A new look at rheumatology in China--opportunities and challenges

Integrating serum pharmacochemistry, network pharmacology, metabolomics and 16S rRNA sequencing to explore the mechanism of total flavonoids from Flemingia philippinensis in treating collagen induced arthritis rats

BACKGROUD

Rheumatoid arthritis (RA) is a prevalent chronic autoimmune disease characterized by symmetric polyarthritis, resulting in pain and swelling in the synovial joints. Flemingia philippinensis, a traditional Chinese medicine, has been shown to be an effective treatment approach for anti-rheumatoid arthritis (RA), which still needs further research in its active ingredient and regulatory mechanisms.

PURPOSE

This study aimed at investigate the pharmacodynamic basis and intricate mechanism of action of Flemingia philippinensis (FPTF) in the treatment of RA based on integrated omics technologies.

METHODS

UPLC-Q-Orbitrap HRMS was first established to identify the active components of FPTF in blood and network pharmacology was then used to predict the key therapeutic targets and corresponding pathways of FPTF in treatment of RA. To substantiate the pharmacodynamic effects, a collagen-induced arthritis (CIA) animal model was employed to observe the anti-RA effects of FPTF through a series of indicators, including rat body weight, arthritis scoring, paw swelling, histopathological analysis of synovial tissue, and serum inflammatory factors. Subsequently, the potential mechanisms underlying the anti-RA efficacy of FPTF was elucidated by integrating metabolomics analysis with 16S rRNA gene sequencing. Specifically, the RT-qPCR experiment was further conducted to validate the pathways predicted by serum pharmacochemistry, network pharmacology, metabolomics and 16S rRNA gene sequencing.

RESULTS

A total of 10 compounds derived from FPTF were identified by serum sample analysis. Utilizing network pharmacology, we identified 117 common targets for FPTF in the treatment of RA. Notably, KEGG analysis highlighted the PI3K/AKT signaling pathway and the IL17 signaling pathway as key pathways associated with the anti-RA effects of FPTF. Pharmacodynamic studies showed that FPTF can significantly alleviate CIA-induced arthritis. Compared with the CIA model group, FPTF treatment significantly improved the expression of mRNA in the PI3K/AKT and IL-17 signaling pathways. Further investigation unveiled a total of 28 differential metabolites in serum samples, among which 21 metabolites were observed to be reversed following FPTF administration. Metabolomic profiling revealed pronounced perturbations in amino acid metabolism, fatty acid metabolism, and glycerophospholipid metabolism pathways in CIA rats, which were partially rectified by FPTF treatment. Additionally, 16S rRNA gene sequencing analysis indicated that FPTF could restore the gut microbiota balance disrupted by RA. RT-qPCR further confirmed that FPTF can modulate key enzymes in metabolic pathway analysis and gut microbiota metabolic pathways.

CONCLUSION

This study pioneeringly elucidates the potential pharmacodynamic material basis of FPTF for treatment of RA, detailing the regulated metabolic pathways and key gut microbiota genera involved. The findings provide a comprehensive understanding of mechanisms underlying the effects of FPTF in RA treatment.

Dual-driven selenium Janus single-atom nanomotors for autonomous regulating mitochondrial oxygen imbalance to catalytic therapy of rheumatoid arthritis

O2 deficiency and excessive reactive oxygen and nitrogen species (RONS) in macrophage mitochondria is a key factor causing oxygen imbalance in rheumatoid arthritis microenvironment (RAM). Although nanocatalytic therapy that simultaneously produce O2 and eliminate RONS offer a novel strategy for RA therapy, the therapeutic efficacy of nanozymes is limited by the lack of autonomous targeting into mitochondria. Herein, we constructed a Janus-structured nanomotor (Pd@MSe) with autonomous targeting ability by embedding Pd single-atom nanozymes into mesoporous selenium (MSe) nanozymes, and obtained a composite nanomotor (Pd@MSe-TPP) with dual-driven forces by modifying with triphenylphosphine (TPP) in MSe hemisphere. In RAM, Pd@MSe-TPP nanomotor achieved autonomously target into macrophages mitochondria with the driven of generation O2 and TPP targeting effect, moreover under the single-atom effect of the Pd nanozymes enhanced electronic transfer between nanozymes, which significantly boosted GPx catalytic activity further effectively enhanced the diffusion of Pd@MSe-TPP nanomotor, thus quickly resorted the oxygen balance. Additionally, while regulating oxygen imbalance, Pd@MSe-TPP nanomotor enable rapidly blocked the inflammatory cascade, restored mitochondrial function and alleviated inflammation, further prevented cartilage degradation and effectively inhibited RA progression. Therefore, the exquisitely designed nanoplatform to regulation arthritic microenvironment provides a new direction for the RA therapy and the clinical translation of nanomedicine.

CD305 participates in abnormal activation of memory CD4+ T cells in patients with RA and attenuates collagen-induced arthritis

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease that mainly affects the joints. Studies have shown that memory CD4+ T cells play an important role in the pathogenesis of RA. This study investigated the expression and function of CD305 on human memory CD4+ T cells and the effects of CD305 activating antibody on collagen-induced arthritis. The results showed that CD305 expression was significantly decreased on circulating memory CD4+ T cells from patients with RA and its mean fluorescence intensity (MFI) was negatively correlated with DAS28. Moreover, CD305 inhibited the activation of memory CD4+ T cells by down-regulating CD69 and CD25 and the production of IFN-γ, IL-4, and IL-17A induced by anti-CD3/CD28 antibodies. In addition, activation of CD305 inhibited the severity of disease in collagen-induced arthritis. In summary, CD305 reduction may mediate the excessive activation of memory CD4+ T cells and participate in the development of RA. It can be used as a predictive marker of disease activity and has potential medicinal value in the treatment of RA.

