Association Between the Extent of Periodontal Inflammation and the Severity of Rheumatoid Arthritis in Japanese Patients With Rheumatoid Arthritis

Synovial macrophages drive severe joint destruction in established rheumatoid arthritis

To investigate the synovial pathological predictors associated with the progression to severe bone erosion in patients with established rheumatoid arthritis (RA). This retrospective study analyzed 41 active RA patients with a disease duration of more than 24 months at our center between March and December 2023. All of these patients underwent synovial biopsy to obtain synovial tissue. These patients were divided into two groups (mild group and severe group) based on the severity of bone erosion assessed by plain X-ray. HE and immunohistochemical staining for CD3, CD20, CD68, and CD138 were conducted on synovium. Stained cells positive for these markers were observed under microscope. the number of positive cells per 20× high-power field in the sublining layer was recorded for each marker. The mild group consisted of 25 patients (23 females) with a median age of 58 years and a median disease duration of 114 months. The severe group included 16 patients (13 females) with a median age of 56 years and a median disease duration of 120 months. There were no significant differences between the mild and severe groups in terms of age, gender, disease duration, RF, ACPA, ESR, and CRP (P > 0.05). However, the disease activity score in 28 joints (DAS-28) of severe group were significantly higher than mild group (5.16 vs. 4.53, P = 0.010). Inflammatory infiltration score observed with HE staining was significantly higher in severe group (P = 0.033), whereas synovial hyperplasia, neovascularization, and stromal activation did not show significant differences between the two groups. The results of immunohistochemistry revealed significantly higher expression of synovial CD68-positive cells in severe group. Multivariable logistic regression analysis showed that synovial CD68-positive cells (OR = 1.020, P = 0.011) were independent risk factors for progressive bone erosion in RA. Synovial macrophage infiltration is an independent risk factor leading to severe progression of bone erosion in RA.

Immunological landscape of periodontitis and rheumatoid arthritis and their molecular crosstalk

BACKGROUND

The association between periodontitis (PT) and rheumatoid arthritis (RA) is well-established; however, the molecular mechanisms underlying this relationship remain poorly understood. This study aims to delineate shared genetic and molecular features between PT and RA to uncover potential common pathways involved in their pathogenesis.

METHODS

Gene expression data sets for PT and RA were retrieved from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) and co-expressed gene modules were identified using weighted gene co-expression network analysis (WGCNA) and the DESeq2 package. Enrichment analyses, including KEGG and Gene Ontology (GO) pathways, as well as immune cell infiltration profiling, were performed to explore shared biological pathways. A protein-protein interaction (PPI) network was constructed to pinpoint key genes linking PT and RA. Functional assays were conducted by overexpressing the identified core gene, PTPRC, in MH7A cells via lentiviral transfection, followed by cell viability (CCK-8), migration, and invasion assays. In addition, transcription factor enrichment and connectivity map (cMAP) analyses were employed to identify common transcriptional regulators and potential therapeutic targets for both conditions.

RESULTS

WGCNA and DESeq2 analyses revealed 154 shared DEGs between PT and RA, predominantly enriched in immune and inflammatory response pathways. PTPRC emerged as a pivotal shared gene, exhibiting significantly higher expression in PT patients compared to controls. In vitro assays confirmed that PTPRC overexpression enhanced fibroblast proliferation, migration, and invasion. Furthermore, transcription factor enrichment analysis and cMAP identified overlapping transcriptional regulators and potential pharmacological agents for both diseases.

CONCLUSIONS

This study provides novel insights into shared gene expression profiles and molecular mechanisms linking PT and RA, identifying PTPRC as a potential key regulator. These findings suggest that targeting PTPRC could offer therapeutic opportunities for RA driven by PT.

Synoviocyte detachment: an overlooked yet crucial histological aspect in rheumatoid arthritis

OBJECTIVE

Rheumatoid arthritis (RA) is a prevalent autoimmune disorder that leads to chronic joint inflammation, deformity, disability, and systemic complications. This study aimed to analyze the clinical characteristics and synovial pathology of RA patients with synoviocyte detachment, and explore the factors associated with this phenomenon.

METHODS

This was a retrospective cohort study included RA patients who underwent synovial biopsy at our center from April to September 2023. Demographic, clinical, laboratory, and synovial histological data were retrospectively collected from medical records at the time of joint synovial biopsy in patients. Microscopic examination of hematoxylin and eosin (HE)-stained synovial tissue sections categorized the samples into synoviocyte detachment and no-synoviocyte detachment groups. Clinical characteristics and synovial pathological changes were compared between the two groups, and the factors associated with synoviocyte detachment were explored through logistic regression analysis.

RESULTS

Fifty-five RA patients were enrolled; 45 were females, and the mean age was 53.4 ± 11.8 years. Nine RA patients exhibited synoviocyte detachment. A total of 46 RA patients in the no-synoviocyte detachment group (15 with a normal lining layer and 31 with synovial cell proliferation) were included. Compared with the no-synoviocyte detachment group, the synoviocyte detachment group presented higher RF, ESR, CRP and DAS28-CRP levels (P < 0.05). The synoviocyte detachment group exhibited more prominent neovascularization (P < 0.05). ESR, DAS28-CRP and synovial neovascularization were risk factors associated with synoviocyte detachment in RA patients.

