The interplay between inflammation and metabolism in rheumatoid arthritis

Enzymatic depletion of circulating glutamine is immunosuppressive in cancers

Although glutamine addiction in cancer cells is extensively reported, there is controversy on the impact of glutamine metabolism on the immune cells within the tumor microenvironment (TME). To address the role of extracellular glutamine, we enzymatically depleted circulating glutamine using PEGylated Helicobacter pylori gamma-glutamyl transferase (PEG-GGT) in syngeneic mouse models of breast and colon cancers. PEG-GGT treatment inhibits growth of cancer cells in vitro, but in vivo it increases myeloid-derived suppressor cells (MDSCs) and has no significant impact on tumor growth. By deriving a glutamine depletion signature, we analyze diverse human cancers within the TCGA and illustrate that glutamine depletion is not associated with favorable clinical outcomes and correlates with accumulation of MDSC. Broadly, our results help clarify the integrated impact of glutamine depletion within the TME and advance PEG-GGT as an enzymatic tool for the systemic and selective depletion (no asparaginase activity) of circulating glutamine in live animals.

Immuno-metabolic reprogramming of T cell: a new frontier for pharmacotherapy of Rheumatoid arthritis

Rheumatoid arthritis (RA) is a persistent autoimmune condition characterized by ongoing inflammation primarily affecting the synovial joint. This inflammation typically arises from an increase in immune cells such as neutrophils, macrophages, and T cells (TC). TC is recognized as a major player in RA pathogenesis. The involvement of HLA-DRB1 and PTPN-2 among RA patients confirms the TC involvement in RA. Metabolism of TC is maintained by various other factors like cytokines, mitochondrial proteins & other metabolites. Different TC subtypes utilize different metabolic pathways like glycolysis, oxidative phosphorylation and fatty acid oxidation for their activation from naive TC (T0). Although all subsets of TC are not deleterious for synovium, some subsets of TC are involved in joint repair using their anti-inflammatory properties. Hence artificially reprogramming of TC subset by interfering with their metabolic status poised a hope in future to design new molecules against RA.

IGF2BP2 regulates the inflammation of fibroblast-like synoviocytes via GSTM5 in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease with an unknown etiology. RA cannot be fully cured and requires lengthy treatment, imposing a significant burden on both individuals and society. Due to the lack of specific drugs available for treating RA, exploring a key new therapeutic target for RA is currently an important task. Activated fibroblast-like synoviocytes (FLSs) play a crucial role in the progression of RA, which release interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α resulting in abnormal inflammatory reaction in the synovium. A previous study has highlighted the correlation of m6A reader insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) with inflammation-related diseases in human. However, the role of IGF2BP2 in the inflammatory reaction of FLSs during RA progression has not been assessed. In this study, IGF2BP2 expression was decreased in the synovial tissues of RA patients and collagen-induced arthritis (CIA) rats. Intra-articular injection of an adeno-associated virus (AAV) vector overexpressing IGF2BP2 relieved paw swelling, synovial hyperplasia and cartilage destruction in CIA rats. IGF2BP2 overexpression also inhibited lipopolysaccharide (LPS)-mediated RA fibroblast-like synoviocytes (RA-FLSs) migration and invasion accompanied by a decreased level of inflammatory factors in vitro. Conversely, IGF2BP2 suppression promoted RA-FLSs migration and invasion with an elevated level of inflammatory factors in vitro. The sequencing result showed that glutathione S-transferase Mu 5 (GSTM5), a key antioxidant gene, was the target mRNA of IGF2BP2. Further experiments demonstrated that IGF2BP2 strengthened the stability of GSTM5 mRNA, leading to weakened inflammatory reaction and reduced expression of matrix metalloproteinase 9 and 13 (MMP9, MMP13). Therefore, IGF2BP2-GSTM5 axis may represent a potential therapeutic target for RA treatment.

Laboratory features of effects of peloidotherapy and aromatherapy in patients with rheumatoid arthritis

Peloidotherapy and aromatherapy have been used for years in the treatment of numerous inflammatory conditions, including rheumatoid arthritis (RA). The exact mechanism of their action in RA is unclear. The goal of our research is to determine the effect of peloidotherapy and aromatherapy on inflammation parameters in RA patients. Our study included 20 patients of both sexes, with confirmed diagnosis of RA, older than 18 years. Patients were treated during 28 days with combination of peloidotherapy and aromatherapy. Serum samples for detection of levels of inflammation parameters were taken at two intervals: before the start of therapy and at the end of treatment. The results of our study show that there were no significant changes in the parameters of the complete blood count. Nevertheless, a statistically significant decrease in the serum concentration of two markers of inflammation-interleukin-6 (IL-6) and nitrogen-oxide (NO)-was detected. Correlation analyses results say that there is a synchronized drop in the serum concentrations of CRP and the sedimentation rate, and the serum concentrations of fibrinogen and IL-6 are in the same relationship as well as serum levels of IL-6 and NO. Bearing in mind the importance of IL-6 and NO in the pathogenesis of inflammation in RA, we conclude that the application of our therapeutic protocol can be a significant add-on treatment to classic immunomodulators. Due to the small number of study participants, the lack of a control group, and the short follow-up time of patients, additional research is needed.

Unveiling the Nexus: Cellular Metabolomics Unravels the Impact of Estrogen on Nicotinamide Metabolism in Mitigating Rheumatoid Arthritis Pathogenesis

Rheumatoid arthritis (RA) is a metabolic joint disorder influenced by hormonal regulation, notably estrogen, which plays a cytoprotective role against inflammation. While estrogen's impact on RA pathogenesis has been studied, the altered metabolite expression under estrogen's influence remains unexplored. This study investigated the changes in the metabolome of synovial fibroblasts isolated from RA patients under 17β-estradiol (E2) using the liquid chromatography with tandem mass spectrometry (LC-MS/MS) approach followed by multivariate and biological pathway analysis along with in vitro validation. Results identified 3624 m/z, among which eight metabolites were significant (p < 0.05). Nicotinate and nicotinamide metabolism was found to be highly correlated with the treatment of E2, with metabolites NAD+ and 1-methynicotinamide (1-MNA) upregulated by E2 induction in RA-FLS. PharmMapper analysis identified potential gene targets of 1-MNA, which were further matched with RA gene targets, and thus, STAT1, MAPK14, MMP3, and MMP9 were concluded to be the common targets. E2 treatment affected the expression of these gene targets and ameliorated the development of oxidative stress associated with RA inflammation, which can be attributed to increased concentration of 1-MNA. Thus, an LC-MS/MS-based metabolomics study revealed the prominent role of estrogen in preventing inflammatory progression in RA by altering metabolite concentration, which can support its therapeutic capacity in remitting RA.

Higher Risk of Rheumatoid Arthritis in Patients With Chronic Rhinosinusitis: Prospective Association in the U.K. Biobank and Genetic Evidence by Mendelian Randomization Analysis

BACKGROUND

Previous studies have shown that respiratory diseases are associated with an increased risk of rheumatoid arthritis (RA). However, whether there is a correlation between chronic rhinosinusitis (CRS) and RA is not known. Due to the high incidence of CRS, it remains to be clarified whether we should pay additional attention to RA risk in the huge population of CRS.

METHODS

We used a 2-sample Mendelian randomization (MR) analysis to explore the causal effects of CRS on the incidence of RA. The inverse variance weighted (IVW) approach was used as the main analysis in the MR randomization study. Then, we used the data from the U.K. Biobank to examine the association between RA and CRS at the individual level in a prospective cohort. We identified patients with CRS at the time of recruitment and further followed the incidence of RA until 2021. The risk of developing RA in patients with CRS was determined by a multivariate Cox regression model. We used 3 multivariate Cox models to adjust for individual characteristics, lifestyle factors and concomitant diseases, respectively.

RESULTS

The MR analysis by the IVW model suggested that the odds ratio of RA associated with genetically predicted CRS was 2.39 (95% CI [1.08-5.30]; p  =  .032). In the first multivariate model adjusting for individual characteristics, CRS was associated with a 47% increase of risk of developing RA (hazard ratio [HR]  =  1.47; 95% CI [1.12-1.90]). In the second multivariate model adjusting for lifestyle factors, the HR of RA associated with CRS was 1.48 (95% CI [1.15-1.90]). In the third multivariate model, chronic sinusitis was associated with a 32% increase in RA risk (HR  =  1.32; 95% CI [1.03-1.70]).

CONCLUSION

CRS has a genetically causal effect on the incidence of RA, and the risk of RA is greatly higher in CRS at the individual level. This is the first study to reveal an association between CRS and RA. Due to the high incidence of CRS, it is recommended that additional attention should be paid to the increased RA risk in patients with CRS compared to that in common people.

Periplogenin inhibits pathologic synovial proliferation and infiltration in rheumatoid arthritis by regulating the JAK2/3-STAT3 pathway

Rheumatoid arthritis (RA) is an autoimmune disease that affects joints, causing inflammation, synovitis, and erosion of cartilage and bone. Periplogenin is an active ingredient in the anti-rheumatic and anti-inflammatory herb, cortex periplocae. We conducted a study using a CIA model and an in vitro model of fibroblast-like synoviocytes (FLS) induced by Tumor Necrosis Factor-alpha (TNF-α) stimulation. We evaluated cell activity, proliferation, and migration using the CCK8 test, EDU kit, and transwell assays, as well as network pharmacokinetic analysis of periplogenin targets and RA-related effects. Furthermore, we measured inflammatory factors and matrix metalloproteinases (MMPs) expression using ELISA and qRT-PCR assays. We also evaluated joint destruction using HE and Safranin O-Fast Green Staining and examined the changes in the JAK2/3-STAT3 pathway using western blot. The results indicated that periplogenin can effectively inhibit the secretion of inflammatory factors, suppress the JAK2/3-STAT3 pathway, and impede the proliferation and migration of RA FLS. Thus, periplogenin alleviated the Synovial inflammatory infiltration of RA.

