Iguratimod inhibits protein citrullination and inflammation by downregulating NBCe2 in patients with rheumatoid arthritis.

BACKGROUND: Bicarbonate has recently been identified as a crucial factor affecting peptidylarginine deiminase (PAD) activity; however, the mechanism underlying its role in rheumatoid arthritis (RA) remains unclear. Iguratimod (IGU), a small-molecule disease-modifying anti-rheumatic drug, requires further investigation. This study aimed to explore the mechanism by which bicarbonate affects citrullination and inflammation in RA and identify new targets for IGU. METHODS: We enrolled 20 patients with RA in the study. Sodium bicarbonate cotransporter 2 (NBCe2) was detected in the peripheral blood neutrophils and peripheral blood mononuclear cells (PBMCs) of these patients. The effects of varying concentrations of IGU, methotrexate (MTX), dexamethasone (DXM), and S0859 (an NBCe2 inhibitor) on NBCe2, PAD2, PAD4, and citrullinated histone H3 (cit-H3) levels in, migration ability of, and cytokine production from neutrophils and PBMCs were examined. RESULTS: Our findings showed that in patients with RA, citrullinated protein production by peripheral blood neutrophils instead of PBMCs, which showed higher NBCe2 expression levels, increased with an increase in the bicarbonate concentration. In addition, tumor necrosis factor-alpha (TNF-α) promoted NBCe2 expression in neutrophils from patients with RA. Furthermore, we revealed that the inhibitory effects of IGU on neutrophil NBCe2 and cit-H3 levels, degrees of inhibition of neutrophil and PBMC migration, and suppression of interleukin 6, TNF-α, and metalloproteinase-9 secretion from neutrophil-like differentiated HL-60 cells did not substantially differ from those of MTX, DXM, and S0859 at specific doses. CONCLUSIONS: Bicarbonate promotes protein citrullination and inflammation in RA via NBCe2, and IGU can downregulate NBCe2.

Telitacicept in patients with active systemic lupus erythematosus: results of a phase 2b, randomised, double-blind, placebo-controlled trial.

OBJECTIVES: This phase 2b, randomised, double-blind, placebo-controlled trial evaluated the efficacy and safety of telitacicept, a novel fusion protein that neutralises signals of B lymphocyte stimulator and a proliferation-inducing ligand, in active systemic lupus erythematosus (SLE). METHODS: Adult patients with active SLE (n=249) were recruited from 29 hospitals in China and randomised 1:1:1:1 to receive subcutaneous telitacicept at 80 mg (n=62), 160 mg (n=63), 240 mg (n=62) or placebo (n=62) once weekly in addition to standard therapy. The primary endpoint was the proportion of patients achieving an SLE Responder Index 4 (SRI-4) response at week 48. Missing data were imputed using the last observation carried forward method. RESULTS: At week 48, the proportion of patients achieving an SRI-4 response was 75.8% in the 240 mg telitacicept group, 68.3% in the 160 mg group, 71.0% in the 80 mg group and 33.9% in the placebo group (all p<0.001). Significant treatment responses were observed in secondary endpoints, including a ≥4-point reduction on the Systemic Lupus Erythematosus Disease Activity Index, a lack of Physician's Global Assessment score worsening and a glucocorticoid dose reduction in the 240 mg group. Telitacicept was well tolerated, and the incidence of adverse events and serious adverse events was similar between the telitacicept and placebo groups. CONCLUSIONS: This phase 2b clinical trial met the primary endpoint. All telitacicept groups showed a significantly higher proportion of patients achieving an SRI-4 response than the placebo group at week 48, and all doses were well tolerated. These results support further investigations of telitacicept in clinical trials involving more diverse populations and larger sample sizes. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT02885610).

The transient receptor potential channels in rheumatoid arthritis: Need to pay more attention.

Rheumatoid arthritis (RA) is characterized by the augment of vascular permeability, increased inflammatory cells infiltration, dysregulated immune cells activation, pannus formation and unbearable pain hyperalgesia. Ca2+ affect almost every aspect of cellular functions, involving cell migration, signal transduction, proliferation, and apoptosis. Transient receptor potential channels (TRPs) as a type of non-selective permeable cation channels, can regulate Ca2+ entry and intracellular Ca2+ signal in cells including immune cells and neurons. Researches have demonstrated that TRPs in the mechanisms of inflammatory diseases have achieved rapid progress, while the roles of TRPs in RA pathogenesis and pain hyperalgesia are still not well understood. To solve this problem, this review presents the evidence of TRPs on vascular endothelial cells in joint swelling, neutrophils activation and their trans-endothelial migration, as well as their bridging role in the reactive oxygen species/TRPs/Ca2+/peptidyl arginine deiminases networks in accelerating citrullinated proteins formation. It also points out the distinct functions of TRPs subfamilies expressed in the nervous systems of joints in cold hyperalgesia and neuro-inflammation mutually influenced inflammatory pain in RA. Thus, more attention could be paid on the impact of TRPs in RA and TRPs are useful in researches on the molecular mechanisms of anti-inflammation and analgesic therapeutic strategies.

