The etiology of rheumatoid arthritis

Natural product extract fractions as potential arthritis treatments: A detailed analysis using in-silico, in-vivo, and in-vitro methods

Two characteristics of the systemic autoimmune disease rheumatoid arthritis (RA) include extra-articular involvement and inflammatory arthritis. It is a long-term inflammatory condition that mostly affects the synovial joints and is often triggered by a confluence of environmental factors, including tobacco use, and genetics. The review investigates natural products' role in arthritis through three key approaches. In-silico analysis identifies molecular mechanisms and targets of these products, revealing their potential for therapeutic use. In-vivo studies evaluate how well these products work and their safety in reducing joint inflammation. In-vitro studies focus on how these compounds interact at the cellular level and their effects on signaling pathways. Together, these approaches offer a comprehensive understanding of how natural products could benefit arthritis management. This review focuses on translational studies and highlights the possible role of natural compounds as adjunctive therapies to conventional arthritis treatments. In conclusion, this study indicates that natural products have potential advantages in treating osteoarthritis and rheumatoid arthritis based on in-silico analysis which shows anti-inflammatory effects, in-vivo studies that reduce joint inflammation, and in-vitro studies that amplify arthritis management. To improve the therapeutic advantages of natural products utilized for treating arthritis, an all-inclusive examination has been done to give direction for the following research efforts.

Resveratrol nanocrystals based dissolving microneedles with highly efficient for rheumatoid arthritis

Rheumatoid arthritis (RA) is a common immune disease characterized mainly by erosive arthritis with extensive clinical sequelae. Resveratrol (Res) has pharmacological effects in the treatment of RA, but it has not been widely used in the clinic due to its poor water solubility and low bioavailability. In this study, a drug delivery system (Res-NC MNs) of dissolved microneedles (MNs) loaded with Res nanocrystals (NC) was designed for the treatment of RA. Res-NC MNs can improve the drawbacks of long-term oral drug delivery with toxic side effects and low compliance associated with intra-articular drug delivery. In this study, Res-NC was prepared by media milling and loaded into soluble microneedles prepared from hyaluronic acid (HA) by vacuum casting for the treatment of RA. HA has high mechanical strength and can penetrate the cuticle layer of the skin for effective drug delivery. In in vivo pharmacodynamic experiments, Res-NC MNs achieved better therapeutic efficacy in the treatment of RA compared with oral Res. These findings suggest that Res-NC MNs may be an effective and promising drug delivery strategy for the treatment of RA.

Integrative metabolomic-proteomic analysis uncovers a new therapeutic approach in targeting rheumatoid arthritis

OBJECTIVE

Rheumatoid arthritis (RA) is a chronic inflammatory condition that, despite available approaches to manage the disease, lacks an efficient treatment and timely diagnosis. Using the most advanced omics technique, metabolomics and proteomics approach, we explored varied metabolites and proteins to identify unique metabolite-protein signatures involved in the disease pathogenesis of RA.

METHODS

Untargeted metabolomics (n = 20) and proteomics (n = 60) of RA patients' plasma were carried out by HPLC/LC-MS/MS and SWATH, respectively and analyzed by Metaboanalyst. The targets of metabolite retrieved by PharmMapper were matched with SWATH data, and joint pathway analysis was carried out. An in-vitro study of metabolites in TNF-α induced SW982 cells was conducted by Western, RT-PCR, scratch, and ROS scavenging assay. The effect of GUDCA was also evaluated in the CIA rat model.

RESULTS

A Total of 82 metabolites and 231 differential proteins were revealed. Porphyrin and chlorophyll pathway and its metabolite Glycoursodeoxycholic acid (GUDCA) was found to be significantly altered. In vitro analysis has shown that GUDCA reduces inflammation thus offering protection against ROS production and cell proliferation. PharmMapper analysis revealed that GUDCA was significantly linked with identified SWATH proteins insulin like growth factor-1(IGF1), and Transthyretin (TTR) and it upregulates the expression of IGF1 and downregulates the expression of TTR in both in vitro and in vivo models.

CONCLUSION

GUDCA was found to possess antioxidative, antiproliferative properties and an effective anti-inflammatory property at a low dosage. It may be considered as a potential therapeutic option for reducing the inflammatory parameters associated with RA.

MicroRNAs as Biomarker in Rheumatoid Arthritis: Pathogenesis to Clinical Relevance

MicroRNAs (miRNAs) have emerged as intricate players in rheumatoid arthritis (RA), holding promise as discerning biomarkers for diagnostic and prognostic purposes. The lack of sensitivity and specificity in current diagnostic techniques, such as rheumatoid factor (RF) and anti-citrullinated protein antibodies (ACPA), causes diagnosis delays in RA. The miR-146a and miR-155 act in inflammatory cascades and reduce joint deterioration, and miR-223 is paradoxical, acting differently in different illness scenarios. The microenvironment of RA is shaped by the complex modulation of gene expression and cytokine dynamics by miR-126 and miR-24. miRNAs serve as a promising candidate for precision medicine in the management of RA. There are obstacles encountered in validation, delivery optimization, and off-target effect mitigation before miRNA-based biomarkers may be applied in clinical settings. Machine learning (ML) and artificial intelligence (AI) have been used to integrate miRNA expression patterns with clinical data to greatly advance the treatment of RA. Because of the disease's inherent complexity and variability, these state-of-the-art models provide accurate predictions regarding the onset, development, and response to treatment of RA. By using clinical information and miRNA expression data, ML algorithms are revolutionizing the treatment of RA by predicting the onset and course of the disease with remarkably high accuracy. The development of therapeutic modalities and miRNA profiling has great potential to transform the diagnosis, prognosis, and treatment of RA, providing fresh hope for better patient outcomes.

Insights into the complexities of Citrullination: From immune regulation to autoimmune disease

Citrullination, a post-translational modification that changes arginine to citrulline in proteins, is vital for immune response modulation and cell signaling. Catalyzed by peptidyl arginine deiminases (PADs), citrullination is linked to various diseases, particularly autoimmune disorders like rheumatoid arthritis (RA). Citrullinated proteins can trigger the production of anti-citrullinated protein antibodies (ACPAs), included in RA classification criteria. The immune response to citrullination involves both innate and adaptive immunity, affecting monocytes/macrophages, neutrophils, dendritic cells, natural killer cells, B cells, and T cells. Citrullination contributes to disease development in RA and other conditions such as multiple sclerosis, sepsis, and cancer. Therapeutic strategies targeting citrullination and its effects are being explored, including B cell depletion therapies, T cell-directed approaches, PAD inhibitors, and citrullinated peptide-based vaccines. Understanding the interplay between citrullination and the immune system may lead to novel diagnostic tools and targeted therapies for autoimmune diseases and beyond.

The Role and Research Progress of ACPA in the Diagnosis and Pathological Mechanism of Rheumatoid Arthritis

An autoimmune condition known as rheumatoid arthritis (RA) is characterized by persistent polyarticular inflammation. Within two years of the disease's onset, irreparable bone and joint deterioration can occur as a result of the inflammatory course of the illness, leading to joint deformity and loss of function. In most patients diagnosed with RA, a range of autoantibodies, particularly anti-citrullinated protein antibodies (ACPA), can be detected months to years before the onset of clinically recognizable disease. Additionally, an increasing number of studies suggest that ACPA is involved in the pathogenesis of RA and may play a direct pathogenic role in the disease. This paper focuses on the role of ACPA in the pathomechanism of RA and discusses its unique clinical applications for the early identification and prediction of RA, as well as the influencing factors. Moreover, this article outlines the association of ACPA-positive (ACPA+) RA with other autoimmune diseases.

PPARγ Functional Deficiency Expedited Fatty Acid Utilization in the Liver: A Foundation of Inflammatory Adipokine-Induced Hypolipemia in Rheumatoid Arthritis

Triglyceride (TG) and its derivatives tend to be decreased in rheumatoid arthritis (RA) patients' blood when inflammation progresses. Aside from the role as a lipid buffer, white adipose tissue (WAT) contributes to this abnormality via adipokines, which regulate many metabolic signals. This work investigated adipokine-caused hepatic changes and their involvement in RA-related hypolipemia. Given their immune similarities with RA and pathological representativeness, adjuvant-induced arthritis (AIA) rats and antigen-induced arthritis (AA) mice were adopted. Adipokine levels in the liver were quantified, and their hepatic conditions were assessed by oxidative/enzymatic indicators. Besides kit-based metabolite quantification, fatty acid levels in blood were accurately determined by GC-MS. Metabolic differences between healthy and AIA rats were further characterized by UPLC-MS2. In vitro, preadipocytes were stimulated by RA/AIA blood serum or together with rosiglitazone, a PPARγ agonist. The medium was used to culture HepG2 cells. Some AIA rats were subjected to adipectomy or rosiglitazone therapies. Being WAT-released mediators, IL-1β, IL-6, MCP-1, adiponectin, and visfatin were apparently increased in AIA/AA rodent models' liver, causing oxidative stress escalation, liver injuries, and fatty acid oxidation acceleration. This metabolic change was coincided to expression increase of CD36, FABP1, ATGL, and CPT-1A. PPARγ deficiency occurred both in vivo and in vitro under rheumatic conditions. RA serum reduced PPARγ expression and impaired its inhibition on NF-κB transcription activity in preadipocytes, which then led to excessive secretion of inflammatory adipokines. The corresponding medium down-regulated PPARγ and promoted expression of lipid catabolic enzymes in HepG2 cells. These effects were abrogated by rosiglitazone. Both the therapies impeded inflammatory secretion of WAT and fat catabolism of the liver. These data demonstrate that RA potentiates the capacity of WAT to secrete inflammatory adipokines. The resulting condition represses PPARγ expression and disrupts TG anabolism/catabolism balance in the liver. Because hepatocytes utilize more lipids but synthesize less, hypolipemia develops.