Nanomedicine targeted anti-inflammatory therapy to deal with the 'crux' of rheumatoid arthritis

Rheumatoid arthritis is a chronic and complex autoimmune disease that is marked by an inflammatory response, synovial hyperplasia, vascularisation, fascial formation, cartilage and bone destruction, which can lead to joint deformity and even loss of function, ultimately affecting a person's health and quality of life. Although the pathogenesis of RA is unclear, growing evidence suggests that inflammation-associated cells infiltrate joints, causing tissue damage, inflammation and pain. This disruption in the balance between host tolerance and immune homeostasis the progression of RA. Existing drug therapy and surgical treatments for RA are unable to completely cure the disease or reverse its accelerated progression. Therefore, the design and development of an appropriate and effective drug delivery system will substantially improve the therapeutic effect. In this review, by describing the inflammatory microenvironment of rheumatoid arthritis and the associated inflammatory cells, the progress of targeting strategies and applications of nanotechnology in the disease is summarised, which will be helpful in providing new ideas for the subsequent treatment of rheumatoid arthritis.

Hypercoagulability in Rheumatoid Arthritis: A Bibliometric Analysis and Retrospective Data Mining Study

BACKGROUND

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic systemic inflammation, leading to joint deformities and functional loss. RA progression is accompanied by abnormalities in the coagulation-fibrinolysis system, clinically manifested as a hypercoagulable state. However, there are currently no bibliometrics or visualization analysis in this field.

OBJECTIVE

The present study aims to reveal the knowledge structure, research status, and research trends related to hypercoagulability in RA through bibliometric analysis and to evaluate the utility of inflammatory and coagulation markers in RA disease activity through retrospective data mining.

METHODS

English articles and reviews on RA hypercoagulability published from 2010 to 2023 were extracted from the Web of Science Core Collection (WoSCC) database on March 1, 2023. VOSviewer and CiteSpace software were used for knowledge mapping analysis of the included papers in terms of countries/regions, institutions, journals, authors, keywords, research hotspots, and frontiers. A retrospective analysis was conducted on the general information on RA patients. The demographic and clinical indicators of all participants were collected to determine the correlation of inflammatory and coagulation markers with the Chinese patient-reported activity index for rheumatoid arthritis (CPRI-RA).

RESULTS

A total of 957 papers were retrieved. The United States was the most productive country in this field and had the highest h-index, and the most prolific institution was the Karolinska Institute. The Annals of the Rheumatic Diseases was the journal with the most publications, and KLARESKOG L. was the most productive author. From keyword analysis, it could be seen that "inflammation", "activation", "disease-activity", and "risk" had long been the focuses of RA hypercoagulability research. "Criteria", "validation", "coagulation", "target", and "anemia" were the latest popular keywords in the past 5 years. Retrospective data mining revealed that the levels of inflammation (RF, ESR, and CRP) and coagulation (PLT and DD) were significantly increased in RA patients. FBG, CRP, and ESR were significantly correlated with CPRI-RA. Additionally, ESR, CRP, and FBG were identified as independent risk factors for CPRI-RA.

CONCLUSION

The mechanism and application of hypercoagulability in RA have been research hotspots in recent years. Inflammation and coagulation markers are independent risk factors for CPRI-RA.

Comprehensive multi-omics analysis reveals the core role of glycerophospholipid metabolism in rheumatoid arthritis development

OBJECTIVES

Rheumatoid arthritis (RA) is a chronic autoimmune disease with complex causes and recurrent attacks that can easily develop into chronic arthritis and eventually lead to joint deformity. Our study aims to elucidate potential mechanism among control, new-onset RA (NORA) and chronic RA (CRA) with multi-omics analysis.

METHODS

A total of 113 RA patients and 75 controls were included in our study. Plasma and stool samples were obtained for 16S rRNA sequencing, internally transcribed spacer (ITS) sequencing and metabolomics analysis. And PBMCs were obtained for RNA sequencing. We used three models, logistic regression, least absolute shrinkage and selection operator (LASSO), and random forest, respectively, to distinguish NORA from CRA, and finally we validated model performance using an external cohort of 26 subjects.

RESULTS

Our results demonstrated intestinal flora disturbance in RA development, with significantly increased abundance of Escherichia-Shigella and Proteobacteria in NORA. We also found that the diversity was significantly reduced in CRA compared to NORA through fungi analysis. Moreover, we identified 29 differential metabolites between NORA and CRA. Pathway enrichment analysis revealed significant dysregulation of glycerophospholipid metabolism and phenylalanine metabolism pathways in RA patients. Next, we identified 40 differentially expressed genes between NORA and CRA, which acetylcholinesterase (ACHE) was the core gene and significantly enriched in glycerophospholipid metabolism pathway. Correlation analysis showed a strong negatively correlation between glycerophosphocholine and inflammatory characteristics. Additionally, we applied three approaches to develop disease classifier models that were based on plasma metabolites and gut microbiota, which effectively distinguished between new-onset and chronic RA patients in both discovery cohort and external validation cohort.

CONCLUSIONS

These findings revealed that glycerophospholipid metabolism plays a crucial role in the development and progression of RA, providing new ideas for early clinical diagnosis and optimizing treatment strategies.

LCK, FOXC1 and hsa-miR-146a-5p as potential immune effector molecules associated with rheumatoid arthritis

Rheumatoid arthritis (RA) is a type of systemic immune disease characterized by chronic inflammatory disease of the joints. However, the aetiology and underlying molecular events of RA are unclear. Here, we applied bioinformatics analysis to identify potential immune effector molecules involved in RA. The three microarray datasets were downloaded from the Gene Expression Omnibus (GEO) database. We used the R software screen 115 overlapping differentially expressed genes (DEGs). Subsequently, we constructed a protein-protein interaction (PPI) network encoded by these DEGs and identified 10 genes closely associated with RA - LCK, GZMA, GZMB, CD2, LAG3, IL-15, TNFRSF4, CD247, CCR5 and CCR7. Furthermore, in the miRNA-hub gene networks, we screened out hsa-miR-146a-5p, which is the miRNA controlling the largest number of hub genes. Finally, we found some transcription factors that closely interact with hub genes, such as FOXC1, GATA2, YY1, RUNX2, SREBF1, CEBPB and NFIC. This study successfully predicted that LCK, FOXC1 and hsa-miR-146a-5p can be used as potential immune effector molecules of RA. Our study may have potential implications for future prediction of disease progression in patients with symptomatic RA, and has important significance for the pathogenesis and targeted therapy of RA.

