissues and to reduce the need for experimental animals in investigating dental materials and treatments in the future. The aim of this study was to develop a porcine tooth in situ organ culture model and a novel bioreactor suitable for future studies of periodontal regeneration, including application of appropriate physiological loading. The Objectives of this study was to establish tissue viability, maintenance of tissue structure, and model sterility after 1 and 4 days of culture. To model diffusion characteristics within the organ culture system and design and develop a bioreactor that allows tooth loading and simulation of the chewing cycle. Methods: Twenty-one porcine first molars were dissected aseptically in situ within their bony sockets. Twelve were used to optimize sterility and determine tissue viability. The remainder were used in a 4-day organ culture study in basal medium. Sterility was determined for medium samples and swabs taken from all tissue components, using standard aerobic and anaerobic microbiological cultures. Tissue viability was determined at days 1 and 4 using an XTT assay and Glucose consumption assays. Maintenance of structure was confirmed using histology and histomorphometric analysis. Diffusion characteristics were investigated using micro-CT combined with finite element modeling. A suitable bioreactor was designed to permit longer term culture with application of mechanical loading to the tooth in situ. Result: XTT and Glucose consumption assays confirmed viability throughout the culture period for all tissues investigated. Histological and histomorphometric analysis confirmed maintenance of tissue structure. Clear microbiological cultures indicated maintenance of sterility within the organ culture system. The novel bioreactor showed no evidence of medium contamination after 4 days of culture. Finite element modeling indicated nutrient availability to the periodontium. Conclusion: A whole tooth in situ organ culture system was successfully maintained over 4 days in vitro.

Oral Dysbiosis and Autoimmunity: From Local Periodontal Responses to an Imbalanced Systemic Immunity. A Review

The current paradigm of onset and progression of periodontitis includes oral dysbiosis directed by inflammophilic bacteria, leading to altered resolution of inflammation and lack of regulation of the inflammatory responses. In the construction of explanatory models of the etiopathogenesis of periodontal disease, autoimmune mechanisms were among the first to be explored and historically, for more than five decades, they have been described in an isolated manner as part of the tissue damage process observed in periodontitis, however direct participation of these mechanisms in the tissue damage is still controversial. Autoimmunity is affected by genetic and environmental factors, leading to an imbalance between the effector and regulatory responses, mostly associated with failed resolution mechanisms. However, dysbiosis/infection and chronic inflammation could trigger autoimmunity by several mechanisms including bystander activation, dysregulation of toll-like receptors, amplification of autoimmunity by cytokines, epitope spreading, autoantigens complementarity, autoantigens overproduction, microbial translocation, molecular mimicry, superantigens, and activation or inhibition of receptors related to autoimmunity by microorganisms. Even though autoreactivity in periodontitis is biologically plausible, the associated mechanisms could be related to non-pathologic responses which could even explain non-recognized physiological functions. In this review we shall discuss from a descriptive point of view, the autoimmune mechanisms related to periodontitis physio-pathogenesis and the participation of oral dysbiosis on local periodontal autoimmune responses as well as on different systemic inflammatory diseases.

Polymyxin B prevents the development of adjuvant arthritis via modulation of TLR/Cox-2 signaling pathway

AIMS

Several microbial toll-like receptor (TLR) ligands, bacterial DNA and bacterial cell wall fragments have been identified in the synovium of rheumatoid arthritis (RA) patients, proving bacterial involvement in the pathogenesis of RA. The current study aimed to verify that low dose polymyxin B could prevent the development of chronic inflammatory arthritis.

METHODS

Twelve days post adjuvant injection, Sprague-Dawley rats were treated twice weekly with methotrexate (0.5 mg/kg) or daily with polymyxin B (1 mg/kg) or with combination of both for 1 or 2 weeks. Arthritis progression was assessed by hind paw swelling, serum levels of tumor growth factor-1β (TGF-1β), tumor necrosis factor-alpha (TNF-α), high sensitivity C-reactive protein (HS-CRP) and nuclear factor kappa B (NF-κB) were measured using ELISA. Cyclooxygenase-1 (Cox-1) and Cox-2 activities, as well as mRNA expression of TLR-2 and TLR-4 were determined. Histopathological examination of the ankle joint was performed as well as immunohistochemistry for anti-TLR-4. Histopathological assessment of toxic effects on the kidney was performed.

KEY FINDINGS

Adjuvant arthritis led to a significant swelling of the hind paw and alteration in all serum parameters, TLR-2 and TLR-4 expression, as well as Cox-2 activity. These alterations were associated with histopathological changes of the joints. Polymyxin B reduced significantly all biomarkers of inflammation, showing better effect of the combination in most of the studied parameters, with minimal signs of nephrotoxicity.

SIGNIFICANCE

In conclusion, results showed that polymyxin B possesses significant anti-arthritic activity which may be attributed to inhibition of the TLR-4, NF-κB and Cox-2 signaling pathway.

Gout can increase the risk of periodontal disease in Taiwan

Objectives: To evaluate the risk of periodontal disease (PD) in gout patients. Methods: This retrospective cohort study was conducted using data from the Longitudinal Health Insurance Database 2000. The gout cohort included 31,759 patients newly diagnosed with gout from 2000 to 2012, and the comparison (nongout) cohort included 63,517 patients. Univariate and multivariable adjusted hazard ratios (aHRs), with corresponding 95% confidence intervals (CIs), were estimated using the Cox proportional hazard model for determining the occurrence of PD in both cohorts. We also measured the cumulative incidence of PD in these two cohorts using the Kaplan-Meier method and assessed the curve difference using the log-rank test. Results: The mean follow-up time was more than 6 years for both cohorts. The overall incidence rate of PD was significantly higher in the gout cohort than in the comparison cohort (5.04 vs 4.16 per 10,000 person-years; aHR = 1.13, 95% CI = 1.10-1.16). Only patients using colchicine had a significantly lower risk of PD (aHR = 0.85, 95% CI = 0.79-0.91). Conclusion: In our study, patients with gout showed an increased risk of PD, and treatment with colchicine could decrease the risk. Abbreviations: PD: periodontal disease; LHID: Longitudinal Health Insurance Research Database; NHIRD, National Health Insurance Research Database; ICD-9-CM: International Classification of Diseases, Ninth Revision, Clinical Modification; CI: confidence interval; HR: hazard ratio.