Rheumatoid Factor Titer as an Indicator of the Risk of Rheumatoid Arthritis Activity: Dose-Effect Analysis with the Restricted Cubic Spline Model

Background

Rheumatoid factor (RF) titer is known to be correlated to rheumatoid arthritis (RA) activity, but the ideal cut-off titer of RF remains unclear. Here, the relationship between RF titer and RA activity was investigated in order to determine the ideal RF value indicative of the risk of RA activity.

Methods

Clinical data from 2044 eligible patients were collected from the First Affiliated Hospital of Anhui Medical University from February 2022 to October 2023. A restricted cubic spline (RCS) model was used to evaluate the relationship between RF titer and RA activity.

Results

Data from a total of 2044 patients with RA were collected and analyzed. Multivariate logistic regression analysis revealed that higher RF levels were significant predictors of the risk of RA activity calculated according to the disease activity score 28 (DAS28)-erythrocyte sedimentation rate (ESR) (OR = 2.020, 95% CI = 1.457-2.801, P < 0.001) and DAS28-C reactive protein (CRP) (OR = 1.526, 95% CI = 1.092-2.131, P = 0.013), after the results were adjusted for potential covariates. The relationship between log2RF and the risk of RA activity was non‑linear in the RCS model (P < 0.05). The cutoff value of RF titers for determining the risk of RA activity was 65.80 IU/mL. When RF exceeded the cutoff value, the risk of RA activity based on DAS28-ESR increased by 99.2% and the risk of RA activity based on DAS28-CRP increased by 62.8% (P < 0.001).

Conclusion

The risk of RA activity increased non-linearly with the continuous change in RF titer.

Emerging influence of RNA post-transcriptional modifications in the synovial homeostasis of rheumatoid arthritis

Rheumatoid arthritis (RA) is an important autoimmune disease that affects synovial tissues, accompanied by redness, pain, and swelling as main symptoms, which will limit the quality of daily life and even cause disability. Multiple coupling effects among the various cells in the synovial micro-environment modulate the poor progression and development of diseases. Respectively, synovium is the primary target tissue of inflammatory articular pathologies; synovial hyperplasia, and excessive accumulation of immune cells lead to joint remodelling and destroyed function. In general, epigenetic modification is an effective strategy to regulate dynamic balance of synovial homeostasis. Several typical post-transcriptional changes in cellular RNA can control the post-transcriptional modification of RNA structure. It can inhibit important processes, including degradation of RNA and nuclear translocation. Recent studies have found that RNA modification regulates the homeostasis of the synovial micro-environment and forms an intricate network in the "bone-cartilage-synovium" feedback loop. Aberrant regulation of RNA methylation triggers the pathological development of RA. Collectively, this review summarises recent advanced research about RNA modification in modulating synovial homeostasis by making close interaction among resident synovial macrophages, fibroblasts, T cells, and B cells, which could display the dramatic role of RNA modifications in RA pathophysiological process and perform the promising therapeutic target for treating RA.

Eukaryotic translation initiation factor 6-mediated ribosome biogenesis promotes synovial aggression and inflammation by increasing the translation of SP1 in rheumatoid arthritis

INTRODUCTION

Fibroblast-like synoviocytes (FLSs) play critical roles in synovial inflammation and aggression in rheumatoid arthritis (RA). Here, we explored the role of eukaryotic translation initiation factor 6 (eIF6) in regulating the biological behaviors of FLSs from patients with RA.

METHODS

FLSs were isolated from the synovial tissues of RA patients. Gene expression was assessed via RT-qPCR, and protein expression was evaluated via Western blotting or immunohistochemistry. Proliferation and nascent peptide synthesis were evaluated via EdU incorporation and HPG labeling, respectively. Cell migration and invasion were observed via Transwell assays. Polysome profiling was conducted to analyze the distribution of ribosomes and combined mRNAs. The in vivo effect of eIF6 inhibition was evaluated in a collagen-induced arthritis (CIA) rat model.

RESULTS

We found that eIF6 expression was elevated in FLSs and synovial tissues from RA patients compared to those from healthy controls and osteoarthritis patients. Knockdown of eIF6 inhibited the migration, invasion, inflammation, and proliferation of FLSs from patients with RA. Mechanistically, eIF6 knockdown downregulated ribosome biogenesis in FLSs from with RA, leading to a decrease in the proportion of polysome-associated specificity protein 1 (SP1) mRNA and a subsequent reduction in the translation initiation efficiency of SP1 mRNA. Thus, eIF6 controls SP1 expression through translation-mediated mechanisms. Interestingly, intra-articular eIF6 siRNA treatment attenuated symptoms and histological manifestations in CIA rats.

CONCLUSIONS

Our findings suggest that an increase in synovial eIF6 might contribute to rheumatoid synovial inflammation and aggression and that targeting eIF6 may have therapeutic potential in RA patients.

Bidirectional association between rheumatoid arthritis and chronic obstructive pulmonary disease: a systematic review and meta-analysis

Background

Rheumatoid arthritis (RA) and chronic obstructive pulmonary disease (COPD) are prevalent and incapacitating conditions, sharing common pathogenic pathways such as tobacco use and pulmonary inflammation. The influence of respiratory conditions including COPD on RA has been observed, meanwhile RA may constituting one of the risk factors for COPD. It unclear that whether a bidirectional associate between RA and COPD. Our study aims to explore the bidirectional relationship between RA and COPD.

Methods

We systematically searched PubMed, Cochrane Library, and Embase for observational studies from the databases inception to February 20, 2024, utilizing medical subject headings (MeSH) and keywords. We included studies in which RA and COPD were studied as either exposure or outcome variables. Statistical analyses were conducted employing STATA software (version 14.0). The relationship was reported as odds ratios (OR) and corresponding 95% confidence intervals (CI). Publication bias was assessed using funnel plots and Egger's regression.

Results

Nineteen studies with 1,549,181 participants were included. Risk of bias varied from low to moderate, with evidence levels rated as low or very low. Pooled analysis revealed a significant association between RA and increased COPD risk (OR=1.41, 95%CI 1.13 to 1.76, I2 = 97.8%, P=0.003). Subgroup analyses showed similar COPD risk elevations in both of genders, seropositive/seronegative RA, cohort and case control studies. Additionally, there was a significant RA risk increase among those with COPD (OR=1.36, 95%CI 1.05 to 1.76, I2 = 55.0%, P=0.022), particularly among females and seropositive RA, and cohort studies.

Conclusion

The meta-analysis identifies a significant bidirectional association between RA and COPD, emphasizing mutually increased risk. Recognizing this connection may can inform proactive approaches to disease prevention and management, potentially reducing the public health burden and improving quality of life.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42024518323.

Circ_0011058 alleviates RA pathology through the circ_0011058/miR-335-5p/CUL4B signal axis

Our previous study found that Cullin 4B (CUL4B) inhibited rheumatoid arthritis (RA) pathology through glycogen synthase kinase-3beta (GSK3β)/canonical Wnt signalling pathway. In this work, pre-experiment and bioinformatics analysis suggested that circ_0011058 may lead to the up-regulation of CUL4B expression by inhibiting miR-335-5p. Therefore, we studied whether circ_0011058 can promote the expression of CUL4B through sponging the miR-335-5p and further promote the pathological development of RA. Bioinformatics prediction, real-time quantitative PCR (RT-qPCR), western blot (WB), double luciferase reporter gene and other relevant methods were used to study the inhibition of circ_0011058 on RA pathology and its molecular mechanism. Results showed that the expression of circ_0011058 was significantly increased in adjuvant arthritis (AA) rats and RA fibroblast-like synoviocytes (FLS). The knockout of circ_0011058 inhibited the proliferation of AA FLS and RA FLS, decreased the levels of interleukin-1 beta (IL-1β), interleukin 6 (IL-6), interleukin 8 (IL-8), and inhibited the expression of matrix metalloproteinase 3 (MMP3), fibronectin, which showed that circ_0011058 had a strong role in promoting RA pathology. Furthermore, miR-335-5p expression was reduced in AA rats and RA FLS. The highly expressed circ_0011058 directly sponged the miR-335-5p, which led to the increase of CUL4B expression and promoted the activation of the GSK3β/canonical signalling pathway. Finally, we confirmed that miR-335-5p mediated the roles of circ_0011058 in promoting RA pathological development, which showed that the circ_0011058/miR-335-5p/CUL4B signal axis was involved in RA pathology. This work was of great significance for clarifying the roles of circ_0011058 in RA pathology, and further work was needed to establish whether circ_0011058 was a potential therapeutic target or diagnostic marker for RA.