Effect of basal metabolic rate on rheumatoid arthritis: a Mendelian randomization study

PURPOSE

Basal metabolic rate (BMR) as one of the most basic and significant indicators of metabolism has been associated with human health. Previous studies showed that the development of rheumatoid arthritis (RA) is linked to BMR; however, the causal relationship between BMR and RA is unknown. Thus, we aimed to explore the causal relationship between BMR and RA as well as RA-related factors.

METHODS

Mendelian randomization (MR) analysis was performed on collected genome-wide association studies information. The effect of horizontal pleiotropy was detected by MR-PRESSO and MR-Radial. Five MR analysis methods were applied, including inverse variance weighted, MR-Egger, weighted median, weighted mode, and simple mode. Four sensitivity analysis methods were used for the validation of the significant MR analysis results. A two-component mixture of regressions method was additionally used to validate single nucleotide polymorphisms and to verify results.

RESULTS

Genetically, there is a causal effect of BMR on overall RA (odds ratio = 1.25, 95% confidence interval: 1.07-1.47, PIVW = .006), seropositive RA (odds ratio = 1.20, 95% confidence interval: 1.01-1.44, PIVW = .035), and seronegative RA (odds ratio = 1.36, 95% confidence interval: 1.04-1.78, PIVW = .023). Sensitivity analyses validated the robustness of the above associations. No evidence supported the effect of RA on BMR. Moreover, BMR showed no causal relationship with rheumatoid factor, C-reactive protein, erythrocyte sedimentation rate, interleukin-1β, tumor necrosis factor-α, and matrix metallopeptidase 3.

CONCLUSION

MR results implied the causal effect of BMR on RA and raised our attention to the importance of BMR in RA's pathology.

Prevalence and Comorbidities Among Individuals With Rheumatoid Arthritis in the Saudi Arabian Context

BACKGROUND

 Rheumatoid arthritis (RA) in Saudi Arabia (SA) is a significant health concern with a notable impact on individuals and the healthcare system. This study aimed to investigate the prevalence and profile of comorbidities in patients with RA.

METHODOLOGY

 This is a retrospective descriptive study involving 150 RA patients from August 2022 to August 2023, which was conducted at Khamis Mushait General Hospital, a major healthcare institution in SA. We examined the medical records to gather pertinent information. Stata Statistical Software: Release 18 (2023; StataCorp LLC, College Station, Texas, United States) was used for data analysis. The examination focused on sociodemographic factors, disease duration, prescribed medications (including methotrexate and biologic therapy), and the presence of comorbidities. Approval for the study was obtained from the Institutional Review Board of the Aseer Ministry of Health (approval number: H-06-B-091).

RESULTS

 The study found a high prevalence of comorbidities in patients with RA. Around 96.7% of the patients had at least one documented comorbidity, highlighting this population's burden of additional health conditions. The most common comorbidity observed was anemia, affecting 48.7% of the patients. Other frequently observed comorbidities include hypertension, hyperlipidemia, diabetes mellitus, osteoporosis, interstitial lung disease, chronic renal disease, stroke, and coronary artery disease. The factors influencing comorbidities included an odds ratio of 1.086 (p=0.025), while being male was associated with lower odds (odds ratio=0.529, p=0.017). Additionally, disease duration (odds ratio=1.164, p=0.007), methotrexate use (odds ratio=2.553, p=0.001), and receiving biologic therapy (odds ratio=3.488, p<0.001) were significant contributors to comorbidities.

CONCLUSION

 These findings highlight the need for comprehensive approaches to address RA and its associated comorbidities. Research and awareness initiatives are essential to understand better the specific nuances of RA in SA, leading to improved diagnostic and treatment strategies for the needs of the local population.

Effects of Soy Bread on Cardiovascular Risk Factor, Inflammation and Oxidative Stress in Women With Active Rheumatoid Arthritis: A Randomized Double-Blind Controlled Trial

Rheumatoid arthritis (RA) is a systemic inflammatory autoimmune disorder with widespread synovitis. Isoflavones, the main active component of soy, have been reported to have potent anti-inflammatory effects; the previous RA animal models showed the promising effect of soy supplementation. We aimed to evaluate the effect of soy bread on inflammatory markers and lipid profiles in RA patients. The present study was designed as a randomized controlled trial. RA patients were randomly allocated to obtain soy bread (n = 22) or placebo bread (n = 22) for 8 weeks. Fasting serum levels of lipid profile, total antioxidant capacity (TAC), tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), and DAS28 were checked. Findings showed that there were no significant differences between the two groups in physical activity and dietary intake at the beginning of the study and the end of the study. There were no significant differences between the two groups in measured lipid profile markers, including high-density lipoprotein, low-density lipoprotein, total cholesterol, triglyceride, and very low-density lipoprotein, at the end of the trial. In addition, TAC and CRP also were not significant at the end of the trial between the 2 groups (0.66 and 0.12, respectively). However, the serum levels of TNF-α reduced significantly in the soy bread group at the end of the intervention (p < 0.000) and compared with the control group (p < 0.019). Soy bread consumption only decreased circulating TNF-α serum concentration. Other outcome measures were not changed following supplementation. Future long-term, well-designed studies are needed to confirm these findings.

Trial Registration

Iranian Registry of Clinical Trials Identifier: IRCT20181021041396N1.

A stronger association of depression with rheumatoid arthritis in presence of obesity and hypertriglyceridemia

Background

Rheumatoid arthritis (RA) is an autoimmune disorder characterized by chronic and systemic inflammation. Recent research underscores the role of chronic inflammation in multiple common RA comorbidities such as depression, obesity, and cardiovascular diseases (CVDs), suggesting a potential overlap of the pathogenic mechanisms for RA. However, it is not well understood how the coexistence of these comorbid conditions impacts the risk of RA and whether any such association relates to body's inflammatory state.

Methods

We used data from the 2007-2010 United States National Health and Nutrition Examination Survey (NHANES) database and compared RA prevalence between subsamples with the presence of any two conditions among depression, obesity, and hypertriglyceridemia (HTG). Each subsample was further divided into three categories based on the serum level of the inflammatory marker C-reactive protein (CRP) and analyzed for statistically significant differences using three-way χ2 tests of independence.

Results

The study was conducted on 4,136 patients who fulfilled the inclusion criteria (representing 163,540,241 individuals after adjustment for sampling weights). Rates of depression, obesity, and HTG were found to be significantly higher (P < 0.001) among the subjects with RA compared with the control population with no arthritis. The presence of depression along with obesity or HTG showed a noticeably higher RA prevalence but such an association was not observed for the combination of obesity and HTG. The synergistic effect of HTG with depression was found to be most prominent at a medium CRP level (1-3 mg/L), while for obesity, the effect was observed across all CRP levels examined. These findings were further confirmed by the three-way χ2 test for independence.

Conclusions

The presence of obesity or HTG in subjects suffering from depression might pose an increased risk of RA. Inflammatory mechanisms potentially play an important underlying role as suggested by the strong dependency of the association to CRP level. Identification of synergistic associations between RA risk conditions could provide useful information to predict the development and progress of RA.

A diagnostic electrochemical aptasensor development for sCD80 protein detection in human serum

Elevating soluble CD80 (sCD80) in human serum is a natural response to autoimmune diseases such as rheumatoid arthritis (RA). The level of sCD80 is associated with RA development and prognosis; therefore, it is potentially used as a biomarker. sCD80 is commonly measured in human serum using immunoassays (e.g., ELISA) with multiple drawbacks, mainly cross-reactivity. Aptamer-based biosensors (aptasensors) development for quantifying and detecting different biological molecules demonstrates applicability in next-generation medicine and biomarker detection. Herein, we selected a specific aptamer for sCD80 by conventional in-vitro selection process (SELEX) with the high-affinity aptamer (Kd = 47.69 nM). A sensitive aptasensor, for the first time, was developed on a screen-printed gold electrode (AuSPE) platform compatible with easy-to-use label-free electrochemical impedance spectroscopy. The immobilization of the aptamer on the gold surface and the presence of sCD80 in a complex with the aptamer were characterized by photo-induced force microscopy, which revealed the uniform assembly of the aptamer monolayer and the distribution of sCD80 on the electrode surface. The developed aptasensor showed a linear performance (0.025-10.0 nM of protein) with a detection limit of 8.0 pM. Furthermore, the aptasensor was tested in a biological matrix, where a linear signal was observed for the increased amount of spiked sCD80 (R2 = 0.9887). The recovery of the spiked amounts ranged from 105 to 125% with coefficient of variation (CV%) <7%, which supported the applicability of this sensor in detecting sCD80 for diagnosis.