An Overview of the Intrinsic Role of Citrullination in Autoimmune Disorders

A protein undergoes many types of posttranslation modification. Citrullination is one of these modifications, where an arginine amino acid is converted to a citrulline amino acid. This process depends on catalytic enzymes such as peptidylarginine deiminase enzymes (PADs). This modification leads to a charge shift, which affects the protein structure, protein-protein interactions, and hydrogen bond formation, and it may cause protein denaturation. The irreversible citrullination reaction is not limited to a specific protein, cell, or tissue. It can target a wide range of proteins in the cell membrane, cytoplasm, nucleus, and mitochondria. Citrullination is a normal reaction during cell death. Apoptosis is normally accompanied with a clearance process via scavenger cells. A defect in the clearance system either in terms of efficiency or capacity may occur due to massive cell death, which may result in the accumulation and leakage of PAD enzymes and the citrullinated peptide from the necrotized cell which could be recognized by the immune system, where the immunological tolerance will be avoided and the autoimmune disorders will be subsequently triggered. The induction of autoimmune responses, autoantibody production, and cytokines involved in the major autoimmune diseases will be discussed.

Microbiota in Human Periodontal Abscess Revealed by 16S rDNA Sequencing

Periodontal abscess is an oral infective disease caused by various kinds of bacteria. We aimed to characterize the microbiota composition of periodontal abscesses by metagenomic methods and compare it to that of the corresponding pocket and healthy gingival crevice to investigate the specific bacteria associated with this disease. Samples from abscess pus (AB), periodontal pocket coronally above the abscess (PO), and the gingival crevice of the periodontal healthy tooth were obtained from 20 periodontal abscess patients. Furthermore, healthy gingival crevice samples were obtained from 25 healthy individuals. Bacterial DNA was extracted and 16S rRNA gene fragments were sequenced to characterize the microbiota and determine taxonomic classification. The beta-diversity analysis results showed that the AB and PO groups had similar compositions. Porphyromonas gingivalis, Prevotella intermedia, and other Prevotella spp. were the predominant bacteria of human periodontal abscesses. The abundances of Filifactor alocis and Atopobium rimae were significantly higher in periodontal abscesses than in the periodontal pocket, suggesting their association with periodontal abscess formation. In conclusion, we characterized the microbiota in periodontal abscess and identified some species that are positively associated with this disease. This provides a better understanding of the components of periodontal abscesses, which will help facilitate the development of antibiotic therapy strategies.

Oral health assessment of independent elders in Texas

BACKGROUND

The oral health status of older adults in North Texas is largely unknown.

METHODS

This cross-sectional, pilot study used the Basic Screening Survey for older adults involving a self-administered questionnaire and oral screening examination of 155 adults aged 65 years and older, in four Dallas, TX settings, stratified socioeconomically. Recruitment occurred from July 2012 through March 2014.

RESULTS

Participants were between 65 and 90 years of age. The sample was predominantly female (64%), reflecting Texas population diversity with 49.7% White, 34.2% Hispanic, 14.2% Black, and 1.8% others. Missing teeth number (P < .019), functional contacts, untreated decay, root decay (P < .05), tooth mobility, root fragments and need for emergency treatment (P < .021) differed significantly regarding site and ethnicity. Participants at the least affluent sites (two) evidenced significant unmet dental needs and suboptimal access to care. In contrast, those at the most affluent sites (also oldest participants) had good oral health and access to care.

CONCLUSIONS

There are profound oral health disparities in urban North Texas based on socioeconomic status. These findings suggest that poor oral health is not inevitable in the elderly, as long as there is access to care. Larger-scale studies are required to broadly address oral health disparities among elderly Texans.

Comparative evaluation of Gingival Crevicular Fluid (GCF) levels of Interleukin-34 levels in periodontally healthy and in patients with chronic and aggressive periodontitis- A cross-sectional study

Background and objectives

Proinflammatory cytokines appear to have a central role in the destruction of periodontal tissues. By binding to Receptor Activator of Nuclear Factor κb (RANK) on osteoclast progenitor cells, these cytokines are locally responsible for the activation of bone resorbing osteoclasts differentiation and function. Interleukin-34 (IL-34) is a proinflammatory cytokine derived from the osteoblasts and plays an important role in osteoclastogenesis. The present study was carried out to assess the levels of IL-34 in Gingival Crevicular Fluid (GCF) in periodontally healthy patients, chronic periodontitis and aggressive periodontitis.

Materials and method

A total of 90 patients were recruited in the study and were divided into 3 groups: Periodontally healthy patients (Group I), Chronic periodontitis (Group II) and Aggressive periodontitis (Group III). Clinical Parameters like plaque index, gingival index, probing depth, clinical attachment levels were recorded and GCF samples were collected at baseline for the assessment of IL-34 levels in all the three groups. IL-34 levels were calculated using Enzyme-Linked Immune-Sorbent Assay (ELISA).