Efficacy and Safety of CMAB008 Compared with Innovator Infliximab in Patients with Moderate-to-Severe Rheumatoid Arthritis Receiving Concomitant Methotrexate: A Randomized, Double-blind, Multi-center, Phase III Non-inferiority Study.

OBJECTIVES: The aim of this work is to verify the non-inferior efficacy and safety of CMAB008 compared with innovator infliximab in rheumatoid arthritis patients combined with methotrexate. METHODS: We conducted a randomized, double-blinded, parallel, positive control design, multicenter study, with a stable dose of methotrexate. Patients were enrolled randomly with a ratio of 1:1 to receive intravenously CMAB008 3 mg/kg or innovator infliximab 3 mg/kg at weeks 0, 2, 6, 14, 22 and 30. The primary efficacy endpoint was American College of Rheumatology 20% improvement criteria (ACR20) response rate at week 30. The non-inferiority was established if the lower limit of the one-sided 97.5% confidence interval (CI) for the difference was more than - 15% and the equivalence was established if the two-sided 95% CI was within ± 15% in an exploratory equivalence analysis. The secondary endpoints included other efficacy assessment parameters, as well as immunogenicity, safety, and pharmacokinetics. RESULTS: In the full analysis population (FAS), 110 (57.6%) of 191 patients in the CMAB008 group and 120 (62.2%) of 193 patients in the innovator infliximab group reached the primary outcome of ACR20 at week 30. The differences of the rates were - 4.6% and the lower limit of one-sided 97.5% confidence interval was - 14.29%, not less than the lower limit of the non-inferiority margin (- 15%); so CMAB008 was non-inferior to innovator infliximab. Further, CMAB008 was equivalent to innovator infliximab both in FAS (difference - 4.6%, 95% CI - 14.29% to 5.12%) and PPS (difference - 3.3%, 95% CI - 13.18% to 6.62%). The efficacy, safety, immunogenicity, and pharmacokinetics are highly similar between CMAB008 and innovator infliximab. CONCLUSIONS: Non-inferior efficacy of CMAB008 to innovator infliximab is illustrated with similar early and lasting therapeutic effects, and the equivalence is further demonstrated. CMAB008 is well tolerated and has semblable safety compared with the innovator infliximab. TRIAL REGISTRATION NUMBER: NCT03478111.

New insights into MAIT cells in autoimmune diseases.

Mucosal-associated invariant T (MAIT) cells are resident T cells that express semi-invariant TCR chains and are restricted by monomorphic major histocompatibility complex (MHC) class I-related molecules (MR1). MAIT cells can be activated by microbial-specific metabolites (MR1-dependent mode) or cytokines (MR1-independent mode). Activated MAIT cells produce chemokines, cytotoxic molecules (granzyme B and perforin), and proinflammatory cytokines (IFN-γ, TNF-α, and IL-17), to clear pathogens and target infected cells involved in the pro-inflammatory, migratory, and cytolytic properties of MAIT cells. MAIT cells produce pro-inflammatory cytokines in the target organs of autoimmune diseases and contribute to the development and progression of autoimmune diseases. This article reviews the biological characteristics, activation mechanism, dynamic migration, and dual functions of MAIT cells, and focuses on the mechanism and potential application of MAIT cells in the early diagnosis, disease activity monitoring, and therapeutic targets of autoimmune diseases, to lay a foundation for future research.

Comparison of the efficacy and safety of the adalimumab biosimilar TQ-Z2301 and adalimumab for the treatment of Chinese patients with active ankylosing spondylitis: a multi-center, randomized, double-blind, phase III clinical trial.