CONCLUSION

RA patients with synoviocyte detachment exhibit elevated clinical disease activity, marked by pronounced synovial pathology featuring increased neovascularization and less inflammatory cell infiltration. A significant reduction in lymphocyte count compared with patients with synovial cell proliferation was also observed.

Impact of treatment of rheumatoid arthritis on periodontal disease: A review

BACKGROUND

Numerous studies support a bidirectional association between rheumatoid arthritis (RA), a chronic autoimmune degenerative inflammatory joint disease, and periodontitis, a chronic inflammatory disease caused by the immune reaction to bacteria organized in biofilms. RA and periodontitis are both multifactorial chronic inflammatory diseases that share common modifiable and non-modifiable risk factors. There is no cure for RA; treatment is based on lifestyle modifications and a variety of medications: nonsteroidal anti-inflammatory drugs (NSAID), glucocorticoids, and disease-modifying antirheumatic drugs (DMARDs, e.g., conventional synthetic DMARDs [csDMARDs]; biological DMARDs [bDMARD] and targeted synthetic DMARDs). There are molecular pathways of inflammation that are common to both RA and periodontitis. Thus, there is a potential effect of RA treatments on periodontitis. This systematic review aims to assess the impact of antirheumatic agents on periodontal conditions of patients suffering from both RA and periodontitis.

METHODS

PubMed/MEDLINE, Cochrane Library, and Embase online databases were systematically explored, and a manual search was performed to identify relevant studies published until January 2023. This review is registered in the PROSPERO database (CRD42023409006).

RESULTS

A total of 2827 articles were identified, and 35 fulfilled the inclusion criteria. The included studies generally show a consensus that, at normal dosage, NSAID and corticosteroids have negligible impact on periodontium. Similarly, csDMARD alone or in combination with other csDMARD demonstrated no adverse effect on periodontium. Monotherapy with bDMARD had a positive effect on periodontal pocket depths and gingival inflammation in the longitudinal studies up to 6 months but showed negligible effect on the periodontium in interventional studies with a longer follow-up (9 months and 15.1 months). However, the combination of tumor necrosis factor (TNF)-α inhibitors + methotrexate (MTX) was associated with a rise in gingival inflammation. Due to the considerable heterogeneity of the study designs, a meta-analysis could not reasonably be performed.

CONCLUSION

Within the limitations of the available studies, there is evidence to suggest that bDMARD monotherapy may improve the periodontal condition of RA patients with periodontal disease to a certain extent; the concomitant medication of TNF inhibitor + MTX could worsen gingival inflammation. More data are required to understand the impact of RA therapies on periodontal health.

Periodontitis and periodontopathic bacteria as risk factors for rheumatoid arthritis: A review of the last 10 years

Rheumatoid arthritis (RA) is characterized by chronic inflammatory destruction of joint tissue and is caused by an abnormal autoimmune response triggered by interactions between genetics, environmental factors, and epigenetic and posttranslational modifications. RA has been suggested to be interrelated with periodontitis, a serious form or stage of chronic inflammatory periodontal disease associated with periodontopathic bacterial infections, genetic predisposition, environmental factors, and epigenetic influences. Over the last decade, a number of animal and clinical studies have been conducted to assess whether or not periodontitis and associated periodontopathic bacteria constitute risk factors for RA. The present review introduces recent accumulating evidence to support the associations of periodontitis and periodontopathic bacteria with the risk of RA or the outcome of RA pharmacological treatment with disease-modifying antirheumatic drugs. In addition, the results from intervention studies have suggested an improvement in RA clinical parameters after nonsurgical periodontal treatment. Furthermore, the potential causal mechanisms underlying the link between periodontitis and periodontopathic bacteria and RA are summarized.

Periodontal Inflamed Surface Area (PISA) associates with composites of salivary cytokines

BACKGROUND

Periodontal disease (PerioD) is a chronic, complex inflammatory condition resulting from the interaction between subgingival dysbiotic bacteria and the host immune response leading to local inflammation. Since periodontal inflammation is characterized by multiple cytokines effects we investigated whether Periodontal Inflamed Surface Area (PISA), a continuous measure of clinical periodontal inflammation is a predictor of composite indexes of salivary cytokines.

METHODS AND FINDINGS

In a cross-sectional study of 67 healthy, well-educated individuals, we evaluated PISA and several cytokines expressed in whole stimulated saliva. Two salivary cytokine indexes were constructed using weighted and unweighted approaches based on a Principal Component Analysis [named Cytokine Component Index (CCI)] or averaging the (standardized) level of all cytokines [named Composite Inflammatory Index (CII)]. In regression analysis we found that PISA scores were significantly associated with both salivary cytokine constructs, (CCI: part R = 0.51, p<0.001; CII: part R = 0.40, p = 0.001) independent of age, gender and BMI showing that single scores summarizing salivary cytokines correlated with severity of clinical periodontal inflammation.