Results

The mean GCF levels of IL-34 in Group I was 47.22 ± 18.04 pg/ml, Group II was 103.76 ± 26.61 pg/ml and in Group III was 191.71 ± 49.24 pg/ml. The mean GCF IL-34 level was found to be higher in Group III followed by Group II and Group I. The IL-34 levels correlated with clinical parameters like plaque index, gingival index, probing depth, clinical attachment levels. But correlation with probing depth and clinical attachment level were significantly higher in Group III followed by Group II and Group I.

Interpretation and conclusion

The study demonstrated higher levels of IL-34 in aggressive periodontitis when compared with chronic periodontitis. IL-34, a novel diagnostic marker which was found to be at higher level in GCF of aggressive and chronic periodontitis patients.

Dysbiosis of Skin Microbiota in Psoriatic Patients: Co-occurrence of Fungal and Bacterial Communities

Psoriasis is a chronic inflammatory skin disease, whose pathogenesis involves dysregulated interplay among immune cells, keratinocytes and environmental triggers, including microbiota. Bacterial and fungal dysbiosis has been recently associated with several chronic immune-mediated diseases including psoriasis. In this comprehensive study, we investigated how different sampling sites and methods reflect the uncovered skin microbiota composition. After establishing the most suitable approach, we further examined correlations between bacteria and fungi on the psoriatic skin. We compared microbiota composition determined in the same sample by sequencing two distinct hypervariable regions of the 16S rRNA gene. We showed that using the V3V4 region led to higher species richness and evenness than using the V1V2 region. In particular, genera, such as Staphylococcus and Micrococcus were more abundant when using the V3V4 region, while Planococcaceae, on the other hand, were detected only by the V1V2 region. We performed a detailed analysis of skin microbiota composition of psoriatic lesions, unaffected psoriatic skin, and healthy control skin from the back and elbow. Only a few discriminative features were uncovered, mostly specific for the sampling site or method (swab, scraping, or biopsy). Swabs from psoriatic lesions on the back and the elbow were associated with increased abundance of Brevibacterium and Kocuria palustris and Gordonia, respectively. In the same samples from psoriatic lesions, we found a significantly higher abundance of the fungus Malassezia restricta on the back, while Malassezia sympodialis dominated the elbow mycobiota. In psoriatic elbow skin, we found significant correlation between occurrence of Kocuria, Lactobacillus, and Streptococcus with Saccharomyces, which was not observed in healthy skin. For the first time, we showed here a psoriasis-specific correlation between fungal and bacterial species, suggesting a link between competition for niche occupancy and psoriasis. However, it still remains to be elucidated whether observed microbial shift and specific inter-kingdom relationship pattern are of primary etiological significance or secondary to the disease.

Association between intensive periodontal treatment and spontaneous intracerebral hemorrhage-a nationwide, population-based cohort study

Periodontal disease is a chronic inflammation of periodontium and has a high prevalence. Periodontal disease has been discovered to be a possible risk factor for cerebrovascular diseases. The available evidence are not enough to set up a causal relationship between periodontal disease and cerebrovascular diseases. Patients with spontaneous intracerebral hemorrhage have high mortality rates. The present study investigated whether intensive periodontal treatment is a protective factor of spontaneous intracerebral hemorrhage and can reduce the risk of spontaneous intracerebral hemorrhage.In total, 64,960 patients with a history of periodontal disease were picked out from the National Health Insurance Research Databases as a case-cohort from January 01, 2000 to December 31, 2010. They were divided on the basis of whether periodontal disease patients received intensive surgical treatment (treatment cohort) or not (control cohort). The periodontal disease patients in treatment and control cohorts were selected by propensity score matching at a ratio of 1:1. Incidences of spontaneous intracerebral hemorrhage in both cohorts were analyzed and compared.The total hazard of spontaneous intracerebral hemorrhage was significantly decreased in the treatment cohorts compared with the control cohorts (adjusted hazard ratio = 0.60, 95% confidence interval = 0.45-0.79).Compared with the control cohort, intensive periodontal treatment may reduce the overall incidence of spontaneous intracerebral hemorrhage, particularly in elderly patients, males, and those who received more than 2 intensive treatments.

A Secreted Bacterial Peptidylarginine Deiminase Can Neutralize Human Innate Immune Defenses

The keystone oral pathogen Porphyromonas gingivalis is associated with severe periodontitis. Intriguingly, this bacterium is known to secrete large amounts of an enzyme that converts peptidylarginine into citrulline residues. The present study was aimed at identifying possible functions of this citrullinating enzyme, named Porphyromonas peptidylarginine deiminase (PPAD), in the periodontal environment. The results show that PPAD is detectable in the gingiva of patients with periodontitis, and that it literally neutralizes human innate immune defenses at three distinct levels, namely bacterial phagocytosis, capture in neutrophil extracellular traps (NETs), and killing by the lysozyme-derived cationic antimicrobial peptide LP9. As shown by mass spectrometry, exposure of neutrophils to PPAD-proficient bacteria reduces the levels of neutrophil proteins involved in phagocytosis and the bactericidal histone H2. Further, PPAD is shown to citrullinate the histone H3, thereby facilitating the bacterial escape from NETs. Last, PPAD is shown to citrullinate LP9, thereby restricting its antimicrobial activity. The importance of PPAD for immune evasion is corroborated in the infection model Galleria mellonella, which only possesses an innate immune system. Together, the present observations show that PPAD-catalyzed protein citrullination defuses innate immune responses in the oral cavity, and that the citrullinating enzyme of P. gingivalis represents a new type of bacterial immune evasion factor.IMPORTANCE Bacterial pathogens do not only succeed in breaking the barriers that protect humans from infection, but they also manage to evade insults from the human immune system. The importance of the present study resides in the fact that protein citrullination is shown to represent a new bacterial mechanism for immune evasion. In particular, the oral pathogen P. gingivalis employs this mechanism to defuse innate immune responses by secreting a protein-citrullinating enzyme. Of note, this finding impacts not only the global health problem of periodontitis, but it also extends to the prevalent autoimmune disease rheumatoid arthritis, which has been strongly associated with periodontitis, PPAD activity, and loss of tolerance against citrullinated proteins, such as the histone H3.

