Rheumatoid arthritis

CD5L induces inflammation and survival in RA-FLS through ERK1/2 MAPK pathway

OBJECTIVE

To explore the effect of CD5-like molecule (CD5L) on rheumatoid arthritis (RA) fibroblast-like synoviocytes (RA-FLS) and the relative molecular mechanism of CD5L in it.

METHODS

Recombinant protein CD5L was used to stimulate the cultured RA-FLS cells. The inflammation-related cytokines were determined by real time-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). The signal molecules and apoptosis-related molecules were detected by western blot assay (WB), and cell counting kit-8 (CCK-8) was used to detect the proliferation.

RESULTS

CD5L can increase the production of IL-6, IL-8, and TNF-α and this effect can be inhibited by signal pathway inhibitor. At the same time, CD5L activated ERK1/2 MAPK signal, inhibitor treatment can weaken the intensity of phosphorylation. In addition, CD5L can enhance the proliferation ability of RA-FLS.

CONCLUSION

CD5L induces the production of inflammatory cytokines in RA-FLS through the ERK1/2 MAPK pathway and increases cell survival.

Evaluation of genetic polymorphisms in TNF‑α‑308G/A rs1800629 associated with susceptibility and severity of rheumatoid arthritis: A systematic review and meta‑analysis

To investigate the association of gene polymorphisms of TNF-α-308G/A rs1800629 with the susceptibility and severity of rheumatoid arthritis (RA), literature from PubMed, EMBASE, Web of Science and CNKI databases was searched. Two authors screened the literature independently, extracted data and evaluated the risk of bias of the included studies. According to the inclusion and exclusion criteria, five genetic models were established: The allelic model (A vs. G), dominant model (GA + AA vs. GG), recessive model (AA vs. GG + GA), co-dominant model (AA vs. GG) and super-dominant model (GG + AA vs. GA). Stata 17.0 software was used for the meta-analysis. A total of 34 eligible studies with 12,611 subjects were included, including 6,030 cases in the RA group and 6,581 controls. Meta-analysis calculations revealed that the genetic polymorphisms of TNF-α-308G/A rs1800629 were not significantly associated with susceptibility to RA, with an odds ratio and 95% confidence interval (CI) for each genetic model [A vs. G: 0.937 (0.762-1.152); GA + AA vs. GG: 0.918 (0.733-1.148); AA vs. GG + GA: 1.131 (0.709-1.802); AA vs. GG: 1.097 (0.664-1.813); and GG + AA vs. GA: 1.108 (0.894-1.373)]. For the association between TNF-α-308G/A rs1800629 gene polymorphisms and the severity of RA, the results of subgroup analysis calculations showed that TNF-α-308G/A rs1800629 gene polymorphisms were associated with the severity of RA in European populations, with the gene model and 95% CI [GA + AA vs. GG: 0.503 (0.297-0.853); and GG + AA vs. GA: 2.268 (1.434-3.590)]. When assessing the confidence in the positive results of the present study through the false-positive report probability, the positive results were observed to be reliable. No significant association was observed between genetic polymorphisms in TNF-α-308G/A rs1800629 and susceptibility to RA. However, a significant association exists with the severity of RA in European populations.

Itaconate reduces proliferation and migration of fibroblast-like synoviocytes and ameliorates arthritis models

Fibroblast-like synoviocytes (FLS) play critical roles in rheumatoid arthritis (RA). Itaconate (ITA), an endogenous metabolite derived from the tricarboxylic acid (TCA) cycle, has attracted attention because of its anti-inflammatory, antiviral, and antimicrobial effects. This study evaluated the effect of ITA on FLS and its potential to treat RA. ITA significantly decreased FLS proliferation and migration in vitro, as well as mitochondrial oxidative phosphorylation and glycolysis measured by an extracellular flux analyzer. ITA accumulates metabolites including succinate and citrate in the TCA cycle. In rats with type II collagen-induced arthritis (CIA), intra-articular injection of ITA reduced arthritis and bone erosion. Irg1-deficient mice lacking the ability to produce ITA had more severe arthritis than control mice in the collagen antibody-induced arthritis. ITA ameliorated CIA by inhibiting FLS proliferation and migration. Thus, ITA may be a novel therapeutic agent for RA.

Different gender of oxidative balance score on the risk of rheumatoid arthritis in the US population from NHANES

BACKGROUND

Oxidative stress is associated with risk of pathogenesis between rheumatoid arthritis. The Oxidative Balance Score (OBS) is a systematic tool to assess the effects of diet and lifestyle in relation to oxidative stress. However, the association between OBS and rheumatoid arthritis has not been reported previously. We conducted a cross-sectional study to investigate the complex association between OBS and rheumatoid arthritis in US adults.

METHODS

Overall, 9747 participants were included in this cross-sectional study. The exposure variable was OBS, which was scored by 16 dietary and four lifestyle factors. Multivariate logistic regression, subgroup analysis, and restricted cubic spline (RCS) regression were used to analyze the association between OBS and rheumatoid arthritis.

RESULTS

Compared to the lowest OBS quartile group (Q1), the multivariate corrected odds ratio (OR) (95% confidence interval [CI]) for the highest quartile of OBS (Q4) was 0.69 (0.52-0.90) (p = .013 for trend); furthermore, the RCS showed a negative linear relationship between OBS and rheumatoid arthritis. According to subgroup and RCS analyses, there was a significant difference between the association of OBS and with rheumatoid arthritis in terms of gender (p = .049).

CONCLUSION

In conclusion, high OBS was negatively associated with the risk of rheumatoid arthritis. Gender has an effect on OBS in RA. Our results suggest that OBS can be used as a biomarker to predict rheumatoid arthritis.

IL-26 Potentiates Type 2 Skin Inflammation in the Presence of IL-1β

Atopic dermatitis (AD) is a debilitating inflammatory skin disorder. Biologics targeting the IL-4/IL-13 axis are effective in AD, but there is still a large proportion of patients who do not respond to IL-4R blockade. Further exploration of potentially pathogenic T-cell-derived cytokines in AD may lead to new effective treatments. This study aimed to investigate the downstream effects of IL-26 on skin in the context of type 2 skin inflammation. We found that IL-26 alone exhibited limited inflammatory activity in the skin. However, in the presence of IL-1β, IL-26 potentiated the secretion of TSLP, CXCL1, and CCL20 from human epidermis through Jak/signal transducer and activator of transcription signaling. Moreover, in an in vivo AD-like skin inflammation model, IL-26 exacerbated skin pathology and locally increased type 2 cytokines, most notably of IL13 in skin T helper cells. Neutralization of IL-1β abrogated IL-26-mediated effects, indicating that the presence of IL-1β is required for full IL-26 downstream action in vivo. These findings suggest that the presence of IL-1β enables IL-26 to be a key amplifier of inflammation in the skin. As such, IL-26 may contribute to the development and pathogenesis of inflammatory skin disorders such as AD.

Identification of shared disease marker genes and underlying mechanisms between rheumatoid arthritis and Crohn disease through bioinformatics analysis

As chronic autoimmune inflammatory diseases, rheumatoid arthritis (RA) and Crohn disease (CD) are closely associated and display a significant positive correlation. However, the underlying mechanisms and disease markers responsible for their cooccurrence remain unknown and have not been systematically studied. Therefore, this study aimed to identify key molecules and pathways commonly involved in both RA and CD through bioinformatic analysis of public sequencing databases. Datasets for RA and CD were downloaded from the GEO database. Overlapping genes were identified using weighted gene co-expression network analysis and differential analysis crossover, and enrichment analysis was conducted for these genes. Protein-protein interaction networks were then constructed using these overlapping genes to identify hub genes. Expression validation and receiver operating characteristic curve validation were performed for these hub genes using different datasets. Additionally, the immune cell correlation, single-cell expression cluster, and the immune cell expression cluster of the core gene were analyzed. Furthermore, upstream shared microRNAs (miRNA) were predicted and a miRNA-gene network was constructed. Finally, drug candidates were analyzed and predicted. These core genes were found to be positively correlated with multiple immune cells that are infiltrated by the disease. Analysis of gene expression clusters revealed that these genes were mostly associated with inflammatory and immune responses. The miRNA-genes network analysis suggested that hsa-miR-31-5p may play an important role in the common mechanism of RA and CD. Finally, tamibarotene, retinoic acid, and benzo[a]pyrene were identified as potential treatment options for patients with both RA and CD. This bioinformatics study has identified ITGB2, LCP2, and PLEK as key diagnostic genes in patients with both RA and CD. The study has further confirmed that inflammation and immune response play a central role in the development of both RA and CD. Interestingly, the study has highlighted hsa-miR-31-5p as a potential key player in the common mechanism of both diseases, representing a new direction in research and a potential therapeutic target. These shared genes, potential mechanisms, and regulatory networks offer new opportunities for further research and may provide hope for future treatment of patients with both RA and CD.

Belonging, happiness, freedom and empowerment-a qualitative study of patients' understanding of health in early rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is a chronic, systemic, inflammatory joint disease, that influences patients' health in different ways, including physical, social, emotional, and psychological aspects. The goal of rheumatology care is to achieve optimal health and personalised care and therefore, it is essential to understand what health means for patients in the early course of RA. The aim of this study was to describe the understanding of health among patients with early RA.