OBJECTIVE: To assess the clinical equivalence of TQ-Z2301, a biosimilar of adalimumab, to the reference adalimumab in the treatment of Chinese patients with active ankylosing spondylitis. METHODS: This multicenter, randomized, double-blind, positive-controlled phase III clinical trial was conducted in 19 centers across China. Chinese adults with active ankylosing spondylitis despite being treated with non-steroidal anti-inflammatory drugs for ≥ 4 weeks were randomized in a 1:1 ratio to subcutaneously receive 40 mg of TQ-Z2301 or adalimumab every other week for 24 weeks. The primary endpoint was the percentage of patients who achieved at least 20% improvement according to the Assessment of Spondyloarthritis International Society criteria (ASAS20) at week 24. The equivalence was established if the 90% CI for RR of ASAS20 between two groups at week 24 fell within (0.80, 1.25). Secondary endpoints included efficacy measures of disease activity, spinal mobility, physical function and quality of life, immunogenicity, and pharmacokinetic parameters. Safety analysis was done for all patients who received at least one study drug. RESULTS: A total of 380 patients were enrolled in the study between September 2018 and October 2019, including 188 in the TQ-Z2301 group and 192 in the adalimumab group. In the full analysis population, the ASAS20 response rate at week 24 was 86.70% in the TQ-Z2301 group, and 80.73% in the adalimumab group, the RR of ASAS20 for TQ-Z2301 versus adalimumab was 1.074, 90% CI (0.997, 1.157), fell within the predefined equivalence boundary (0.80, 1.25). Except for the SF-36 at week 12, there was no statistical difference between the two groups for all the secondary endpoints (P>0.05). The incidence of adverse events group was 82.45% in the TQ-Z2301, and 83.85% in the adalimumab group, the safety profile of the two groups was similar. The profiles of immunogenicity and pharmacokinetics were also similar between the two groups. CONCLUSION: TQ-Z2301 is equivalent to adalimumab for the treatment of Chinese patients with active ankylosing spondylitis. The safety, immunogenicity, and pharmacokinetic characteristics of both drugs are similar. TRIAL REGISTRATION: The study (CTR20181863) was registered in the Chinese Clinical Trial Registry on 19 October 2018. Key Points • TQ-Z2301 showed the equivalence of efficacy compared with the reference adalimumab for the treatment of Chinese patients with active ankylosing spondylitis. • The safety, immunogenicity, and pharmacokinetics profiles of TQZ-2301 were similar to those of the reference adalimumab.

Efficacy and safety of a selective URAT1 inhibitor SHR4640 in Chinese subjects with hyperuricaemia: a randomized controlled phase II study.

OBJECTIVE: To evaluate the efficacy and safety of SHR4640, a highly selective urate transporter 1 inhibitor, in Chinese subjects with hyperuricaemia. METHODS: This was a randomized double-blind dose-ranging phase II study. Subjects whose serum uric acid (sUA) levels were ≥480 µmol/l with gout, ≥480 µmol/l without gout but with comorbidities, or ≥540 µmol/l were enrolled. Subjects were randomly assigned (1:1:1:1:1) to receive once daily 2.5 mg, 5 mg, 10 mg of SHR4640, 50 mg of benzbromarone or placebo, respectively. The primary end point was the proportion of subjects who achieved target sUA level of ≤360 µmol/l at week 5. RESULTS: 99.5% of subjects (n = 197) were male and 95.9% of subjects had gout history. The proportions of subjects who achieved target sUA at week 5 were 32.5%, 72.5% and 61.5% in the 5 mg, 10 mg SHR4640 and benzbromarone groups, respectively, significantly higher than the placebo group (0%; P < 0.05 for 5 mg and 10 mg SHR4640 group). The sUA was reduced by 32.7%, 46.8% and 41.8% at week 5 with 5 mg, 10 mg SHR4640 and benzbromarone, respectively, vs placebo (5.9%; P < 0.001 for each comparison). The incidences of gout flares requiring intervention were similar among all groups. Occurrences of treatment-emergent adverse events (TEAEs) were comparable across all groups, and serious TEAEs were not reported. CONCLUSIONS: The present study indicated a superior sUA-lowering effect and well tolerated safety profile after 5-week treatment with once-daily 5 mg/10 mg of SHR4640 as compared with placebo in Chinese subjects with hyperuricaemia. TRIAL REGISTRATION: ClinicalTrials.gov number, NCT03185793.

Safety and Efficacy of Prefilled Liquid Etanercept-Biosimilar Yisaipu for Active Ankylosing Spondylitis: A Multi-Center Phase III Trial.