Therapeutic potential of natural products in inflammation: underlying molecular mechanisms, clinical outcomes, technological advances, and future perspectives

Chronic inflammation is a common underlying factor in many major diseases, including heart disease, diabetes, cancer, and autoimmune disorders, and is responsible for up to 60% of all deaths worldwide. Metformin, statins, and corticosteroids, and NSAIDs (non-steroidal anti-inflammatory drugs) are often given as anti-inflammatory pharmaceuticals, however, often have even more debilitating side effects than the illness itself. The natural product-based therapy of inflammation-related diseases has no adverse effects and good beneficial results compared to substitute conventional anti-inflammatory medications. In this review article, we provide a concise overview of present pharmacological treatments, the pathophysiology of inflammation, and the signaling pathways that underlie it. In addition, we focus on the most promising natural products identified as potential anti-inflammatory therapeutic agents. Moreover, preclinical studies and clinical trials evaluating the efficacy of natural products as anti-inflammatory therapeutic agents and their pragmatic applications with promising outcomes are reviewed. In addition, the safety, side effects and technical barriers of natural products are discussed. Furthermore, we also summarized the latest technological advances in the discovery and scientific development of natural products-based medicine.

Mass spectrometry-based metabolic profiling for identification of biomarkers related to footpad dermatitis in ducks

1. A new assessment method for duck footpad dermatitis (FPD) evaluation was developed, combining visual and histological characters using the images and sections of 400 ducks' feet at 340 d of age. All ducks were graded as G0 (healthy), G1 (mild), G2 (moderate) and G3 (severe) according to the degree of FPD.2. To reveal the potential biomarkers in serum related to duck FPD, non-targeted metabolomics and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were used to explore differential metabolites in each group.3. There were 57, 91 and 210 annotated differential metabolites in groups G1, G2 and G3 compared with G0, which meant that the severity of FPD increased in line with the number of metabolites. Four metabolites, L-phenylalanine, L-arginine, L-leucine and L-lysine, were considered potential biomarkers related to FPD.4. KEGG enrichment analysis showed that the FPD was mainly involved in glycolysis, the tricarboxylic acid (TCA) cycle, the pentose phosphate pathway and amino acid metabolism. These are related to production metabolism and can affect the physiological activities of ducks, which might explain the decrease in production performance.

Apoptosis Regulation in Osteoarthritis and the Influence of Lipid Interactions

Osteoarthritis (OA) is one of the most common chronic diseases in human and animal joints. The joints undergo several morphological and histological changes during the development of radiographically visible osteoarthritis. The most discussed changes include synovial inflammation, the massive destruction of articular cartilage and ongoing joint destruction accompanied by massive joint pain in the later stadium. Either the increased apoptosis of chondrocytes or the insufficient apoptosis of inflammatory macrophages and synovial fibroblasts are likely to underly this process. In this review, we discuss the current state of research on the pathogenesis of OA with special regard to the involvement of apoptosis.

Lipid oxidation dysregulation: an emerging player in the pathophysiology of sepsis

Sepsis is a life-threatening organ dysfunction caused by abnormal host response to infection. Millions of people are affected annually worldwide. Derangement of the inflammatory response is crucial in sepsis pathogenesis. However, metabolic, coagulation, and thermoregulatory alterations also occur in patients with sepsis. Fatty acid mobilization and oxidation changes may assume the role of a protagonist in sepsis pathogenesis. Lipid oxidation and free fatty acids (FFAs) are potentially valuable markers for sepsis diagnosis and prognosis. Herein, we discuss inflammatory and metabolic dysfunction during sepsis, focusing on fatty acid oxidation (FAO) alterations in the liver and muscle (skeletal and cardiac) and their implications in sepsis development.

Reframing the link between metabolism and NLRP3 inflammasome: therapeutic opportunities

Inflammasomes are multiprotein signaling platforms in the cytosol that senses exogenous and endogenous danger signals and respond with the maturation and secretion of IL-1β and IL-18 and pyroptosis to induce inflammation and protect the host. The inflammasome best studied is the Nucleotide-binding oligomerization domain, leucine-rich repeat-containing family pyrin domain containing 3 (NLRP3) inflammasome. It is activated in a two-step process: the priming and the activation, leading to sensor NLRP3 oligomerization and recruitment of both adaptor ASC and executioner pro-caspase 1, which is activated by cleavage. Moreover, NLRP3 inflammasome activation is regulated by posttranslational modifications, including ubiquitination/deubiquitination, phosphorylation/dephosphorylation, acetylation/deacetylation, SUMOylation and nitrosylation, and interaction with NLPR3 protein binding partners. Moreover, the connection between it and metabolism is receiving increasing attention in this field. In this review, we present the structure, functions, activation, and regulation of NLRP3, with special emphasis on regulation by mitochondrial dysfunction-mtROS production and metabolic signals, i.e., metabolites as well as enzymes. By understanding the regulation of NLRP3 inflammasome activation, specific inhibitors can be rationally designed for the treatment and prevention of various immune- or metabolic-based diseases. Lastly, we review current NLRP3 inflammasome inhibitors and their mechanism of action.

Decipher the pharmacological mechanisms of raw and wine-processed Curculigo orchioides Gaertn. on bone destruction in rheumatoid arthritis rats using metabolomics

ETHNOPHARMACOLOGICAL RELEVANCE

Curculigo orchioides Gaertn. (CO), a traditional Chinese herb recorded in Chinese Pharmacopoeia, can nourish kidney yang, strengthen bones, and dispell cold-dampness. Raw CO (rCO) and wine-processed CO (pCO), the main processed products of CO for clinical application, show differences in nourishing kidney yang and ameliorate osteoporosis. However, the difference in efficacy and mechanism of rCO and pCO on bone destruction in rheumatoid arthritis (RA) remain unclear.

AIM OF THE STUDY

To compare the pharmacodynamics of rCO and pCO in the treatment of bone destruction in RA and to reveal the potential mechanism by which rCO and pCO exert effects by metabolomics approach.

MATERIALS AND METHODS

Ultra-high performance liquid chromatography Q exactive mass spectrometry (UHPLC-Q-Exactive-MS) combined with multivariate data analysis was applied to identify the differential chemical components in rCO and pCO. Collagen-induced arthritis (CIA) rats were orally administrated with different doses of rCO and pCO for 4 weeks. The body weight, paw swelling, arthritis scores, serum inflammatory cytokines concentration, knee tumor necrosis factor (TNF)-α, interleukin (IL)-6 protein levels, and inflammatory cell infiltration were determined to investigate the effects of rCO and pCO on arthritic symptoms and inflammatory responses in CIA rats. The effects of rCO and pCO on bone destruction were assessed using safranin O-fast green and tartrate-resistant acid phosphatase (TRAP) staining, immunohistochemical analysis of osteoprotegerin (OPG) and receptor activator of nuclear factor-κB ligand (RANKL) proteins, and micro-computed tomography (micro-CT) in rats. In addition, metabolomics was performed to explore the mechanism of rCO and pCO against bone destruction in RA.

RESULTS

A total of 41 chemical constituents were identified in both rCO and pCO, 9 of which were screened out as discriminatory compounds. According to the pharmacodynamic assays, pCO exhibited a stronger effect than rCO in attenuating the severity of arthritis, reducing inflammation, and inhibiting bone destruction. The metabolomics results showed that pentose phosphate pathway was the key metabolic pathways regulated by rCO, while pCO regulated multiple metabolic pathways including phenylalanine metabolism pathways, phenylalanine, tyrosine and tryptophan biosynthesis, taurine and hypotaurine metabolism, and glycerophospholipid metabolism pathways.

CONCLUSION

pCO displayed a better effect on alleviating bone destruction in RA was than rCO. This might be associated with that pCO can decrease inflammation in RA through regulating more metabolism pathways.

Associations between rheumatoid arthritis, incident heart failure, and left ventricular ejection fraction

BACKGROUND

Rheumatoid arthritis (RA) is an independent risk factor for heart failure (HF). Yet, the association between RA and left ventricular ejection fraction (LVEF) in incident HF is not well studied, nor are outcomes of HF in RA by LVEF.

METHODS

We identified incident HF patients between 2003 and 2018 through the Swedish Heart Failure Registry, enriched with data from national health registers. Using logistic regression, associations between a prior diagnosis of RA and LVEF among HF patients and vs age, sex, and geographical area matched general population controls without HF were assessed. Additionally, associations between HF with vs without a prior diagnosis of RA, by LVEF, and outcomes up to 5 years after HF diagnosis were investigated using Cox regression. LVEF was primarily dichotomized at 40% and secondarily categorized as <40%, 40% to 49%, and ≥50%. Covariates included demographics and cardiovascular comorbidities.

RESULTS

Among 20,916 incident HF patients, 331 (1.6%) had RA vs 1,047/103,501 (1.0%) of HF-free controls. The odds ratio (OR) for RA was 1.4 (95% CI: 1.1-1.8) in LVEF<40% vs HF-free controls and 1.6 (95% CI: 1.3-2.0) in LVEF≥40% vs HF-free controls. Among HF patients, RA was more common in HF with LVEF ≥40% (1.9%) vs LVEF<40% (1.3%), corresponding to OR 1.4 (95% CI: 1.1-1.7). No associations between RA and cardiovascular outcomes were observed across LVEF. An association between RA and all-cause mortality was observed only for patients with LVEF<40% (hazard ratio: 1.4; 95% CI: 1.1-1.8).

CONCLUSIONS

RA was independently associated with incident HF, particularly HF with LVEF≥40%. RA did not associate with cardiovascular outcomes following HF diagnosis but was associated with increased risk of all-cause mortality in HF with LVEF<40%.