Anti-rheumatic medication and salivary MMP-8, a biomarker for periodontal disease

OBJECTIVE

To investigate the impact of anti-rheumatic medications on salivary matrix metalloproteinase (MMP)-8 levels and MMP-8/TIMP (tissue inhibitor of MMPs)-1 ratio in patients with rheumatoid arthritis (RA) and periodontal findings during a 1-year follow-up.

MATERIALS AND METHODS

Salivary MMP-8 was measured by an immunofluorometric assay and TIMP-1 by an enzyme-linked immunosorbent assay of 53 patients with early untreated RA (ERA), naïve to synthetic disease modifying anti-rheumatic drugs (DMARDs), of 28 patients with chronic RA (CRA), candidates for biologic DMARDs and of 43 age- and sex-matched controls. Periodontal health was evaluated by bleeding on probing (BOP), pocket depth (PD), and periodontal inflammatory burden index (PIBI). Examinations were conducted twice for RA patients and once for controls.

RESULTS

Salivary MMP-8 level and MMP-8/TIMP-1 ratio associated positively with PIBI in patients with chronic RA (MMP-8: p < 0.001 at baseline, p = 0.002 after follow-up; MMP-8/TIMP-1 ratio p < 0.001, p = 0.003, respectively) and in controls (MMP-8: p = 0.010, MMP-8/TIMP-1 ratio: p = 0.010). Salivary MMP-8 levels were highest at the early stage of RA. The used DMARDs, synthetic or biologic, did not affect salivary MMP-8 concentrations.

CONCLUSIONS

The use of synthetic or biologic DMARDs did not affect salivary MMP-8 levels in RA patients regardless the duration of RA.

It Takes "Guts" to Cause Joint Inflammation: Role of Innate-Like T Cells

Innate-like T cells such as invariant natural killer T (iNKT) cells and mucosal-associated T (MAIT) cells, characterized by a semi-invariant T cell receptor and restriction toward MHC-like molecules (CD1 and MR1 respectively), are a unique unconventional immune subset acting at the interface of innate and adaptive immunity. Highly represented at barrier sites and capable of rapidly producing substantial amounts of cytokines, they serve a pivotal role as first-line responders against microbial infections. In contrast, it was demonstrated that innate-like T cells can be skewed toward a predominant pro-inflammatory state and are consequently involved in a number of autoimmune and inflammatory diseases like inflammatory bowel diseases and rheumatic disorders, such as spondyloarthritis (SpA) and rheumatoid arthritis. Interestingly, there is link between gut and joint disease as they often co-incide and share certain aspects of the pathogenesis such as established genetic risk factors, a critical role for pro-inflammatory cytokines, such as TNF-α, IL-23, and IL-17 and therapeutic susceptibility. In this regard dysregulated IL-23/IL-17 responses appear to be crucial in both debilitating pathologies and innate-like T cells likely act as key player. In this review, we will explore the remarkable features of iNKT cells and MAIT cells, and discuss their contribution to immunity and combined gut-joint disease.

Inflammatory biomarkers in saliva and serum of patients with rheumatoid arthritis with respect to periodontal status

OBJECTIVE

To study prospectively the association of salivary and serum matrix metalloproteinase (MMP)-8, tissue inhibitor of MMPs (TIMP)-1 and interleukin (IL)-6 with periodontal and systemic inflammation in rheumatoid arthritis (RA). We hypothesized that biomarker concentrations reflect inflammation.

METHODS

Fifty three early untreated RA (ERA) and 28 chronic RA (CRA) patients, underwent rheumatological and dental examinations at baseline and one year later after starting first conventional or biological disease modifying antirheumatic drug. We included 43 control subjects. Saliva and serum samples were analyzed for MMP-8, TIMP-1 and IL-6. Periodontal health was assessed by bleeding on probing (BOP), pocket depth (PD) and periodontal inflammatory burden index (PIBI); RA disease activity was assessed by disease activity score DAS28. Joint destruction was analyzed by the modified Sharp-van der Heijde (SHS) method.

RESULTS

Serum MMP-8 (p < .001; p < .001) and IL-6 (p < .001; p = .002) were significantly higher in CRA vs. other study groups during the study. Salivary MMP-8 (p = .010) and IL-6 (p = .010) were significantly higher in ERA vs. other study groups at baseline. Salivary MMP-8 was associated with periodontal parameters.

CONCLUSION

Elevated serum concentrations of MMP-8 and IL-6 in CRA patients reflected chronic RA, while elevated salivary concentrations of MMP-8 levels in ERA patients reflected increased periodontal inflammation. Key messages Concentrations of inflammatory biomarkers in serum and saliva were different between patients with RA and healthy controls. Concentrations of MMP-8 and of IL-6 in serum were elevated in patients with chronic RA reflecting joint inflammation and the burden of established RA. Concentrations of MMP-8 in saliva was elevated already at the early stage of RA and the level of salivary MMP-8 was associated with poor periodontal health both in patients with early and in those with chronic RA.