INTRODUCTION: The aim of this work is to examine the efficacy and safety of prefilled liquid etanercept-biosimilar Yisaipu versus lyophilized Yisaipu in active ankylosing spondylitis (AS) patients. METHODS: This double-blind, phase III trial with non-inferiority design randomized adult patients with active AS in a 3:1:1 ratio to receive twice-weekly 25-mg prefilled liquid Yisaipu for a total of 48 injections (group I, n = 330), once-weekly 50-mg prefilled liquid Yisaipu for 24 injections (group II, n = 110), or twice-weekly 25-mg lyophilized Yisaipu for 48 injections (group III, n = 110). Both physicians and patients who received 25-mg twice-weekly lyophilized or liquid Yisaipu were blinded to treatment assignment while patients who received 50-mg once-weekly liquid Yisaipu received treatment in an open-label design. In addition, 90 patients in the PK/PD study were randomized in a 1:1:1 ratio to each group. The primary outcome was the proportion of patients who achieved ASAS20 at week 24. RESULTS: A total of 640 subjects were enrolled. The proportion of patients who attained ASAS20 at week 24 was 85.56% in group I, 85.71% in group II, and 83.45% in group III (group I vs. III, P = 0.545; group II vs. III, P = 0.605). The difference between group I and III was 2.10% (95% CI - 5.06%, 9.27%) and 2.26% (95% CI - 6.21%, 10.73%) between group II and III, meeting the non-inferiority threshold (Δ = - 15%) (P < 0.001). Except for a statistical difference between group I (75.83%) and group III at week 8 (64.75%, P = 0.011), there was no statistical difference in the ASAS20 attainment rate among the three groups at other time points. The incidence of serious adverse events was comparable among the three groups (group I, 2.50%, II, 2.86% and III, 1.43%; P > 0.05). No deaths were reported. CONCLUSIONS: Once-weekly 50-mg or twice-weekly 25-mg prefilled liquid Yisaipu is safe and non-inferior to twice-weekly 25-mg lyophilized Yisaipu. TRIAL REGISTRATION: CTR20130124 and NCT04345458.

Long-term Outcomes of Patients with Systemic Lupus Erythematosus: A Multicenter Cohort Study from CSTAR Registry.

Objective: To study the long-term outcomes, in the context of both mortality and organ damage in patients with systemic lupus erythematosus (SLE) in the Chinese SLE Treatment and Research group (CSTAR) registry cohort. Methods: Patients were enrolled from April 2009 to February 2010 and they were followed up. The demographic data, clinical manifestations, labs test results and imaging examinations, disease activity (SLEDAI-2K), damage scores (SLLIC/Damage Index [SDI]), and medications were collected. Data were censored at either the last clinic visit or telephonic interview. Survival rate was analyzed by Kaplan-Meier (KM) method. COX proportional hazard model was adopted to perform the analysis of predicting factors for mortality and organ damage. Logistic regression analysis was employed to discuss the relationship among mortality, organ damage, and flare. Results: A total of 2104 patients were recruited at baseline and 1494 patients were followed up. The cumulative 1-year, 3-year, and 5-year survival rates were 98.3%, 96.9%, and 95.7%, respectively. Seventy-eight patients died during follow-up, and the main causes of death were infection (34.6%), active disease (26.9%), cardiovascular and cerebrovascular events (5.13%), and malignancy (5.13%). At entry, 247 patients presented with irreversible organ damage and it increased to 398 patients at the endpoint. The major accumulated organ damages were kidney (25.9%), musculoskeletal disease (20.2%), neuropsychiatric disease (12.2%), and pulmonary damage (10.9%). Cox regression analysis further showed that male, late disease onset, delayed diagnosis (diagnosis from disease onset >1 year), baseline organ damage, and specific organ involvements predicted for higher mortality. In addition, early disease onset was a protecting factor for organ damage, and anti-SSA was an independent predicting factor for new organ damage. Logistic regression analysis showed that flare predicted for more organ damage. Conclusion: The 5-year survival rate of Chinese SLE patients has improved and is comparable to Caucasians SLE patients. Disease flare impact on prognosis is the increasing risk of damage development. Early diagnosis, prevention for flare and damage to maintain remission, may improve outcome.

Role of the NLRP3 inflammasome in autoimmune diseases.

NOD-like receptor family pyrin domain containing 3 (NLRP3) is an intracellular receptor that senses foreign pathogens and endogenous danger signals. It assembles with apoptosis-associated speck-like protein containing a CARD (ASC) and caspase-1 to form a multimeric protein called the NLRP3 inflammasome. Among its various functions, the NLRP3 inflammasome can induce the release of the pro-inflammatory cytokines interleukin (IL)-1ß and IL-18 while also promoting gasdermin D (GSDMD)-mediated pyroptosis. Previous studies have established a vital role for the NLRP3 inflammasome in innate and adaptive immune system as well as its contribution to several autoimmune diseases including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), Sjögren's syndrome (SS), systemic sclerosis (SSc), and ankylosing spondylitis (AS). In this review, we briefly introduce the biological features of the NLRP3 inflammasome and present the mechanisms underlying its activation and regulation. We also summarize recent studies that have reported on the roles of NLRP3 inflammasome in the immune system and several autoimmune diseases, with a focus on therapeutic and clinical applications.