Efficacy and safety of abatacept in preclinical rheumatoid arthritis: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

Abatacept is a biological DMARD that has been used for the treatment of rheumatoid arthritis. However, the literature on its use in preclinical Rheumatoid arthritis (RA) is limited. We conducted this meta-analysis to evaluate the safety and efficacy of abatacept in preclinical RA.

STUDY DESIGN

This meta-analysis intends to assess the effectiveness and safety of abatacept in persons who are at a high risk of developing rheumatoid arthritis (RA) during the pre-clinical phase. The analysis comprises of three randomized controlled trials (RCTs) involving atotal of 367 participants. The study follows the procedures specified in the Cochrane Handbook for Systematic Reviews of Interventions and the PRISMA statemen RESULTS: The meta-analysis found that abatacept significantly reduced the risk of developing RA compared to placebo (RR: 0.67; 95 % CI: 0.51 to 0.89; P = 0.006) and improved tender joint count (SMD: -0.40; 95 % CI: -0.63 to -0.18; P = 0.0004). Additionally, abatacept demonstrated a significant reduction in functional disability (SMD: -1.51; 95 % CI: -1.91 to -1.11; P < 0.00001), though no significant difference was observed in pain reduction. Safety analysis revealed no significant differences in the occurrence of infections, malignancy, or discontinuation due to adverse events between the abatacept and placebo groups.

CONCLUSION

Abatacept is a promising treatment option for slowing down the development of RA in people who are at high risk. It has a positive safety profile. Additional studies with extended follow-up periods are required to validate these findings and offer more substantial data.

Kaempferol Improved Rheumatoid Arthritis by Regulating the Immune Imbalance of Treg/Th17

OBJECTIVE

The objective of this study was to explore the therapeutic effects of kaempferol (Kae) on rheumatoid arthritis (RA) and to elucidate the underlying mechanisms.

METHODS

The collagen-induced arthritis (CIA) model was established using collagen II to induce RA. Mice were treated with Kae at a dose of 25 or 50 mg/kg/day via gavage. Pathological changes in the ankle joint were analyzed. Enzyme-linked immunosorbent assay (ELISA) was employed to measure the levels of inflammatory factors. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to assess the expression of genes associated with the balance of regulatory T (Treg)/T helper 17 (Th17) cells. Flow cytometry was utilized to determine the Treg/Th17 ratio. Furthermore, these techniques were employed to evaluate the impact of miR-34a and Foxp3 dysregulation on cellular functions in RA under the influence of Kae. Dual luciferase reporter assay was conducted to analyze the binding of miR-34a to Foxp3.

RESULTS

Treatment with Kae led to a downregulation of receptor-related orphan receptor gamma t (RORγt) and IL-17 expression, and an upregulation of Foxp3, IL-10, and TGF-β expression in CIA mice. Kae intervention inhibited the production of proinflammatory cytokines and increased the production of anti-inflammatory cytokines. Furthermore, Kae treatment suppressed the expression of miR-34a, which was identified as a target of miR-34a. Finally, Kae regulated Treg/ Th17 balance-related genes and cellular inflammation through the miR-34a/Foxp3 axis.

CONCLUSION

The study demonstrated that Kae effectively ameliorates CIA in mice by modulating the Treg/Th17 balance and related genes via the miR-34a/Foxp3 axis. These findings suggest that Kae may serve as a promising therapeutic agent for the treatment of RA and for restoring immune homeostasis.

Helper T cells: A potential target for sex hormones to ameliorate rheumatoid arthritis? (Review)

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease whose etiology is not fully understood. Defective peripheral immune tolerance and subsequent mis‑differentiation and aberrant infiltration of synovium by various immune cells, especially helper T (Th) cells, play an important role in the development of RA. There are significant sex differences in RA, but the results of studies on the effects of sex hormones on RA have been difficult to standardize and hormone replacement therapy has been limited by the potential for serious side effects. Existing research has amply demonstrated that cellular immune responses are largely determined by sex and that sex hormones play a key role in Th cell responses. Based on the aforementioned background and the plasticity of Th cells, it is reasonable to hypothesize that the action of sex hormones on Th cells will hopefully become a therapeutic target for RA. The present review discussed the role of various Th cell subsets in the pathogenesis of RA and also explored the role of sex hormones on the phenotype and function of these aberrantly regulated immune cells in RA as well as other pathologic effects on RA.

Dental service use among adults with incident type 2 diabetes, rheumatoid arthritis or inflammatory bowel disease

OBJECTIVES

It is not clear if or how the incidence of systemic conditions like type 2 diabetes mellitus (DM2), rheumatoid arthritis (RA) or inflammatory bowel disease (IBD) affects dental service utilization. Using nationwide Danish register data, the aim of this study was to analyse the use of dental services 7 years before and after being diagnosed with DM2, RA or IBD between 1997 and 2011.

METHODS

Information about incident DM2 was obtained from the Register for Selected Chronic Diseases and Severe Mental Disorders, and incident RA and IBD were defined based on diagnosis codes of hospital contacts identified through the National Patient Register. Separately, for each of the three conditions, each individual with the incident condition was matched to one control individual based on age, gender, country of origin, municipality of residence, highest completed education, the main source of income and income using coarsened exact matching in the year of incidence. The use of dental services and treatments received within each calendar year from 7 years before to 7 years after getting the condition were analysed with generalized estimating equations.

RESULTS

People with incident DM2 were less likely (by seven percentage points) to be dental service users within a year than people without incident DM2 for a period extending from up to 7 years prior to 7 years after the diagnosis. This difference even slightly increased after the diagnosis. Those with incident IBD exhibited a consistently but modestly higher proportion of dental service use (three percentage points) than those without incident IBD before and after the diagnosis. Differences in the use of services between those with or without incident RA were minor. For all three systemic diseases, detected differences mainly mirrored differences in the provision of supragingival scaling and restorative treatment.

CONCLUSIONS

The findings suggest that the impact of these three systemic conditions on dental service use was minor.

Breaking barriers: advancing cellular therapies in autoimmune disease management

Autoimmune diseases occur due to a dysregulation within the immune system, leading to an aberrant assault on the organism's own tissues. The pathogenesis of these conditions is multifactorial, encompassing intricate interplays among genetic predispositions, environmental determinants, and hormonal fluctuations. The spectrum of autoimmune diseases is broad, impacting a multitude of organ systems, with notable examples such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), multiple sclerosis (MS), psoriasis, and vitiligo. Despite substantial progress in therapeutic interventions over recent years, a definitive cure for autoimmune diseases has yet to be realized, with existing modalities largely providing palliative care. Cellular therapy is considered the fourth pillar in the management of oncological disorders subsequent to surgical resection, radiotherapy, and chemotherapy. Cellular therapies have shown potential in augmenting immune competence and eliminating of targeted neoplastic cells in a spectrum of cancers. As targeting specific molecules on the surface of autoreactive B and T cells, such as CD19, BCMA, CD20, and CTLA-4, cellular therapies are emerging as promising approaches for the treatment of autoimmune diseases. This review delineates the advancements in the application of cellular therapies applied recently for autoimmune diseases and proposes considerations for the advancement of novel therapeutic strategies.

High Humidity Alters Myeloid-Derived Suppressor Cells in Spleen Tissue: Insights into Rheumatoid Arthritis Progression

Background

Rheumatoid arthritis (RA) is an autoimmune disease characterized by joint inflammation and bone destruction, leading to severe complications. Previous research has suggested that high humidity conditions may exacerbate RA, however, the underlying mechanisms remain unclear. Furthermore, there is a lack of evidence linking humidity to the worsening of RA symptoms in animal models.

Methods

The Collagen-induced arthritis (CIA) mouse model was established using C57BL/6 mice. The arthritis status of the mice was evaluated under two distinct humidity conditions (50% and 80%). The aim of the present study was to investigate the impact of elevated humidity levels on the types of splenic cells present using mass spectrometry flow. Additionally, the study utilized MDSCs, which are significantly upregulated by high humidity, to assess the levels of oxidative stress and conducted mRNA sequencing of sorted MDSCs to investigate their impact on arthritis in CIA mice.

Results

Compared to normal humidity, high humidity exacerbated arthritis incidence in mice, resulting in increased arthritis scores, swelling, serum autoantibodies (anti-COII and anti-CCP), and upregulation of pro-inflammatory cytokines. Significant variations were observed in the spleen index under high humidity condition, accompanied by noticeable inflammatory alterations. Moreover, elevated humidity levels induced a substantial modulation in MDSCs population in the spleen of CIA mice, along with alterations in oxidative stress markers such as heightened serum ROS levels, and increased expression of COX, SOD, and Nrf2 mRNA. Following successful sorting of MDSCs, mRNA sequencing revealed a decrease in the expression of Rap1 signaling pathway under high humidity environment, which may contribute to the increase of MDSCs cells and aggravate the progression of RA disease.