METHODS

The study had a descriptive qualitative design with a phenomenographic approach. Phenomenography is used to analyse, describe, and understand various ways people understand or experience a phenomenon, in this study, patients' understandings of health. Individual semi-structured interviews were conducted with 31 patients (22 women and nine men, aged (38-80) with early RA, defined as a disease duration of < 1 year, and disease-modifying anti-rheumatic drugs (DMARDs) for 3-7 months. The phenomenographic analysis was conducted in 7 steps, and the outcome space presents the variation in understanding and the interrelation among categories. In accordance with the European Alliance of Associations for Rheumatology's (EULAR) recommendations, a patient research partner participated in all phases of the study.

RESULTS

The analysis revealed four main descriptive categories: 'Health as belonging' was described as experiencing a sense of coherence. 'Health as happiness' was understood as feeling joy in everyday life. 'Health as freedom' was understood as feeling independent. 'Health as empowerment' was understood as feeling capable. Essential health aspects in early RA are comprised of a sense of coherence, joy, independence, and the capability to manage everyday life.

CONCLUSIONS

This study revealed that patients' perception of health in early RA encompasses various facets, including a sense of belonging, happiness, freedom, and empowerment. It highlighted that health is multifaceted and personal, emphasizing the importance of acknowledging this diversity in providing person-centred care. The findings can guide healthcare professionals to deepen patients' participation in treatment goals, which may lead to better treatment adherence and health outcomes.

Autoimmune diseases and atherosclerotic cardiovascular disease

Autoimmune diseases are associated with a dramatically increased risk of atherosclerotic cardiovascular disease and its clinical manifestations. The increased risk is consistent with the notion that atherogenesis is modulated by both protective and disease-promoting immune mechanisms. Notably, traditional cardiovascular risk factors such as dyslipidaemia and hypertension alone do not explain the increased risk of cardiovascular disease associated with autoimmune diseases. Several mechanisms have been implicated in mediating the autoimmunity-associated cardiovascular risk, either directly or by modulating the effect of other risk factors in a complex interplay. Aberrant leukocyte function and pro-inflammatory cytokines are central to both disease entities, resulting in vascular dysfunction, impaired resolution of inflammation and promotion of chronic inflammation. Similarly, loss of tolerance to self-antigens and the generation of autoantibodies are key features of autoimmunity but are also implicated in the maladaptive inflammatory response during atherosclerotic cardiovascular disease. Therefore, immunomodulatory therapies are potential efficacious interventions to directly reduce the risk of cardiovascular disease, and biomarkers of autoimmune disease activity could be relevant tools to stratify patients with autoimmunity according to their cardiovascular risk. In this Review, we discuss the pathophysiological aspects of the increased cardiovascular risk associated with autoimmunity and highlight the many open questions that need to be answered to develop novel therapies that specifically address this unmet clinical need.

Food safety assessment and 28-day toxicity study of the synbiotic Medical Food consortium SBD121

The human gut microbiome plays a crucial role in immune function. The synbiotic consortium or Defined Microbial Assemblage™ (DMA™) Medical Food product, SBD121, consisting of probiotic microbes and prebiotic fibers was designed for the clinical dietary management of rheumatoid arthritis. A 28-day repeated administration study was performed to evaluate the oral toxicity of SBD121 in male and female rats (age/weight at study start: 60 days/ 156-264 grams) administered levels of 0, 4.96 x 1010, 2.48 x 1011, or 4.96 x 1011 colony forming units (CFU)/kg-bw. No treatment related changes in ophthalmological effects, mortality, morbidity, general health and clinical observations, urinalysis, hematology, serum chemistry, absolute or relative organ weights, gross necropsy, or histopathology. A significant decrease in body weight was reported in females in the low and high-concentration groups, which corresponded in part with a significant decrease in food consumption. Results of the functional observation battery indicated front grip strength was significantly greater in the high-concentration males compared to the controls; however, this effect was not considered adverse. Based on these findings, the administration of the Medical Food SBD121 to male and female rats has a no-observable adverse effect level (NOAEL) at the highest level tested of 4.96 x 1011 CFU/kg-bw.

MDSCs are important osteoclast precursors primed by B cells in rheumatoid arthritis

Osteoclast-mediated bone erosion and deformation represent significant pathological features in rheumatoid arthritis (RA). Myeloid-derived suppressor cells (MDSCs) and B cells have emerged as key contributors to the progression of RA. Nevertheless, their involvement, especially the interaction in RA osteoclastogenesis remains elusive. In this study, our results revealed a marked expansion of MDSCs in RA patients, and importantly, their abundance was positively correlated with radiographic damage evaluated by the Sharp/van der Heijde score. Notably, MDSCs derived from both RA patients and arthritic mice exhibited a heightened propensity to differentiate into osteoclasts compared with those from healthy individuals. Intriguingly, we observed that B cells from RA patients could augment the osteoclastogenic potential of MDSCs, which was also observed in arthritic mice. The impact of B cells on MDSC-mediated osteoclastogenesis was found to be most pronounced in switched memory B cells, followed by CD21low B cells and naïve B cells. MDSCs from B-cell-deficient mice exhibited diminished capacity to differentiate into osteoclasts, accompanied by distinct gene expression profiles associated with osteoclastogenesis. Taken together, our findings suggested that MDSCs were important osteoclast precursors primed by B cells in RA, serving as novel therapeutic targets for the persistent disease.

Single-cell analysis in rheumatic and allergic diseases: insights for clinical practice

Since the advent of single-cell RNA sequencing (scRNA-seq) methodology, single-cell analysis has become a powerful tool for exploration of cellular networks and dysregulated immune responses in disease pathogenesis. Advanced bioinformatics tools have enabled the combined analysis of scRNA-seq data and information on various cell properties, such as cell surface molecular profiles, chromatin accessibility and spatial information, leading to a deeper understanding of pathology. This Review provides an overview of the achievements in single-cell analysis applied to clinical samples of rheumatic and allergic diseases, including rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, allergic airway diseases and atopic dermatitis, with an expanded scope beyond peripheral blood cells to include local diseased tissues. Despite the valuable insights that single-cell analysis has provided into disease pathogenesis, challenges remain in translating single-cell findings into clinical practice and developing personalized treatment strategies. Beyond understanding the atlas of cellular diversity, we discuss the application of data obtained in each study to clinical practice, with a focus on identifying biomarkers and therapeutic targets.

Work-related support for employed and self-employed people with rheumatoid arthritis or axial spondyloarthritis: a cross-sectional online survey of patients

BACKGROUND

Little is known about the provision of work-related support for (self-)employed people with rheumatoid arthritis (RA) or axial spondyloarthritis (axSpA) by healthcare providers (HCPs) or employers.

OBJECTIVE

This study aims to explore the experiences of (self-)employed people with RA or axSpA regarding work-related support from HCPs and employers in the Netherlands.

METHODS

This cross-sectional study concerned an online survey for (self-)employed people, aged ≥ 16 years and diagnosed with RA or axSpA. The survey focused on experiences with HCPs and employers' work-related support and included questions on sociodemographic factors, health and work characteristics and work-related problems.

RESULTS

The survey was completed by 884 participants, 56% with RA and 44% with axSpA, of whom 65% were employed, 8% self-employed and 27% not employed. In total, 95% (589/617) of (self-)employed participants reported work-related problems. Sixty-five percent of employed and 56% of self-employed participants had discussed these work-related problems with rheumatologists and/or other HCPs. Whereas 69% of employees with their employer. Both employed and self-employed participants reported that work-related advices or actions were more often provided by other HCPs (53%) than rheumatologists (29%). Fifty-six percent of employees reported this work-related support by the employer.

CONCLUSION

This survey among (self-)employed people with RA or axSpA found that the majority reported work-related problems, but only half of them received any work-related support for these problems. Discussion of work-related problems with HCPs was more often reported by employed than self-employed participants. More attention from especially rheumatologists and other HCPs is important to identify and address work-related problems promptly.

Therapeutic potential of probiotics in gut microbial homeostasis and Rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by inflammation and joint damage. Existing treatment options primarily focus on managing symptoms and slowing disease progression, often with side effects and limitations. The gut microbiome, a vast community of microorganisms present in the gastrointestinal tract, plays a crucial role in health and disease. Recent research suggests a bidirectional relationship between the gut microbiome and RA, highlighting its potential as a therapeutic option. This review focuses on the interaction between the gut microbiome and RA development, by discussing how dysbiosis, an imbalance in gut bacteria, can contribute to RA through multiple mechanisms such as molecular mimicry, leaky gut, and metabolic dysregulation. Probiotics, live microorganisms with health benefits, are emerging as promising tools for managing RA. They can prevent the negative effects of dysbiosis by displacing harmful bacteria, producing anti-inflammatory metabolites like short-chain fatty acids (SCFA), Directly influencing immune cells, and modifying host metabolism. animal and clinical studies demonstrate the potential of probiotics in improving RA symptoms and disease outcomes. However, further research is needed to optimize probiotic strains, dosages, and treatment protocols for personalized and effective management of RA. This review summarizes the current understanding of the gut microbiome and its role in RA and discusses future research directions. In addition to the established role of gut dysbiosis in RA, emerging strategies like fecal microbiota transplantation, prebiotics, and postbiotics offer exciting possibilities. However, individual variations in gut composition necessitate personalized treatment plans. Long-term effects and clear regulations need to be established. Future research focusing on metagenomic analysis, combination therapies, and mechanistic understanding will unlock the full potential of gut microbiome modulation for effective RA management.