Comparative efficacy of treatments for patients with knee osteoarthritis: a network meta-analysis.

BACKGROUND: Knee osteoarthritis is a common cause of musculoskeletal pain and a leading cause of disability and healthcare economic burden. The optimum treatment for knee osteoarthritis is still inconclusive. A network meta-analysis is required to assess the efficacy and safety of treatments and provide more scientific medical evidence. METHODS: Relevant studies were searched through PubMed, Embase, and Cochrane Library electronic databases from the inception to October 2018. Continuous outcomes such as pain, stiffness, physical function and total scores were expressed as the mean differences with 95% credible interval. Surface under the cumulative ranking curve illustrated the rank probability of each therapy under different outcomes. RESULTS: Nineteen studies were included in this study, with a total of 2395 patients. For knee pain, platelet-rich plasma (0.691) was ranked at the first place, followed by hyaluronic acid combined with platelet-rich plasma (0.670) and hyaluronic acid (0.402). In terms of stiffness, hyaluronic acid combined with platelet-rich plasma (0.743) enjoyed the highest value, platelet-rich plasma (0.603) was the next and hyaluronic acid (0.386) was the third. As for physical function, the rank was hyaluronic acid combined with platelet-rich plasma (0.772), platelet-rich plasma (0.608) and hyaluronic acid (0.343). For total scores, the order given by surface under the cumulative ranking was hyaluronic acid combined with platelet-rich plasma (0.765), platelet-rich plasma (0.624) and hyaluronic acid (0.37). CONCLUSIONS: Hyaluronic acid combined with platelet-rich plasma showed the best efficacy in improving stiffness, physical function, and total scores, while platelet-rich plasma appeared the best in terms of pain reduction.

Inhibiting role of long non-coding RNA LINC01197 in inflammation in rheumatoid arthritis through the microRNA-150/THBS2 axis.

PURPOSE: Rheumatoid arthritis (RA) is a commonly diagnosed systemic autoimmune disease. Aberrant expression of long non-coding RNAs (lncRNAs) is closely linked to the development of RA. This study was conducted to explore the functions of the lncRNA LINC01197 in RA progression. METHODS: Differentially expressed lncRNAs/microRNAs/mRNAs in patients with RA were analyzed using RNA microarrays. A mouse model with RA was established and RA-fibroblast-like synoviocytes (RA-FLS) were acquired for in vitro experiments. The function of LINC01197 in inflammation and RA progression in mice and its role in the viability of RA-FLS were determined by experiments involving its overexpression or suppression. The sub-cellular localization of LINC01197 was determined and the downstream molecules involved in LINC01197-mediated events were identified. RESULTS: LINC01197 was poorly expressed in the synovial tissues in the RA model mice. Overexpression of LINC01197 reduced RA severity in mice and inhibited proliferation and inflammatory responses as well as promoted apoptosis in RA-FLS. Online predictions and dual luciferase reporter gene assays suggested that LINC01197 could bind to miR-150 and further regulate THBS2 expression. LINC01197 promoted THBS2 expression through miR-150 sponging and inactivated the TLR4/NF-κB signaling pathway, thus alleviating RA inflammation. CONCLUSION: The current study suggested that LINC01197 sponged miR-150 to promote THBS2 expression, leading to TLR4/NF-κB inactivation, and ameliorated RA inflammation. These findings may offer new insights into RA treatment.

Dynamic changes in gut microbiota under the influence of smoking and TNF-α-blocker in patients with ankylosing spondylitis.

OBJECTIVES: This study aimed to investigate the relationship among smoking, TNF-α-blocker therapy, and the dynamic changes in gut microbiota in patients with ankylosing spondylitis (AS). METHODS: Using a 16S rRNA sequence, 98 fecal samples of 20 AS patients collected after 0, 1, 3 and 6 months of anti-TNF-α treatment and from 20 matched health controls were examined. The variation in composition, abundance, and diversity of gut microbiota was analyzed. The dynamic effects of smoking and treatment on gut microbiota and therapeutic efficacy in AS patients were studied. RESULTS: The increased relative abundance of microbiota in AS nonsmokers was g_Comamonas and g_Desulfovibrio, while that in AS smokers was g_Actinomyces, g_Collinsella, g_Lachnospiraceae_UCG-008, and g_Paraprevotella. The relative abundance of gut microbiota showed dynamic variation. The improvement rate of ASDAS in AS nonsmokers was higher than that in AS smokers (2.297 vs 1.736) after anti-TNF-α treatment. The ß-diversity of gut microbiota in AS smokers was lower than that in AS nonsmokers and improved with treatment. CONCLUSIONS: Both smoking and TNF-α-blocker had significant effects on the composition, relative abundance, and diversity of gut microbiota in AS patients. The AS smokers characteristically shared g_Collinsella and g_Dorea. The relative abundance of gut microbiota revealed high variability and was in dynamic fluctuation during treatment. The response of gut microbiota to anti-TNF-α treatment was found to be heterogeneous and selective. AS nonsmokers showed a greater improvement rate of ASDAS-CRP with treatment than AS smokers did. The AS smokers showed a lower ß-diversity of gut microbiota, and improved after treatment. Key Points • Characterized the dynamic variation in gut microbiota in AS patients classified as smokers and nonsmokers during treatment with anti-TNF-α. • Confirmed the interaction between smoking, anti-TNF-α therapy, and gut microbiota.

