Genetic Background and Molecular Mechanisms of Juvenile Idiopathic Arthritis

Identification and validation of susceptibility modules and hub genes in polyarticular juvenile idiopathic arthritis using WGCNA and machine learning

BACKGROUND

Juvenile idiopathic arthritis (JIA), superseding juvenile rheumatoid arthritis (JRA), is a chronic autoimmune disease affecting children and characterized by various types of childhood arthritis. JIA manifests clinically with joint inflammation, swelling, pain, and limited mobility, potentially leading to long-term joint damage if untreated. This study aimed to identify genes associated with the progression and prognosis of JIA polyarticular to enhance clinical diagnosis and treatment.

METHODS

We analyzed the gene expression omnibus (GEO) dataset GSE1402 to screen for differentially expressed genes (DEGs) in peripheral blood single nucleated cells (PBMCs) of JIA polyarticular patients. Weighted gene co-expression network analysis (WGCNA) was applied to identify key gene modules, and protein-protein interaction networks (PPIs) were constructed to select hub genes. The random forest model was employed for biomarker gene screening. Functional enrichment analysis was conducted using David's online database, gene ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis to annotate and identify potential JIA pathways. Hub genes were validated using the receiver operating characteristic (ROC) curve.

RESULTS

PHLDA1, EGR3, CXCL2, and PF4V1 were identified as significantly associated with the progression and prognosis of JIA polyarticular phenotype, demonstrating high diagnostic and prognostic assessment value.

CONCLUSION

These genes can be utilized as potential molecular biomarkers, offering valuable insights for the early diagnosis and personalized treatment of JIA polyarticular patients.

Attempts to identify the molecular cause of autoinflammatory recurrent fever

Systemic autoinflammatory diseases caused by dysregulation of the innate immunity are a known cause of recurrent fevers. We present the molecular diagnosis results of 12 children with recurrent fever, analyzing the correlation between molecular findings and clinical symptoms. No pathogenic variants confirming autoinflammatory disease were found. One child was diagnosed with SRP54 deficiency, linked to congenital neutropenia with a cyclic pattern. Variants of uncertain significance were found in 6 patients in genes associated with autoinflammatory disorders, though two lacked clinical correlation. Variants of uncertain significance in the NLRC4 gene were detected in 2 patients with periodic fever, aphthous stomatitis, pharyngitis, adenitis (PFAPA) syndrome, in the PLSG2 gene in 1 child with systemic juvenile idiopathic arthritis, and in the MEFV gene in 1 patient with syndrome of uncertain recurrent fever. COVID-19 was identified as a triggering factor in 54.5% of cases. Further research is needed to clarify the role of genetic variants and environmental factors in recurrent fevers.

Amyloidosis in Childhood: A Review of Clinical Features and Comparison with Adult Forms

Amyloidosis is a rare multisystem disorder characterized by extracellular accumulation of insoluble fibrils in various organs and tissues. The most common subtype in the pediatric population is systemic reactive amyloidosis, typically developing secondary to chronic inflammatory conditions and resulting in deposition of serum amyloid A protein in association with apolipoprotein HDL3. Clinical presentation is highly variable and is mostly influenced by specific organs involved, precursor protein type, and extent of amyloid deposition, often closely reflecting clinical features of the underlying disease. The most critical determinants of prognosis are cardiac and renal involvement. Diagnosis of amyloidosis is confirmed by tissue biopsy, which remains the gold standard, followed by precise amyloid fibril typing. The primary therapeutic approach is directed towards controlling underlying disease and reducing serum levels of precursor proteins to prevent further amyloid deposition. This study aims to highlight the main clinical characteristics of amyloidosis with onset in childhood, emphasizing the key differences compared to adult form.

Single-cell transcriptome and crosstalk analysis reveals immune alterations and key pathways in the bone marrow of knee OA patients

Knee osteoarthritis (OA) is a significant medical and economic burden. To understand systemic immune effects, we performed deep exploration of bone marrow aspirate concentrates (BMACs) from knee-OA patients via single-cell RNA sequencing and proteomic analyses from a randomized clinical trial (MILES: NCT03818737). We found significant cellular and immune alterations in the bone marrow, specifically in MSCs, T cells and NK cells, along with changes in intra-tissue cellular crosstalk during OA progression. Unlike previous studies focusing on injury sites or peripheral blood, our probe into the bone marrow-an inflammation and immune regulation hub-highlights remote organ impact of OA, identifying cell types and pathways for potential therapeutic targeting. Our findings highlight increased cellular senescence and inflammatory pathways, revealing key upstream genes, transcription factors, and ligands. Additionally, we identified significant enrichment in key biological pathways like PI3-AKT-mTOR signaling and IFN responses, showing their potentially crucial role in OA onset and progression.