Hypoxia Inhibits Osteogenesis and Promotes Adipogenesis of Fibroblast-like Synoviocytes via Upregulation of Leptin in Patients with Rheumatoid Arthritis

Hypoxia is associated with the pathogenesis of rheumatoid arthritis (RA). RA fibroblast-like synoviocytes (FLSs) are able to differentiate into osteoblasts and adipocytes. In this study, we aimed to investigate the role of hypoxia in the osteogenesis or adipogenesis of RA-FLSs. Bioinformatics analysis was performed to profile gene expression in the datasets of GSE21959, GSE32006, and GSE55875, and flow cytometry was performed for FLS characterization, while Alizarin Redand Oil Red O staining for osteogenic or adipogenic differentiation of FLSs, respectively. RNA interference leptin knockdown was used to determine the role of leptin in the osteogenesis and adipogenesis of RA-FLSs, and the expression of osteogenic and adipogenic markers was quantified by RT-qPCR and Western blotting. FLSs exhibited a mesenchymal stem cell (MSC)-like phenotype and we observed a limited self-renewal capacity in RA-FLSs compared to that in MSCs, but it was still greater than osteoarthritis (OA)-FLSs. Hypoxia did not change the RA-FLS MSC-like phenotype but inhibited the osteogenic differentiation and promoted the adipogenic differentiation of RA-FLSs. From the bioinformatics analysis ofGSE21959, GSE32006, and GSE55875 datasets, we found leptin, the only perturbed hypoxia-mediated upregulated gene across the three profiled datasets. Leptin knockdown in RA-FLSs reversed the hypoxia-mediated reduction of osteogenesis and hypoxia-mediated enhancement of adipogenesis by elevated expression of osteogenic markers and reduced expression of adipogenic markers, respectively. Therefore, hypoxia-leptin regulation of the osteogenic and adipogenic differentiation of RA-FLSs advances our understanding of RA pathogenesis, meanwhile also provides opportunities for future therapeutic intervention of RA.

Inflammatory Cytokine-Neutralizing Antibody Treatment Prevented Increases in Follicular Helper T Cells and Follicular Regulatory T Cells in a Mouse Model of Arthritis

Background

Follicular T helper (TFH) and follicular regulatory T (TFR) cells play important roles in humoral immunity. Nevertheless, their significance in rheumatoid arthritis (RA) pathogenesis has not been fully elucidated. As an important treatment strategy, the effect of inflammatory factor-neutralizing antibodies on TFH and TFR in RA remains unclear.

Methods

We used the collagen-induced arthritis (CIA) mouse model to illustrate the quantity and functional changes in TFH and TFR cells. The changes of plasmablast, TFH and TFR cells in the spleen and peripheral blood of CIA mice were analyzed by flow cytometry. The levels of TFH and TFR and their functional subsets in the spleen after anti-inflammatory antibody treatment were analyzed and compared. The functional changes of TFH and TFR in CIA mice before and after treatment were detected by in vitro culture experiments.

Results

Plasmablast levels were increased in CIA spleen and peripheral blood and both TFH and TFR cell levels were upregulated. TFH and TFR cells were decreased significantly after the anti-inflammatory antibody treatment. TIGIT⁺ and TIGIT⁺CD226⁻ TFH cells in CIA mouse spleen were elevated and PD-1 and ICOS expression on spleen TFH and TFR cells was increased. Both the ability of TFH cells to secrete IL-21 and aid B cells and the ability of TFR cells to secrete IL-10 and inhibit TFH cells were enhanced in the CIA mice. After antibody treatment, the cell subsets and functions were recovered.

Conclusion

Germinal center TFH and TFR cells were increased and their functions were enhanced. With inflammatory factor-neutralizing antibody treatment, TFH and TFR subsets and their functions returned to normal. These findings provide important information on the dynamics of humoral immune-related cell subsets in RA and the effects of treatment on them.

Lactate metabolism in rheumatoid arthritis: Pathogenic mechanisms and therapeutic intervention with natural compounds

BACKGROUND

Rheumatoid arthritis (RA) is a common chronic and systemic autoimmune disease characterized by persistent inflammation and hyperplasia of the synovial membrane, the degradation of cartilage, and the erosion of bones in diarthrodial joints. The inflamed joints of patients with RA have been recognized to be a site of hypoxic microenvironment which results in an imbalance of lactate metabolism and the accumulation of lactate. Lactate is no longer considered solely a metabolic waste product of glycolysis, but also a combustion aid in the progression of RA from the early stages of inflammation to the late stages of bone destruction.

PURPOSE

To review the pathogenic mechanisms of lactate metabolism in RA and investigate the potential of natural compounds for treating RA linked to the regulation of imbalance in lactate metabolism.

METHODS

Research advances in our understanding of lactate metabolism in the pathogenesis of RA and novel pharmacological approaches of natural compounds by targeting lactate metabolic signaling were comprehensively reviewed and deeply discussed.

RESULTS

Lactate produced by RA synovial fibroblasts (RASFs) acts on targeted cells such as T cells, macrophages, dendritic cells and osteoclasts, and affects their differentiation, activation and function to accelerate the development of RA. Many natural compounds show therapeutic potential for RA by regulating glycolytic rate-limiting enzymes to limit lactate production, and affecting monocarboxylate transporter and acetyl-CoA carboxylase to inhibit lactate transport and conversion.

CONCLUSION

Regulation of imbalance in lactate metabolism offers novel therapeutic approaches for RA, and natural compounds capable of targeting lactate metabolic signaling constitute potential candidates for development of drugs RA.