Validation of new classification criteria of rheumatoid arthritis in an international multicentre study.

OBJECTIVES: Early identification of patients with rheumatoid arthritis (RA) is essential to allow prompt therapy. In this study, we aimed to evaluate the performance of the newly proposed ERA criteria, compared to the 1987 ACR and 2010 ACR/EULAR criteria in an international multicentre study. METHODS: A total of 606 patients with disease duration ≤2 years and age ≥16 years who were diagnosed as RA or non-RA were enrolled from China, Sweden and India. The clinical and laboratory parameters were recorded. We compared the sensitivity, specificity, predictive value, likelihood ratio (LR), and the area under the ROC curve (AUC) of three criteria in these cohorts. Concordance between the three criteria was calculated with the Kappa coefficient. RESULTS: Three hundred and twelve RA and 294 non-RA patients were included. The Early Rheumatoid Arthritis (ERA) criteria had significantly higher specificity compared to the 2010 ACR/ EULAR criteria (83.7% vs. 78.2%, p=0.02) and sensitivity were similar (79.2% vs. 78.5%, p=0.883). In comparison with the 1987 ACR criteria, the ERA criteria had higher sensitivity (79.2% vs. 54.5%, p<0.001) but lower specificity (83.7% vs. 89.1%, p<0.001), and the AUC of the ERA criteria (0.878) was comparable to the 2010 ACR/EULAR criteria (0.849) and higher than the 1987 ACR criteria (0.791, p<0.0001). Patients from the three countries, seronegative and very early arthritis cohorts yielded consistent results. CONCLUSIONS: The ERA criteria demonstrate a better performance across ethnics in early RA diagnosis, and is more feasible in daily practice.

Iguratimod dose dependently inhibits the expression of citrullinated proteins and peptidylarginine deiminases 2 and 4 in neutrophils from rheumatoid arthritis patients.

INTRODUCTION: Anti-citrullinated protein antibodies (ACPAs) play an important role in rheumatoid arthritis (RA). Citrullinated proteins (CPs), which are produced by post-translational modification via peptidylarginine deiminase (PAD), are the target antigen of ACPAs and promote the generation thereof. Herein, we investigated whether iguratimod (IGU) affects the generation of CPs via PAD. METHODS: Neutrophils and peripheral blood mononuclear cells (PBMCs) were isolated from three patients diagnosed with RA and treated with various concentrations of IGU, methotrexate (MTX), or dexamethasone (DXM) or without any drugs as a control for 8 h. The levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, and IL-8 in culture supernatants were tested by ELISA. CPs were measured by western blot, and the expression of PAD2 and PAD4 in cells was detected by qRT-PCR and western blot. RESULTS: PAD2 and PAD4 expressions in neutrophils but not in PBMCs were decreased by IGU at both the protein and mRNA levels (P < 0.05). CP expression in neutrophils but not in PBMCs was also inhibited by IGU. The inhibitory effect of IGU was dose-dependent. IGU, MTX, and DXM dose dependently decreased the secretion of TNF-α, IL-1ß, IL-6, and IL-8 in neutrophils and PBMCs (P < 0.05); the inhibitory effect of IGU was not significantly different from that of MTX and DXM. CONCLUSIONS: IGU inhibited the expression of CPs by downregulating PADs in neutrophils from RA patients, and the effect was comparable to that of MTX and DXM at appropriate concentrations. These findings may provide guidance for more appropriate treatment of RA.Key Points• Iguratimod inhibited citrullinated protein expression in neutrophils from rheumatoid arthritis patients similarly to methotrexate and dexamethasone at appropriate concentrations.• The inhibitory effect was mediated by downregulation of peptidylarginine deiminases, providing insight into the mechanism of iguratimod as a treatment for rheumatoid arthritis.• This study may guide rheumatoid arthritis treatment and facilitate identification of other therapeutic targets.

Baseline Interleukin-6 and Erythrocyte Sedimentation Rate Can Predict Clinical Response of TNF Inhibitor Treatment in Patients with Ankylosing Spondylitis.