Conclusion

A comprehensive analysis of the available data reveals a detrimental impact of high humidity on MDSCs numbers within spleen tissue, with potential implications for the development of RA.

Transdermal Delivery of Tofacitinib Citrate via Mannose-Decorated Transferosomes Loaded with Tofacitinib Citrate in Arthritic Joints

Transdermal drug delivery systems are a promising option for the treatment of rheumatoid arthritis (RA) because they can lower systemic adverse effects of immunosuppressants. Janus kinase (JAK) inhibitors were found to be effective for the treatment of RA by inhibiting the JAK-STAT pathway and preventing autoimmune joint destruction. The aim of this study is to deliver tofacitinib (a JAK 1 and 3 inhibitor) through mannose-decorated transferosomes (MDTs) directly to inflamed joints. Transferosomes are composed of phospholipids, Cremophor A25, PEG400, Labrafac lipophile, and oleic acid to enhance the permeation of tofacitinib and control nanovesicle size (∼70-200 nm). Permeation through rat skin was evaluated, where the skin permeation of MDTs (Q24: 38.8 ± 9.82 μg/cm2) and flux (0.5311 ± 0.072 μg/cm2/h) were significantly greater than those of the uncoated transferosomes (Q24 of T1: 1.522 ± 0.329 μg/cm2, Q24 of T2: 3.5002 ± 0.998 μg/cm2, and Q24 of T3: 18.226 ± 5.25 μg/cm2). In addition, MDTs seem to permeate the skin intact, as shown by the transmission electron microscopy (TEM) images of the recipient buffer removed from the Franz diffusion cell. A histopathology assay was performed during the in vivo evaluation of MDTs in an arthritic rat model, in which, significantly less inflammation was observed when MDTs were applied directly to the joint compared to when applied to the dorsal skin and untreated arthritic joints. Furthermore, significantly lower tumor necrosis factor-α (TNFα), IL-6, and IL-1β levels (P < 0.05) were detected by enzyme-linked immunosorbent assay (ELISA) in homogenates of the joints treated with MDTs than in untreated arthritic joints. In conclusion, this study proposed effective MDTs that could deliver tofacitinib directly to inflamed joints possibly by targeting the macrophages circulating in the proximity of the site of inflammation.

Metabolic Regulation of Inflammation: Exploring the Potential Benefits of Itaconate in Autoimmune Disorders

Itaconic acid and its metabolites have demonstrated significant therapeutic potential in various immune diseases. Originating from the tricarboxylic acid cycle in immune cells, itaconic acid can modulate immune responses, diminish inflammation, and combat oxidative stress. Recent research has uncovered multiple mechanisms through which itaconic acid exerts its effects, including the inhibition of inflammatory cytokine production, activation of anti-inflammatory pathways, and modulation of immune cell function by regulating cellular metabolism. Cellular actions are influenced by the modulation of metabolic pathways, such as inhibiting succinate dehydrogenase (SDH) activity or glycolysis, activation of nuclear-factor-E2-related factor 2 (Nrf2), boosting cellular defences against oxidative stress, and suppression of immune cell inflammation through the NF-κB pathway. This comprehensive review discusses the initiation, progression, and mechanisms of action of itaconic acid and its metabolites, highlighting their modulatory effects on various immune cell types. Additionally, it examines their involvement in immune disease like rheumatoid arthritis, multiple sclerosis, type 1 diabetes mellitus, and autoimmune hepatitis, offering greater understanding for creating new therapies for these ailments.

Mechanism of action of Nrf2 and its related natural regulators in rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovitis that can lead to joint deformities. To date, more than 18 million individuals worldwide have been diagnosed with RA, making it one of the most prevalent autoimmune diseases globally and posing a significant threat to public health and safety. Due to the complex pathogenesis of the disease, which involves autoimmunity, genetics, inflammation and oxidative stress in the body's tissues, the current drug therapy generally targets a single molecule, and effective and efficient drugs involving multiple levels and targets are lacking; thus, there is an urgent need for high-quality research and treatment in this field. Nuclear transcription factor erythroid 2-associated factor 2 (Nrf2) plays a crucial role in cellular resistance to oxidative stress and electrophilic attacks and is a potential pharmacological target for chronic disease treatment. While currently no drugs that target Nrf2 have been approved specifically for RA treatment, such an approach holds great significance. In recent years, the use of natural products to treat RA and other chronic conditions has become increasingly widespread because of their superior efficacy and minimal side effects. Therefore, this article provides a review of the mechanism of Nrf2 in RA and summarizes natural products that target Nrf2 and its associated pathways in the treatment of RA, aiming to offer new insights and strategies for the prevention and management of RA.

Clinical Characteristics of Young-Onset Versus Elderly-Onset Rheumatoid Arthritis: A Systematic Review and Meta-Analysis

Rheumatoid arthritis (RA) is a chronic inflammatory disease with a prevalence of 1%, mainly affecting women aged 25-45. It is classified by the age of onset into young-onset rheumatoid arthritis (YORA, 16-65 years) and elderly-onset rheumatoid arthritis (EORA, over 65 years), with EORA often presenting suddenly with systemic symptoms and large joint involvement due to age-related immune changes. This systematic review and meta-analysis compare the clinical and epidemiological characteristics of EORA and YORA. Observational studies were selected from PubMed, Scopus, Embase, Web of Science, and the Cochrane Central Database up to November 2023, focusing on a comparative analysis of both disease types with similar clinical progression and treatment duration limited to one month. Statistical analysis was performed in RStudio (Version 4.1.3, Posit Software, Boston, MA) using the "meta" package, applying a random effects model, inverse variance method, and Hartung-Knapp adjustment. Results for continuous variables were combined and grouped using the Cochrane formula, with medians and interquartile ranges transformed for uniformity. Four studies met the criteria. A trend was observed toward higher disease activity at diagnosis in the EORA group (mean difference (MD: 0.19, 95% CI -1.90 to 2.27), indicated by Disease Activity Score-28 (DAS28) and Simplified Disease Activity Index (SDAI) indices (MD 6.17, 95% CI -20.60 to 32.94). The EORA group also had higher Health Assessment Questionnaire (HAQ) scores (MD 0.21, 95% CI -0.03 to 0.46) and a greater number of painful (MD 1.31, 95% CI -0.86 to 3.47) and swollen joints (MD 2.35, 95% CI 0.77 to 3.92). Extra-articular manifestations, including rheumatoid nodules, lung involvement, and secondary Sjögren's syndrome, were more common in EORA patients (p < 0.004). In conclusion, the findings suggest that patients with EORA present with more intense disease activity at onset, a higher prevalence of extra-articular manifestations, greater levels of disability, and more pronounced radiographic changes. Despite these initial differences, EORA patients ultimately achieve long-term remission rates similar to those with YORA.

Gut microbiota and autoimmune diseases: Insights from Mendelian randomization

In recent years, the scientific community has shown interest in the role of gut microbiota in the development of autoimmune diseases (AID). Although observational studies have revealed significant associations between gut microbiota and AID like rheumatoid arthritis, systemic lupus erythematosus, and multiple sclerosis, these connections do not necessarily imply causality. Mendelian randomization (MR) approach has been extensively employed to investigate the causal relationship. Relevant MR study findings indicate that a reduction in beneficial microbial populations, particularly Bifidobacterium and Lactobacillus, and an increase in potential pathogenic microbes, is correlated with an elevated AID risk. Given the innovative potential of MR in unraveling the etiopathogenesis of AIDs, this article offers an overview of this methodological approach and its recent applications in AID research.

Impaired Development of Collagen Antibody-Induced Arthritis in Rab44-Deficient Mice

BACKGROUND

Rheumatoid arthritis (RA) is an autoimmune disease characterized by immune cell-mediated joint inflammation and subsequent osteoclast-dependent bone destruction. Collagen antibody-induced arthritis (CAIA) is a useful mouse model for examining the inflammatory mechanisms in human RA. Previously, we identified the novel gene Rab44, which is a member of the large Rab GTPase family and is highly expressed in immune-related cells and osteoclasts.

METHODS

In this study, we induced CAIA in Rab44-knockout (KO) mice to investigate the effects of Rab44 on inflammation, cell filtration, and bone destruction.

RESULTS

Compared with wild-type (WT) mice, Rab44-KO mice showed reduced inflammation in arthritis under CAIA-inducing conditions. Rab44-KO CAIA mice exhibited reduced cell filtration in the radiocarpal joints. Consistent with these findings, Rab44-KO CAIA mice showed decreased mRNA levels of arthritis-related marker genes including genes for inflammation, cartilage turnover, bone formation, and bone absorption markers. Rab44-KO CAIA mice exhibited predominant infiltration of M2-type macrophages at inflammatory sites and reduced bone loss compared to WT CAIA mice.