B cell subset distribution is altered in patients with severe periodontitis

Several studies have recently highlighted the implication of B cells in physiopathogenesis of periodontal disease by showing that a B cell deficiency leads to improved periodontal parameters. However, the detailed profiles of circulating B cell subsets have not yet been investigated in patients with severe periodontitis (SP). We hypothesised that an abnormal distribution of B cell subsets could be detected in the blood of patients with severe periodontal lesions, as already reported for patients with chronic inflammatory diseases as systemic autoimmune diseases. Fifteen subjects with SP and 13 subjects without periodontitis, according to the definition proposed by the CDC periodontal disease surveillance work group, were enrolled in this pilot observational study. Two flow cytometry panels were designed to analyse the circulating B and B1 cell subset distribution in association with the RANKL expression. A significantly higher percentage of CD27⁺ memory B cells was observed in patients with SP. Among these CD27⁺ B cells, the proportion of the switched memory subset was significantly higher. At the same time, human B1 cells, which were previously associated with a regulatory function (CD20⁺CD69^-CD43⁺CD27⁺CD11b⁺), decreased in SP patients. The RANKL expression increased in every B cell subset from the SP patients and was significantly greater in activated B cells than in the subjects without periodontitis. These preliminary results demonstrate the altered distribution of B cells in the context of severe periodontitis. Further investigations with a larger cohort of patients can elucidate if the analysis of the B cell compartment distribution can reflect the periodontal disease activity and be a reliable marker for its prognosis (clinical trial registration number: NCT02833285, B cell functions in periodontitis).

Autoimmune Diseases and Oral Health: 30-Year Follow-Up of a Swedish Cohort

Oral infections up-regulate a number of systemic inflammatory reactions that, in turn, play a role in the development of systemic diseases. We investigated the association between oral health and autoimmune diseases in a cohort of Swedish adults. Hypothesis was that poor oral health associates with incidence of autoimmune diseases. Overall 1676 subjects aged 30–40 years old from Stockholm County (Sweden) participated in this study in 1985. Subjects were randomly selected from the registry file of Stockholm region and were followed-up for 30 years. Their hospital and open health care admissions (World Health Organization ICD 9 and 10 codes) were recorded from the Swedish national health registers. The association between the diagnosed autoimmune disease and the oral health variables were statistically analyzed. In all, 50 patients with autoimmune diagnoses were detected from the data. Plaque index was significantly higher in the autoimmune disease group (≥median 35 (70%) vs. ˂median 872 (54%), p = 0.030). No statistical difference was found in gingival index, calculus index, missing teeth, periodontal pockets, smoking or snuff use between patients with and without autoimmune disease. Our study hypothesis was partly confirmed. The result showed that subjects with a higher plaque index, marker of poor oral hygiene, were more likely to develop autoimmune diseases in 30 years.

Factors associated with the risk of gingival disease in patients with rheumatoid arthritis

Gingival disase and rheumatoid arthritis (RA) are linked at both the epidemiologic and pathogenesis levels. In this study, we aimed to identify environmental factors associated with RA and gingival disease and to investigate factors that protect the gingival tissue in RA patients. This retrospective study analyzed 754 RA patients with gingival disease selected from the NHANES database who completed the mobile examination center interview/examination between 1999 and 2004. Data collected included demographics, lifestyle, dietary intake, and biomarkers. The study included 173 RA patients with gingival disease. Multivariate logistic regression analysis showed that the odds of gingival disease were significantly increased with male gender. However, the odds of gingival disease was significantly decreased with increased vitamin C intake (OR = 0.996, p = 0.041), and higher serum vitamin D levels (OR = 0.979, p = 0.011). Given the significant association between the prevalence of gingival disease and RA, identification of risk factors of gingival disease will be useful as a screening tool in national health surveys to improve the management of periodontal disease in patients with RA.

Estimation of Pentraxin 3 and Porphyromonas Gingivalis Levels in Patients with Rheumatoid Arthritis and Periodontitis- An Observational Study

INTRODUCTION

Periodontal diseases are inflammatory in nature involving interplay between the bacterial plaque and the micro-organisms, with the response of the host playing a pivotal role in either attenuating or eliminating the disease. Rheumatoid Arthritis (RA) is also a chronic inflammatory disease which shares common risk factors with periodontitis. Porphyromonas Gingivalis and Pentraxin 3 (an acute inflammatory protein) have been observed to be associated with both the diseases.

AIM

This study was done to determine if there was any association between Pophyromonas Gingivalis and Pentraxin 3 levels in patients with RA and Chronic Periodontitis in comparison with Healthy controls.

MATERIALS AND METHODS

This observational study was conducted on 90 subjects (42 Males and 48 Females) aged between 30-60 years. The subjects were selected from the out patient ward of a tertiary referral care hospital. The selected subjects were equally divided into three groups. Group I: Comprising of 30 patients with RA and chronic periodontitis who were in turn, subdivided into Group I- A (n=15) -Patients just diagnosed with RA and Group I- B (n=15) Patients under medications for more than three months. Group II: Patients with Chronic Periodontitis (n=30) and Group III: Healthy Controls (n=30) Intergroup comparison for continuous data was done by One-way analysis of variance test followed by Bonferroni's post-hoc test. Intragroup comparison for continuous data was done by paired t-test.

RESULTS

Intergroup comparison between Group I and Group II did not show any statistical difference pertaining to the clinical parameters except for the Gingival Index (GI) which was found to be higher in Group II (Mean= 2.07) when compared to Group I (Mean=1.59). Intragroup comparison between Group IA and Group IB was statistically significant for GI, Plaque Index (PI), and Clinical Attachment Levels (CAL). Intragroup comparison between Group I-A and Group I-B showed that both Porphyromonas gingivalis and Pentraxin 3 Levels were higher in Group I- A.

CONCLUSION

In this study, it was observed that there was a positive association between Porphyromonas gingivalis and Pentraxin 3 levels in patients with rheumatoid arthritis and periodontitis.