Clinical and laboratory features of juvenile idiopathic arthritis with wrist involvement: Results of a retrospective cohort study

BACKGROUND

Previous studies in the pre-biological era showed an association of wrist inflammation in juvenile idiopathic arthritis (JIA) with progressive disease course, polyarticular involvement and failure of methotrexate treatment.

AIM

To describe features of JIA, associated with wrist arthritis.

METHODS

Data from about 753 JIA patients were included in this retrospective cohort study. The clinical and laboratory features of patients with and without wrist involvement were analyzed.

RESULTS

Wrist involvement was found in oligoarthritis (5.8%), RF(-)/RF(+) polyarthritis (44.9%/15.0%), enthesitis-related arthritis (17.7%), and systemic (58.6%) JIA categories. Unilateral wrist involvement was typical for oligoarthritis patients, bilateral involvement was either equal to that of unilateral involvement or was more frequent in other categories. Wrist arthritis was found to be associated with female sex, a low incidence of uveitis, and more indications of systemic inflammation, including elevated levels of C-reactive protein, erythrocyte sedimentation rate, and platelets, as well as involvement of the cervical spine, temporomandibular, shoulder, elbow, metacarpophalangeal, proximal interphalangeal, distal interphalangeal, hip, ankle, and tarsus arthritis. The number of patients with hip osteoarthritis and hip replacement was also higher. Wrist arthritis was associated with a lower probability of achieving remission [hazard ratio (HR) = 1.3 (95%CI: 1.0-1.7), P = 0.055], and a higher probability of being treated with biologics [HR = 1.7 (95%CI: 1.3-2.10, P = 0.00009)].

CONCLUSION

Wrist arthritis in JIA patients is a marker of a severe disease course, characterized by more intensive inflammation, unfavorable outcomes, and. requiring more intensive treatment with early administration of biologics. Close monitoring of wrist inflammation with ultrasound and MR assessment with early biological treatment might improve the outcomes.

Orthodontic Management of a Patient With Juvenile Idiopathic Arthritis: A Case Report

Juvenile idiopathic arthritis (JIA) is a childhood condition marked by joint inflammation, pain, and restricted movement. It often leads to progressive joint damage. Among systemic inflammatory diseases, JIA most commonly affects the temporomandibular joint (TMJ), posing challenges for orthodontic treatment. This case report presents the successful orthodontic treatment of a 15-year-old patient with Class II malocclusion and JIA. The treatment outcome was excellent and remained stable at the one-year follow-up, with no clinical symptoms or radiographic changes in the TMJ observed.

Association of IL-17A and IL-10 Polymorphisms with Juvenile Idiopathic Arthritis in Finnish Children

To analyze the role of interleukin IL-17A and IL-10 polymorphisms in susceptibility to juvenile idiopathic arthritis (JIA), 98 Finnish children and adolescents with JIA were studied. Data from the 1000 Genomes Project, consisting of 99 healthy Finns, served as the controls. The patients were analyzed for four IL-17A and three IL-10 gene-promoter polymorphisms, and the serum IL-17A, IL-17F, IL-10, and IL-6 levels were determined. The IL-17A rs8193036 variant genotypes (CT/CC) were more common among the patients than controls, especially in those with polyarthritis (OR 1.93, 95% CI 1.11-3.36; p = 0.020). IL-17A rs2275913 minor allele A was more common in patients (OR 1.45, 95% Cl 1.08-1.94; p = 0.014) and especially among patients with oligoarthritis and polyarthritis than the controls (OR 1.61, 95%CI 1.06-2.43; p = 0.024). Carriers of the IL-17A rs4711998 variant genotype (AG/AA) had higher serum IL-17A levels than those with genotype GG. However, carriers of the variant genotypes of IL-17A rs9395767 and rs4711998 appeared to have higher IL-17F levels than those carrying wildtype. IL-10 rs1800896 variant genotypes (TC/CC) were more abundant in patients than in the controls (OR 1.97, 95%CI 1.06-3.70; p = 0.042). Carriers of the IL-10 rs1800896 variant genotypes had lower serum levels of IL-17F than those with wildtype. These data provide preliminary evidence of the roles of IL-17 and IL-10 in the pathogenesis of JIA and its subtypes in the Finnish population. However, the results should be interpreted with caution, as the number of subjects included in this study was limited.

Juvenile idiopathic arthritis and primary ovarian failure: a two-sample Mendelian randomization analysis in a mixed-gender cohort

Background

The causal relationship between juvenile idiopathic arthritis (JIA) and primary ovarian failure (POF) remains uncertain. To elucidate this relationship, we employed a two-sample Mendelian randomization analysis.