CONCLUSIONS

These results indicate that Rab44 deficiency reduces the progression of inflammation in CAIA in mice.

TLR2 reprograms glucose metabolism in CD4+ T cells of rheumatoid arthritis patients to mediate cell hyperactivation and TNF-α secretion

OBJECTIVE

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease in which activated CD4+ T cells participate in the disease process by inducing inflammation. We aimed to investigate the role of Toll-like receptor 2 (TLR2) on CD4+ T cells in RA patients, and to elucidate the underlying mechanisms by which TLR2 contributes to the pathogenesis of RA.

METHODS

Serum samples were collected from RA patients and healthy controls. Soluble TLR2 levels were quantified using an enzyme-linked immunosorbent assay (ELISA). Flow cytometry was employed to assess the TLR2 expression level, activation status, cytokine production, reactive oxygen species (ROS) levels, and glucose uptake capacity of CD4+ T cells. Quantitative polymerase chain reaction (qPCR) was used to measure the expression of enzymes associated with glucose and lipid metabolism. The concentration of lactic acid in the culture supernatant was determined using a dedicated detection kit.

RESULTS

RA patients had higher levels of TLR2 in their serum, which positively correlated with C-reactive protein and rheumatoid factor. The expression level of TLR2 in CD4+ T cells of RA patients was increased, and TLR2+ cells showed higher activation levels than TLR2- cells. Activation of TLR2 in CD4+ T cells of RA patients promoted their activation, TNF-α secretion, and increased production of ROS. Furthermore, TLR2 activation led to changes in enzymes related to glucose metabolism, causing a shift in glucose metabolism towards the pentose phosphate pathway. Blocking oxidative phosphorylation and the pentose phosphate pathway had varying effects on CD4+ T cell function.

CONCLUSION

TLR2 reprograms the glucose metabolism of CD4+ T cells in RA patients, contributing to the development of RA through ROS-mediated cell hyperactivation and TNF-α secretion. Key Points • TLR2 is upregulated in CD4+ T cells of RA patients and correlates with disease severity markers such as CRP and RF. • Activation of TLR2 in CD4+ T cells promotes cell activation, TNF-α secretion, and increased ROS production, contributing to the pathogenesis of RA. • TLR2 activates glucose metabolism in CD4+ T cells, shifting towards the pentose phosphate pathway, which may be a novel therapeutic target for RA treatment. • Blocking glucose metabolism and ROS production can reduce CD4 + T cell hyperactivation and TNF-α secretion, indicating potential therapeutic strategies for RA management.

Identification of circulating autoantibodies to non-modified proteins associated with ACPA status in early rheumatoid arthritis

OBJECTIVE

The objective of this study was to discover autoantibodies to non-modified proteins associated with the presence/absence of ACPAs in RA.

METHODS

The autoantibody repertoire of 80 ACPA-negative and 80 ACPA-positive RA subjects from the Swedish population-based Epidemiological Investigation of RA (EIRA) cohort was screened using a suspension bead array built on protein fragments earlier described as autoimmunity targets. Four autoantibodies positive in the initial screening were validated in another set of EIRA samples containing 317 ACPA-positive, 302 ACPA-negative and 372 age- and sex-matched controls. The relationship between the four autoantibodies and lung abnormalities on high-resolution CT (HRCT) was examined in 93 early-RA patients from the LURA cohort. Association between the autoantibodies, smoking and MHC class II alleles was assessed by logistic regression analysis.

RESULTS

Anti-ANOS1 and anti-MURC IgG levels were associated with ACPA-positive status [odds ratio (OR) = 3.02; 95% CI 1.87-4.89; and OR = 1.86; 95% CI 1.16-2.97, respectively] and increased in ACPA-positive patients compared with controls. Anti-ANOS1 IgG was associated with smoking habit (OR = 2.11; 95% CI 1.22-3.69) and anti-MURC IgG with the presence of the MHC class II 'shared-epitope' genes (OR = 1.95; 95% CI 1.11-3.46). Anti-TSPYL4 IgG was associated with being ACPA negative (OR = 0.41; 95% CI 0.19-0.89). Anti-TSPYL4 IgG and anti-MAP2K6 IgG levels were increased in the ACPA-negative patients compared with controls. Presence of anti-MAP2K6 IgG and anti-TSPYL4 IgG correlated negatively with HRCT-defined lung abnormalities.

CONCLUSION

These four autoantibodies may be useful in diagnostics and in predicting clinical phenotypes of RA.

Advances in mRNA vaccine research in the field of quality control

In recent years, innovative research and development of mRNA vaccines have made remarkable achievements, especially in the context of pandemic infectious diseases such as the COVID-19 virus, and the need for rapid vaccine development has further fueled the rapid growth of this field. Nevertheless, there are still gaps in our understanding of the working mechanism of mRNA vaccines and their long-term safety, efficacy, and quality control. This article summarizes the development background and production process of mRNA vaccines, outlines existing reference guidelines, quality control projects, and testing methods at home and abroad, and also summarizes the difficulties and future prospects in research and development and quality control. It provides a reference for developing guidelines for mRNA vaccine production, quality control, and preclinical and clinical evaluation.

Monoamine oxidases: A missing link between mitochondria and inflammation in chronic diseases ?

The role of mitochondria spans from the regulation of the oxidative phosphorylation, cell metabolism and survival/death pathways to a more recently identified function in chronic inflammation. In stress situations, mitochondria release some pro-inflammatory mediators such as ATP, cardiolipin, reactive oxygen species (ROS) or mitochondrial DNA, that are believed to participate in chronic diseases and aging. These mitochondrial Damage-Associated Molecular Patterns (mito-DAMPs) can modulate specific receptors among which TLR9, NLRP3 and cGAS-STING, triggering immune cells activation and sterile inflammation. In order to counter the development of chronic diseases, a better understanding of the underlying mechanisms of low grade inflammation induced by mito-DAMPs is needed. In this context, monoamine oxidases (MAO), the mitochondrial enzymes that degrade catecholamines and serotonin, have recently emerged as potent regulators of chronic inflammation in obesity-related disorders, cardiac diseases, cancer, rheumatoid arthritis and pulmonary diseases. The role of these enzymes in inflammation embraces their action in both immune and non-immune cells, where they regulate monoamines levels and generate toxic ROS and aldehydes, as by-products of enzymatic reaction. Here, we discuss the more recent advances on the role and mechanisms of action of MAOs in chronic inflammatory diseases.

Propionibacterium freudenreichii MJ2-derived extracellular vesicles inhibit RANKL-induced osteoclastogenesis and improve collagen-induced rheumatoid arthritis

Rheumatoid arthritis causes excessive bone loss by stimulating osteoclast differentiation. Extracellular vesicles are valuable disease markers, conveyors of distant cell-to-cell communication, and carriers for drug delivery. The aim of this study was to investigate the anti-osteoclastogenic effects of extracellular vesicles derived from dairy Propionibacterium freudenreichii MJ2 (PFEVs) and the improvement effect of PFEVs on collagen-induced arthritis (CIA) animal model. PFEVs were observed by scanning electron microscopy, transmission electron microscopy, nanoparticle tracking analysis, and LC-MS/MS. The inhibitory activity of PFEVs against receptor activator of nuclear factor kappa-B ligand (RANKL)-induced osteoclast differentiation was investigated in RAW 264.7 cells. PFEVs significantly decreased the expression levels of genes and proteins related to osteoclast differentiation. PFEVs decreased RANK-RANKL binding. In a CIA mouse model, PFEVs treatment significantly reduced arthritis scores and collagen-specific immunoglobulins. PFEVs treatment also reduced pro-inflammatory cytokines and increased anti-inflammatory cytokines. The anti-inflammatory effects were confirmed by H&E staining, and PFEVs treatment inhibited osteoclastogenesis in the CIA mouse model. In conclusion, PFEVs inhibited osteoclast differentiation by inhibiting RANK-RANKL signaling, thereby decreasing the expression of osteoclast differentiation-related genes. PFEVs also improved collagen-induced arthritis by inhibiting inflammation and osteoclastogenesis.

The Causal Relationship between Immune-Mediated Inflammatory Diseases and Aortic Aneurysm: A Bidirectional Two-Sample Mendelian Randomization Study

Methods

We sourced genetic association data from public genome-wide association study databases for populations of European ancestry. Adhering to MR principles, we identified valid instrumental variables from genetic variants. A range of statistical methods were applied for MR analysis, with the inverse variance weighted (IVW) method emerging as the most reliable estimator of causality in this context.

Results

The causal estimates obtained using the IVW method revealed a significant association between genetically predicted AA and rheumatoid arthritis (RA; OR = 1.06, 95% CI = 1.01-1.12, P=0.029). Conversely, genetically predicted RA showed nonsignificant causal estimates of AA (OR = 0.97, 95% CI = 0.92-1.02, P=0.204). Additionally, there was no evidence to suggest that AA may increase the risk of inflammatory bowel disease (IBD), Crohn's disease (CD), ulcerative colitis (UC), systemic lupus erythematosus (SLE), and psoriasis (PSO). The sensitivity analysis confirmed the absence of heterogeneity or horizontal pleiotropy effects.