Integrated Omic Analysis of Human Plasma Metabolites and Microbiota in a Hypertension Cohort

Hypertension is closely related to metabolic dysregulation, which is associated with microbial dysbiosis and altered host-microbiota interactions. However, plasma metabolite profiles and their relationships to oral/gut microbiota in hypertension have not been evaluated in depth. Plasma, saliva, subgingival plaques, and feces were collected from 52 hypertensive participants and 24 healthy controls in a cross-sectional cohort. Untargeted metabolomic profiling of plasma was performed using high-performance liquid chromatography-mass spectrometry. Microbial profiling of oral and gut samples was determined via 16S rRNA and metagenomic sequencing. Correlations between metabolites and clinic parameters/microbiota were identified using Spearman's correlation analysis. Metabolomic evaluation showed distinct clusters of metabolites in plasma between hypertensive participants and control participants. Hypertensive participants had six significantly increased and thirty-seven significantly decreased plasma metabolites compared to controls. The plasma metabolic similarity significantly correlated with the community similarity of microbiota. Both oral and gut microbial community composition had significant correlations with metabolites such as Sphingosine 1-phosphate, a molecule involved in the regulation of blood pressure. Plasma metabolites had a larger number of significant correlations with bacterial genera than fungal genera. The shared oral/gut bacterial genera had more correlations with metabolites than unique genera but shared fungal genera and metabolites did not show clear clusters. The hypertension group had fewer correlations between plasma metabolites and bacteria/fungi than controls at species level. The integrative analysis of plasma metabolome and oral/gut microbiome identified unreported alterations of plasma metabolites in hypertension and revealed correlations between altered metabolites and oral/gut microbiota. These observations suggested metabolites and microbiota may become valuable targets for therapeutic and preventive interventions of hypertension.

Enhancer variants on chromosome 2p14 regulating SPRED2 and ACTR2 act as a signal amplifier to protect against rheumatoid arthritis

Genome-wide association studies (GWASs) have repeatedly reported multiple non-coding single-nucleotide polymorphisms (SNPs) at 2p14 associated with rheumatoid arthritis (RA), but their functional roles in the pathological mechanisms of RA remain to be explored. In this study, we integrated a series of bioinformatics and functional experiments and identified three intronic RA SNPs (rs1876518, rs268131, and rs2576923) within active enhancers that can regulate the expression of SPRED2 directly. At the same time, SPRED2 and ACTR2 influence each other as a positive feedback signal amplifier to strengthen the protective role in RA by inhibiting the migration and invasion of rheumatoid fibroblast-like synoviocytes (FLSs). In particular, the transcription factor CEBPB preferentially binds to the rs1876518-T allele to increase the expression of SPRED2 in FLSs. Our findings decipher the molecular mechanisms behind the GWAS signals at 2p14 for RA and emphasize SPRED2 as a potential candidate gene for RA, providing a potential target and direction for precise treatment of RA.

Hyptis obtusiflora C. Presl ex Benth Methanolic Extract Exhibits Anti-Inflammatory and Anti-Gastritis Activities via Suppressing AKT/NF-κB Pathway

Inflammation is an indispensable part of the human body's self-defense mechanism against external stimuli. The interactions between Toll-like receptors and microbial components trigger the innate immune system via NF-κB signaling, which regulates the overall cell signaling including inflammatory responses and immune modulations. The anti-inflammatory effects of Hyptis obtusiflora C. Presl ex Benth, which has been used as a home remedy for gastrointestinal disorders and skin disease in rural areas of Latin America, have not yet been studied. Here, we investigate the medicinal properties of Hyptis obtusiflora C. Presl ex Benth methanol extract (Ho-ME) for inflammatory response suppression. Nitric oxide secretion in RAW264.7 cells triggered by TLR2, 3, or 4 agonists was reduced by Ho-ME. Reduction of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, and interleukin (IL)-1b mRNA expression was observed. Decreased transcriptional activity in TRIF- and MyD88-overexpressing HEK293T cells was detected with a luciferase assay. Additionally, serially downregulated phosphorylation of kinase in the NF-κB pathway by Ho-ME was discovered in lipopolysaccharide-treated RAW264.7 cells. Together with the overexpression of its constructs, AKT was identified as a target protein of Ho-ME, and its binding domains were reaffirmed. Moreover, Ho-ME exerted gastroprotective effects in an acute gastritis mouse model generated by the administration of HCl and EtOH. In conclusion, Ho-ME downregulates inflammation via AKT targeting in the NF-κB pathway, and the combined results support Hyptis obtusiflora as a new candidate anti-inflammatory drug.

Non-invasive metabolic profiling of inflammation in joints and entheses by multispectral optoacoustic tomography

OBJECTIVE

To explore the metabolic characteristics of arthritis and enthesitis using multispectral opto-acoustic tomography (MSOT), a technology using near-infrared multispectral laser to stimulate tissues and detect the emitted acoustic energy, enabling non-invasive quantification of tissue components in vivo based on differential absorbance at multiple wavelengths.

METHODS

We performed a cross-sectional study in patients with RA or PsA and healthy controls (HCs). Participants underwent clinical, ultrasonographic and MSOT examination of MCP and wrist joints as well as the entheses of the common extensor tendon at the lateral humeral epicondyles and of the patellar, quadriceps and Achilles tendon. MSOT-measured haemoglobin (Hb), oxygen saturation, collagen and lipid levels were quantified and scaled mean differences between affected and unaffected joints and entheses were calculated as defined by clinical examination or ultrasonography using linear mixed effects models.

RESULTS

We obtained 1535 MSOT and 982 ultrasonography scans from 87 participants (34 PsA, 17 RA, 36 HCs). Entheseal tenderness was not associated with significant metabolic changes, whereas enthesitis-related sonographic changes were associated with increased total Hb, oxygen saturation and collagen content. In contrast, the presence of arthritis-related clinical and sonographic findings showed increased Hb levels, reduced oxygen saturation and reduced collagen content. Synovial hypertrophy was associated with increased lipid content in the joints.

CONCLUSION

MSOT allows determination of distinct metabolic differences between arthritis and enthesitis in a non-invasive setting in humans in vivo.

Synovial tissue metabolomics analysis of the therapeutic effects of stir-fried Xanthii Fructus on rheumatoid arthritis in rats

Rheumatoid arthritis (RA) is a rheumatic disease that easily causes synovial hyperplasia and joint damage. Comprehensive metabolomic profiling of synovial tissue can reveal local pathological changes during RA and identify metabolites as candidate biomarkers. Detecting metabolites in synovial tissue can more directly reflect the pathological state and disease activity associated with it. stir-fried Xanthii Fructus has demonstrated efficacy in treating RA, but its pharmacodynamic property and mechanism of action are unclear. In this study, the molecular composition of the extract of stir-fried Xanthium Fructus was determined through HPLC. The major components that exert anti-inflammatory and analgesic effects were speculated to be phenolic acids. Next, the effect of stir-fried Xanthii Fructus extracts in RA treatment was comprehensively evaluated using rat body weight, foot volume, inflammatory factors, and histopathological sections of the ankle joint as evaluation indicators. The results showed that the extract of stir-fried Xanthii Fructus could significantly reduce the inflammatory response and improve the degree of joint swelling and the imbalance between pro-inflammatory and anti-inflammatory in adjuvant arthritis rats. Finally, non-targeted metabolomics based on UPLC-Q-TOF/MS and multivariate statistical analysis were used to explore the changes of endogenous metabolites in synovium tissues and to search for potential biomarkers and related metabolic pathways in stir-fried Xanthii Fructus extract-treated AA rats. The results showed that stir-fried Xanthii Fructus mainly treated RA by regulating energy metabolism, hormone metabolism, amino acid metabolism and oxidative stress response in adjuvant arthritis rats. This study provides a theoretical basis for the mechanism of action of stir-fried Xanthii Fructus extract in treating RA.

Distinct subsets of neutrophils crosstalk with cytokines and metabolites in patients with sepsis

Sepsis is a life-threatening condition caused by a dysregulated host response to infection. Despite continued efforts to understand the pathophysiology of sepsis, no effective therapies are currently available. While singular components of the aberrant immune response have been investigated, comprehensive studies linking different data layers are lacking. Using an integrated systems immunology approach, we evaluated neutrophil phenotypes and concomitant changes in cytokines and metabolites in patients with sepsis. Our findings identify differentially expressed mature and immature neutrophil subsets in patients with sepsis. These subsets correlate with various proteins, metabolites, and lipids, including pentraxin-3, angiopoietin-2, and lysophosphatidylcholines, in patients with sepsis. These results enabled the construction of a statistical model based on weighted multi-omics linear regression analysis for sepsis biomarker identification. These findings could help inform early patient stratification and treatment options, and facilitate further mechanistic studies targeting the trifecta of surface marker expression, cytokines, and metabolites.

Long non-coding RNA MEG3 and its genetic variant rs941576 are associated with rheumatoid arthritis pathogenesis in Egyptian patients

BACKGROUND

Rheumatoid arthritis (RA) is a joint destructive disorder. This study aimed to assess lncRNA MEG3 expression and its variant rs941576 in Egyptian patients with RA.

SUBJECTS AND METHODS

100 RA patients and 100 healthy individuals were enrolled in the study. Quantitative PCR was used for expression analysis and allelic discrimination technology for genotyping.

RESULTS

LncRNA MEG3 was down-regulated in RA patients and negatively associated with RA clinical features and HIF-1α and VEGF serum levels. On the contrary, it was positively associated with BAX serum levels in RA patients. The major A allele of rs941576 variant was associated with RA patients (p = .0003). AA genotype showed a significant decrease in lncRNA MEG3 expression and BAX and increase in HIF-1α and VEGF.

CONCLUSIONS

Serum lncRNA MEG3 expression showed negative association with increased susceptibility to RA. MEG3 gene rs941576 (A/G) polymorphism was associated with increased severity of RA in the current population.