SM03, an anti-human CD22 monoclonal antibody, for active rheumatoid arthritis: a phase II randomized, double-blind, placebo-controlled study

OBJECTIVE

SM03, a novel chimeric monoclonal antibody specific to B cell-restricted antigen CD22, has been developed to treat rheumatoid arthritis (RA) and other B cell-related diseases. This 24-week Phase II randomized, double-blind, multi-dose, placebo-controlled study aimed to evaluate the efficacy and safety of SM03 in moderately-to-severely active RA patients in China.

METHODS

One hundred fifty-six patients on background methotrexate were randomized in a 1:1:1 ratio to receive a cumulative dose of 3600 mg (high dose, 600 mg * 6 infusions at weeks 0, 2, 4, 12, 14, and 16) or 2400 mg SM03 (low dose, 600 mg * 4 infusions at weeks 0, 2, 12, and 14), or the placebo. The primary outcome was the 24-week American College of Rheumatology 20% improvement criteria (ACR20) response rate. Safety was also assessed.

RESULTS

The 24-week ACR20 response rate was significantly higher with high (65.3%, p= 0.002) and low-dose SM03 (56.9%, p= 0.024) than placebo (34.0%), but comparable between the high and low dose group. The rate of adverse events was not statistically different among the high dose group (35.3%), the low dose group (51.9%) and the placebo group (34.6%). Thirteen (12.6%) patients receiving SM03 reported treatment-emergent infections, including 3.9% patients in the high-dose group. No patients reported severe treatment-emergent infections or malignancies.

CONCLUSIONS

In active RA Chinese patients receiving background methotrexate, SM03 at a cumulative dose of both 2400 mg and 3600 mg is efficacious and well-tolerated throughout the 24 weeks of treatment. Moreover, SM03 has demonstrated a good safety profile.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, https://clinicaltrials.gov, NCT04192617.

Circulating CD4+ FoxP3- CXCR5- CXCR3+ PD-1hi cells are elevated in active rheumatoid arthritis and reflect the severity of the disease

OBJECTIVE

To examine the expression and clinical significance of circulating CD4⁺  FoxP3^-  CXCR5^-  CXCR3⁺  PD-1^hi cells in rheumatoid arthritis (RA).

METHODS

CD4⁺  FoxP3^-  CXCR5^-  CXCR3⁺  PD-1^hi cells in peripheral blood of 35 patients with active RA, 17 with RA in stable remission, and 24 healthy controls were analyzed by flow cytometry. Serum IgG and circulating plasmablast percentages were measured and correlations with CD4⁺  FoxP3^-  CXCR5^-  CXCR3⁺  PD-1^hi cells were systematically analyzed. Disease Activity Scale 28 (DAS28) scores were also calculated and correlation analysis with CD4⁺  FoxP3^-  CXCR5^-  CXCR3⁺  PD-1^hi cells was conducted. The levels of CD4⁺  FoxP3^-  CXCR5^-  CXCR3⁺  PD-1^hi cells were compared before and after disease-modifying anti-rheumatic drug treatment. Cytokine levels in plasma and cytokine secretion in CD4 cells were measured and their correlations with CD4⁺  FoxP3^-  CXCR5^-  CXCR3⁺  PD-1^hi cells were further analyzed.

RESULTS

The levels of CD4⁺  FoxP3^-  CXCR5^-  CXCR3⁺  PD-1^hi cells in the peripheral blood of patients with active RA were significantly increased compared with healthy controls. CD4⁺  FoxP3^-  CXCR5^-  CXCR3⁺  PD-1^hi cells in patients with active RA were positively correlated with serum IgG and DAS28 scores. CD4⁺  FoxP3^-  CXCR5^-  CXCR3⁺  PD-1^hi cells were significantly decreased in patients after treatment. Plasma interleukin-10 concentrations and interleukin-10-positive CD4 cell percentages were significantly positively correlated with CD4⁺  FoxP3^-  CXCR5^-  CXCR3⁺  PD-1^hi cell levels.

CONCLUSION

Circulating CD4⁺  FoxP3^-  CXCR5^-  CXCR3⁺  PD-1^hi cells in patients with active RA are increased and could reflect the severity of the disease, which may play a potential role in the pathogenesis of RA.

Nanomedicines for the treatment of rheumatoid arthritis: State of art and potential therapeutic strategies

Increasing understanding of the pathogenesis of rheumatoid arthritis (RA) has remarkably promoted the development of effective therapeutic regimens of RA. Nevertheless, the inadequate response to current therapies in a proportion of patients, the systemic toxicity accompanied by long-term administration or distribution in non-targeted sites and the comprised efficacy caused by undesirable bioavailability, are still unsettled problems lying across the full remission of RA. So far, these existing limitations have inspired comprehensive academic researches on nanomedicines for RA treatment. A variety of versatile nanocarriers with controllable physicochemical properties, tailorable drug release pattern or active targeting ability were fabricated to enhance the drug delivery efficiency in RA treatment. This review aims to provide an up-to-date progress regarding to RA treatment using nanomedicines in the last 5 years and concisely discuss the potential application of several newly emerged therapeutic strategies such as inducing the antigen-specific tolerance, pro-resolving therapy or regulating the immunometabolism for RA treatments.

Cost-Effectiveness of Baricitinib for Patients with Moderate-to-Severe Rheumatoid Arthritis After Methotrexate Failed in China

INTRODUCTION

A phase 3 (RA-BEAM study) clinical trial reported that baricitinib (BCT) + methotrexate (MTX) had clinical improvement compared with adalimumab (ADA) + MTX as a first-line strategy in patients with rheumatoid arthritis (RA) who had inadequate responses to MTX monotherapy. However, from the perspective of the Chinese healthcare system, the cost-effectiveness of introducing BCT into current treatment for patients with RA unresponsive to MTX remains unclear.