Polyclonally Derived Alloantigen-Specific T Regulatory Cells Exhibit Target-Specific Suppression and Capture MHC Class II from Dendritic Cells

Foxp3+ T regulatory (Treg) cells prevent allograft rejection and graft-versus-host disease. Although polyclonal Tregs have been used both in animal models and in humans, the fine specificity of their suppressive function is poorly defined. We have generated mouse recipient-derived alloantigen-specific Tregs in vitro and explored the fine specificity of their suppressive function and their mechanism of action in vitro and in vivo. In vitro, when alloantigen and peptide Ag were both presented on the same dendritic cell, both responses were suppressed by iTregs specific either for the alloantigen or for the peptide Ag. In vivo, iTreg suppression was limited to the cognate Ag, and no bystander suppression was observed when both allo-antigen and peptide Ag were present on the same dendritic cell. In vitro, alloantigen-specific Tregs captured cognate MHC but failed to capture noncognate MHC. Our results demonstrate that a polyclonal population of iTregs generated from naive T cells can mediate highly specific function in vivo and support the view that Treg therapy, even with unselected polyclonal populations, is likely to be target antigen-specific and that bystander responses to self-antigens or to infectious agents are unlikely.

Unveiling Novel Drug Targets and Emerging Therapies for Rheumatoid Arthritis: A Comprehensive Review

Rheumatoid arthritis (RA) is a chronic debilitating autoimmune disease, that causes joint damage, deformities, and decreased functionality. In addition, RA can also impact organs like the skin, lungs, eyes, and blood vessels. This autoimmune condition arises when the immune system erroneously targets the joint synovial membrane, resulting in synovitis, pannus formation, and cartilage damage. RA treatment is often holistic, integrating medication, physical therapy, and lifestyle modifications. Its main objective is to achieve remission or low disease activity by utilizing a "treat-to-target" approach that optimizes drug usage and dose adjustments based on clinical response and disease activity markers. The primary RA treatment uses disease-modifying antirheumatic drugs (DMARDs) that help to interrupt the inflammatory process. When there is an inadequate response, a combination of biologicals and DMARDs is recommended. Biological therapies target inflammatory pathways and have shown promising results in managing RA symptoms. Close monitoring for adverse effects and disease progression is critical to ensure optimal treatment outcomes. A deeper understanding of the pathways and mechanisms will allow new treatment strategies that minimize adverse effects and maintain quality of life. This review discusses the potential targets that can be used for designing and implementing precision medicine in RA treatment, spotlighting the latest breakthroughs in biologics, JAK inhibitors, IL-6 receptor antagonists, TNF blockers, and disease-modifying noncoding RNAs.

A Review of Advances in Molecular Imaging of Rheumatoid Arthritis: From In Vitro to Clinic Applications Using Radiolabeled Targeting Vectors with Technetium-99m

Rheumatoid arthritis (RA) is a systemic autoimmune disorder caused by inflammation of cartilaginous diarthrodial joints that destroys joints and cartilage, resulting in synovitis and pannus formation. Timely detection and effective management of RA are pivotal for mitigating inflammatory arthritis consequences, potentially influencing disease progression. Nuclear medicine using radiolabeled targeted vectors presents a promising avenue for RA diagnosis and response to treatment assessment. Radiopharmaceutical such as technetium-99m (99mTc), combined with single photon emission computed tomography (SPECT) combined with CT (SPECT/CT), introduces a more refined diagnostic approach, enhancing accuracy through precise anatomical localization, representing a notable advancement in hybrid molecular imaging for RA evaluation. This comprehensive review discusses existing research, encompassing in vitro, in vivo, and clinical studies to explore the application of 99mTc radiolabeled targeting vectors with SPECT imaging for RA diagnosis. The purpose of this review is to highlight the potential of this strategy to enhance patient outcomes by improving the early detection and management of RA.

CT informs detection and treatment options in rheumatoid arthritis complicated by pulmonary non-tuberculous mycobacterial disease from the FIRST registry

OBJECTIVE

To investigate the early detection of pulmonary non-tuberculous mycobacterial (PNTM) disease by CT before the initiation of molecular-targeted therapeutic drugs in patients with rheumatoid arthritis (RA) and the efficacy and safety of combined treatment with antibiotics.

METHODS

Patients with RA underwent chest CT before the introduction of molecular-targeted therapies in the Further Improvement of Rheumatoid arthritis Treatment registry. The primary endpoint was the number of patients who were detected by CT as having PNTM disease, complicating RA.

RESULTS

Of 4447 patients with RA who underwent chest CT, 107 had suspected PNTM disease, and 33 diagnoses were confirmed by culture. In 14 of the 33 patients, plain radiographs showed no abnormalities; PNTM disease was only observed on CT scans. The prevalence of PNTM disease in patients with RA requiring molecular-targeted treatment was six times higher than that in healthy individuals. 31 patients initiated molecular-targeted therapeutic drugs in combination with anti-NTM treatment, and 28 were followed up for 24 months. No significant difference was observed in the retention rate and RA disease activity at 24 months between the PNTM and non-PNTM groups. Coexisting PNTM disease did not affect treatment discontinuation. None of the 28 patients in the PNTM group experienced exacerbation of PNTM disease.

CONCLUSION

CT screening before the initiation of molecular-targeted treatment enabled the detection of asymptomatic PNTM that was undetectable on plain radiographs. This study showed that molecular-targeted therapeutic drugs in combination with anti-NTM treatment could control the disease activity of both PNTM and RA.

The Lung in Rheumatoid Arthritis-Friend or Enemy?

Rheumatoid arthritis (RA) is a chronic autoimmune condition frequently found in rheumatological patients that sometimes raises diagnosis and management problems. The pathogenesis of the disease is complex and involves the activation of many cells and intracellular signaling pathways, ultimately leading to the activation of the innate and acquired immune system and producing extensive tissue damage. Along with joint involvement, RA can have numerous extra-articular manifestations (EAMs), among which lung damage, especially interstitial lung disease (ILD), negatively influences the evolution and survival of these patients. Although there are more and more RA-ILD cases, the pathogenesis is incompletely understood. In terms of genetic predisposition, external environmental factors act and subsequently determine the activation of immune system cells such as macrophages, neutrophils, B and T lymphocytes, fibroblasts, and dendritic cells. These, in turn, show the ability to secrete molecules with a proinflammatory role (cytokines, chemokines, growth factors) that will produce important visceral injuries, including pulmonary changes. Currently, there is new evidence that supports the initiation of the systemic immune response at the level of pulmonary mucosa where the citrullination process occurs, whereby the autoantibodies subsequently migrate from the lung to the synovial membrane. The aim of this paper is to provide current data regarding the pathogenesis of RA-associated ILD, starting from environmental triggers and reaching the cellular, humoral, and molecular changes involved in the onset of the disease.

Double-crosslinked self-healing hydrogel alleviates osteoarthritis by protecting from wearing and targeting NF-kB signaling

Osteoarthritis (OA) is a chronic disease that causes pain, morbidity, and disability. The main strategy for OA treatment focuses on inflammation suppression, inhibition of osteoclastogenesis, and protection of articular cartilage. These functions cannot be performed effectively by monotherapy. Therefore, an effective drug delivery system is required, capable of containing and controlling the efflux of various drugs to alleviate osteoclastogenesis, protect cartilage and subchondral bone, and suppress inflammation. In this work, an encapsulation system is constructed using a self-healing chitosan hydrogel and allocated compound drugs. The self-healing gel is composed of branched-functionalized chitosan, created by simultaneously using polycaprolactone polyethylene glycol azide as a block polymer and the host-guest assembly of β-cyclodextrin and adamantane. Inhibitors of the NFkB pathway are loaded into the cavities of β-cyclodextrin and the spring-like structure of the block polymer, which can be rapidly released upon joint friction (due to the reassembly of β-cyclodextrin and adamantane by shear stress and the stretch of the block polymer). In vitro experiments using BMMs and the ATDC5 cell line confirm that the developed hydrogel can simultaneously suppress osteoclastogenesis and induce chondrogenesis. Additionally, a model of knee arthritis in C57 mice was used to confirm that this double-crosslinked encapsulation system can lubricate the knee joint surface and provide adequate protection on demand through shear-responsive drug release.