Methods

The single nucleotide polymorphisms (SNPs) associated with JIA were obtained from a previously published genome-wide association study (GWAS), while the pooled data for POF originated from the FinnGen consortium. The study populations consisted exclusively of individuals of European descent. In our Mendelian randomization analysis, we performed inverse-variance weighted analysis, weighted-median analysis, weighted-mode analysis and Mendelian randomization-Egger regression analysis, supplemented by sensitivity analyses to validate the accuracy and robustness of the findings.

Results

The IVW (OR = 1.23, 95% CI 1.06-1.43; P = 0.007) and weighted median (OR = 1.25, 95% CI 1.06-1.47; P = 0.009), along with sensitivity analysis validation, provide compelling evidence of a significant causal association between JIA and POF.

Conclusion

The study revealed a significant causal association between genetically predicted JIA and POF, indicating that JIA significantly elevates the risk of developing POF. Therefore, it is recommended to implement screening for premature ovarian failure in women diagnosed with JIA.

Blood brain barrier permeability and astrocyte-derived extracellular vesicles in children with juvenile idiopathic arthritis: a cross-sectional study

BACKGROUND

Juvenile idiopathic arthritis (JIA) is the most prevalent rheumatic disease in children, and the inflammatory process is widely studied, primarily characterized by its impact on joint health. Emerging evidence suggests that JIA may also affect the central nervous system (CNS). This study investigates the potential CNS involvement in JIA by analyzing the presence of astrocyte-derived extracellular vesicles (EVs) and the S100B protein in plasma, both of which are indicative of astrocyte activity and blood-brain barrier (BBB) integrity.

METHODS

EDTA plasma from 90 children diagnosed with JIA and 10 healthy controls, matched by age and gender, was analyzed for extracellular vesicles by flow cytometric measurement. Astrocyte-derived EVs were identified using flow cytometry with markers for aquaporin 4 (AQP-4) and glial fibrillary acidic protein (GFAP). Levels of the S100B protein were measured using a commercial ELISA. Disease activity was assessed using the Juvenile Arthritis Disease Activity Score (JADAS27, 0-57), and pain levels were measured using a visual analogue scale (VAS, 0-10 cm).

RESULTS

Our analyses revealed a significantly higher concentration of astrocyte-derived EVs in the plasma of children with JIA compared with healthy controls. Furthermore, children with JADAS27 scores of 1 or higher exhibited notably higher levels of these EVs. The S100B protein was detectable exclusively in the JIA group.

CONCLUSION

The elevated levels of astrocyte-derived EVs and the presence of S100B in children with JIA provide evidence of BBB disruption and CNS involvement, particularly in those with higher disease activity. These findings underscore the importance of considering CNS health in the comprehensive management of JIA. Further research is required to elucidate the mechanisms behind CNS engagement in JIA and to develop treatments that address both joint and CNS manifestations of the disease.

Effects of a home-based exercise combined yoga and resistance training in enthesitis-related arthritis in China: study protocol for a randomised controlled trial

INTRODUCTION

Enthesitis-related arthritis (ERA) is a category of juvenile idiopathic arthritis (JIA). The complications of JIA include pain, muscle weakness, limited movement and worsening quality of life. Yoga is an effective exercise therapy for rheumatoid arthritis and may have similar benefits for JIA. Considering the limitation of yoga for strengthening muscles, combined yoga and resistance training (CYRT) may compensate for the shortcomings and provide more benefits for JIA patients. Despite this, there is currently a lack of studies investigating the effectiveness of CYRT for JIA patients. Due to the inaccessibility of traditional exercise therapy, home-based exercise is needed. The study aims to assess the effectiveness of home-based CYRT on JIA.

METHODS AND ANALYSIS

This is a 12-week randomised single-blind controlled trial study. 60 patients with ERA will be randomised into two groups: the home-based exercise group (HBE) and the health education (HE) group. The HBE group (n=30) will perform the CYRT programme 3 times a week at home for 12 weeks and receive HE. The HE group (n=30) will only receive HE. The outcomes include primary outcome (pain levels) and secondary outcomes (lower limb muscle strength, motion range of joint, aerobic fitness, function ability, fatigue levels, mental health, quality of life and blood biomarkers). The assessments will be conducted at baseline, postintervention (12 weeks) and follow-up (24 weeks). Data will be analysed by intention to treat.

ETHICS AND DISSEMINATION

This study has been approved by the Ethics Committee of Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine in December 2023 (approval no. XHEC-C-2023-059-3). This study will require informed consent from all subjects and guardians of children under 18 years of age. The findings will be published in a peer-reviewed journal and international conferences.