METHODS

A patient-level microsimulation model was used to extrapolate the lifetime incremental cost per quality-adjusted life-year (QALY) and other outcomes. This study compared treatment sequences with or without first-line BCT with current treatment sequences, including adalimumab, etanercept, tocilizumab, and palliative care. Effectiveness and physical function were assessed using the American College of Rheumatology (ACR) 20/50/70 response and Health Assessment Questionnaire (HAQ). The input parameters of the model, comprising patient characteristics (sex and age) and treatment efficacy (ACR responses and HAQ score), were derived from a phase III clinical trial and network meta-analysis. The total cost estimation included direct costs and indirect costs. Probabilistic and univariate sensitivity analyses were performed, as were a series of scenario analyses.

RESULTS

The lifetime analysis revealed that adding BCT as a first-line treatment resulted in a QALY gain of 2.66 years; this gain would cost an incremental $26,662, leading to an incremental cost-effectiveness ratio of $10,036/QALY per patient compared with the current treatment sequence. Sensitivity and scenario analyses showed the results to be robust.

CONCLUSIONS

From a Chinese payer perspective, the introduction of BCT into the current treatment sequence is projected to be a cost-effective option as first-, second-, third-, and fourth-line treatment for patients with moderate-to-severe RA.

Polysaccharides and glycosides from Aralia echinocaulis protect rats from arthritis by modulating the gut microbiota composition

ETHNOPHARMACOLOGICAL RELEVANCE

Aralia echinocaulis has been used in traditional medicines in China and exhibits good effects on rheumatoid arthritis (RA).

AIM OF THE STUDY

Aralia echinocaulis is rich in polysaccharides and glycosides. This study aims to explore the effect of total polysaccharide and glycoside (TPG) from A. echinocaulis on an RA rat model and the role of alterations in gut microbes mediated by TPG.

MATERIALS AND METHODS

In this study, a collagen-induced arthritis (CIA) rat model was constructed and used to evaluate the effects of TPG in vivo. 16S rRNA sequencing was used to detect the changes in the gut microbiota. A cooccurrence analysis was conducted by calculating Spearman's rank correlations. Microbial functions were predicted using PICRUSt with the KEGG and COG databases.

RESULTS

The results showed that TPG from A. echinocaulis could inhibit arthritis, reduce serum IL-1β and TNF-α levels, and improve synovial pathology in the RA rat model but failed to produce the same results in a pseudoaseptic RA rat model. 16S rRNA sequencing verified that TPG could modulate the gut microbiota community structure of RA rats. The cooccurrence analysis found 19 out of the 50 most abundant genera in a cooccurrence network, of which 16 showed a positive correlation and 3 showed a negative correlation. KEGG pathway and COG function analyses found that TPG-induced alterations in the gut microbiota might be correlated with the circulatory system, excretory system, metabolic diseases, signaling molecules and interactions, coenzyme transport and metabolism, and nucleotide transport and metabolism.

CONCLUSIONS

TPG from A. echinocaulis had significant effects on the RA rat model, which are related to the modulation of the gut microbiota. These results are useful to better understanding the mechanisms of TPG in RA.

Muscle wasting, a neglected complication associated with physical dysfunction in elderly patients with rheumatoid arthritis: a cross-sectional observational study

Objective: Little is known about muscle wasting in elderly patients with rheumatoid arthritis (RA). We examined muscle characteristics and their clinical significance in this group.Method: Consecutive RA patients were recruited and clinical data were collected. Muscle mass and distribution were assessed using bioelectric impedance analysis. Myopenia was defined as an appendicular skeletal muscle mass index (ASMI) ≤ 7.0 kg/m² (men) and ≤ 5.7 kg/m² (women).Results: Among the 643 RA patients recruited, 165 (25.7%) were elderly patients (age ≥ 60 years) with a mean age of 65.1 ± 4.5 years. Compared with young patients (age < 60 years), elderly RA patients had significantly higher Disease Activity Score based on 28-joint count-C-reactive protein (DAS28-CRP) (median 3.4 vs 3.2), Health Assessment Questionnaire Disability Index (HAQ-DI) (0.38 vs 0.13), and modified total Sharp score (mTSS) (16 vs 9), and a higher proportion of myopenia (54.5% vs 41.4%; all p < 0.01). Elderly RA patients with myopenia (n = 90, 14.0%) had significantly higher DAS28-CRP (3.6 vs 3.0), HAQ-DI (0.50 vs 0.12), and mTSS (21 vs 7) than young RA patients without myopenia (n = 280, 43.5%; all p < 0.0083). Multivariate logistic and linear regression analyses showed that myopenia, high HAQ-DI, active smoking, hypertension, diabetes, and coronary atherosclerotic heart disease were the main relevant characteristics of elderly RA patients. Age positively correlated with HAQ-DI, and ASMI negatively correlated with HAQ-DI (both p < 0.01). Further mediation analysis showed that ASMI partially mediated the association between age and HAQ-DI.Conclusion: Our data reveal that half of elderly RA patients manifest myopenia which aggravates physical dysfunction as a mediator of age. Myopenia, a neglected complication in elderly RA patients, should be recognized and further investigated.

Health Disparities in Rheumatic Diseases: Understanding Global Challenges in Africa, Europe, Latin America, and Asia and Proposing Strategies for Improvement

Rheumatic diseases reach across continents with some similarities as well as unique challenges. The intersection between genetic factors, environmental exposures and socioeconomic factors, as well as challenges, with delays in access to subspecialty care and medications, manifest in different ways. By understanding both the challenges and successes in different countries, while also recognizing the significant diversity both within and across continents, unified strategies to improve rheumatic disease outcomes and decrease disparities among the most vulnerable groups can be developed and disseminated.