The time of equipoise on the use of biological DMARDs in for inflammatory arthritis during pregnancy is finally over: a reappraisal of evidence to optimise pregnancy management

Active inflammatory arthritis in pregnancy is associated with an increased risk of adverse pregnancy outcomes. Treatment of active inflammation and maintenance of low disease activity with medication reduces these risks. Therapeutic decisions on disease-modifying antirheumatic drugs (DMARDs) in pregnancy are complicated by safety concerns, which have led to inappropriate withdrawal of treatment and consequential harm to mother and fetus. Studies of inflammatory arthritis in pregnancy have consistently shown minimal safety concerns with the use of biological DMARDs and an increased risk of disease flare with discontinuation of biological DMARDs. It is our opinion that during pregnancy, the benefits of disease control with biological DMARDs, when required in addition to conventional synthetic DMARDs, outweigh the risks. In this Series paper, we review the reasons for reconsideration of equipoise and propose an agenda for future research to optimise the use of biological DMARDs in inflammatory arthritis during pregnancy.

Inflammatory diseases causing joint and bone destruction: rheumatoid arthritis and hemophilic arthropathy

Various diseases and conditions cause joint disorders. Osteoarthritis (OA) is characterized by the degeneration of articular cartilage, synovitis, and anabolic changes in surrounding bone tissues. In contrast, rheumatoid arthritis (RA) and hemophilic arthropathy (HA) display marked destruction of bone tissues caused by synovitis. RA is a representative autoimmune disease. The primary tissue of RA pathogenesis is the synovial membrane and involves various immune cells that produce catabolic cytokines and enzymes. Hemophilia is a genetic disorder caused by a deficiency in blood clotting factors. Recurrent intra-articular bleeding leads to chronic synovitis through excessive iron deposition and results in the destruction of affected joints. Although the triggers for these two joint diseases are completely different, many cytokines and enzymes are common in the pathogenesis of both RA and HA. This review focuses on the similarities between joint and bone destruction in RA and HA. The insights may be useful in developing better treatments for hemophilia patients with arthropathy and osteoporosis by leveraging advanced therapeutics for RA.

A bidirectional autoimmune cluster between vitiligo and rheumatoid arthritis: a large-scale population-based study

A knowledge gap exists regarding the association between vitiligo and rheumatoid arthritis (RA) due to the absence of large-scale cohort studies designed to investigate this association. To investigate the bidirectional epidemiological association between vitiligo and RA. A population-based study was conducted using Clalit Health Services (CHS) database (2002-2019) using both a cohort study and a case-control study design. Adjusted hazard ratio (HR) and odds ratio (OR) were calculated by multivariate Cox and logistic regressions, respectively. Overall, 20,851 vitiligo patients and 102,475 controls were included. The incidence of new-onset RA was 4.1 (95% CI 3.0-5.4) and 2.9 (95% CI 2.4-3.3) cases per 10,000 person-years among patients with vitiligo and controls, respectively. Patients with vitiligo had a significantly increased risk of developing new-onset RA (adjusted HR, 1.44; 95% confidence interval [CI], 1.02-2.02, P = 0.036). The likelihood of having vitiligo was significantly elevated after a preexisting diagnosis of RA (adjusted OR, 1.67; 95% CI, 1.38-2.03; P < 0.001). Relative to the remaining patients with vitiligo, those with vitiligo and comorbid RA demonstrated an elevated risk of all-cause mortality (adjusted HR, 1.61; 95% CI, 1.03-2.51; P = 0.037). Our study confirms the bidirectional association between vitiligo and RA. Physicians treating patients with vitiligo should be aware of the association in clinical practice.

Vitamin C alleviates rheumatoid arthritis by modulating gut microbiota balance

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by chronic and symmetric in-flammation. Our previous research revealed an imbalance in the gut flora of RA patients and showed that certain gut microbiota can accelerate RA progression by enhancing vitamin C degradation. However, it is unclear whether vitamin C supplementation could improve the gut microbiota to prevent the development of arthritis by interfering with the gut-joint axis. In this work, we aimed to evaluate the effects of vitamin C in regulating the gut microbiota and to elucidate its potential role in the onset and progression of RA in a mouse model, thus providing a basis for the development of new intervention strategies and treatments for RA. In this study, collagen-induced arthritis (CIA) mouse models, biochemical, histological and 16S rRNA microbiological methods were used to investigate the role and possible mechanism of vitamin C in rheumatoid arthritis. The results showed that treatment of CIA mice with vitamin C effectively rescued the gut mi-crobiota imbalance and suppressed the inflammatory response associated with RA, and effectively alleviated arthritis symptoms in mice in which levels of the pro-inflammatory cytokines IL-6 and TNF-α were specifi-cally reduced. In conclusion, our results demonstrate the potential of vitamin C as a potential therapeutic choice for RA.

Trends in prevalence of arthritis by race among adults in the United States, 2011-2018

BACKGROUND

There is currently a lack of comprehensive prevalence information on arthritis and its various classifications among adults in the U.S., particularly given the notable absence of detailed data regarding the Asian population. We examined the trends in the prevalence of arthritis, including osteoarthritis (OA), rheumatoid arthritis (RA), psoriatic arthritis (PsA), and other types of arthritis, among U.S. adults by race between 2011 and 2018.

METHODS

We analyzed data from the National Health and Nutrition Examination Survey (NHANES), spanning from 2011 to 2018. Our study focused on a nationally representative sample of U.S. adults aged 20 and older. Participants who answered "y es" to the research question "Doctors ever said you had arthritis?" were classified as having arthritis. Further classification into specific diseases was based on responses to the question "Which type of arthritis was it?" with options including "OA or degenerative arthritis, " "RA, " "PsA, " or "Other. " RESULTS: We analyzed 22,566 participants from NHANES (2011-2018), averaging 44.8 years, including 10,927 males. The overall arthritis prevalence rose significantly from 22.98% (95% CI: 21.47-24.55%) in 2011-12 to 27.95% (95% CI: 26.20-29.76%) in 2017-18 (P for trend < 0.001). OA increased from 12.02% (95% CI: 10.82-13.35%) in 2011 to 14.93% (95% CI: 13.47-16.51%) in 2018 (P for trend < 0.001). RA and PsA remained stable (P for trend = 0.220 and 0.849, respectively), while other arthritis rose from 2.03% (95% CI: 1.54-2.67%) in 2011-12 to 3.14% (95% CI: 2.56-3.86%) in 2017-18 (P for trend = 0.001). In Whites, Asians, and other races , arthritis and RA prevalence increased significantly (P for trend < 0.05). OA and other arthritis rose in Whites and other races (P for trend < 0.05), but no significant change occurred in the black population. The prevalence of PsA remained stable across all racial groups, with no statistically significant changes.

CONCLUSIONS

In this nationally representative U.S. adult survey spanning 2011 to 2018, we identified a rising prevalence trend in arthritis, OA, and other arthritis, with notable variations among different racial groups.

Delivery technologies for therapeutic targeting of fibronectin in autoimmunity and fibrosis applications

Fibronectin (FN) is a critical component of the extracellular matrix (ECM) contributing to various physiological processes, including tissue repair and immune response regulation. FN regulates various cellular functions such as adhesion, proliferation, migration, differentiation, and cytokine release. Alterations in FN expression, deposition, and molecular structure can profoundly impact its interaction with other ECM proteins, growth factors, cells, and associated signaling pathways, thus influencing the progress of diseases such as fibrosis and autoimmune disorders. Therefore, developing therapeutics that directly target FN or its interaction with cells and other ECM components can be an intriguing approach to address autoimmune and fibrosis pathogenesis.

The potential pathogenic role of gut microbiota in rheumatic diseases: a human-centred narrative review

A growing amount of evidence suggests that gut microbiota plays an important role in human health, including a possible role in the pathogenesis of rheumatic and musculoskeletal diseases (RMD). We analysed the current evidence about the role of microbiota in rheumatoid arthritis (RA), spondyloarthritis (SpA), systemic lupus erythematosus (SLE) and systemic sclerosis (SSc). In RA, we found a general consensus regarding a reduction of diversity and a specific bacterial signature, with consistent changes according to the different ethnic and geographical areas. The major pathogenetic role in RA is recognised for P. copri, L. salivarius and Collinsella, even if findings become more heterogeneous when considering established disease. In SpA, we found a relative gut abundance of Akkermansia, Coprococcus, Ruminoccocus and a relative reduction in Bacterioides and Firmicutes spp. Human and preclinical data suggest loss of mucosal barrier, increased permeability and Th1- and Th17-mediated inflammation. Additionally, HLA-B27 seems to play a role in shaping the intestinal microbiota and the consequent inflammation. In SLE, the typical gut microbiota signature was characterised by a reduction in the Firmicutes/Bacteroidetes ratio and by enrichment of Rhodococcus, Eggerthella, Klebsiella, Prevotella, Eubacterium and Flavonifractor, even if their real pathogenic impact remains unclear. In SSc, gastrointestinal dysbiosis is well documented with an increase of pro-inflammatory species (Fusobacterium, Prevotella, Ruminococcus, Akkermansia, γ-Proteobacteria, Erwinia, Trabsulsiella, Bifidobacterium, Lactobacillus, Firmicutes and Actinobacteria) and a reduction of species as Faecalibacterium, Clostridium, Bacteroidetes and Rikenella. In conclusion, seems possible to recognise a distinct gut microbiota profile for each RMD, even if significant differences in bacterial species do exist between different studies and there is a high risk of bias due to the cross-sectional nature of such studies. Therefore longitudinal studies are needed, especially on patients with preclinical and early disease, to investigate the real role of gut microbiota in the pathogenesis of RMD.