Acute and chronic inflammation alter immunometabolism in a cutaneous delayed-type hypersensitivity reaction (DTHR) mouse model

T-cell-driven immune responses are responsible for several autoimmune disorders, such as psoriasis vulgaris and rheumatoid arthritis. Identification of metabolic signatures in inflamed tissues is needed to facilitate novel and individualised therapeutic developments. Here we show the temporal metabolic dynamics of T-cell-driven inflammation characterised by nuclear magnetic resonance spectroscopy-based metabolomics, histopathology and immunohistochemistry in acute and chronic cutaneous delayed-type hypersensitivity reaction (DTHR). During acute DTHR, an increase in glutathione and glutathione disulfide is consistent with the ear swelling response and degree of neutrophilic infiltration, while taurine and ascorbate dominate the chronic phase, suggesting a switch in redox metabolism. Lowered amino acids, an increase in cell membrane repair-related metabolites and infiltration of T cells and macrophages further characterise chronic DTHR. Acute and chronic cutaneous DTHR can be distinguished by characteristic metabolic patterns associated with individual inflammatory pathways providing knowledge that will aid target discovery of specialised therapeutics.

Nuclear magnetic resonance spectroscopy-based tissue metabolomics is used to define detailed temporal signatures of acute and chronic inflammation in cutaneous delayed-type hypersensitivity reaction.

The change of plasma metabolic profile and gut microbiome dysbiosis in patients with rheumatoid arthritis

Objective

Rheumatoid arthritis (RA) is a chronic inflammatory joint disease, which is associated with progressive disability, systemic complications, and early death. But its etiology and pathogenesis are not fully understood. We aimed to investigate the alterations in plasma metabolite profiles, gut bacteria, and fungi and their role of them in the pathogenesis of RA.

Methods

Metabolomics profiling of plasma from 363 participants including RA (n = 244), systemic lupus erythematosus (SLE, n = 50), and healthy control (HC, n = 69) were performed using the ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry. The differentially expressed metabolites were selected among groups and used to explore important metabolic pathways. Gut microbial diversity analysis was performed by 16S rRNA sequencing and ITS sequencing (RA = 195, HC = 269), and the specific microbial floras were identified afterward. The diagnosis models were established based on significant differential metabolites and microbial floras, respectively.

Results

There were 63 differential metabolites discovered between RA and HC groups, mainly significantly enriched in the arginine and proline metabolism, glycine, serine, and threonine metabolism, and glycerophospholipid metabolism between RA and HC groups. The core differential metabolites included L-arginine, creatine, D-proline, ornithine, choline, betaine, L-threonine, LysoPC (18:0), phosphorylcholine, and glycerophosphocholine. The L-arginine and phosphorylcholine were increased in the RA group. The AUC of the predictive model was 0.992, based on the combination of the 10 differential metabolites. Compared with the SLE group, 23 metabolites increased and 61 metabolites decreased in the RA group. However, no significant metabolic pathways were enriched between RA and SLE groups. On the genus level, a total of 117 differential bacteria genera and 531 differential fungal genera were identified between RA and HC groups. The results indicated that three bacteria genera (Eubacterium_hallii_group, Escherichia-Shigella, Streptococcus) and two fungal genera (Candida and Debaryomyces) significantly increased in RA patients. The AUC was 0.80 based on a combination of six differential bacterial genera and the AUC was 0.812 based on a combination of seven differential fungal genera. Functional predictive analysis displayed that differential bacterial and differential fungus both were associated with KEGG pathways involving superpathway of L-serine and glycine biosynthesis I, arginine, ornithine, and proline interconversion.

Conclusion

The plasma metabolism profile and gut microbe profile changed markedly in RA. The glycine, serine, and threonine metabolism and arginine and proline metabolism played an important role in RA.

Systems biology approach delineates critical pathways associated with disease progression in rheumatoid arthritis

Rheumatoid Arthritis (RA) is a chronic systemic autoimmune disease leading to inflammation, cartilage cell death, synoviocyte proliferation, and increased and impaired differentiation of osteoclasts and osteoblasts leading to joint erosions and deformities. Transcriptomics, proteomics, and metabolomics datasets were analyzed to identify the critical pathways that drive the RA pathophysiology. Single nucleotide polymorphisms (SNPs) associated with RA were analyzed for the functional implications, clinical outcomes, and blood parameters later validated by literature. SNPs associated with RA were grouped into pathways that drive the immune response and cytokine production. Further gene set enrichment analysis (GSEA) was performed on gene expression omnibus (GEO) data sets of peripheral blood mononuclear cells (PBMCs), synovial macrophages, and synovial biopsies from RA patients showed enrichment of Th1, Th2, Th17 differentiation, viral and bacterial infections, metabolic signalling and immunological pathways with potential implications for RA. The proteomics data analysis presented pathways with genes involved in immunological signaling and metabolic pathways, including vitamin B12 and folate metabolism. Metabolomics datasets analysis showed significant pathways like amino-acyl tRNA biosynthesis, metabolism of amino acids (arginine, alanine aspartate, glutamate, glutamine, phenylalanine, and tryptophan), and nucleotide metabolism. Furthermore, our commonality analysis of multi-omics datasets identified common pathways with potential implications for joint remodeling in RA. Disease-modifying anti-rheumatic drugs (DMARDs) and biologics treatments were found to modulate many of the pathways that were deregulated in RA. Overall, our analysis identified molecular signatures associated with the observed symptoms, joint erosions, potential biomarkers, and therapeutic targets in RA. Communicated by Ramaswamy H. Sarma.

Time to Deal with Rheumatoid Cachexia: Prevalence, Diagnostic Criteria, Treatment Effects and Evidence for Management

Cachexia is an early result of rheumatoid arthritis (RA) (rheumatoid cachexia, RC), characterised mainly by involuntary loss of fat-free mass. RC is apparent in 1-67% of patients with RA, depending on the diagnostic criteria applied and the method used for the assessment of body composition. RC is associated with increased inflammation and disability, lower health perception, and greater mortality risk. These changes in body composition are driven by the inflammation process, the low levels of physical activity, the underlying testosterone deficiency and hypogonadism, and the pharmacotherapy required for RA. Chronic inflammation enhances resting energy expenditure as a response to stress, inducing an energy deficit, further propelling protein turnover. The use of corticosteroids and tumour necrosis factor α (TNF-α) inhibitors tend to increase fat accumulation, whereas other disease-modifying antirheumatic drugs (DMARDs) appear to induce increments in fat-free mass. The present review presents all information regarding the prevalence of RC, diagnostic criteria, and comorbidities, as well as the effects of pharmacotherapy and medical nutrition therapy on body composition of patients with RA.

PCBP1 is associated with rheumatoid arthritis by affecting RNA products of genes involved in immune response in Th1 cells

Rheumatoid arthritis (RA) is an autoimmune disease characterized by persistent synovitis, in which T helper 1 (Th1) can promote the development of a pro-inflammatory microenvironment. Poly(rC)-binding protein 1 (PCBP1) has been identified as a promising biomarker of RA, while its molecular mechanisms in RA development are unknown. As a canonical RNA binding protein, we propose that PCBP1 could play roles in RA by affecting both expression and alternative splicing levels in Th1 cells. Here, microarray datasets (GSE15573 and GSE23561), including 102 peripheral blood mononuclear cell samples from 39 RA patients and 63 controls, were used to evaluate the PCBP1 expression changes in RA patients. High throughput sequencing data (GSE84702) of iron driven pathogenesis in Th1 cells were downloaded and reanalyzed, including two Pcbp1 deficiency samples and two control samples in Th1 cells. In addition, CLIP-seq data of PCBP1 in Jurkat T cells was also analyzed to investigate the regulatory mechanisms of PCBP1. We found PCBP1 were down-regulated in RA specimens compared with control. The result of differentially expressed genes (DEGs) showed that Pcbp1 silencing in Th1 cells affected the expression of genes involved in immune response pathway. Alternative splicing analysis also revealed that PCBP1-regulated alternative splicing genes (RASGs) were enriched in TNF-a/NF-κB signaling pathway, T cell activation, T cell differentiation and T cell differentiation associated immune response pathways, which were highly associated with RA. DEGs and RASGs by Pcbp1 deficiency in mice were validated in PBMCs specimens of RA patients by RT-qPCR. Investigation of the CLIP-seq data revealed PCBP1 preferred to bind to 3′UTR and intron regions. PCBP1-bound genes were also significantly associated with RASGs, identifying 102 overlapped genes of these two gene sets. These genes were significantly enriched in several immune response related pathways, including myeloid cell differentiation and positive regulation of NF-κB transcription factor activity. Two RA-related genes, PML and IRAK1, were screened from the above immune related pathways. These results together support our hypothesis that PCBP1 can regulate the expression of genes involved in immune response pathway, and can bind to and regulate the alternative splicing of immune response related genes in immune T cells, and ultimately participate in the molecular mechanism of RA, providing new research ideas and directions for clinical diagnosis and treatment.