TRIAL REGISTRATION NUMBER

ChiCTR2300073446.

GH therapy in children with juvenile idiopathic arthritis: a four-decade review

Chronic inflammatory conditions, such as juvenile idiopathic arthritis, are associated with growth failure. Growth failure appears to be correlated with both the effects of inflammation and negative effects of glucocorticoids (used as therapeutic option) on the growth hormone axis and locally on the growth plate and bone metabolism. In the last decade, the introduction of biologics has changed the disease course regarding consequences and outcomes. Anyway in some cases, treatment with biologics has failed in restoring normal growth in patients with juvenile idiopathic arthritis; in contrast, several studies have reported improved height velocity and growth rate in patients with juvenile idiopathic arthritis treated with growth hormone. This study aimed to evaluate the impact of growth hormone treatment on the growth and pubertal development in juvenile idiopathic arthritis patients through a narrative review of the literature over the last four decades.

The benefits of physical therapy in juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease in children and an important cause of short-term and long-term disability. Recommended physiotherapy activity programs are essential for controlling JIA associated complications such as stiffness, deformity, muscle contractures, and cramps. It is uncertain if physiotherapy (PT) can significantly enhance prognosis and quality of life (QOL). In this review we focused on the specific effects of various PT on JIA manifestations. To conduct a literature review, the databases PubMed, Scopus, and DOAJ (last access in June 2023) were searched. The PubMed search returned a total of 952 articles, Scopus returned 108, and DOAJ returned no results. After screening, the final list included 18 papers on PT treatment for JIA patients. In children with JIA, targeted PT exercise may have the ability to improve strength, posture, aerobic conditioning, gait, functional mobility, and reduce pain.

Therapeutic potential of Coptis chinensis for arthritis with underlying mechanisms

Arthritis is a common degenerative disease of joints, which has become a public health problem affecting human health, but its pathogenesis is complex and cannot be eradicated. Coptis chinensis (CC) has a variety of active ingredients, is a natural antibacterial and anti-inflammatory drug. In which, berberine is its main effective ingredient, and has good therapeutic effects on rheumatoid arthritis (RA), osteoarthritis (OA), gouty arthritis (GA). RA, OA and GA are the three most common types of arthritis, but the relevant pathogenesis is not clear. Therefore, molecular mechanism and prevention and treatment of arthritis are the key issues to be paid attention to in clinical practice. In general, berberine, palmatine, coptisine, jatrorrhizine, magnoflorine and jatrorrhizine hydrochloride in CC play the role in treating arthritis by regulating Wnt1/β-catenin and PI3K/AKT/mTOR signaling pathways. In this review, active ingredients, targets and mechanism of CC in the treatment of arthritis were expounded, and we have further explained the potential role of AHR, CAV1, CRP, CXCL2, IRF1, SPP1, and IL-17 signaling pathway in the treatment of arthritis, and to provide a new idea for the clinical treatment of arthritis by CC.

MicroRNA-27a-3p enhances the inflammatory phenotype of Juvenile Idiopathic Arthritis fibroblast-like synoviocytes

BACKGROUND

Juvenile Idiopathic Arthritis (JIA) is the most prevalent chronic pediatric rheumatic disorder. In joints of JIA patients, aggressive phenotypic changes in fibroblast-like synoviocytes (FLS) of the synovial lining play a key role in inflammation. MicroRNAs are dysregulated in rheumatoid arthritis and JIA, including miR-27a-3p. However, it is not understood if miR-27a-3p, enriched in JIA synovial fluid (SF) and leukocytes, alters FLS function.

METHODS

Primary JIA FLS cells were transfected with a miR-27a-3p mimic or a negative control microRNA (miR-NC) and stimulated with pooled JIA SF or inflammatory cytokines. Viability and apoptosis were analyzed by flow cytometry. Proliferation was evaluated using a ³H-thymidine incorporation assay. Cytokine production was assessed by qPCR and ELISA. Expression of TGF-β pathway genes was determined using a qPCR array.

RESULTS

MiR-27a-3p was constitutively expressed in FLS. Overexpression of miR-27a-3p caused increased interleukin-8 secretion in resting FLS, and interleukin-6 was elevated in SF-activated FLS compared to miR-NC. Furthermore, stimulation with pro-inflammatory cytokines augmented FLS proliferation in miR-27a-3p-transfected FLS relative to miR-NC. Expression of multiple TGF-β pathway genes was modulated by overexpression of miR-27a-3p.

CONCLUSIONS

MiR-27a-3p significantly contributes to FLS proliferation and cytokine production, making it a potential candidate for epigenetic therapy that targets FLS in arthritis.