OBJECTIVE: The objective of this study is to investigate the baseline predictors of clinical response from tumor necrosis factor (TNF) inhibitor within ankylosing spondylitis (AS) patients. METHODS: We selected 60 AS patients and 24 healthy individuals. The interleukin (IL)-1ß, IL-6, IL-17A and TNF-α levels were measured using the cytometric bead array. The receiver operating characteristic curve was used to analyze the cut off values of baseline predictors. A binary logistic regression test was used to investigate the association between baseline predictors and clinical response. RESULTS: At baseline, the IL-1ß, IL-6 and TNF-α level were positively correlated with disease activity. After 12 weeks of treatment, good responders had lower baseline IL-6 level and erythrocyte sedimentation rate (ESR) than non/poor responders. The cut off value of baseline IL-6 level and ESR to predict clinical response of TNF inhibitor treatment were 9.05 pg/mL and 47.00 mm/h, respectively. Binary logistic regression found that baseline IL-6 levels and ESR had an adverse relationship with clinical response, and the combination of IL-6 level and ESR could predict clinical response more effectively. CONCLUSIONS: The baseline IL-6 level and ESR can predict the clinical response of TNF inhibitor treatment within AS patients, which might facilitate the selection and adjustment of medication regimens for subjects.

Evaluation of 12 different assays for detecting ANCA in Chinese patients with GPA and MPA: a multicenter study in China.

OBJECTIVE: Due to lack of comprehensive evaluation for various detection methods for antineutrophil cytoplasmic antibody (ANCA) in Chinese population, we evaluate the diagnostic performance of 12 established analysis methods in Chinese patients having granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA). METHODS: Sera were collected from 209 patients with GPA or MPA and 243 diseases controls from 15 centers. Twelve different reagents were employed for C-ANCA, P-ANCA, myeloperoxidase (MPO)-ANCA, and proteinase 3(PR3)-ANCA detection. The accuracy, sensitivity, and specificity of each method were analyzed. RESULTS: The accuracy of the two indirect immunofluorescence (IIF) and two line immunoassay (LIA) was 0.838 and 0.874, 0.869, and 0.862, respectively. The accuracy of the eight quantitative antigen-specific immunoassays was varied from 0.867 to 0.967. The sensitivity of ANCA-associated vasculitis (AAV) was 0.770 and 0.761 for the two IIF, 0.727 and 0.718 for the two LIAs, respectively. For the eight quantitative antigen-specific immunoassays, the sensitivity varied from 0.79 to 0.967. The specificity was 0.897 and 0.971 for the two IIF, 0.992 and 0.988 for the two LIAs, respectively. For the eight quantitative antigen-specific immunoassays, the specificity of AAV varied from 0.963 to 0.983. CONCLUSION: For Chinese patients suspected of having GPA and MPA, both the first-generation enzyme-linked immunosorbent assay (ELISA) and high-quality antigen-specific immunoassay can be used to detect MPO-ANCA and PR3-ANCA alone, without the combined detection with IIF to have good diagnostic performance. The chemiluminescent immunoassay (CLIA) seems to be a method worth recommending.Key points• Quantitative antigen-specific immunoassays can be used to detect MPO-ANCA and PR3-ANCA without IIF in Chinese.• CLIA has the maximum AUC value and the minimum LR (-) value, which seems to be a method worth recommending.

4-O-methylhonokiol protects against diabetic cardiomyopathy in type 2 diabetic mice by activation of AMPK-mediated cardiac lipid metabolism improvement.

Diabetic cardiomyopathy (DCM) is characterized by increased left ventricular mass and wall thickness, decreased systolic function, reduced ejection fraction (EF) and ultimately heart failure. The 4-O-methylhonokiol (MH) has been isolated mainly from the bark of the root and stem of Magnolia species. In this study, we aimed to elucidate whether MH can effectively prevent DCM in type 2 diabetic (T2D) mice and, if so, whether the protective response of MH is associated with its activation of AMPK-mediated inhibition of lipid accumulation and inflammation. A total number of 40 mice were divided into four groups: Ctrl, Ctrl + MH, T2D, T2D + MH. Five mice from each group were sacrificed after 3-month MH treatment. The remaining animals in each group were kept for additional 3 months without further MH treatment. In T2D mice, the typical DCM symptoms were induced as expected, reflected by decreased ejection fraction and lipotoxic effects inducing lipid accumulation, oxidative stress, inflammatory reactions, and final fibrosis. However, these typical DCM changes were significantly prevented by the MH treatment immediately or 3 months after the 3-month MH treatment, suggesting MH-induced cardiac protection from T2D had a memory effect. Mechanistically, MH cardiac protection from DCM may be associated with its lipid metabolism improvement by the activation of AMPK/CPT1-mediated fatty acid oxidation. In addition, the MH treatment of DCM mice significantly improved their insulin resistance levels by activation of GSK-3ß. These results indicate that the treatment of T2D with MH effectively prevents DCM probably via AMPK-dependent improvement of the lipid metabolism.