Transcriptome Reveals Granulosa Cells Coping through Redox, Inflammatory and Metabolic Mechanisms under Acute Heat Stress

Heat stress affects granulosa cells (GCs) and the ovarian follicular microenvironment, causing poor oocyte developmental competence and fertility. This study aimed to investigate the physical responses and global transcriptomic changes in bovine GCs to acute heat stress (43 °C for 2 h) in vitro. Heat-stressed GCs exhibited transient proliferation senescence and resumed proliferation at 48 h post-stress, while post-stress immediate culture-media change had a relatively positive effect on proliferation resumption. Increased accumulation of reactive oxygen species and apoptosis was observed in the heat-stress group. In spite of the upregulation of inflammatory (CYCS, TLR2, TLR4, IL6, etc.), pro-apoptotic (BAD, BAX, TNFSF9, MAP3K7, TNFRSF6B, FADD, TRADD, RIPK3, etc.) and caspase executioner genes (CASP3, CASP8, CASP9), antioxidants and anti-apoptotic genes (HMOX1, NOS2, CAT, SOD, BCL2L1, GPX4, etc.) were also upregulated in heat-stressed GCs. Progesterone and estrogen hormones, along with steroidogenic gene expression, declined significantly, in spite of the upregulation of genes involved in cholesterol synthesis. Out of 12,385 differentially expressed genes (DEGs), 330 significant DEGs (75 upregulated, 225 downregulated) were subjected to KEGG functional pathway annotation, gene ontology enrichment, STRING network analyses and manual querying of DEGs for meaningful molecular mechanisms. High inflammatory response was found to be responsible for oxidative-stress-mediated apoptosis of GCs and nodes towards the involvement of the NF-κB pathway and repression of the Nrf2 pathway. Downregulation of MDM4, TP53, PIDD1, PARP3, MAPK14 and MYC, and upregulation of STK26, STK33, TGFB2, CDKN1A and CDKN2A, at the interface of the MAPK and p53 signaling pathway, can be attributed to transient cellular senescence and apoptosis in GCs. The background working of the AMPK pathway through upregulation of AKT1, AMPK, SIRT1, PYGM, SLC2A4 and SERBP1 genes, and downregulation of PPARGCIA, IGF2, PPARA, SLC27A3, SLC16A3, TSC1/2, KCNJ2, KCNJ16, etc., evidence the repression of cellular transcriptional activity and energetic homeostasis modifications in response to heat stress. This study presents detailed responses of acute-heat-stressed GCs at physical, transcriptional and pathway levels and presents interesting insights into future studies regarding GC adaptation and their interaction with oocytes and the reproductive system at the ovarian level.

Butin Attenuates Arthritis in Complete Freund's Adjuvant-Treated Arthritic Rats: Possibly Mediated by Its Antioxidant and Anti-Inflammatory Actions

The present research work was planned to evaluate the antioxidant and anti-inflammatory actions of butin in preventing complete Freund’s adjuvant-induced arthritis in rats. Adult Wistar rats (200–240 g) were segregated equally into four groups: Group I (normal) and Group II complete Freund’s adjuvant (CFA control) were administered orally with 3 ml/kg of 0.5% SCMC (vehicle); Group III and Group IV were test groups and orally administered 25 and 50 mg/kg of butin. These oral treatments were administered for a total of 21 days. In the 21-day treatment schedule, on the first day, animals from group I (normal control) were injected a single dose of normal saline (0.1 ml) intradermally into one of the hind paws, and animals from Group II to IV were injected CFA (0.1 ml) intradermally into one of the hind paws. During the treatment schedule, the volume of the hind paw and body weight were recorded at every 7 days intervals, and animals were scored for severe arthritis on days 17, 19, and 21. On the 22nd day, samples of blood were withdrawn by puncturing the retro-orbital sinus for analysis of RBC, WBC, hemoglobin, ALT, AST, ALP, PGE2, and cytokines. After blood withdrawal, animals were euthanized; the paw was separated by cutting at the ankle joint and used for analysis of oxidative stress and antioxidant parameters, as well as for the histopathological study. Administration of butin to CFA-treated animals significantly attenuated the CFA-induced inflammatory response, oxidative stress, and reversed the histopathological alteration towards normal. According to the findings, butin has anti-inflammatory and anti-arthritic properties in rats with CFA-induced arthritis.

The effects of acupuncture and related techniques on patients with rheumatoid arthritis: A systematic review and meta-analysis

BACKGROUND

One new type of acupuncture and related techniques (ACNRT) is increasingly used by rheumatoid arthritis (RA) patients to control their disease and improve their quality of life. However, the efficacy of using ACNRT in combination with western medicine (WM) for this purpose remains unknown.

METHODS

Randomized controlled trials of ACNRT and WM treatments for RA from January 1, 2000, to January 31, 2021, were searched for in the databases PubMed, Embase, Medline, and the Cochrane Central Register of Controlled Trials, as well as in three Chinese databases: China National Knowledge Infrastructure, Wanfang Data, and Airiti Library. The primary outcomes consisted of inflammatory markers including C reactive protein (CRP), erythrocyte sedimentation rate (ESR), and rheumatoid factor. The secondary outcomes were clinical characteristics including pain visual analog scale (VAS) score, Disease Activity Score (DAS-28), swollen joints count (SJC), tender joints count (TJC), morning stiffness, and the results of a health assessment questionnaire. The three types of ACNRT used in the focal trials were acupuncture, moxibustion, and electro-acupuncture. Two qualified researchers extracted data from these trials' results and independently assessed their risk of bias. Statistical analyses were performed using Comprehensive Meta-Analysis V3 software.

RESULTS

A total of 12 RCTs with 874 patients met the inclusion criteria. As compared with the patients who received WM treatment alone, those who were given integrated ACNRT/WM treatment showed greater reductions in CRP (weighted mean difference [WMD]: -6.299; 95% CI: -9.082 to -3.517), ESR (WMD: -6.563; 95% CI: -8.604 to -4.522), VAS (WMD: -1.089; 95% CI: -1.575 to -0.602), DAS-28 (WMD: -0.633; 95% CI: -1.006 to -0.259), SJC (WMD: -1.921; 95% CI: -3.635 to -0.207), and TJC (WMD: -1.491; 95% CI: -2.941 to -0.042).

CONCLUSION

This meta-analysis of RA provides reliable evidence in favor of ACNRT plus WM. However, longer term, high-quality, repeatable, multicenter randomized controlled trials with larger sample sizes are needed.

YWHAH Genetic Variants are Associated with Increased Hypoxia Inducible Factor-1α/Vascular Endothelial Growth Factor in Egyptian Rheumatoid Arthritis Patients

The 14-3-3 Eta (14-3-3 η) biomarker platform is a relatively recent discovery with the potential to significantly address the diagnosis and prognosis of rheumatoid arthritis (RA) disease. Hypoxia-inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF) have been implicated in inflammatory mechanisms in RA. We hypothesized a molecular association of the coding YWHAH gene and its expressed protein 14-3-3 η with hypoxia and angiogenesis in RA. One hundred healthy subjects and 100 RA patients were enrolled in the study. YWHAH gene expression was determined using quantitative PCR, and its gene polymorphism rs2858750 was assessed by Taqman genotyping assay. Serum levels of 14-3-3 η, HIF-1α, and VEGF were measured using the ELISA technique, and clinical parameters were routinely examined. In RA patients, significant positive correlations were found between 14-3-3 η, HIF-1α (r = 0.84), and VEGF (r = 0.85). YWHAH gene expression was upregulated 10.8 fold (CI 95% 10.1-11.5) in RA patients and significantly correlated with all disease activity parameters, ACPA, and levels of 14-3-3 η, HIF-1α, and VEGF. RA patients showed a higher frequency of YWHAH rs2858750 A allele than healthy subjects (p = 0.02). The risk A allele carriers showed higher disease activity parameters, ACPA, YWHAH gene expression, and increased serum levels of 14-3-3 η (p < 0.001), HIF-1α (p = 0.002), and VEGF (p = 0.001) than the G allele. Serum 14-3-3 η and its rs2858750 genetic variant are associated with increased hypoxia and angiogenesis in RA and activity, and severity of the disease.

Transplantation of decellularised human amniotic membranes seeded with mesenchymal stem cell-educated macrophages into animal models

The reconstruction of chronic skin wounds remains a public health challenge in dermatology. Precisely controlling and monitoring the wound-healing process should result in enhanced outcomes for the patient. Cell-based therapies have shown great potential in medicine due to their immunomodulatory and healing properties. Herein, we produced activated macrophages by treating circulating monocytes with mesenchymal stem cell (MSC) supernatant. We also demonstrated the critical role of activated macrophages transplantation using amniotic membranes in accelerating wound healing in an animal wound model. The activated macrophages not only exhibited immunomodulatory cytokines like transforming growth factorβ (TGFβ) and interleukin 10 (and IL10) secretion but also showed attachment and proliferation ability on the amniotic membrane scaffold. Moreover, MSCs supernatant-treated cells also displayed significant ARG1, CD206, and IL 10 genes expression. Inspired by the in vitro results, we examined the in vivo therapeutic efficacy of the activated macrophage transplantation using an acellular amniotic membrane carrier in a full-thickness cutaneous wound model. The wound healing rate was significant in the group treated with macrophages generated via mesenchymal cell therapy seeded human amniotic membrane. There was less scarring in the wound sites after placing cell-scaffold constructs in the wound sites in the animal models. Overall, macrophages stimulated with mesenchymal cells' supernatant exhibited improved healing processes in incisional wounds by decreasing the inflammatory phase, increasing angiogenesis, and reducing scar tissue development.

MDMA related neuro-inflammation and adenosine receptors

3,4-methylenedioxymethamphetamine (MDMA) is a world-wide abused psychostimulant, which has the neurotoxic effects on dopaminergic and serotonergic neurons in both rodents and non-human primates. Adenosine acts as a neurotransmitter in the brain through the activation of four specific G-protein-coupled receptors and it acts as a neuromodulator of dopamine neurotransmission. Recent studies suggest that stimulation of adenosine receptors oppose many behavioral effects of methamphetamines. This review summarizes the specific cellular mechanisms involved in MDMA neuroinflammatory effects, along with the protective effects of adenosine receptors.