Conclusion

Our findings shed light on the causal effects between genetically predisposed AA and RA. They also suggest the potential clinical utility of human leukocyte antigen (HLA) risk genetic markers for developing personalized treatment and prevention strategies.

Lifetime Trauma Exposure and Arthritis in Older Adults

OBJECTIVE

Experiencing potentially traumatic events across one's lifecourse increases risk for poor physical health outcomes. Existing models emphasize the effects of any lifetime trauma exposure, risk accumulation (multiple traumas over time), and sensitive periods of exposure (specific exposure timepoints leading to lasting consequences). We examined how different indices of trauma exposure across the lifecourse were associated with later life arthritis, a common and debilitating health condition.

METHODS

Data include 5717 Health and Retirement Study participants (age mean [standard deviation] = 65.4 [12.9] years) who reported on lifetime adversity and trauma in 2006-2008. Lifetime trauma exposure was modeled as any trauma, accumulation of traumas, and lifecourse profiles (no exposure, childhood only, adulthood only, childhood and adulthood exposure). Outcomes included prevalent arthritis at baseline and incident arthritis across 12 years of follow-up. Covariate-adjusted generalized linear models for prevalence ratios and Cox proportional hazards models for hazard ratios were conducted.

RESULTS

Any lifetime trauma was associated with both prevalent arthritis at baseline (prevalence ratio = 1.13, 95% confidence interval = 1.05-1.22) and incident arthritis over 12 years (hazard ratio = 1.25, 95% confidence interval = 1.17-1.47). Greater trauma accumulation was significantly associated with both prevalent and incident arthritis. Childhood exposure was particularly strongly associated with prevalent and incident cases, with adulthood exposure being unassociated with incident arthritis. Across models, trauma exposure was associated with prevalent cases of both immune-related and osteoarthritis types.

CONCLUSIONS

Higher lifetime trauma burden, especially during childhood, may predispose individuals to arthritis later in life. Early intervention or prevention efforts should identify trauma as an important risk factor for musculoskeletal health across the lifecourse.

Longitudinal reciprocal association between rheumatoid arthritis and chronic obstructive pulmonary disease and mediation of inflammation

OBJECTIVES

To elucidate the longitudinal reciprocal association between RA and chronic obstructive pulmonary disease (COPD) and the mediating role of systemic inflammation in the association.

METHODS

A total of 403 045 participants from UK Biobank were enrolled in this study. A cross-lagged panel model was used to investigate the longitudinal reciprocal association between RA and COPD. Cox proportional hazards regression and logistic regression models were also conducted to examine the association between baseline RA and COPD during follow-up, and vice versa. Causal mediation analysis was then performed to explore the mediating roles of 160 systemic inflammatory biomarkers in the bidirectional association.

RESULTS

At baseline, 4755 (1.2%) and 6989 (1.7%) individuals were diagnosed with RA and COPD, respectively. After adjusting for the covariates, the result of a cross-lagged panel model revealed a bidirectional association between RA and COPD (β = 0.018, P < 0.001 for the RA→COPD path; β = 0.010, P < 0.001 for the COPD→RA path). In the non-COPD population, the risk of future COPD was increased in RA patients [Cox model: hazard ratio (HR) 1.65 (95% CI 1.50, 1.83); logistic model: odds ratio (OR) 1.85 (95% CI 1.66, 2.07)]. In the non-RA population, baseline COPD was associated with a higher risk of RA during follow-up [Cox model: HR 1.67 (95% CI 1.44, 1.92); logistic model: OR 1.70 (95% CI 1.47, 1.97)]. Five inflammatory factors mediated the RA→COPD path and CRP mediated the COPD→RA path (false discovery rate < 0.05).

CONCLUSIONS

A significant bidirectional association exists between RA and COPD and it is partially mediated by systemic inflammation.

Gingerol nanoparticles attenuate complete Freund adjuvant-induced arthritis in rats via targeting the RANKL/OPG signaling pathway

Rheumatoid arthritis (RA) is characterized by inflammatory joint pathology leading to the degradation of articular bone and cartilage, primarily triggered by synovial inflammation, resulting in joint discomfort. The metacarpophalangeal and proximal interphalangeal joints are predominantly affected. Treatment typically involves a combination of biological and synthetic disease-modifying antirheumatic drugs (DAMARDs) alongside steroid therapy. The application of nanomedicine has been instrumental in enhancing treatment efficacy by facilitating controlled release of pharmacologically active compounds, thus augmenting bioavailability and enabling targeted drug delivery. Gingerol, a constituent of ginger, possesses multifaceted properties. including anti-inflammatory, anti-oxidant, antidiabetic, and antipyretic effects. In this study, gingerol-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs), coated with chitosan, were administered orally to rats over a period of 21 days to address RA induced by complete Freund adjuvant (CFA). The rats were segregated into four experimental groups. Upon completion of the treatment regimen, blood samples were collected for the assessment of cyclooxygenase-2 (COX-2), RA factor, interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). Subsequent gene expression analysis was conducted to evaluate the levels of interleukin-4 (IL-4), interleukin-17a (IL-17a), IL-6, interferon-gamma (INF-γ), TNF-α, interleukin-1 beta (IL-1β), osteoprotegerin (OPG), and receptor activator of nuclear factor kappa-B ligand (RANKL). Statistical analyses utilizing one-way ANOVA followed by Tukey tests were applied to the data. The gene expression profiling revealed significant disparities in mRNA levels of IL-1β, IL-6, IL-4, IL-17a, RANKL, INF-γ, and TNF-α between the CFA-induced arthritis group and the control group. Consequently, it was inferred that gingerol-loaded PLGA NPs coated with chitosan exhibited heightened therapeutic efficacy in addressing CFA-induced arthritis in rats.

Unlocking the Future: New Biologic Therapies for Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disorder that leads to joint destruction and functional disability. Traditional treatments, including disease-modifying antirheumatic drugs (DMARDs), often fail, leaving many patients without remission. The advent of biologic therapies that target specific immune system components (e.g., cytokines, T cells) has transformed RA treatment by offering new management options. These biologics (e.g., TNF inhibitors, interleukin blockers) are highly effective in controlling disease activity and preventing joint destruction. However, their use comes with safety concerns, particularly regarding immunosuppression and infection risks. Although still experimental, studies predict that future research will focus on enhancing the clinical response and safety of these agents through personalized approaches or novel mechanisms of action.

Safety and efficacy of fecal microbiota transplantation (FMT) as a modern adjuvant therapy in various diseases and disorders: a comprehensive literature review

The human gastrointestinal (GI) tract microbiome is a complex and all-encompassing ecological system of trillions of microorganisms. It plays a vital role in digestion, disease prevention, and overall health. When this delicate balance is disrupted, it can lead to various health issues. Fecal microbiota transplantation (FMT) is an emerging therapeutic intervention used as an adjuvant therapy for many diseases, particularly those with dysbiosis as their underlying cause. Its goal is to restore this balance by transferring fecal material from healthy donors to the recipients. FMT has an impressive reported cure rate between 80% and 90% and has become a favored treatment for many diseases. While FMT may have generally mild to moderate transient adverse effects, rare severe complications underscore the importance of rigorous donor screening and standardized administration. FMT has enormous potential as a practical therapeutic approach; however, additional research is required to further determine its potential for clinical utilization, as well as its safety and efficiency in different patient populations. This comprehensive literature review offers increased confidence in the safety and effectiveness of FMT for several diseases affecting the intestines and other systems, including diabetes, obesity, inflammatory and autoimmune illness, and other conditions.

Gene therapy for polygenic or complex diseases

Gene therapy utilizes nucleic acid drugs to treat diseases, encompassing gene supplementation, gene replacement, gene silencing, and gene editing. It represents a distinct therapeutic approach from traditional medications and introduces novel strategies for genetic disorders. Over the past two decades, significant advancements have been made in the field of gene therapy, leading to the approval of various gene therapy drugs. Gene therapy was initially employed for treating genetic diseases and cancers, particularly monogenic conditions classified as orphan diseases due to their low prevalence rates; however, polygenic or complex diseases exhibit higher incidence rates within populations. Extensive research on the etiology of polygenic diseases has unveiled new therapeutic targets that offer fresh opportunities for their treatment. Building upon the progress achieved in gene therapy for monogenic diseases and cancers, extending its application to polygenic or complex diseases would enable targeting a broader range of patient populations. This review aims to discuss the strategies of gene therapy, methods of gene editing (mainly CRISPR-CAS9), and carriers utilized in gene therapy, and highlight the applications of gene therapy in polygenic or complex diseases focused on applications that have either entered clinical stages or are currently undergoing clinical trials.