CONCLUSIONS

Clinical periodontal inflammation may be reflected by a single score encompassing several salivary cytokines. These results are consistent with the complexity of interactions characterizing periodontal disease. In addition, Type I error is likely to be avoided.

Functional Impairment and Periodontitis in Rheumatoid Arthritis

Background

This study explored the association of functional impairment due to rheumatoid arthritis (RA) and RA disease activity with periodontal disease in patients with RA.

Methods

Ninety-three patients with RA were included. Their RA functional status was assessed using the Steinbrocker classification. The serum level of matrix metalloproteinase-3 (MMP-3) was used as an indicator of RA disease activity. Probing depth (PD) and clinical attachment level (CAL) were used as indicators of periodontal status. We examined the association of RA severity and MMP-3 levels with periodontal status using a generalised linear model (GLM).

Results

In a multivariate GLM, the coefficient for the mean PD was significantly positive in those with RA severity classes III or IV (reference: class I; β = 0.14; 95% confidence interval [CI], 0.03–0.25; P = .02) independent of other confounding variables. In multivariate GLM using the mean CAL as the dependent variable, the coefficient was significant in patients with high MMP-3 levels (10 ng/mL; β = 0.005; 95% CI, 0.001–0.008; P = .02).

Conclusions

Functional impairment due to RA may affect PD, and high serum levels of MMP-3 may affect CAL.

Clinical Observations of Osteoporosis in Japanese Patients with Rheumatoid Arthritis

Osteoporosis is the one of the major adverse outcomes in patients with rheumatoid arthritis (RA). Recently, we and others have been reported many clinical observations related to osteoporosis in Japanese RA patients. In this article, I reviewed these findings. Japanese patients with RA have a two-fold risk of fractures compared with those without RA. Among the fractures in Japanese RA patients, three quarters of the fractures were non-vertebral fractures. The incidence of non-vertebral fractures did not change, despite an improvement in RA disease activity. Older age, female gender, history of fractures, history of total knee replacements, disease activity scores in 28 joints (DAS28), health assessment questionnaire disability index (HAQ-DI), low bone mineral density, glucocorticoid dose, and vitamin D deficiency were significantly associated with fractures. Older age, high body mass index (BMI), HAQ-DI, and polypharmacy were significantly associated with falls. BMI (both overweight and underweight), DAS28, and HAQ-DI were significantly associated with frailty. Half and three quarters of Japanese men and women with RA had vitamin D deficiency, respectively. The incidence of osteonecrosis of the jaw may be higher in Japanese RA patients than those without RA. Undertreatment of osteoporosis appears to exist in Japanese patients with RA.

Periodontal inflamed surface area is associated with hs-CRP in septuagenarian Japanese adults in cross-sectional findings from the SONIC study

Periodontal disease is a chronic inflammatory condition that affects various peripheral organs. The periodontal inflamed surface area (PISA) quantifies periodontitis severity and the spread of inflammatory wounds. This study aimed to investigate the association between PISA and high-sensitivity C-reactive protein (hs-CRP), a systemic inflammation marker. This study included 250 community-dwelling septuagenarians (69-71 years). We collected information on their medical (e.g., diabetes and dyslipidemia) and dental examinations (e.g., measurement of the probing pocket depth). Generalized linear model analysis was used to explore the association between PISA and hs-CRP levels. There was a significant difference in hs-CRP levels between groups with PISA ≥ 500 and < 500 (p = 0.017). Moreover, the generalized linear model analysis revealed a significant association between PISA and hs-CRP levels (risk ratio = 1.77; p = 0.033) even after adjusting other factors. Further, we found a correlation between PISA and hs-CRP (Spearman's rank correlation coefficient, rs = 0.181; p = 0.023). Our findings suggest that PISA is an effective index for estimating the effect of periodontitis on the whole body, enabling medical-dental cooperation.

Comparison of periodontal parameters between patients with ischemic and dilative cardiomyopathy

Background

This cross-sectional study aimed in the comparison of periodontal parameters, number of remaining teeth and oral behaviour between patients with ischemic- (ICM) and non-ischemic dilative cardiomyopathy (DCM).

Methods

Patients with HF from the Department for Cardiac Surgery at the Heart Center Leipzig were included. The two groups (ICM and DCM) were composed by matching according to age, gender and smoking habits. All participants received a comprehensive periodontal examination, including a periodontal probing on six measurement points of each tooth.

Results

A total of 226 patients (n = 113 each group) was included. Patients in DCM group used interdental cleaning significantly more often than ICM (23.9% vs. 12.5%, p = 0.04). The majority of patients in both groups (ICM: 83.6%, DCM: 84.6%, p = 0.23) were diagnosed with stage III–IV periodontitis. Periodontal parameters were comparable between groups (p > 0.05). Variance analysis revealed no influence of the group (ICM vs. DCM) on the number of remaining teeth (p = 0.16), periodontitis stage (p = 0.27) or the periodontal inflamed surface area (p = 0.62).

Conclusions

Patients with severe HF show high periodontal burden, without any differences between ICM and DCM group. Therefore, increased attention should be payed to periodontal health of patients with severe heart disease, irrespective of their underlying disease.