Effects of avocado/soybean unsaponifiables (ASU) on the treatment of ligature-induced periodontitis in rats

The purpose of this study is to evaluate the effect of the avocado/soybean unsaponifiables (ASU) on the treatment of induced periodontitis in rats. Periodontitis was induced in 84 rats via ligature placement around the second upper molar, which was removed after 7 days, and scaling and root planning (SRP) was performed at this time. Subsequently, the rats were randomly allocated to four groups with 21 animals each: One SRP group in which saline solution was administered (SS), and three groups in which ASU was administered (0.6 g/kg/day), beginning either 7 days before the induction of periodontitis (SRP/ASU-7), on the day of periodontitis induction (SRP/ASU0), or on the day of treatment (SRP/ASU+7). ASU and SS were administered daily by gavage until the sacrifice of the animals (7, 15, and 30 days after SRP). The % bone in the furcation area was evaluated by histomorphometry and micro-CT. The expression of proteins (TRAP, RANKL, and alkaline phosphatase) and mRNA (IL-1β, TNF-α, IL-6, RANKL, and alkaline phosphatase) were evaluated by immunohistochemistry and qPCR. The SRP/ASU+7 group presented a higher percentage of bone fill in the furcation area and higher expression of alkaline phosphatase than in the SRP group (at 7 and 30 days, respectively). The SRP/ASU0 and SRP/ASU+7 groups presented lower expression levels of RANKL mRNA than the SRP and SRP/ASU-7 groups at 15 days. ASU administration on the day of the SRP treatment of the ligature-induced periodontitis promoted subtle beneficial effects on periodontal repair following the treatment of induced periodontitis within the experimental period of 7 days.

Correlation of Periodontal Disease With Inflammatory Arthritis in the Time Before Modern Medical Intervention

BACKGROUND

Controversy exists regarding possible correlation of periodontal disease with rheumatoid arthritis (RA) and ankylosing spondylitis (AS). Confounding factors may relate to stringency of inflammatory disease diagnosis and the effect of therapeutic intervention for RA on periodontal disease. These factors are investigated in this study.

METHODS

Forty-five individuals with documented RA (n = 15), spondyloarthropathy (n = 15), and calcium pyrophosphate deposition disease (CPPD) (n = 15), from the Hamann-Todd collection of human skeletons compiled from 1912 to 1938, and 15 individuals contemporarily incorporated in the collection were examined for tooth loss, cavity occurrence, average and maximum lingual and buccal depth of space between tooth and bone, periosteal reaction, serpentine bone resorption, abscess formation, and root penetration of the bone surface and analyzed by analysis of variance.

RESULTS

Tooth loss was common, but actual number of teeth lost, cavity occurrence, average and maximum lingual and buccal depth of space between tooth and bone, periosteal reaction, serpentine grooving surrounding teeth (considered a sign of inflammation), abscess formation, and root exposure (penetration of bone surface) were indistinguishable among controls and individuals with RA, spondyloarthropathy, and CPPD.

CONCLUSIONS

Although many factors can affect periodontal disease, presence of inflammatory arthritis does not appear to be one of them. The implication is that dental disease was common in the general population and not necessarily associated with arthritis, at least before the advent of modern rheumatologic medications. As specific diagnosis did not affect prevalence, perhaps current prevalence controversy may relate to current intervention, a subject for further study.

What rheumatologists should know about orofacial manifestations of autoimmune rheumatic diseases

Orofacial manifestations occur frequently in rheumatic diseases and usually represent early signs of disease or of its activity that are still neglected in clinical practice. Among the autoimmune rheumatic diseases with potential for oral manifestations, rheumatoid arthritis (RA), inflammatory myopathies (IM), systemic sclerosis (SSc), systemic lupus erythematosus (SLE), relapsing polychondritis (RP) and Sjögren's syndrome (SS) can be cited. Signs and symptoms such as oral hyposalivation, xerostomia, temporomandibular joint disorders, lesions of the oral mucosa, periodontal disease, dysphagia, and dysphonia may be the first expression of these rheumatic diseases. This article reviews the main orofacial manifestations of rheumatic diseases that may be of interest to the rheumatologist for diagnosis and monitoring of autoimmune rheumatic diseases.

Effect of avocado/soybean unsaponifiables on ligature-induced bone loss and bone repair after ligature removal in rats

BACKGROUND AND OBJECTIVE

The aim of this study was to evaluate the effects of administration of avocado/soybean unsaponifiable (ASU), a drug that is commonly used in the treatment of rheumatoid arthritis, on ligature-induced bone loss and bone repair after ligature removal in rats.

MATERIAL AND METHODS

Eighty-four rats were randomly assigned to four groups of equal size and received a daily gavage of either sterile saline [control (CTR)] or ASU (0.6 mg/kg), starting 7 d before (ASU/-7), on the day of (ASU/0) or 7 d after (ASU/+7) periodontitis induction. Periodontitis was induced by placing silk ligatures into the gingival sulcus of the second maxillary molars for 7 d; after 7 d, the ligatures were removed. Seven rats from each group were sacrificed, 7, 15 or 30 d after ligature removal. Bone resorption was evaluated by histomorphometry and micro-computed tomography (micro-CT). Immunohistochemistry was used to evaluate the expression of TRAP, RANKL and alkaline phosphatase (ALP), and quantitative PCR (qPCR) was used to evaluate the levels of interleukin-1beta (Il1β), tumor necrosis factor alpha (Tnfα), interleukin-6 (Il-6), Rankl and Alp. Statistical analysis was performed using the Shapiro-Wilk test, ANOVA and Tukey's test for normal data, and using the Kruskall-Wallis and Dunnet's tests for non-normal data (p < 0.05).