The Effectiveness and Safety of Wu Tou Decoction on Rheumatoid Arthritis-A Systematic Review and Meta-Analysis

Rheumatoid arthritis (RA) is an autoimmune disease primarily affecting the joints and requires various treatments, including medication, injection, and physiotherapy. Wu tou decoction (WTD) is a traditional Chinese medicine prescribed for RA, with several articles documenting its effectiveness in RA treatment. This systematic review and meta-analysis aimed to evaluate the efficacy and safety of WTD for RA. We searched for randomized controlled trials (RCTs) comparing WTD with conventional treatments (including medication, injection, and physiotherapy) from its inception to May 2024. Primary outcomes were disease activity scores, including effective rate, tender joint count, and morning stiffness. Secondary outcomes comprised blood test results (erythrocyte sedimentation rate, C-reactive protein, and rheumatoid factor) and adverse events. Nineteen RCTs involving 1794 patients were included. Statistically, WTD demonstrated better improvement than conventional treatments (18 medications and 1 injection) across the effective rate, joint scale, and blood tests, regardless of the treatment type (monotherapy or combination therapy). Adverse events were reported in 11 studies, with no statistical differences observed between them. The numerical results showed that WTD may offer potential benefits for managing RA. However, the significant discrepancy between clinical practice and the low quality of the RCTs remains a limitation. Therefore, further well-designed studies with larger patient cohorts are needed to draw definitive conclusions.

hFcγRIIa: a double-edged sword in osteoclastogenesis and bone balance in transgenic mice

Rheumatoid arthritis (RA) is a chronic autoimmune disease accompanied by local and systemic bone loss. FcγRs, especially FcγRIIa (hFcγRIIa), have been implicated in the pathogenesis of RA. However, the contribution of hFcγRIIa to bone loss has not been fully elucidated. In the present study, we demonstrated the double-edged sword role of hFcγRIIa on osteoclast differentiation through investigations involving hFcγRIIa-transgenic (hFcγRIIa-Tg) mice. Our findings reveal that hFcγRIIa-Tg mice, previously shown to exhibit heightened susceptibility to collagen-induced arthritis (CIA), displayed increased osteoporosis during CIA or at advanced ages (40 weeks), accompanied by heightened in vivo osteoclast differentiation. Notably, bone marrow cells from hFcγRIIa-Tg mice exhibited enhanced efficiency in differentiating into osteoclasts and bone resorption in vitro compared to wild-type mice when stimulated with receptor activators of NF-κB ligand (RANKL). Additionally, hFcγRIIa-Tg mice exhibited augmented sensitivity to RANKL-induced bone loss in vivo, highlighting the osteoclast-promoting role of hFcγRIIa. Mechanistically, bone marrow cells from hFcγRIIa-Tg mice displayed heightened Syk self-activation, leading to mTOR-pS6 pathway activation, thereby promoting RANKL-driven osteoclast differentiation. Intriguingly, while hFcγRIIa crosslinking hindered RANKL-induced osteoclast differentiation, it activated the kinase cAbl, subsequently triggering STAT5 activation and inhibiting the expression of osteoclast-associated genes. This study provides novel insights into hFcγRIIa-mediated osteoclast biology, suggesting promising therapeutic targets for managing bone remodeling disorders.

Application of Injectable Hydrogels as Delivery Systems in Osteoarthritis and Rheumatoid Arthritis

Osteoarthritis and rheumatoid arthritis, though etiologically distinct, are both inflammatory joint diseases that cause progressive joint injury, chronic pain, and loss of function. Therefore, long-term treatment with a focus on relieving symptoms is needed. At present, the primary treatment for arthritis is drug therapy, both oral and intravenous. Although significant progress has been achieved for these treatment methods in alleviating symptoms, certain prominent drawbacks such as the substantial side effects and limited absorption of medications call for an urgent need for improved drug delivery methods. Injected hydrogels can be used as a delivery system to deliver drugs to the joint cavity in a controlled manner and continuously release them, thereby enhancing drug retention in the joint cavity to improve therapeutic effectiveness, which is attributed to the desirable attributes of the delivery system such as low immunogenicity, good biodegradability and biocompatibility. This review summarizes the types of injectable hydrogels and analyzes their applications as delivery systems in arthritis treatment. We also explored how hydrogels counteract inflammation, bone and cartilage degradation, and oxidative stress, while promoting joint cartilage regeneration in the treatment of osteoarthritis (OA) and rheumatoid arthritis (RA). This review also highlights new approaches to developing injectable hydrogels as delivery systems for OA and RA.

Cannabinoids in the Inflamed Synovium Can Be a Target for the Treatment of Rheumatic Diseases

The management of rheumatic diseases has noticeably changed in recent years with the development of targeted therapeutic agents, namely, biological disease-modifying antirheumatic drugs. Identifying essential signaling pathways and factors crucial for the development and progression of these diseases remains a significant challenge. Therapy could be used to delay the onset or reduce harm. The endocannabinoid system's presence within the synovium can be identified as a suggested target for therapeutic interventions due to its role in modulating pain, inflammation, and joint metabolism. This review brings together the most pertinent information concerning the actions of the endocannabinoid system present in inflamed synovial tissue and its interaction with phytocannabinoids and synthetic cannabinoids, which can be used from a therapeutic perspective to minimize the inflammatory and pain processes typical of osteoarthritis and rheumatoid arthritis.

Disease Activity, Inflammation Markers, and Quality of Life Are Associated with Muscle Strength in Croatian Rheumatoid Arthritis Patients-A National-Based Study

Background and Objectives: Rheumatoid arthritis (RA) patients experience sarcopenia and decreased muscle mass and handgrip strength, leading to decreased quality of life and disability. The prevalence of RA varies across regions. This study aimed to evaluate the factors associated with RA in Croatian regional centres and explore correlations between clinical parameters and muscle strength. Materials and Methods: Included in this study were 267 stable RA patients from four Croatian clinical centres. The patients' mean age was 60.4 ± 12.0 years, with 12.7% of them being male. For each study participant, information was gathered on their anthropometric characteristics, clinical and laboratory indicators, quality of life, disease activity, and sociodemographics. Results: The main results showed that in the female RA participants, the significant positive predictors are weight, height, exercise, VAS, and haemoglobin level. The negative predictors are the use of conventional synthetic disease-modifying anti-rheumatic drugs, the use of biological disease-modifying anti-rheumatic drugs, the number of tender joints, the number of swollen joints, the estimated sedimentation rate, the C-reactive protein, the disease activity score, the parameters of the EQ5D, and being prescribed with three or more medications. In the male RA participants, significant predictors of muscle strength are only weight, height, and anxiety/depression difficulties, according to the EQ5D. Conclusions: This study showed correlations between muscle strength and the parameters of disease activity, inflammation parameters, health-related quality of life, therapy, and exercise in the female RA participants in Croatia.

The association between the aggregate index of systemic inflammation and risk of rheumatoid arthritis: retrospective analysis of NHANES 1999-2018

Objective

The investigation purpose was to examine the correlation between the aggregate index of systemic inflammation (AISI) and rheumatoid arthritis (RA) by utilizing the NHANES database from the years 1999 to 2018.

Methods

The NHANES database was utilized to extract data spanning from 1999 to 2018. AISI, comprising neutrophils (NEU), monocytes (MONO), platelets (PLT), and lymphocytes (LYM), was computed based on counts. The identification of RA patients was accomplished through questionnaire data. To investigate the connection between AISI and RA, a weighted multivariate regression and subgroup analysis were conducted. In addition, restricted cubic splines (RCS) were employed for examining non-linear associations.

Results

The study encompassed a total of 41,986 patients, among whom 2,642 (6.29%) were diagnosed with RA. Upon controlling for all covariates, the outcomes of the multivariate logistic regression assay demonstrated a statistically significant association between higher Ln(AISI) levels and elevated odds of RA (odds ratio [OR]: 1.097; 95% confidence interval [CI]: 1.096-1.099, p < 0.001). The interaction test findings indicate that there is no statistically significant impact within this particular association. The results of the RCS regression model revealed a non-linear pattern in the correlation between Ln(AISI) and RA. The threshold level of AISI for RA was determined as 298.9. The risk of RA rises steeply when AISI surpasses the threshold value.

Conclusion

Overall, a positive association has been observed between AISI and RA. This study highlights the potential of AISI as an innovative, vital, and appropriate inflammatory biomarker for predicting the risk of developing rheumatoid arthritis in older individuals residing in the United States.

Antiarthritic and Antinociceptive Properties of Ylang-Ylang (Cananga odorata) Essential Oil in Experimental Models

The aim of this study was to evaluate the effect of ylang-ylang (Cananga odorata) essential oil (YEO) on models of experimental arthritis, persistent inflammation, and nociception in mice. YEO treatment at doses of 100 and 200 mg/kg reduced the infiltration of leukocytes into the joint cavities of mice submitted to zymosan-induced arthritis 6 h and 7 days after arthritis induction. At these doses, YEO treatment reduced the formation of joint edema 4 and 6 h after arthritis induction, and at a dose of 200 mg/kg, YEO treatment reduced mechanical hyperalgesia 3 and 4 h after arthritis induction. At the dose of 200 mg/kg, YEO treatment reduced interleukin-6 (IL-6) levels and cartilage destruction in the zymosan-induced arthritis model, and reduced edema formation and mechanical hyperalgesia in the model of persistent inflammation (21 days) induced by complete Freund's adjuvant (CFA) in mice. YEO treatment at a dose of 200 mg/kg reduced the nociceptive response in experimental models of nociception induced by acetic acid and formalin. The YEO treatment reduced inflammatory parameters in the experimental arthritis model, and presented antiarthritic, anti-hyperalgesic, antinociceptive, and anti-inflammatory properties.