Microfluidic electrochemical magnetoimmunosensor for ultrasensitive detection of interleukin-6 based on hybrid of AuNPs and graphene

Cytokines are important factors in the early diagnosis of autoimmune diseases and require high sensitivity, high selectivity and quantitative detection. We proposed a miniaturized electrochemical magneto-immunosensor (EC-MIS) on portable interleukin-6 (IL-6) detection based on this requirement. Firstly, a micro-fabricated working electrode is electrochemically modified with a hybrid of reduced graphene oxide (rGO) and gold nanoparticles (AuNPs). Increased surface area and enhanced charge transfer rate improve the performance of this immunosensor on sensitivity. Secondly, magnetic beads attached with the capture antibody (cAb) are employed in sandwich immunoassay. This kind of immunoassay is immobilized on the working electrode surface by an external magnet to enrich the analyte IL-6. Thirdly, the last two features are combined and integrated on a microfluidic device in order to restrict the sample at certain areas and ease the operation of detection. With our prototypic EC-MIS operated in amperometric mode, we have achieved the detection of IL-6 with a linear range from 0.97 to 250 pg/mL and a limit of detection (LOD) of 0.42 pg/mL. Real serum samples were demonstrated and compared with benchtop equipment's results.

Evaluation of the mechanisms of sarcopenia in chronic inflammatory disease: protocol for a prospective cohort study

Background

Several chronic inflammatory diseases co-exist with and accelerate sarcopenia (reduction in muscle strength, function and mass) and negatively impact on both morbidity and mortality. There is currently limited research on the extent of sarcopenia in such conditions, how to accurately assess it and whether there are generic or disease-specific mechanisms driving sarcopenia. Therefore, this study aims to identify potential mechanisms driving sarcopenia within chronic inflammatory disease via a multi-modal approach; in an attempt to help define potential interventions for future use.

Methods

This prospective cohort study will consist of a multi-modal assessment of sarcopenia and its underlying mechanisms. Recruitment will target three chronic inflammatory diseases: chronic liver disease (CLD) (n=50), with a subset of NAFLD (n=20), inflammatory bowel disease (IBD) (n=50) and rheumatoid arthritis (RA) (n=50) both before and after therapeutic intervention. In addition, 20 age and sex matched healthy individuals will be recruited for comparison. Participants will undergo 4 assessment visits at weeks 0, 2, 12 and 24. Visits will consist of the following assessments: blood tests, anthropometrics, functional assessment, quadriceps muscle imaging, actigraphy, quality of life questionnaires, food diary collection and muscle biopsy of the vastus lateralis (at weeks 2 and 24 only). In addition, stool and urine samples will be collected for future microbiome and metabolomics analysis.

Discussion

This is the first study to use a multi-modal assessment model to phenotype sarcopenia in these chronic inflammatory diseases. We hope to identify generic as well as disease-specific mechanisms driving sarcopenia. We appreciate that these cohorts do require separate standards of care treatments which limit comparison between groups.

Ethics and dissemination

The study is approved by the Health Research Authority - West Midlands Solihull Research Ethics Service Committee Authority (REC reference: 18/WM/0167). Recruitment commenced in January 2019 and will continue until July 2021. The study was halted in March 2020 and again in January 2021 with the COVID-19 pandemic. The findings will be disseminated through peer-reviewed publications and conference presentations. All data will be stored on a secure server.

Trial registration

ClinicalTrials.gov Identifier: NCT04734496

Serum metabolomic and lipidomic profiling identifies diagnostic biomarkers for seropositive and seronegative rheumatoid arthritis patients

BACKGROUND

Diagnosing seronegative rheumatoid arthritis (RA) can be challenging due to complex diagnostic criteria. We sought to discover diagnostic biomarkers for seronegative RA cases by studying metabolomic and lipidomic changes in RA patient serum.

METHODS

We performed comprehensive metabolomic and lipidomic profiling in serum of 225 RA patients and 100 normal controls. These samples were divided into a discovery set (n = 243) and a validation set (n = 82). A machine-learning-based multivariate classification model was constructed using distinctive metabolites and lipids signals.

RESULTS

Twenty-six metabolites and lipids were identified from the discovery cohort to construct a RA diagnosis model. The model was subsequently tested on a validation set and achieved accuracy of 90.2%, with sensitivity of 89.7% and specificity of 90.6%. Both seropositive and seronegative patients were identified using this model. A co-occurrence network using serum omics profiles was built and parsed into six modules, showing significant association between the inflammation and immune activity markers and aberrant metabolism of energy metabolism, lipids metabolism and amino acid metabolism. Acyl carnitines (20:3), aspartyl-phenylalanine, pipecolic acid, phosphatidylethanolamine PE (18:1) and lysophosphatidylethanolamine LPE (20:3) were positively correlated with the RA disease activity, while histidine and phosphatidic acid PA (28:0) were negatively correlated with the RA disease activity.

CONCLUSIONS

A panel of 26 serum markers were selected from omics profiles to build a machine-learning-based prediction model that could aid in diagnosing seronegative RA patients. Potential markers were also identified in stratifying RA cases based on disease activity.

NMR-based untargeted metabolomics approach to investigate the systemic lipid metabolism regulation of norisoboldine in collagen-induced arthritis rats

Norisoboldine (NOR), an isoquinoline alkaloid, has previously been shown to ameliorate collagen-induced arthritis (CIA) by modulating the function of multiple cells such as T lymphocytes and fibroblast-like synoviocytes. To further study its anti-arthritis mechanism, the effect of NOR on the systemic metabolism regulation was investigated using an NMR-based untargeted metabolomics approach. CIA model rats were orally administered with NOR (30 mg/kg) for 14 consecutive days. The alterations of endogenous metabolites in the urine samples were quantified by 1H NMR. While NOR significantly mitigated CIA in rats as evidenced by the reduced clinical scores and histopathological changes, the results indicated that the treatment restored the levels of 22 metabolites that were significantly changed by arthritis, and most of which were related to lipid metabolism. Further studies demonstrated that NOR up-regulated the expression of carnitine palmitoyltransferase 1 (CPT-1) and down-regulated the expression of fatty acid synthase (FASN) in the spleens and the synovial tissues of CIA rats. Together these results revealed a strong association between RA and the system in metabolic disorders. The differential metabolites and their related pathways may also serve as novel therapeutic targets for RA.

AGE/Non-AGE Glycation: An Important Event in Rheumatoid Arthritis Pathophysiology

Rheumatoid arthritis (RA) is a chronic inflammatory, autoimmune disease that gradually affects the synovial membrane and joints. Many intrinsic and/or extrinsic factors are crucial in making RA pathology challenging throughout the disease. Substantial enzymatic or non-enzymatic modification of proteins driving inflammation has gained a lot of interest in recent years. Endogenously modified glycated protein influences disease development linked with AGEs/non-AGEs and is reported as a disease marker. In this review, we summarized current knowledge of the differential abundance of glycated proteins by compiling and analyzing a variety of AGE and non-AGE ligands that bind with RAGE to activate multi-faceted inflammatory and oxidative stress pathways that are pathobiologically associated with RA-fibroblast-like synoviocytes (RA-FLS). It is critical to comprehend the connection between oxidative stress and inflammation generation, mediated by glycated protein, which may bind to the receptor RAGE, activate downstream pathways, and impart immunogenicity in RA. It is worth noting that AGEs and non-AGEs ligands play a variety of functions, and their functionality is likely to be more reliant on pathogenic states and severity that may serve as biomarkers for RA. Screening and monitoring of these differentially glycated proteins, as well as their stability in circulation, in combination with established pre-clinical characteristics, may aid or predict the onset of RA.

Vitamin Status as Predictors in Rheumatoid Arthritis

Musculoskeletal disorders are the leading cause of long term disability in EU with a significant impact on health care system and with increased social and economic costs. Despite of recent advances in Rheumatoid arthritis (RA) research field, here is still lacking of specific biomarkers that can be used in order to distinguish between different RA patterns and the clinical criteria are still the main tool used only for classification of diseases. Our hypothesis is that the vitamin deficiency associated with chronic inflammation can lead to a mild increase in Hcy level in blood that can act as predictor of increased risk of complication in RA patients. The aim of our study was to identify a correlation between level of Hcy in peripheral blood samples collected from RA patients and to establish if the Hcy level can be validate as potential predictive biomarker in RA patients treated with different DMARDs. Our findings suggest that Hcy level in plasma and CRP are independent predictors of chronic inflammatory status and are useful biomarkers in order to estimate the risk of complication in RA patients. To our knowledge to date, studies before had a controversial findings regarding the efficiency of folate and B12 vitamins supplements on decreasing the cardiovascular events risk. We showed that the folic acid and B12 supplements are important.

Metabolic syndrome and its effect on the outcomes of rheumatoid arthritis in a multi-ethnic cohort in Singapore

INTRODUCTION

Over-expression of common inflammatory mediators in the metabolic syndrome (MetS) and in rheumatoid arthritis (RA) may lead to mutually adverse outcomes.

AIM

We investigate the prevalence of MetS in a multi-ethnic population of RA patients and its effect on clinical and patient-reported outcomes.