Patients' and rheumatologists' perceptions on dose reduction of rituximab in rheumatoid arthritis

OBJECTIVE

The recommended dose of a rituximab course for the treatment of Rheumatoid Arthritis (RA) consists of two infusions of 1000 mg with a 2-week interval. Evidence is growing that a lower dose could be as effective. We aimed to investigate patients' and rheumatologists' perceptions on dose reduction of rituximab.

METHODS

Patients with RA treated with rituximab, and rheumatologists were invited for a qualitative study via individual semi-structured interviews. Participants were recruited based on purposive sampling to ensure diversity. Interviews were analysed according to the principles of grounded theory and the constant comparative method.

RESULTS

Sixteen patients and 13 rheumatologists were interviewed. Patients and rheumatologists perceived the benefits of rituximab dose reduction for reasons of safety and societal costs. Furthermore, available evidence for the effectiveness of lower doses was mentioned as an argument in favour, in addition to the possibility to tailor the dose based on the patients' clinical manifestations. However, patients and rheumatologists had concerns about the potential loss of effectiveness and quality of life. Moreover, some rheumatologists felt uncomfortable with dose reduction due to insufficient experience with rituximab in general. Patients and rheumatologists emphasised the importance of shared decision-making, underscoring the pivotal role of physicians in this process by explaining the reasoning behind dose reduction.

CONCLUSION

Although some concerns on effectiveness were perceived, both patients and rheumatologists saw potential benefits of dose reduction in terms of safety, societal costs, and application of a personalised approach. As a result, most rheumatologists and patients showed a willingness to consider dose reduction strategies.

pH and ROS Dual-Sensitive Nanocarriers for the Targeted Co-Delivery and On-Demand Sequential Release of Tofacitinib and Glucosamine for Synergistic Rheumatoid Arthritis Treatment

Rheumatoid arthritis (RA) progression involves multiple cell types, and sequential drug action on target cells is necessary for RA treatment. Nanocarriers are widely used for RA treatment; however, the targeted delivery and on-demand release of multiple drugs remains challenging. Therefore, in this study, a dual-sensitive polymer is developed using chondroitin sulfate (CS) for the co-delivery of the cartilage repair agent, glucosamine (GlcN), and anti-inflammatory drug, tofacitinib (Tof). In the joint cavity, acidic pH facilitates the cleavage of GlcN from CS polymer to repair the cartilage damage. Subsequently, macrophage uptake via CS-CD44 binding and intracellular reactive oxygen species (ROS) mediate conversion of (methylsulfanyl)propylamine to a hydrophilic segment jointly triggered rapid Tof/GlcN release via micelle disassembly. The combined effects of Tof, GlcN, and ROS depletion promote the M1-to-M2 polarization shift to attenuate inflammation. The synergistic effects of these agents against RA are confirmed in vitro and in vivo. Overall, the dual pH/ROS-sensitive CS nanoplatform simultaneously delivers GlcN and Tof, providing a multifunctional approach for RA treatment with synergistic drug effects.

Investigating the therapeutic potential of sinomenine in rheumatoid arthritis: anti-inflammatory, antioxidant, and immunomodulatory mechanisms

An autoimmune disease, rheumatoid arthritis (RA) is characterized by the onset of inflammation and subsequent damage to the joints. Although several therapies are available for RA, none are effective, and many have undesirable side effects. The roots of Sinomenium acutum produce an alkaloid called Sinomenine (SIN), which has been used for centuries in Chinese medicine to treat arthritis due to its anti-inflammatory properties. This study aimed to explore the potential therapeutic benefits of SIN through oral administration following RA induction using Freund's complete adjuvant (FCA) injections. The study monitored changes in the arthritic index, hind paw volume, inflammation and oxidative stress markers. Results demonstrated that SIN effectively inhibited the activity of NF-κB and IKKβ in knee joint tissues, which led to a decrease in tissue levels of TNF-α, IL-6, IL-1β, and iNOS in RA-induced rats. The production of anti-inflammatory cytokines such as IL-10, Arg-1, and Fizz1 also increased. In rat knee joints, SIN elevated the expression of TIMP-1 and TIMP-3 and decreased the expression of MMP-2 and MMP-9. Additionally, SIN modulated the RANK/RANKL/OPG pathway in RA-induced rat knee joint tissues, reducing RANKL expression and increasing OPG. SIN also effectively decreased MDA, NO, and elevated antioxidant enzymes (SOD, CAT, GPx, and GSH) in RA-induced rats via Nrf2/Keap 1 signaling pathway activation. In conclusion, this study suggests that SIN possesses potential therapeutic benefits for treating RA by modulating the RANK/RANKL/OPG pathway, which may impact osteoclast activity, oxidative stress, and inflammation in knee joint tissues.

Contributions of Synthetic Chemicals to Autoimmune Disease Development and Occurrence

PURPOSE OF REVIEW

Exposure to many synthetic chemicals has been linked to a variety of adverse human health effects, including autoimmune diseases. In this scoping review, we summarize recent evidence detailing the effects of synthetic environmental chemicals on autoimmune diseases and highlight current research gaps and recommendations for future studies.

RECENT FINDINGS

We identified 68 recent publications related to environmental chemical exposures and autoimmune diseases. Most studies evaluated exposure to persistent environmental chemicals and autoimmune conditions including rheumatoid arthritis (RA), systemic lupus (SLE), systemic sclerosis (SSc), and ulcerative colitis (UC) and Crohn's disease. Results of recent original research studies were mixed, and available data for some exposure-outcome associations were particularly limited. PFAS and autoimmune inflammatory bowel diseases (UC and CD) and pesticides and RA appeared to be the most frequently studied exposure-outcome associations among recent publications, despite a historical research focus on solvents. Recent studies have provided additional evidence for the associations of exposure to synthetic chemicals with certain autoimmune conditions. However, impacts on other autoimmune outcomes, particularly less prevalent conditions, remain unclear. Owing to the ubiquitous nature of many of these exposures and their potential impacts on autoimmune risk, additional studies are needed to better evaluate these relationships, particularly for understudied autoimmune conditions. Future research should include larger longitudinal studies and studies among more diverse populations to elucidate the temporal relationships between exposure-outcome pairs and to identify potential population subgroups that may be more adversely impacted by immune modulation caused by exposure to these chemicals.

Sociodemographic and clinical variables associated with negative illness perception in patients newly diagnosed with rheumatoid arthritis, axial spondyloarthritis, or psoriatic arthritis-a survey based cross-sectional study

When newly diagnosed with inflammatory arthritis (IA), acquiring self-management skills is beneficial, to enhance quality of life. The personal beliefs and mental representations patients hold about their illness, known as illness perception, significantly influence the development of these skills. Recognizing characteristics that affect illness perception is key to identifying patients requiring additional support for the development of self-management skills. This study aimed at identifying the sociodemographic and clinical characteristics associated with a negative illness perception. This cross-sectional study was based on survey data from patients diagnosed for ≤ 2 years. The Brief Illness Perception Questionnaire (B-IPQ) was used to measure illness perception. After psychometric testing, we divided the B-IPQ into two domains: (1) a control domain and (2) a consequence domain. We performed logistic regression analyses with multiple imputations. A total of 1,360 patients (61% females) were included. Among them, 64%, 20%, and 16% were diagnosed with rheumatoid arthritis, psoriatic arthritis (PsA) and axial spondyloarthritis (axSpA), respectively. Younger patients with lower socioeconomic status, a diagnosis of PsA or axSpA, high disease activity (OR 3.026, CI 2.208;4.147), severe physical disability (OR 4.147. CI 2.883;6.007), severe pain (OR 3.034, CI 1.991;4.622), and severe fatigue (OR 2.612, CI 1.942;3.513) were significantly more likely to report having a negative illness perception. Younger patients with a higher symptom burden, increased disease activity, lower socioeconomic status, and a diagnosis of PsA or axSpA may require additional attention and support in rheumatology clinical practice to aid in the development of their self-management skills.

The first involved joints and associated factors in patients with rheumatoid arthritis

Objectives

This study aimed to investigate the first involved joints and associated factors in Turkish patients with rheumatoid arthritis (RA).

Patients and methods

This retrospective cross-sectional study included 300 newly diagnosed and disease-modifying antirheumatic drug-naïve RA patients (240 females, 60 males; mean age: 54±1.2 years; range, 18 to 82 years). Baseline demographic, clinical, and laboratory data were evaluated between January 2022 and December 2022. The patients were divided into four groups according to autoantibody profile: antibody-negative patients (Group 1; both RF and anti-CCP were negative in this group of patients), RF-positive patients (Group 2), anti-CCP-positive patients (Group 3), and patients with dual seropositivity with RF and antiCCP (Group 4). The patients were also divided into two groups according to the size of the first affected joint: patients with SJI at diagnosis and patients without SJI involvement at diagnosis.