Role and mechanism of IRF9 in promoting the progression of rheumatoid arthritis by regulating macrophage polarization via PSMA5

Aim

To explore the mechanisms of IRF9 in the progression of rheumatoid arthritis(RA), and the effects of IRF9 on M1/M2 polarization.

Methods

RA dataset (GSE55457) was downloaded from GEO. Correlation analysis between IRF9 and its downstream target protein PSMA5 was performed using bioinformatics analysis. The M1/M2 cell ratio of peripheral blood mononuclear cells which from 20 healthy specimen and 40 RA patients was determined. The expression of IRF9 and PSMA5 was detected using qPCR and Western blot. Then, knockdown IRF9 in RAW264.7 cell line (sh-IRF9 RAW264.7) was constructed. The effect of sh-IRF9 RAW264.7 on RA was explored by constructing a CIA mouse model.

Results

IRF9 is upregulated in RA and is of good early screening effect. The results of pathway analysis showed that IRF9 targets and regulates the PSMA5 signaling pathway. IRF9 and PSMA5 were significantly elevated in RA patients, M1/M2 ratio was also increased. The effects of IRF9 on RAW264.7 macrophages were deeply explored in vitro, revealing that knockdown of IRF9 suppressed PSMA5, M1/M2 ratio and the secretion of pro-inflammatory factor in RAW264.7. In mouse in vivo experiments, sh-IRF9 RAW264.7 cells were found to modulate RA by downregulating PSMA5, modulating the M1/M2 ratio through enhancing the anti-inflammatory factor, and suppressing the pro-inflammatory factor.

Conclusion

IRF9 promoted the progression of RA via regulating macrophage polarization through PSMA5.

Biological Clock Perspective in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by systemic polyarticular pain, and its main pathological features include inflammatory cell infiltration, synovial fibroblast proliferation, and cartilage erosion. Immune cells, synovial cells and neuroendocrine factors play pivotal roles in the pathophysiological mechanism underlying rheumatoid arthritis. Biological clock genes regulate immune cell functions, which is linked to rhythmic changes in arthritis pathology. Additionally, the interaction between biological clock genes and neuroendocrine factors is also involved in rhythmic changes in rheumatoid arthritis. This review provides an overview of the contributions of circadian rhythm genes to RA pathology, including their interaction with the immune system and their involvement in regulating the secretion and function of neuroendocrine factors. A molecular understanding of the role of the circadian rhythm in RA may offer insights for effective disease management.

PDIA3 orchestrates effector T cell program by serving as a chaperone to facilitate the non-canonical nuclear import of STAT1 and PKM2

Dysregulated T cell activation underpins the immunopathology of rheumatoid arthritis (RA), yet the machineries that orchestrate T cell effector program remain incompletely understood. Herein, we leveraged bulk and single-cell RNA sequencing data from RA patients and validated protein disulfide isomerase family A member 3 (PDIA3) as a potential therapeutic target. PDIA3 is remarkably upregulated in pathogenic CD4 T cells derived from RA patients and positively correlates with C-reactive protein level and disease activity score 28. Pharmacological inhibition or genetic ablation of PDIA3 alleviates RA-associated articular pathology and autoimmune responses. Mechanistically, T cell receptor signaling triggers intracellular calcium flux to activate NFAT1, a process that is further potentiated by Wnt5a under RA settings. Activated NFAT1 then directly binds to the Pdia3 promoter to enhance the expression of PDIA3, which complexes with STAT1 or PKM2 to facilitate their nuclear import for transcribing T helper 1 (Th1) and Th17 lineage-related genes, respectively. This non-canonical regulatory mechanism likely occurs under pathological conditions, as PDIA3 could only be highly induced following aberrant external stimuli. Together, our data support that targeting PDIA3 is a vital strategy to mitigate autoimmune diseases, such as RA, in clinical settings.

Therapeutic prospects of microRNAs derived from mesenchymal stem cell extracellular vesicles in rheumatoid arthritis: a comprehensive overview

Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by inflammatory joint damage. Recent studies have focused on the significance of microRNAs (miRNAs) in the pathogenesis of RA. Mesenchymal stem cells (MSCs) have emerged as a potential therapeutic option for RA based on their regenerative and immunomodulatory properties. MSCs release extracellular vesicles (EVs) containing miRNAs that can modulate immune and inflammatory responses. This article provides a comprehensive overview of the current evidence on the existence of various MSCs-derived miRNAs involved in the pathophysiology, characterization, and treatment of RA. An overview of the miRNA profiles in MSC-EVs is provided, along with an examination of their impact on various cell types implicated in RA pathogenesis, including synovial fibroblasts, macrophages, and T cells. Furthermore, the therapeutic capability of MSC-EVs for miRNA-based therapies in RA is discussed. In total, this review can present an extensive view of the complex interaction between EVs and MSC-derived miRNAs in RA and thus suggest valuable strategies for developing new therapeutic approaches to target this debilitating disease.

Single nucleotide polymorphisms in the cannabinoid CB2 receptor: Molecular pharmacology and disease associations

Preclinical evidence implicating cannabinoid receptor 2 (CB2) in various diseases has led researchers to question whether CB2 genetics influence aetiology or progression. Associations between conditions and genetic loci are often studied via single nucleotide polymorphism (SNP) prevalence in case versus control populations. In the CNR2 coding exon, ~36 SNPs have high overall population prevalence (minor allele frequencies [MAF] ~37%), including non-synonymous SNP (ns-SNP) rs2501432 encoding CB2 63Q/R. Interspersed are ~27 lower frequency SNPs, four being ns-SNPs. CNR2 introns also harbour numerous SNPs. This review summarises CB2 ns-SNP molecular pharmacology and evaluates evidence from ~70 studies investigating CB2 genetic variants with proposed linkage to disease. Although CNR2 genetic variation has been associated with a wide variety of conditions, including osteoporosis, immune-related disorders, and mental illnesses, further work is required to robustly validate CNR2 disease links and clarify specific mechanisms linking CNR2 genetic variation to disease pathophysiology and potential drug responses.

Mesenchymal stem cells in autoimmune disease: A systematic review and meta-analysis of pre-clinical studies

Mesenchymal Stem Cells (MSCs) are of interest in the clinic because of their immunomodulation capabilities, capacity to act upstream of inflammation, and ability to sense metabolic environments. In standard physiologic conditions, they play a role in maintaining the homeostasis of tissues and organs; however, there is evidence that they can contribute to some autoimmune diseases. Gaining a deeper understanding of the factors that transition MSCs from their physiological function to a pathological role in their native environment, and elucidating mechanisms that reduce their therapeutic relevance in regenerative medicine, is essential. We conducted a Systematic Review and Meta-Analysis of human MSCs in preclinical studies of autoimmune disease, evaluating 60 studies that included 845 patient samples and 571 control samples. MSCs from any tissue source were included, and the study was limited to four autoimmune diseases: multiple sclerosis, rheumatoid arthritis, systemic sclerosis, and lupus. We developed a novel Risk of Bias tool to determine study quality for in vitro studies. Using the International Society for Cell & Gene Therapy's criteria to define an MSC, most studies reported no difference in morphology, adhesion, cell surface markers, or differentiation into bone, fat, or cartilage when comparing control and autoimmune MSCs. However, there were reported differences in proliferation. Additionally, 308 biomolecules were differentially expressed, and the abilities to migrate, invade, and form capillaries were decreased. The findings from this study could help to explain the pathogenic mechanisms of autoimmune disease and potentially lead to improved MSC-based therapeutic applications.

Low-Dose Radiotherapy Attenuates Experimental Autoimmune Arthritis by Inducing Apoptosis of Lymphocytes and Fibroblast-Like Synoviocytes

Low-dose radiotherapy (LDRT) has been explored as a treatment option for various inflammatory diseases; however, its application in the context of rheumatoid arthritis (RA) is lacking. This study aimed to elucidate the mechanism underlying LDRT-based treatment for RA and standardize it. LDRT reduced the total numbers of immune cells, but increased the apoptotic CD4+ T and B220+ B cells, in the draining lymph nodes of collagen induced arthritis and K/BxN models. In addition, it significantly reduced the severity of various pathological manifestations, including bone destruction, cartilage erosion, and swelling of hind limb ankle. Post-LDRT, the proportion of apoptotic CD4+ T and CD19+ B cells increased significantly in the PBMCs derived from human patients with RA. LDRT showed a similar effect in fibroblast-like synoviocytes as well. In conclusion, we report that LDRT induces apoptosis in immune cells and fibro-blast-like synoviocytes, contributing to attenuation of arthritis.