METHOD

Six hundred sixty RA (561 women) patients from a public-sector specialist clinic in a hospital in Singapore were assessed for MetS according to the 2009 Joint Consensus (JC) and the 2004 National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) definitions. Univariable and multivariable regression modelling were used to investigate the associations between patients' demographics with MetS and MetS with RA outcomes.

RESULTS

The prevalence of MetS in our RA cohort was 49.4% and 44.9% according to the JC and NCEP ATP III definitions, respectively. The diagnosis of MetS was largely due to hypertriglyceridemia, hypertension, and obesity. MetS was associated with older age (OR 1.06 [95% CI 1.04-1.08]), Malay ethnicity (OR 1.78 [95% CI 1.02-3.09]), or Indian ethnicity (OR 3.07 [95% CI 1.68-5.59]). No significant associations between MetS and RA outcomes were observed. RA patients with MetS are more likely to suffer from stroke and ischemic heart disease.

CONCLUSION

The prevalence of MetS in RA patients in Singapore was almost double that in the general population. MetS does not adversely affect RA outcomes but raises the risks of stroke and heart disease. RA patients, especially those older and of Indian and Malay ethnicities, should be routinely screened for MetS. Any MetS-defining condition should be actively controlled. Key Points • Approximately half of the RA sample from the Singapore RA population can be diagnosed with MetS. • Older patients, and patients of Malay and Indian ethnicities have higher odds of MetS. • MetS does not adversely affect RA outcomes but raises the risks of stroke and heart disease.

Targeting immunometabolism by active ingredients derived from traditional Chinese medicines for treatment of rheumatoid arthritis

Rheumatoid arthritis (RA), the most common inflammatory arthropathy word wild, is a systemic autoimmune disease that mainly affects the synovium of joints with a high disability rate. Metabolic mis-regulation has emerged as a fundamental pathogenesis of RA linked to immune cell dysfunction, while targeting immunometabolism provides a new and effective approach to regulate the immune responses and thus alleviate the symptom of RA. Recently, natural active compounds from traditional Chinese medicines (TCMs) have potential therapeutic effects on RA and regulating immunometabolism. In this review, in addition to updating the connection between cellular metabolism and cell function in immune cells of RA, we summarized that the anti-inflammatory mechanisms of the potential natural compounds from TCM by targeting metabolic reprogramming of immune cells, and discusses them as a rich resource for providing the new potential paradigm for the treatment of RA.

Association of the Adipokines Chemerin, Apelin, Vaspin and Omentin and Their Functional Genetic Variants with Rheumatoid Arthritis

Adipokines were shown to exert crucial roles in rheumatic diseases. This study aimed to assess the role of chemerin, apelin, vaspin, and omentin adipokines and their genetic variants rs17173608, rs2235306, rs2236242, and rs2274907, respectively, in rheumatoid arthritis (RA) pathogenesis in Egyptian patients. A total of 150 RA patients and 150 healthy individuals were recruited. Blood samples were collected and used for genotyping. Serum was separated and used for expression analysis by quantitative PCR, and various biochemical markers determination by ELISA. Serum protein levels of chemerin and vaspin, as well as their gene expression levels were higher, while those of apelin and omentin were lower in RA patients and were associated with most of RA clinical and laboratory characteristics. G allele of chemerin rs17173608, T allele of vaspin rs2236242, and T allele of omentin rs2274907 were more frequent in RA patients. Serum levels and gene expression levels of chemerin in GG genotype carriers and vaspin in TT genotype group were significantly higher, while those of omentin in TT genotype carriers were significantly lower than RA patients with other genotypes. There was no association between apelin rs2235306 and RA. Chemerin rs17173608, vaspin rs2236242, and omentin rs2274907 polymorphisms were associated with increased susceptibility to RA.

Inhibition of glycolysis in the presence of antigen generates suppressive antigen-specific responses and restrains rheumatoid arthritis in mice

Dendritic cells (DCs) rely on glycolysis for their energy needs to induce pro-inflammatory antigen-specific immune responses. Therefore, inhibiting DC glycolysis, while presenting the self-antigen, may prevent pro-inflammatory antigen-specific immune responses. Previously we demonstrated that microparticles with alpha-ketoglutarate (aKG) in the polymer backbone (paKG MPs) were able to generate anti-inflammatory DCs by sustained delivery of the aKG metabolite, and by modulating energy metabolism of DCs. Herein, we demonstrate that paKG MPs-based delivery of a glycolytic inhibitor, PFK15, using paKG MPs induces anti-inflammatory DCs (CD86^LoMHCII⁺) by down-regulating glycolysis, CD86, tnf and IL-6 genes, while upregulating oxidative phosphorylation (OXPHOS) and mitochondrial genes. Furthermore, paKG MPs delivering PFK15 and a self-antigen, collagen type II (bc2), in vivo, in a collagen-induced autoimmune arthritis (CIA) mouse model, normalized paw inflammation and arthritis score, by generating antigen-specific immune responses. Specifically, these formulations were able to reduce activation of DCs in draining lymph nodes and impressively generated proliferating bc2-specific anti-inflammatory regulatory T cells in joint-associated popliteal lymph nodes. These data strongly suggest that sustained glycolytic inhibition of DCs in the presence of an antigen can induce antigen-specific immunosuppressive responses, therefore, generating a technology that can be applicable for treating autoimmune diseases.

α-Mangostin Alleviated Inflammation in Rats With Adjuvant-Induced Arthritis by Disrupting Adipocytes-Mediated Metabolism-Immune Feedback

A previously identified anti-rheumatic compound α-mangostin (MAN) possesses notable metabolism regulatory properties. In this study, we investigated the immune implication of MAN-altered fat metabolism on adjuvant-induced arthritis (AIA) in rats. Seven days after AIA induction, the rats received oral treatment of MAN at 50 mg/kg/day for 30 days. Metabolic indicators and basic clinical parameters were evaluated using samples collected on day 20 and 38 since immunization. Expression of nicotinamide phosphoribosyltransferase (NAMPT), sirtuin 1 (SIRT1), peroxisome proliferator activated receptor gamma (PPAR-γ), stearoyl-coa desaturase 1 (SCD-1), toll like receptor 4 (TLR4), prostaglandin-endoperoxide synthase 2 (COX-2), (p)-JNK, (p)-p65 and IL-1β were investigated by either RT-qPCR or immunobloting methods. In in vitro experiments, we treated (pre)-adipocytes with monocytes/macrophages and MAN, and investigated the changes of macrophages brought by pre-adipocytes co-culture. Generally, MAN restored the impaired fat anabolism in AIA rats, indicated by increased fat reservoir, leptin and adiponectin secretion, and PPAR-γ and SCD-1 expression. Meanwhile, it decreased circulating IL-1β and IL-6 levels, restored serological lipid profile changes, and relieved oxidative stresses, demonstrating potent therapeutic effects on AIA. AIA rats-derived monocytes inhibited mRNA PPAR-γ and SCD-1 expression in pre-adipocytes. Contrarily, MAN facilitated adipocyte differentiation in vitro, and increased free fatty acids production. It also significantly increased PPAR-γ and SCD-1 expression, which can be abrogated by PPAR-γ inhibitor T0070907. Similarly, lipopolysaccharide-primed macrophages inhibited PPAR-γ expression in the co-cultured pre-adipocytes, which was reversed by MAN. In the same co-culture system, lipopolysaccharide-induced inflammation was amplified by the co-existence of pre-adipocytes. More secretion of IL-1β and IL-6 and higher levels expression of COX-2, p-JNK, p-p65 and TLR4 were observed in lipopolysaccharide-treated macrophages when co-cultured by pre-adipocytes. The intensified inflammatory situation was eased by MAN. The treatment with pre-adipocytes culture medium achieved similar effects. Medium from lipopolysaccharide-treated adipocytes promoted IL-1β, IL-6 and MCP-1 production in separately cultured macrophages, and COX-2, p-JNK, p-p65 and TLR4 expression were increased at the meantime. MAN treatment on pre-adipocytes impaired these changes. It suggests that fat anabolism in AIA rats was deficient due to increased energy expenditure caused by inflammatory conditions. MAN restored fat metabolism homeostasis by up-regulating PPAR-γ, and reshaped secretion profile of adipocytes.

Celastrol inhibits rheumatoid arthritis through the ROS-NF-κB-NLRP3 inflammasome axis

Emerging evidence indicates that NOD-like receptor protein 3 (NLRP3) inflammasome-induced inflammation plays a critical role in the pathogenesis of rheumatoid arthritis (RA). Celastrol (Cel) is a quinone-methylated triterpenoid extracted from Tripterygium wilfordii that is used to treat RA. However, researchers have not determined whether Cel exerts anti-RA effects by regulating the activation of the NLRP3 inflammasome. In the present study, complete Freund's adjuvant (CFA)- induced rats and human mononuclear macrophages (THP-1 cells) were used to explore the anti-RA effects of Cel and its underlying mechanism. Joint swelling, the arthritis index score, inflammatory cell infiltration, and synovial hyperplasia in CFA-induced rats were correspondingly reduced after Cel treatment. The secretion of interleukin (IL)-1β and IL-18 in the serum of CFA-induced rats and supernatants of THP-1 cells exposed to Cel was significantly decreased. These inhibitory effects occurred because Cel blocked the nuclear factor-kappa B (NF-κB) signaling pathway and inhibited the activation of the NLRP3 inflammasome. Furthermore, Cel inhibited reactive oxygen species (ROS) production induced by lipopolysaccharide (LPS) and adenosine triphosphate (ATP). We speculated that Cel relieves RA symptoms and inhibits inflammation by inhibiting the ROS-NF-κB-NLRP3 axis.