RESULTS

Histomorphometry and micro-CT analysis showed greater bone resorption in the CTR group than in the ASU/0 (15 d) and ASU/+7 (7 and 15 d) groups. The CTR group also presented with a higher expression of TRAP (15 and 30 d) and RANKL (7 and 15 d) compared with ASU/0 and ASU/+7 groups. Similarly, qPCR analysis showed higher levels of Rankl and Il1β mRNAs, and lower levels of Alp mRNA, in the CTR group compared with all other groups (for all periods).

CONCLUSION

ASU exhibited a positive effect on bone repair following ligature-induced periodontitis in rats.

What rheumatologists should know about orofacial manifestations of autoimmune rheumatic diseases

Orofacial manifestations occur frequently in rheumatic diseases and usually represent early signs of disease or of its activity that are still neglected in clinical practice. Among the autoimmune rheumatic diseases with potential for oral manifestations, rheumatoid arthritis (RA), inflammatory myopathies (IM), systemic sclerosis (SSc), systemic lupus erythematosus (SLE), relapsing polychondritis (RP) and Sjögren's syndrome (SS) can be cited. Signs and symptoms such as oral hyposalivation, xerostomia, temporomandibular joint disorders, lesions of the oral mucosa, periodontal disease, dysphagia, and dysphonia may be the first expression of these rheumatic diseases. This article reviews the main orofacial manifestations of rheumatic diseases that may be of interest to the rheumatologist for diagnosis and monitoring of autoimmune rheumatic diseases.

Rheumatoid Arthritis Risk Associated with Periodontitis Exposure: A Nationwide, Population-Based Cohort Study

BACKGROUND

The risk of periodontitis (PD) is increased in the patient group of rheumatoid arthritis (RA). RA and PD also shared some pathological mechanism. The aim of this study is to investigate the risk of RA associated with PD exposure.

METHODS AND FINDINGS

This study identified 3 mutually exclusive cohorts using the 1999-2010 Taiwanese National Health Insurance Research Database (NHIRD) to investigate the association between PD and the risk of incident RA. All patients with PD in 2000 were identified from the database of all enrollees as the PD cohort. From the representative database of 1,000,000 enrollees randomly selected in 2010 (LHID2010), individuals without any periodontal disease (PO) during 1999-2010 were selected as the non-PO cohort. Individuals who were not included in the non-PO cohort and received dental scaling (DS) no more than two times per year during 1999-2010 were selected as the DS cohort from LHID2010. Using cox proportional regression analysis, hazard ratios (HRs) with 95% confidence intervals (Cis) were calculated to quantify the association between PD exposure and RA development. In the three-group comparison using the non-PO cohort as reference, we found that the risk of RA was higher in the PD and DS cohorts (HRs, 1.89 and 1.43; 95% CIs, 1.56-2.29 and 1.09-1.87, respectively). For comparisons between two cohorts, the PD cohort had a higher risk of RA than the non-PO and DS cohorts (HRs, 1.91 and 1.35; 95% CIs, 1.57-2.30 and 1.09-1.67, respectively).

CONCLUSION

PD was associated with an increased risk of RA development.

Prophylactic Injection of Recombinant Alpha-Enolase Reduces Arthritis Severity in the Collagen-Induced Arthritis Mice Model

Objective

To evaluate the ability of the glycolytic enzyme alpha-enolase (ENO1) or its immunodominant peptide (pEP1) to reduce the severity of CIA in DBA/1 mice when injected in a prophylactic way.

Methods

Mice were treated with mouse ENO1 or pEP1 one day prior to collagen II immunization. Clinical assessment was evaluated using 4 parameters (global and articular scores, ankle thickness and weight). Titers of serum anti-ENO1, anti-cyclic citrullinated peptides (anti-CCP) and anti-CII (total IgG and IgG1/IgG2a isotypes) antibodies were measured by ELISA at different time-points. Disease activity was assessed by histological analysis of both anterior and hind paws at the end of experimentation.

Results

Prophylactic injection of 100 μg of ENO1 reduced severity of CIA. Serum levels of anti-CII antibodies were reduced in ENO1-treated mice. Concordantly, ENO1-treated mice joints presented less severe histological signs of arthritis. ENO1 did not induce a shift toward a Th2 response since IgG1/IgG2a ratio of anti-CII antibodies remained unchanged and IL-4 serum levels were similar to those measured in the control group.

Conclusions

Pre-immunization with ENO1 or its immunodominant peptide pEP1 reduces CIA severity at the clinical, immunological and histological levels. Effects of pEP1 were less pronounced. This immunomodulatory effect is associated with a reduction in anti-CII antibodies production but is not due to a Th1/Th2 shift.

Probiotics and immunity: provisional role for personalized diets and disease prevention

There is great interest in the interaction between diet and immune system and concomitantly in the potential of probiotic bacteria, especially given recent advances in understanding of gut microbiota effects on health in the context of microbiome research. Following our recent study on bacterial wall elasticity as a predictive measure of phagocytic cellular reactions and related outcomes, a question was raised regarding the scope of the application of these findings in various medical conditions in the context of predictive, preventive, and personalized medicine (PPPM). This summarizing review of the data describes the contributions, both observed and potential, of probiotics to the gut-brain axis and various medical conditions, including immune and atopic states, metabolic and inflammatory diseases—including liver disease and diabetes mellitus—cancer, and more. It also suggests novel insights for a number of beneficial applications of probiotics and advances in development of novel probiotic-based treatments and personalized diets, as well as application of sophisticated imaging techniques and nanobiotechnologies that can be adopted in the near future by innovative medical experts, warranting further research and practical translation.