Myeloid-derived suppressor cells shift Th17/Treg ratio and promote systemic lupus erythematosus progression through arginase-1/miR-322-5p/TGF-β pathway

Immune cells play important roles in systemic lupus erythematosus (SLE). We previously found that myeloid-derived suppressor cell (MDSC)-derived arginase-1 (Arg-1) promoted Th17 cell differentiation in SLE. In the present study, we performed RNA-chip to identify the microRNA regulation network between MDSCs and Th17 cells. miR-542-5p in humans, as the homologous gene of miR-322-5p in mice was significantly up-regulated in the Th17+MDSC group compared with Th17 cells cultured alone and down-regulated in the Th17+MDSC+Arg-1 inhibitor group compared with the Th17+MDSC group. We further evaluated the miR-322-5p and Th17/Treg balance in mice and found that the proportions of both Th17 cells and Tregs were elevated and that miR-322-5p overexpression activated the transforming growth factor-β pathway. Moreover, although miR-322-5p expression was higher in SLE mice, it decreased after treatment with an Arg-1 inhibitor. The proportion of Th17 cells and Th17/Treg ratio correlated with miR-322-5p levels. In conclusion, MDSC-derived Arg-1 and mmu-miR-322-5p not only promote Th17 cell and Treg differentiation, but also shift the Th17/Treg ratio in SLE. The Arg-1/miR-322-5p axis may serve as a novel treatment target for SLE.

Rheumatology in Ukraine

Rheumatology in Ukraine is based on established research and clinical infrastructure that enable the integration with regional and global societies. This article overviews current state of Ukrainian rheumatology, important steps toward expanding clinical settings, and opportunities for strengthening cooperation of local rheumatologists and patients with rheumatic diseases with related international societies. The main achievements and some challenges encountered by the Association of Rheumatologists of Ukraine are outlined. The Association supports continuing medical education of local specialists and explores options for advancing research and publishing in rheumatology. One of the main challenges still remains the creation of registries of patients with rheumatic diseases and expansion of activities of public societies with interest in combating rheumatic diseases. The issue of inadequate access to immunobiological therapies is also highlighted.

Iguratimod Inhibits the Aggressiveness of Rheumatoid Fibroblast-Like Synoviocytes

Objective

Iguratimod, a novel disease-modifying anti-rheumatic drug for the treatment of rheumatoid arthritis, has been approved in China and Japan. Here, we aimed to find whether iguratimod can inhibit the aggressive behavior and promote apoptosis of rheumatoid fibroblast-like synoviocytes (RA-FLSs).

Methods

The proliferation of RA-FLSs was assessed by 5-ethynyl-2′-deoxyuridine test and Cell Counting Kit-8. Migration and invasion were determined by the wound test and a transwell assay. Apoptosis was tested by flow cytometry. The mRNA expression of matrix metalloproteinases (MMPs) and proinflammatory cytokines in RA-FLSs were measured by quantitative PCR and ELISA. To gain insight into the molecular signaling mechanisms, we determined the effect of iguratimod on the activation of mitogen-activated protein kinases (MAPK) signaling pathways by the cellular thermal shift assay (CETSA) and western blot.

Results

Iguratimod treatment significantly reduced the proliferation, migration, and invasive capacities of RA-FLSs in a dose-dependent manner in vitro. MMP-1, MMP-3, MMP-9, Interleukin-6 (IL-6), and monocyte chemoattractant protein-1 mRNA and protein levels were all decreased after treatment with iguratimod. Furthermore, tumor necrosis factor-alpha- (TNF-α-) induced expression of phosphorylated c-Jun N-terminal kinases (JNK) and P38 MAPK were inhibited by iguratimod. Additionally, iguratimod promoted the apoptosis of RA-FLSs. Most importantly, iguratimod was shown to directly interact with JNK and P38 protein by CETSA assay. Moreover, activating transcription factor 2 (ATF-2), a substrate of both JNK and P38, was suppressed by iguratimod.

Conclusions

Our findings suggested that the therapeutic effects of iguratimod on RA might be, in part, due to targeting the aggressive behavior and apoptosis of RA-FLSs.

Healthcare disparities in rheumatology: the role of education at a global level

All fields of medicine are victim to health inequity worldwide, including rheumatology. While the health system is a key proponent to health access for all, other social determinants of health also impact world health. We describe herein the current state of global healthcare disparities in rheumatology and attempts at optimizing graduate medical education and resources for optimized healthcare, international research collaborations and a future of universal health equity. We performed a comprehensive search through Pubmed using the following keywords: healthcare disparities, medical education, access to care, community health.Key Points• Healthcare disparities are ubiquitous globally, including the field of rheumatology.• The heterogeneity of global healthcare disparities emphasizes the importance of addressing unmet needs at a regional level.• A standardized approach to incorporating healthcare disparities education in the medical field is lacking. Intervening at this level provides a foundation of increasing provider awareness of regional healthcare disparities so as to establish a framework of addressing such disparities in a culturally competent manner.

Analgesic and anti-inflammatory effects and molecular mechanisms of Kadsura heteroclita stems, an anti-arthritic Chinese Tujia ethnomedicinal herb

ETHNOPHARMACOLOGICAL RELEVANCE

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by failure of spontaneous resolution of inflammation. The stem of Kadsura heteroclite (KHS) is a well-known anti-arthritic Tujia ethnomedicinal plant, which named Xuetong in folk, has long been used for the prevention and treatment of rheumatic and arthritic diseases.

AIM OF THE STUDY

The analgesic and anti-inflammatory effects and the potential mechanisms behind such effects of KHS would be investigated by using different animal models.

MATERIALS AND METHODS

The abdominal writhing episodes of mice induced by intraperitoneal injection of acetic acid and the tail-flick response induced by radiant heat stimulation were used to evaluate the analgesic effect of KHS. The number of abdominal writhing episodes of mice and the latency of tail-flick in rats were measured and recorded. In acute inflammatory models, the ear edema of mice was induced by applying xylene on the ear surface, while the paw edema of male and female rats was induced by subcutaneous injection of carrageenan into the right hind paws of animals. The carrageenan-induced paw swelling in rats were selected as an anti-acute inflammatory mechanism of KHS. Serum levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor (TNF-α) were measured by ELISA, and protein expression of cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) were detected by Western blot.