Results

Rheumatoid factor (RF) and anti-cyclic citrullinated peptide (CCP) antibody positivity rates were 40.3% and 35.6%, respectively. The mean lag time to diagnosis was 25±36 months. At the disease onset, 20% of patients did not have small joint involvement (SJI). Seronegative patients tended to be female (p=0.001), had longer lag time (p=0.001), and had lower levels of C-reactive protein (p=0.025), white blood count (p=0.005), and neutrophil/lymphocyte ratio (p=0.001) compared to the dual seropositive group. Patients presenting with SJI had a younger age (p=0.002), tended to be female (p=0.001), and had lower RF (p=0.034) and anti-CCP (p=0.031) positivity. Only age (p=0.005) and dual seronegativity (RF and anti-CCP; p=0.035) were the independent predictors of SJI in multivariate analysis.

Conclusion

The decreasing age and seronegative status were defined as independent risk factors of SJI at the onset of RA. Population-based, prospective studies are needed for earlier diagnosis.

Berberine loaded thermosensitive lipid nanoparticles: in vitro characterization, in silico study, and in vivo anti-arthritic effect

Thermoresponsive drug delivery systems have been used to treat diseases that cause hyperthermia or elevated body tissue temperatures, viz., rheumatoid arthritis and different cancers. The aim of the study was to enhance berberine (BER) release using thermosensitive nanostructured lipid carriers (TNLCs) through intra-articular administration for the management of arthritis. TNLCs were prepared using binary mixtures of stearic acid and decanoic acid as solid and liquid lipids, respectively. Lipid mixtures with an optimum melting point were assessed using differential scanning calorimetry studies. In vitro characterization of the BER TNLCs included particle size, zeta potential, entrapment efficiency, and drug release at 37 °C and 41 °C. Joint diameter measurement, real-time polymerase chain reaction (RT-PC) analysis, enzyme-linked immunosorbent assay (ELISA) for inflammatory markers, and histological evaluation of the dissected joints were all performed in vivo on rats with adjuvant-induced arthritis. In vitro characterization revealed negatively charged BER-loaded TNLCs with a spherical shape, particle size less than 500 nm, BER entrapment efficiency up to 79%, and a high drug release rate at an elevated temperature of 41 °C. In silico studies revealed the affinity of BER to different formula components and to the measured biomarkers. In vivo assessment of the optimum TNLCs showed that BER TNLCs were superior to the BER solution suspension regarding their effect on inflammatory biomarkers, joint diameter, and histological studies.

Self-actuating inflammation responsive hydrogel microsphere formulation for controlled drug release in rheumatoid arthritis (RA): Animal trials and study in human fibroblast like synoviocytes (hFLS) of RA patients

Patients with rheumatoid arthritis (RA) often have one or more painfuljoints despite adequate medicine. Local drug delivery to the synovial cavity bids for high drug concentration with minimal systemic adverse effects. However, anti-RA drugs show short half-lives in inflamed joints after intra-articular delivery. To improve the therapeutic efficacy, it is essential to ensure that a drug is only released from the formulation when it is needed. In this work, we developed an intelligent "Self-actuating" drug delivery system where Disease-modifying anti-rheumatic Drug (DMARD) methotrexate is incorporated within a matrix intended to be injected directly into joints. This formulation has the property to sense the need and release medication only when joints are inflamed in response to inflammatory enzyme Matrix metalloproteinases (MMP). These enzymes are important proteases in RA pathology, and several MMP are present in augmented levels in synovial fluid and tissues. A high level of MMP present in synovial tissues of RA patients would facilitate the release of drugs in response and ascertain controlled drug release. The formulation is designed to be stable within the joint environment, but to dis-assemble in response to inflammation. The synthesized enzyme-responsive methotrexate (Mtx) encapsulated micron-sized polymer-lipid hybrid hydrogel microspheres (Mtx-PLHM) was physiochemically characterized and tested in synovial fluid, Human Fibroblast like synoviocytes (h-FLS) (derived from RA patients) and a rat arthritic animal model. Mtx-PLHM can self-actuate and augment the release of Mtx drug upon contact with either exogenously added MMP or endogenous MMP present in the synovial fluid of patients with RA. The drug release from the prepared formulation is significantly amplified to several folds in the presence of MMP-2 and MMP-9 enzymes. In the rat arthritic model, Mtx-PLHM showed promising therapeutic results with the significant alleviation of RA symptoms through decrease in joint inflammation, swelling, bone erosion, and joint damage examined by X-ray analysis, histopathology and immune-histology. This drug delivery system would be nontoxic as it releases more drug only during the period of exacerbation of inflammation. This will simultaneously protect patients from unwanted side effects when the disease is inactive and lower the need for repeated joint injections.

Microenvironment Responsive Hydrogel Exerting Inhibition of Cascade Immune Activation and Elimination of Synovial Fibroblasts for Rheumatoid Arthritis Therapy

Rheumatoid arthritis (RA) is a progressive autoimmune disease and drug therapy has been restricted due to poor therapeutic efficacy and adverse effects. In RA synovium, dendritic cells present self-antigens to activate cascade immune pathway. Furthermore, downstream macrophages secrete high levels of pro-inflammatory cytokines; Hyperplasia of activated synovial fibroblasts (FLS) is responsible for hypoxic synovium microenvironment, secretion of cytokines/chemokines and erosion of bone/cartilage tissues. Positive feedback loop of inflammation between macrophages and FLS independent of antigen-presentation is constructed. Herein, an injectable pH-sensitive peptide hydrogel encapsulating siRNA/Methotrexate-polyethyleneimine (siMP, including sip65MP, sip38MP, siCD86MP) and Bismuthene nanosheet/Methotrexate-polyethyleneimine (BiMP) is successfully developed. Among them, siCD86MP reduces protein level of co-stimulatory molecule CD86 while sip65MP and sip38MP separately inhibit NF-κB and MAPK-p38 pathways of macrophages and FLS to suppress secretion of cytokines and MMPs. Meanwhile, reduction in anti-apoptotic property of FLS induced by inhibition of NF-κB pathway has a synergistic effect with photodynamic therapy (PDT) and photothermal therapy (PTT) mediated by BiMP for FLS elimination, effectively ameliorating hypoxic synovium microenvironment. After being injected into synovium, hydrogel responds to acidic microenvironment and serves as a reservoir for sustained drug release and inherent retention capacity of which enables cationic nanoparticles to bypass tissue barrier for precise synovium targeting. This brand-new drug delivery system combines modulating cascade immune pathway from beginning to end by RNAi and eliminating FLS for improving synovium microenvironment by phototherapy together, providing a robust strategy for clinical RA treatment.

Association between Mediterranean-dietary approaches to stop hypertension intervention for neurodegenerative delay diet and biomarkers of oxidative stress, metabolic factors, disease severity, and odds of disease in rheumatoid arthritis patients

This research aimed to examine the association between the following Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) dietary pattern and oxidative stress indicators, metabolic factors, disease activity, and the odds of disease in patients with rheumatoid arthritis (RA). In this cross-sectional study, we included 101 patients with RA and 101 healthy individuals. The MIND diet score was measured using a semi-quantitative Food Frequency Questionnaire (FFQ) with 147 food items. Total capacity antioxidant (TCA), superoxide dismutase (SOD), glutathione peroxidase (GPX), and malondialdehyde (MDA) serum concentrations were evaluated by ELISA, and the disease severity was measured regarding the disease activity score 28 (DAS-28) criteria. The average score of the MIND diet was substantially lower in the RA subjects than in the healthy people (p < .001). Individuals with a higher MIND diet score had lower odds of RA than those with a low score (p < .001). There was no remarkable link between the MIND diet and oxidative stress factors (p > .05). A reverse association was found between the MIND diet score and disease activity (p < .05). The MIND diet was significantly and negatively correlated with triglycerides, low-density lipoprotein cholesterol, total cholesterol, fasting blood glucose, and hemoglobin A1C. There was a positive association between the diet and high-density lipoprotein cholesterol. The findings indicate that following the MIND diet may decrease disease activity and the odds of RA. Also, high adherence to the MIND diet may improve the lipid profile and blood glucose status in RA patients.

Evaluating the docetaxel effect in an animal model of polyarthritis

Rheumatoid arthritis (RA) is immune-mediated, inflammatory disease that affects synovial joints, and characterized by inflammatory changes in synovial tissue, cartilage, bone, and less commonly in extra-articular structures. Docetaxel (DTX) is a semi-synthetic anti-neoplastic medication. Peptidyl-arginine deiminase type 4 (PAD4) is expressed in macrophages and neutrophils in RA synovial membrane. Their effectiveness is in producing anti-cyclic citrullinated peptide antibodies (ACPA)-targeted citrullinated neoepitopes.

AIM

To evaluate the anti-inflammatory effects of DTX in RA and the effect of methotrexate on PAD4 to investigate its potential as an RA biomarker.