An Evaluation of Non-Surgical Periodontal Therapy in Patients with Rheumatoid Arthritis

aim of this study was to evaluate the efficacy of periodontal scaling and oral hygiene instruction for patients with mild chronic periodontitis and rheumatoid arthritis through clinical periodontal parameters and laboratory tests for CRP (C- reactive protein) and ESR (erythrocyte sedimentation rate). Twelve individuals with rheumatoid arthritis and 12 healthy individuals were evaluated, with a mean age of 45.38 and 46.75 respectively, all female and with mild, chronic periodontitis. The participants were evaluated clinically and periapical radiographs were taken (T1), after which periodontal treatment was instituted. After ninety days (T2), new clinical and laboratory data were obtained. Probing depth, bleeding index, and plaque indexes were observed in both groups, and the results demonstrated reductions but no statistical differences. Laboratory tests for CRP and ESR produced higher values for the rheumatoid arthritis group with T1- T2 reductions on the average, but the values were still higher than in the health group. We conclude that periodontal therapy in patients with rheumatoid arthritis and mild chronic periodontitis showed a improvement in the periodontal clinical parameters and laboratory tests that were evaluated.

GM-CSF and uPA are required for Porphyromonas gingivalis-induced alveolar bone loss in a mouse periodontitis model

Granulocyte-macrophage colony-stimulating factor (GM-CSF) and urokinase-type plasminogen activator (uPA) can contribute to the progression of chronic inflammatory diseases with possible involvement of macrophages. In this study, we investigated the role of both GM-CSF and uPA in Porphyromonas gingivalis-induced experimental periodontitis using GM-CSF-/- and uPA-/- mice. Intra-oral inoculation of wild-type (WT) C57BL/6 mice with P. gingivalis resulted in establishment of the pathogen in plaque and a significant increase in alveolar bone resorption. The infected mice also exhibited a CD11b(+) CD86(+) macrophage infiltrate into the gingival tissue, as well as P. gingivalis-specific pro-inflammatory cytokine and predominantly IgG2b antibody responses. In comparison, intra-oral inoculation of P. gingivalis did not induce bone resorption and there was significantly less P. gingivalis recovered from plaque in GM-CSF-/- and uPA-/- mice. Furthermore, P. gingivalis did not induce a macrophage gingival infiltrate or activate isolated peritoneal macrophages from the gene-deficient mice. Pro-inflammatory P. gingivalis-specific T-cell cytokine responses and serum interferon-gamma (IFN-γ) and IgG2b concentrations were significantly lower in GM-CSF-/- mice. In uPA-/- mice, T-cell responses were lower but serum IFN-γ and IgG2b levels were comparable with WT mice levels. These results suggest that GM-CSF and uPA are both involved in the progression of experimental periodontitis, possibly via a macrophage-dependent mechanism(s).

Methamphetamine effects on blood-brain barrier structure and function

Methamphetamine (Meth) is a widely abuse psychostimulant. Traditionally, studies have focused on the neurotoxic effects of Meth on monoaminergic neurotransmitter terminals. Recently, both in vitro and in vivo studies have investigated the effects of Meth on the BBB and found that Meth produces a decrease in BBB structural proteins and an increase in BBB permeability to various molecules. Moreover, preclinical studies are validated by clinical studies in which human Meth users have increased concentrations of toxins in the brain. Therefore, this review will focus on the structural and functional disruption of the BBB caused by Meth and the mechanisms that contribute to Meth-induced BBB disruption. The review will reveal that the mechanisms by which Meth damages dopamine and serotonin terminals are similar to the mechanisms by which the blood-brain barrier (BBB) is damaged. Furthermore, this review will cover the factors that are known to potentiate the effects of Meth (McCann et al., 1998) on the BBB, such as stress and HIV, both of which are co-morbid conditions associated with Meth abuse. Overall, the goal of this review is to demonstrate that the scope of damage produced by Meth goes beyond damage to monoaminergic neurotransmitter systems to include BBB disruption as well as provide a rationale for investigating therapeutics to treat Meth-induced BBB disruption. Since a breach of the BBB can have a multitude of consequences, therapies directed toward the treatment of BBB disruption may help to ameliorate the long-term neurodegeneration and cognitive deficits produced by Meth and possibly even Meth addiction.

Citrullination and autoimmunity

Autoimmune diseases are characterized by the body's own immune system attack to the self-tissues, a condition enabled, in predisposed subjects, by the reduction of self-tolerance. A central role has been recently recognized to post-translational modifications, since they can promote generation of neo-(auto)antigens and in turn an autoimmune response. During the last years great attention has been paid to citrullination, because of its role in inducing anti-citrullinated proteins/peptide antibodies (ACPA), a class of autoantibodies with diagnostic, predictive and prognostic value for Rheumatoid Arthritis (RA). Nonetheless, citrullination has been reported to be a process present in a wide range of inflammatory tissues. Indeed, citrullinated proteins have been detected also in other inflammatory arthritides and in inflammatory conditions other than arthritides (polymyositis, inflammatory bowel disease and chronic tonsillitis). Moreover, environmental exposure to cigarette smoke and nanomaterials of air pollution may be able to induce citrullination in lung cells prior to any detectable onset of inflammatory responses, suggesting that protein citrullination could be considered as a sign of early cellular damage. Accordingly, citrullination seems to be implicated in all those para-physiological processes, such as cells death pathways, in which intracellular calcium concentration raises to higher levels than in physiologic conditions: hence, peptidylarginine deiminases enzymes are activated during apoptosis, autophagy and NETosis, processes which are well-known to be implicated in autoimmunity. Taken together, these data support the hypothesis that rather than being a disease-dependent process, citrullination is an inflammatory-dependent condition that plays a central role in autoimmune diseases.