RESULTS

The maximal tolerated single dose of KHS was determined to be 26 g/kg in both sexes of mice. Pharmacological studies showed that KHS at the dose of 200 mg/kg significantly prolonged the reaction time of rats to radiant heat stimulation and suppressed abdominal writhing episodes of mice induced by intraperitoneal injection of acetic acid. KHS at the dose of 200, 400, and 800 mg/kg, showed dose-dependent inhibition of xylene-induced ear swelling in mice. KHS at the dose of 100, 200, 400, and 800 mg/kg demonstrated dose- and time-dependent suppression of paw edema induced by subcutaneous injection of carrageenan in both all rats. Mechanistic studies revealed that the anti-inflammatory effect of KHS was associated with inhibition of the production of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α and effectively decreased the expression of COX and iNOS proteins in the carrageenan-injected rat serum, paw tissues and inflammatory exudates. The positive reference drug, rotundine at a dosage of 100 mg/kg and indomethacin at a dosage of 10 mg/kg were used in both mice and rat models.

CONCLUSION

These results suggested that KHS has significant effects on analgesia and anti-inflammation with decreasing the pro-inflammation cytokines of IL-1β, IL-6, and TNF-α and inhibiting the proteins expression of COX-2 and iNOS.

Secreted Protein Acidic and Rich in Cysteine Mediated Biomimetic Delivery of Methotrexate by Albumin-Based Nanomedicines for Rheumatoid Arthritis Therapy

Rheumatoid arthritis (RA) is one of the most common chronic autoimmune diseases. Despite considerable advances in clinical treatment of RA, suboptimal response to therapy and treatment discontinuation are still unresolved challenges due to systemic toxicity. It is of crucial importance to actively target and deliver therapeutic agents to inflamed joints in order to promote in situ activity and decrease systemic toxicity. In this study, we found that SPARC (secreted protein acidic and rich in cysteine) was overexpressed in the synovial fluid and synovium of RA patients as well as mice with collagen-induced arthritis (CIA), which has been scarcely reported. Building upon the SPARC signature of RA joint microenvironment and the intrinsic high affinity of SPARC for albumin, we fabricated methotrexate-loaded human serum albumin nanomedicines (MTX@HSA NMs) and explored them as biomimetic drug delivery systems for RA therapy. Upon intravenous injection of chlorin e6-labeled MTX@HSA NMs into CIA mice, the fluorescence/magnetic resonance dual-modal imaging revealed higher accumulations and longer retention of MTX@HSA NMs in inflamed joints with respect to free MTX molecules. In vivo therapeutic evaluations suggested that the MTX@HSA NMs were able to attenuate the progression of RA with better efficacy and fewer side effects even at half  dose of administrated MTX in comparison with free MTX. By unraveling the mechanism driving the efficient accumulation of MTX@HSA NMs in RA joints and showing their ability to improve the safety and therapeutic efficacy of MTX, our work sheds light on the development of innovative anti-RA nanomedicines with a strong potential for clinical translation.

Efficacy and Safety of Tofacitinib in Chinese Patients with Rheumatoid Arthritis

Background:

Tofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis (RA). This study assessed the efficacy and safety of tofacitinib in Chinese patients with RA enrolled in Phase 3 and long-term extension (LTE) studies.

Methods:

ORAL Sync was a 1-year, randomized, placebo-controlled, Phase 3 trial. Patients received tofacitinib 5 or 10 mg twice daily (BID) or placebo advanced to tofacitinib 5 or 10 mg BID at 3 or 6 months. All patients remained on ≥1 background conventional synthetic disease-modifying antirheumatic drug. ORAL Sequel is an open-label LTE study (data-cut: March 2015; data collection and analyses were ongoing, and study database was not locked at the time of analysis; study was closed in 2017). Efficacy outcomes: American College of Rheumatology (ACR) 20/50/70 response rates and Disease Activity Score in 28 joints using erythrocyte sedimentation rate (DAS28-4 [ESR]). Patient- and physician-reported outcomes: Health Assessment Questionnaire-Disability Index (HAQ-DI), Patient and Physician Global Assessment of Arthritis, and pain (visual analog scale). Safety was assessed throughout.

Results:

ORAL Sync included 218 patients; 192 were subsequently enrolled into ORAL Sequel. In ORAL Sync, more patients achieved ACR20 (tofacitinib 5 mg BID, 67.4%; 10 mg BID, 70.6%; placebo, 34.1%) and DAS28-4 (ESR) <2.6 (tofacitinib 5 mg BID, 7.1%; 10 mg BID, 13.1%; placebo, 2.3%) with tofacitinib versus placebo at Month 6. Mean changes from baseline in HAQ-DI were greater with tofacitinib versus placebo at Month 6. In ORAL Sequel, efficacy was consistent to Month 48. Incidence rates for adverse events of special interest in tofacitinib-treated patients were similar to the global population.

Conclusions:

Tofacitinib significantly reduced signs/symptoms and improved physical function and quality of life in Chinese patients with moderate-to-severely active RA up to Month 48. The safety profile was consistent with the global population.

Clinical Trial Identifier:

NCT00856544 and NCT00413699.

Rheumatology in Egypt: back to the future

Medical knowledge in ancient Egypt had a remarkable reputation since rulers of other empires used to request the pharaoh to send them their best physician to treat their beloved ones. Many rheumatologic conditions as giant-cell arteritis, reactive arthritis and other forms of spondyloarthritis have been identified in ancient Egyptian materials. Rheumatologists in Egypt are enormously expanding and mastering the tools that aid them in enhancing the management of rheumatic diseases. More Egyptian rheumatologists are actively participating in the annual European League Against Rheumatism (EULAR) and American College of Rheumatology conferences and those attached to well known state of the art centers are increasing. EULAR certified Egyptian MSUS trainers are effectively performing regionally. This review throws light on the rheumatology practice in Egypt, its progress from ancient times passing through Egyptian medical healthcare services, education systems for rheumatologists, rheumatology associations, an overview on the spectrum of rheumatic diseases through publications in the field till future perspectives. Rheumatology in Egypt is an actively growing and dynamic specialty of medicine with considerable contributions to the world's literature. These days, persistent efforts are mandatory to raise the standard of clinical and basic research, to optimize clinical practice with regard to new biologics, to develop tailored and targeted therapies for the rheumatic diseases, and to meet the medical demands of the exponentially increasing Egyptian population. Opportunities and challenges discussed high-lighten future perspectives needed to boost the rheumatology practice in Egypt.