METHODS

Forty male Wistar rats were divided into five groups of eight rats. Healthy rats formed the control group. The Second Group to Fifth group were induced with Complete Freund's adjuvant. The third group received DTX at a dosage of 1 mg/kg on alternate days, as determined by a preliminary experiment. The fourth group was given 1 mg/kg/week of methotrexate intraperitoneally. The fifth group was treated with a half dose of DTX and methotrexate simultaneously.

RESULTS

Significant Arthritis index and knee joint circumference decrease in the DTX group. No significant difference in body weight, platelet-lymphocyte ratio, and white blood cell count between the groups. Neutrophile lymphocyte ratio showed weak correlation with ACPA, while PAD4 showed good correlation with RA markers. Level of ACPA, PAD4, TNF-α, IL-1β, and VEGF significantly decreased in the DTX group than induction group (p < 0.05).

CONCLUSION

DTX reduces the progression and joint destruction in rats induced by Complete Freund's Adjuvant which may due to inhibition of PAD4, TNF-α, IL-1β, VEGF, and ACPA. Also, methotrexate exhibited anti PAD4 effect.

The role of YAP/TAZ on joint and arthritis

Osteoarthritis (OA) and rheumatoid arthritis (RA) are two common forms of arthritis with undefined etiology and pathogenesis. Yes-associated protein (YAP) and its homolog transcriptional coactivator with PDZ-binding motif (TAZ), which act as sensors for cellular mechanical and inflammatory cues, have been identified as crucial players in the regulation of joint homeostasis. Current studies also reveal a significant association between YAP/TAZ and the pathogenesis of OA and RA. The objective of this review is to elucidate the impact of YAP/TAZ on different joint tissues and to provide inspiration for further studying the potential therapeutic implications of YAP/TAZ on arthritis. Databases, such as PubMed, Cochran Library, and Embase, were searched for all available studies during the past two decades, with keywords "YAP," "TAZ," "OA," and "RA."

Global pattern, trend, and cross-country inequality of early musculoskeletal disorders from 1990 to 2019, with projection from 2020 to 2050

BACKGROUND

This study aims to estimate the burden, trends, forecasts, and disparities of early musculoskeletal (MSK) disorders among individuals ages 15 to 39 years.

METHODS

The global prevalence, years lived with disabilities (YLDs), disability-adjusted life years (DALYs), projection, and inequality were estimated for early MSK diseases, including rheumatoid arthritis (RA), osteoarthritis (OA), low back pain (LBP), neck pain (NP), gout, and other MSK diseases (OMSKDs).

FINDINGS

More adolescents and young adults were expected to develop MSK disorders by 2050. Across five age groups, the rates of prevalence, YLDs, and DALYs for RA, NP, LBP, gout, and OMSKDs sharply increased from ages 15-19 to 35-39; however, these were negligible for OA before age 30 but increased notably at ages 30-34, rising at least 6-fold by 35-39. The disease burden of gout, LBP, and OA attributable to high BMI and gout attributable to kidney dysfunction increased, while the contribution of smoking to LBP and RA and occupational ergonomic factors to LBP decreased. Between 1990 and 2019, the slope index of inequality increased for six MSK disorders, and the relative concentration index increased for gout, NP, OA, and OMSKDs but decreased for LBP and RA.

CONCLUSIONS

Multilevel interventions should be initiated to prevent disease burden related to RA, NP, LBP, gout, and OMSKDs among individuals ages 15-19 and to OA among individuals ages 30-34 to tightly control high BMI and kidney dysfunction.

FUNDING

The Global Burden of Disease study is funded by the Bill and Melinda Gates Foundation. The project is funded by the Scientific Research Fund of Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital (2022QN38).

Clonal hematopoiesis driven by mutated DNMT3A promotes inflammatory bone loss

Clonal hematopoiesis of indeterminate potential (CHIP) arises from aging-associated acquired mutations in hematopoietic progenitors, which display clonal expansion and produce phenotypically altered leukocytes. We associated CHIP-DNMT3A mutations with a higher prevalence of periodontitis and gingival inflammation among 4,946 community-dwelling adults. To model DNMT3A-driven CHIP, we used mice with the heterozygous loss-of-function mutation R878H, equivalent to the human hotspot mutation R882H. Partial transplantation with Dnmt3aR878H/+ bone marrow (BM) cells resulted in clonal expansion of mutant cells into both myeloid and lymphoid lineages and an elevated abundance of osteoclast precursors in the BM and osteoclastogenic macrophages in the periphery. DNMT3A-driven clonal hematopoiesis in recipient mice promoted naturally occurring periodontitis and aggravated experimentally induced periodontitis and arthritis, associated with enhanced osteoclastogenesis, IL-17-dependent inflammation and neutrophil responses, and impaired regulatory T cell immunosuppressive activity. DNMT3A-driven clonal hematopoiesis and, subsequently, periodontitis were suppressed by rapamycin treatment. DNMT3A-driven CHIP represents a treatable state of maladaptive hematopoiesis promoting inflammatory bone loss.

High fat diet increases the severity of collagen-induced arthritis in mice by altering the gut microbial community

OBJECTIVES

Research has demonstrated that obesity may be associated with rheumatoid arthritis (RA). In addition, gut microbiota and its metabolites contribute to the occurrence and development of RA and obesity. However, the mechanism by which obesity affects RA remains unclear. In this study, we aimed to investigate whether gut microbiota and their metabolites alter the effects of high fat diet (HFD) on the severity of collagen-induced arthritis (CIA) in mice.

METHODS

Briefly, mice were divided into normal group (N), CIA model group (C), HFD group (T), and HFD CIA group (CT). Hematoxylin and Eosin staining(HE) and Safranin O-fast green staining were conducted, and levels of blood lipid and inflammatory cytokines were measured. 16S rDNA sequencing technique and liquid chromatography-mass spectrometry (LC-MS)-based metabolomics were performed to explore changes in the microbiota structure to further reveal the pathomechanism of HFD on CIA.

RESULTS

HFD aggravated the severity of CIA in mice. The CT group had the highest proportion of microbial abundance of Blautia, Oscillibacter, Ruminiclostridium-9, and Lachnospiraceae UCG 006 at the genus level, but had a lower proportion of Alistipes. Additionally, the fecal metabolic phenotype of the combined CT group shows significant changes, with differential metabolites enriched in 9 metabolic pathways, including primary bile acid biosynthesis, arginine biosynthesis, sphingolipid metabolism, purine metabolism, linoleic acid metabolism, oxytocin signaling pathway, aminoacyl-tRNA biosynthesis, the pentose phosphate pathway, and sphingolipid signaling pathway. Correlation analysis revealed that some of the altered gut microbiota genera were strongly correlated with changes in fecal metabolites, total cholesterol (TC), triglyceride (TG), and inflammatory cytokine levels.

CONCLUSIONS

This study shows that HFD may aggravate inflammatory reaction in CIA mice by altering the gut microbiota and metabolic pathways.

Food-derived bioactive peptides potentiating therapeutic intervention in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease that affects the joints of the human body and is projected to have a prevalence age-standardized rate of 1.5 million new cases worldwide by 2030. Several conventional and non-conventional preventive and therapeutic interventions have been suggested but they have their side effects including nausea, abdominal pain, liver damage, ulcers, heightened blood pressure, coagulation, and bleeding. Interestingly, several food-derived peptides (FDPs) from both plant and animal sources are increasingly gaining a reputation for their potential in the management or therapy of RA with little or no side effects. In this review, the concept of inflammation, its major types (acute and chronic), and RA identified as a chronic type were discussed based on its pathogenesis and pathophysiology. The conventional treatment options for RA were briefly outlined as the backdrop of introducing the FDPs that potentiate therapeutic effects in the management of RA.

Comparison and Influence of a Multicomponent Educational Program on the Patient-Reported Outcomes of a Group of Patients With Rheumatoid Arthritis

BACKGROUND

Rheumatoid arthritis (RA) is a chronic disease that affects different areas of the patient's body. Patient education and health literacy is essential for them to participate actively in follow-up.

OBJECTIVES

The aim of this study was to assess differences between clinimetric measurements done by a medical team and patient-reported outcome measures (PROMs) in RA and understand the impact of patient education strategies in order to identify differences between RA assessment methods.

METHODS

This is a longitudinal cohort study. It included adult patients with RA and access to digital tools. These were divided into 3 groups by type of education. Group 1 included patients who participated in a multicomponent RA educational program. Group 2 did not have this multicomponent RA education. Group 3 did not receive any education. The 3 groups performed PROMs. Disease activity scales, functional class, and quality of life were measured. Univariate and bivariate analysis (χ2 and Wilcoxon for paired data) were done.

RESULTS

Twenty-eight patients were included in group 1, 26 in group 2, and 37 in group 3. All were women. In group 1, there were no significant differences in clinimetrics between the medical team and patient's PROMs except for fatigue. In group 2 and group 3, significant differences were found. The RAPID3 and PAS variables did not show significant differences when analyzed by intervention subgroups.

CONCLUSIONS

This study shows no differences between clinimetrics/PROMs for patients with a high-level education on RA and physicians. On the other hand, when patient did not have any RA education, the clinimetric results differed from physician measurement.