Maintenance of effect of duloxetine in Chinese patients with pain due to osteoarthritis: 13-week open-label extension data.

BACKGROUND: The objectives of this study were to assess the maintenance of effect of duloxetine 60 mg once-daily (QD) in Chinese patients with chronic pain due to osteoarthritis (OA) of the knee or hip and to provide additional long-term safety data. METHODS: This was an open-label, extension phase of a randomized, double-blind, placebo-controlled clinical trial. Eligible patients were outpatients who met the American College of Rheumatology clinical and radiographic criteria for OA with a rating ≥4 on Brief Pain Inventory (BPI) 24-h average pain. After completing the 13-week placebo-controlled phase, patients originally assigned to placebo were titrated to duloxetine 60 mg QD (PLA_DLX), whereas patients originally assigned to duloxetine 60 mg QD remained on the same dose of duloxetine (DLX_DLX) for another 13 weeks. The maintenance effect of duloxetine 60 mg QD during the extension phase was evaluated by a 1-sided 97.5% confidence interval (CI) of the baseline-to-endpoint change in the extension phase for patients who took duloxetine and reported ≥30% reduction in BPI average pain at the end of placebo-controlled phase (placebo-controlled phase duloxetine responders). Other BPI severity and interference items, as well as safety and tolerability, were assessed. RESULTS: Of 342 patients entering the extension phase, 162 (97.6%) DLX_DLX-treated patients and 157 (89.2%) PLA_DLX-treated patients completed this phase. Most patients (76.0%) were female. Mean age was 60.6 years. Mean BPI average pain was 5.5 at baseline of the placebo-controlled phase. Among 113 placebo-controlled phase duloxetine responders, mean change in BPI average pain during the extension phase was - 0.59 (from 2.47 to 1.88); the upper bound of the 1-sided 97.5% CI was - 0.31 and less than the pre-specified non-inferiority margin of a 1.5-point increase (p < 0.001). Significant within-group improvements in all BPI items were observed for both PLA_DLX and DLX_DLX groups during the extension phase (all p < 0.01). No deaths or suicide-related events occurred. Seven (4.0%) PLA_DLX-treated patients and no DLX_DLX-treated patients discontinued due to an adverse event. CONCLUSION: The analgesic effect of duloxetine 60 mg QD among treatment responders was maintained for the entire duration of the extension phase. Duloxetine 60 mg QD was well tolerated during the extension phase. TRIAL REGISTRATION: ClinicalTrials.gov identification number NCT01931475 . Registered 29 August 2013.

4-O-methylhonokiol ameliorates type 2 diabetes-induced nephropathy in mice likely by activation of AMPK-mediated fatty acid oxidation and Nrf2-mediated anti-oxidative stress.

Diabetic nephropathy (DN) is one of the most serious long-term complications of type 2 diabetes (T2D). 4-O-methylhonokiol (MH) is one of the biologically active ingredients extracted from the Magnolia stem bark. In this study, we aim to elucidate whether treatment with MH can ameliorate or slow-down progression of DN in a T2D murine model and, if so, whether the protective response of MH correlates with AMPK-associated anti-oxidant and anti-inflammatory effects. To induce T2D, mice were fed normal diet (ND) or high fat diet (HFD) for 3 months to induce insulin resistance, followed by an intraperitoneal injection of STZ to induce hyperglycemia. Both T2D and control mice received gavage containing vehicle or MH once diabetes onset for 3 months. Once completing 3-month MH treatment, five mice from each group were sacrificed as 3 month time-point. The rest mice in each group were sacrificed 3 months later as 6 month time-point. In T2D mice, the typical DN symptoms were induced as expected, reflected by increased proteinuria, renal lipid accumulation and lipotoxic effects inducing oxidative stress, and inflammatory reactions, and final fibrosis. However, these typical DN changes were significantly prevented by MH treatment for 3 months and even at 3 months post-MH withdrawal. Mechanistically, MH renal-protection from DN may be related to lipid metabolic improvement and oxidative stress attenuation along with increases in AMPK/PGC-1α/CPT1B-mediated fatty acid oxidation and Nrf2/SOD2-mediated anti-oxidative stress. Results showed the preventive effect of MH on the renal oxidative stress and inflammation in DN.