Salvianolic Acid B Suppresses Inflammatory Mediator Levels by Downregulating NF-κB in a Rat Model of Rheumatoid Arthritis

Background

Salvianolic acid B (SB) is a major active phyto-component of the plant Radix Salvia miltiorrhiza, which is traditionally used to treat joint pain and arthritis. The present study examined the anti-rheumatoid arthritis efficacy of SB on collagen-induced rheumatoid arthritis (CIA) in a rat model.

Material/Methods

Forty-eight rats were divided into 4 groups: Control rats treated with saline (Group I), rats subjected to CIA induction by intradermal injection of bovine collagen II type at the tail (Group II), and rats subjected to CIA and supplemented with either 20 or 40 mg/kg of SB for 28 days (group III or IV).

Results

Paw swelling, edema, arthritis score, thymus and spleen indexes, and neutrophil infiltration were significantly decreased (p<0.01) by treatment with 20 or 40 mg/kg of SB. The levels of inflammatory cytokines (interleukin-1β, -6, and -17, and TNF-α) and anti-collagen II-specific immunoglobulins (IgG₁ and IgG_2a) were markedly decreased (p<0.01), and those of antioxidant enzymes (SOD, CAT, and GSH) were significantly increased (p<0.01) in SB-treated rats. Administration with SB (20 or 40 mg/kg) resulted in lower phosphorylated IκB-α and NF-κB p65 protein levels and markedly downregulated IκB-α expression. Furthermore, CIA rats revealed the presence of highly diffused polymorphonuclear cells (PMNs) infiltration with eroded cartilage; however, these phenomena were considerably ameliorated by SB.

Conclusions

SB alleviates oxidative stress and inflammation in CIA rats, thus verifying its anti-rheumatoid arthritis property.

[Intra-articular injection of ascorbic acid/ferric chloride relieves cartilage degradation in rats with osteoarthritis]

OBJECTIVE

To assess the effect of ascorbic acid/ferric chloride (AA/FeCl₃) in attenuating cartilage damage in rats with osteoarthritis.

METHODS

Thirty adult male Wistar rats with surgically induced osteoarthritis were randomized into 2 groups for treatment with intra-articular injection of saline (control group) or AA/FeCl3 mixture (AA group) once a week starting from the third week after the operation. At 6, 9, and 12 weeks after the operation, 5 rats from each group were sacrificed for observing subchondral bone changes on X-ray films and evaluation of cartilage degeneration in the right knee joints using safranin-O/Fast green staining and a modified OARSI scoring system. The degradation of the cartilage matrix was observed by immunohistochemical staining for type Ⅱ collagen.

RESULTS

X-ray examination in saline control group revealed the presence of osteophytes and narrowing of the joint space at 9 weeks, and the joint line disappeared at 12 weeks after the surgery; only slight irregularity of the articular surface was observed in the AA group at 9 and 12 weeks. OARSI scores were significantly lower in AA group than in the control group at 9 weeks (18.67±0.67 vs 12.17±2.75; P < 0.05) and 12 weeks (20.11±1.84 vs 13.77± 0.40; P < 0.05) but not at 6 weeks after the surgery. The content of type 2 collagen in AA group was significantly higher than that in the control group at 6 weeks (0.36±0.039 vs 0.49±0.029; P < 0.05) and 9 weeks after the surgery (0.25±0.041 vs 0.38±0.040; P < 0.05).

CONCLUSIONS

Early intra-articular injection of AA/FeCl₃ can effectively delay the progression of post-traumatic osteoarthritis in rats.

The usage of biological DMARDs and clinical remission of rheumatoid arthritis in China: a real-world large scale study

The aims of this study are to characterize the biological disease-modifying antirheumatic drug (bDMARD) usage patterns in real-life and examine the remission rate of rheumatoid arthritis (RA) patients receiving bDMARDs in routine clinical practice in China. Consenting RA patients (≥18 years) from 15 teaching hospitals and receiving marketed bDMARDs were included. In total, 802 patients (81.3 % women, 49.0 ± 13.9 years) were included; 89.5 % were receiving a combination of bDMARDs and conventional synthetic DMARDs (csDMARDS), whereas 10.5 % were receiving bDMARD monotherapy. Etanercept (including Enbrel® and local brand Yi Sai Pu® and Qiangke®), tocilizumab, adalimumab, and infliximab were used by 66.6 %, 17.0 %, 7.5 %, and 6.6 % patients, respectively. Etanercept was used at a mean weekly dose of 38.2 ± 15.6 mg for 25.5 ± 47.0 weeks and tocilizumab at 94.5 ± 21.9 mg for 4.7 ± 7.5 weeks. Overall rate of remission was 12.6 %, 5.4 % , and 3.5 % based on DAS28, CDAI, and SDAI scores, respectively. Compared with patients receiving bDMARDs for <3 months, those receiving bDMARDs for ≥3 months exhibited significantly lower DAS28 scores (p < 0.0001), and a significantly higher proportion of patients who received bDMARDs for ≥12 months achieved the treatment goal (remission or low disease activity, 62.5 % vs. 18.3 %, p < 0.0001). Patients receiving combination therapy with csDMARDs exhibited lower DAS28 scores than patients receiving bDMARD monotherapy (4.3 vs. 4.8, p = 0.011). This large-scale real-world study showed that bDMARD usage patterns in routine clinical practice in China were in accordance with international guidelines for RA management despite the short treatment duration. Longer duration of bDMARD usage and combination therapy showed a favored outcome of RA.