Population Pharmacokinetic Analysis and Simulation of Alternative Dosing Regimens for Biosimilars to Adalimumab and Etanercept in Patients with Rheumatoid Arthritis

Efficacy to biologics in rheumatoid arthritis (RA) patients is variable and is likely influenced by each patient's circulating drug levels. Using modelling and simulation, the aim of this study was to investigate whether adalimumab and etanercept biosimilar dosing intervals can be altered to achieve therapeutic drug levels at a faster/similar time compared to the recommended interval. RA patients starting subcutaneous Amgevita or Benepali (adalimumab and etanercept biosimilars, respectively) were recruited and underwent sparse serum sampling for drug concentrations. Drug levels were measured using commercially available kits. Pharmacokinetic data were analysed using a population approach (popPK) and potential covariates were investigated in models. Models were compared using goodness-of-fit criteria. Final models were selected and used to simulate alternative dosing intervals. Ten RA patients starting the adalimumab biosimilar and six patients starting the etanercept biosimilar were recruited. One-compartment PK models were used to describe the popPK models for both drugs; no significant covariates were found. Typical individual parameter estimates were used to simulate altered dosing intervals for both drugs. A simulation of dosing the etanercept biosimilar at a lower rate of every 10 days reached steady-state concentrations earlier than the usual dosing rate of every 7 days. Simulations of altered dosing intervals could form the basis for future personalised dosing studies, potentially saving costs whilst increasing efficacy.

Differences in IDO1+ dendritic cells and soluble CTLA-4 are associated with differential clinical responses to methotrexate treatment in rheumatoid arthritis

Objective

Antigen-presenting dendritic cells (DCs) and monocytes play an essential role in rheumatoid arthritis (RA) pathogenesis, however, their tolerogenic potential remains unclear. Herein, the tolerogenic profiles of DCs are characterized in treatment-naïve RA patients to determine their role to inflammatory arthritis management.

Methods

Thirty-six treatment-naïve RA patients were enrolled, of which 62% were non-responders to methotrexate (MTX) monotherapy based on disease activity score (DAS) after 6-months of therapy. DC and monocyte subset frequencies, activation (CD40, CD86, CD209 expression), and tolerogenic profile (intracellular indoleamine-2,3-dioxygenase [IDO1] and cytotoxic T lymphocyte antigen 4 [CTLA-4] expression) were examined in the baseline peripheral blood by multicolor flow-cytometry. Soluble CTLA-4 (sCTLA-4) levels in plasma were measured.

Results

DC subsets were decreased in RA compared to healthy controls (HC), and the frequency of conventional DCs (cDC) inversely correlated with inflammatory markers and improvement in disease activity. CD141+ cDC1s were the major IDO1-expressing cells. IDO1+cDC1s were reduced in RA patients compared to HC. The baseline frequency of IDO1+cDC1s inversely correlated with improvement in disease activity. CTLA-4 expression in CD1c+ cDC2s and monocytes was lower in RA patients compared to HC. Moreover, MTX-responders had a significantly lower frequency of IDO1+cDC1 cells and higher level of sCTLA-4 in the plasma compared to MTX non-responders. There was a strong predictive association of low IDO1+cDC1 cells, low sCTLA-4 and non-response to MTX.

Conclusions

Our findings reveal altered DC and monocytes immunophenotypes that are associated with RA pathology and treatment response. The frequencies of tolerogenic IDO1+cDC1s and the low level of sCTLA-4 are strongly associated with MTX non-responsiveness and therapeutic outcome. These results suggest that investigation of the association IDO1+cDC1 and sCTLA-4 with response to treatment may be more generalizable to other autoimmune diseases.

New Classification of Rheumatoid Arthritis Based on Immune Cells and Clinical Characteristics

Background

Rheumatoid arthritis (RA) is a chronic systemic immune disease characterized by joint synovitis, but there are differences in clinical manifestations and serum test results among different patients.

Methods

This is a bioinformatics study. We first obtained the gene expression profile of RA and normal synovium from the database, and screened the differentially expressed immune related genes for enrichment analysis. Subsequently, we classified RA into three subtypes by unsupervised clustering of serum gene expression profiles based on immune enrichment scores. Then, the enrichment and clinical characteristics of different subtypes were analyzed. Finally, according to the infiltration of different subtypes of immune cells, diagnostic markers were screened and verified by qRT-PCR.

Results

C1 subtype is related to the increase of neutrophils, C-reactive protein and erythrocyte sedimentation rate, and joint pain is more significant in patients. C2 subtype is related to the expression of CD8+T cells and Tregs, and patients have mild joint pain symptoms. The RF value of C3 subtype is higher, and the expression of various immune cells is increased. CD4 T cells, NK cells activated, macrophages M1 and neutrophils are immune cells significantly infiltrated in synovium and serum of RA patients. IFNGR1, TRAC, IFITM1 can be used as diagnostic markers of different subtypes.

Conclusion

In this study, RA patients were divided into different immune molecular subtypes based on gene expression profile, and immune diagnostic markers were screened, which provided a new idea for the diagnosis and treatment of RA.

The Effects of Exercise Training on Functional Capacity and Quality of Life in Patients with Rheumatoid Arthritis: A Systematic Review

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation. The purpose of this systematic review is to evaluate the effectiveness of exercise training on functional capacity and quality of life (QoL) in patients with RA. We performed a search in four databases, selecting clinical trials that included community or outpatient exercise training programs in patients with RA. The primary outcome was functional capacity assessed by peak VO2 or the 6 min walking test, and the secondary outcome was QoL assessed by questionnaires. Seven studies were finally included, identifying a total number of 448 patients. The results of the present systematic review show a statistically significant increase in peak VO2 after exercise training in four out of seven studies. In fact, the improvement was significantly higher in two out of these four studies compared to the controls. Six out of seven studies provided data on the patients' QoL, with five of them managing to show statistically significant improvement after exercise training, especially in pain, fatigue, vitality, and symptoms of anxiety and depression. This systematic review demonstrates the beneficial effects of exercise training on functional capacity and QoL in patients with RA.

Differences and Similarities in the Feet of Metatarsalgia Patients with and without Rheumatoid Arthritis in Remission

Objectives: Metatarsalgia continues to be a problem in patients with rheumatoid arthritis (RA) in remission (remRA), as well as in the non-rheumatic population, with a mechanical origin. Identify and compare clinical, morphological, disability, synovitis (ultrasound), and radiological osteoarticular damage characteristics in two groups of patients with lesser-ray metar-tarsalgia, with remRA, and without RA. Methods: Cross-sectional study with 84 patients with remRA (mRA) and 60 patients without RA (nmRA). The study evaluated five clinical variables (pain, Foot Function Index (FFI), joint mobility, digital deformities, and foot type), a radiological variable (osteoarticular damage), and an ultrasound variable (metatarsal synovitis). The data were analysed using descriptive and correlational techniques. Results: There were no significant differences in sex, age, body mass index (BMI), or degree of pain. Both groups showed a high prevalence of limited joint mobility for the ankle and first metatarsal phalanx (DF1st MTPJ) and digital deformities, with no statistically significant differences. Similarly, there were no differences in lesser-ray synovitis. On the other hand, there were differences in mRA with greater disability and activity limitation (FFI), LDD (lesser-ray digital deformities) stiffness, first-ray deformities, radiological damage, synovitis in 1st MTPJ, and positive Doppler (five patients). Conclusions: Metatarsalgia presents similarities in both populations. Biomechanical factors may influence the symptoms and presence of synovitis in patients with RA in remission. Other characteristics are more frequent in mRA, which could be related to the disease; thus, future research should include both biomechanical and ultrasound exploration of the foot in the valuation of patients in remission.

The fibroid phenotype of biological naïve patients with rheumatoid arthritis are less likely to respond to anti-IL-6R treatment

Type III collagen gene expression is upregulated in the synovium of patients with rheumatoid arthritis (RA) presenting the fibroid phenotype. The soluble type III collagen formation biomarker, PRO-C3, is known to measure fibrogenesis in fibrotic diseases. In this exploratory study, we aimed to investigate the association between fibrogenesis (PRO-C3) and the disease- and treatment response in patients with RA. We measured PRO-C3 in subsets of two clinical trials assessing the effect of the anti-interleukin-6 (IL-6) receptor treatment tocilizumab (TCZ) as monotherapy or polytherapy with methotrexate. PRO-C3 levels had weak or very weak correlations with the clinical parameters (Spearman's). However, when the patients were divided into Disease Activity Score-28 groups characterized by the erythrocyte sedimentation rate (DAS28-ESR), there was a statistical difference between the PRO-C3 levels of the different groups (p < 0.05). To determine the response in relation to PRO-C3, a cut-off based on PRO-C3 levels and patients in remission (DAS28-ESR ≤ 2.6) was identified. This showed that a reduction in PRO-C3 after treatment initiation was associated with decreased DAS28-ESR and a higher response rate in patients with low PRO-C3 levels than in those with high PRO-C3 levels. This indicates that a fibrotic component affects the responsiveness of patients.