Platelet function in rheumatoid arthritis: arthritic and cardiovascular implications

Autoimmune Rheumatic Diseases and Outcomes Following Percutaneous Coronary Intervention: A Systematic Review and Meta-Analysis

Autoimmune Rheumatic Diseases (AIRDs) are associated with increased cardiovascular mortality. However, the post-percutaneous coronary intervention (PCI) outcomes in this population present a research gap, given the limited and discordant findings in existing studies. We conducted a systematic review and meta-analysis to assess the relationship between AIRDs and clinical outcomes after PCI; 9 studies with 7,027,270 patients (126,914 with AIRD, 6,900,356 without AIRD) were included. The AIRD cohort was characterized by an older age, a predominantly female demographic, and a greater prevalence of hypertension and diabetes mellitus. Over a mean follow-up period of 4.6 ± 3.5 years, AIRD patients demonstrated significantly higher odds of all-cause mortality (odds ratio (OR) 1.45, 95% CI: 1.25-1.78, P < .001) and major adverse cardiovascular events (MACE) (OR 1.63, 95% CI: 1.01-2.62, P = .04) compared with non-AIRD patients. Sensitivity analysis using adjusted estimates, confirmed the higher all-cause mortality (hazard ratio 1.32, 95% CI: 1.05-1.64, P = .01). Patients with rheumatoid arthritis had a significantly elevated odds of all-cause mortality (OR 1.50, 95% CI: 1.27-1.77) and MACE (OR 1.18, 95% CI: 1.14-1.21). Our study demonstrated an association between AIRDs and suboptimal long-term outcomes post-PCI. Prospective studies are warranted to explore the risk factors of unfavorable prognoses in patients with AIRDs.

Repurposing the Fibrosis-4 Score in Rheumatoid Arthritis: Data from the ESPOIR Cohort

Background: We aimed to evaluate the value of the Fibrosis-4 (FIB-4) score as a prognostic factor in RA in the prospective ESPOIR cohort. Methods: We included patients from the ESPOIR cohort with a diagnosis of RA according to ACR/EULAR criteria. The formula for the FIB-4 score is as follows: [age (years) × aspartate transaminase level (U/L)]/[platelet count (109/L) × alanine aminotransferase level (U/L)1/2]. We used a linear mixed-effects model with a random effect of patient to account for repeated measures over time. Results: Overall, 647 of the 813 patients included met the ACR/EULAR criteria for RA, with no differential diagnosis during the first 10 years of follow-up. Of these patients, at baseline, 633 had a calculable FIB-4 score. Median FIB-4 score was 0.75 (interquartile range 0.53-0.99). On multivariate analysis, FIB-4 score was not independently associated with progression of Disease Activity Score in 28 joints over 10 years of follow-up, unlike baseline C-reactive protein level and SJC. Baseline FIB-4 score was not associated with the modified Sharp score at 5-year follow-up, unlike age and ACPAs. FIB-4 score was not associated with mortality (hazard ratio 1.1 [95% CI 0.46; 2.8], p = 0.77) or major adverse cardiovascular events (0.46 [0.13; 1.6], p = 0.22) over the 10-year follow-up. No significant change in FIB-4 score over time was related to treatments. Conclusions: The present prospective cohort study did not find a prognostic role of FIB-4 score in RA. Reassuringly, FIB-4 score was not increased with DMARD treatment after 10 years of follow-up.

Association of Red Cell Distribution Width and Mean Platelet Volume With Disease Activity in Rheumatoid Arthritis Patients

BACKGROUND

The inner layer of the synovial joints is the primary target of rheumatoid arthritis, or RA, a chronic systemic inflammatory disorder that is linked to increasing disability, early mortality, and economic hardships. The objective is to determine the association of red cell distribution width (RDW) and mean platelet volume (MPV) with disease activity in RA.

MATERIAL AND METHODS

A retrospective study was conducted between July 2021 and January 2022 in the outpatient rheumatology clinics at Gulab Devi Teaching Hospital. In this study, 100 consecutive participants with a diagnosis of RA fulfilling the ACR/EULAR 2010 classification criteria were enrolled. Patient's records were reviewed for age, gender, length of illness, smoking status, treatment history, current treatment regimen, concomitant medications, rheumatoid factor (RF), anti-cyclic citrulline peptide (anti-CCP) antibodies, and extra-articular manifestations. Laboratory investigations were reviewed for complete blood count including RDW and MPV, ESR, CRP, liver, and renal functions. Disease activity score DAS 28-ESR was used to quantify disease activity. To determine the relationship between different parameters and the RDW and MPV, linear regression research was conducted.

RESULTS

According to the DAS28 score, 12% of patients were in remission, 9% had low, 34% had moderate, and 45% had high disease activity. DAS28 score was 5.01±1.72 (2.45-9.32) and RDW was 16.18±4.42. There was a strong positive correlation (r = 0.653) of RDW with the DAS28 score and it was statistically significant (p<0.001). MPV was 11.30±2.09 fL. There was a moderately positive correlation (r = 0.366) of MPV with the DAS28 score and it was statistically significant (p<0.001).

CONCLUSION

Conclusively, both RDW and MPV are positively related to disease activity in patients with RA. These can be used as a simple tool for assessing disease activity and guiding the treatment.

Structural and Pharmacological Network Focused on MiRNAs Involved in Rheumatoid Arthritis: A Systematic Review

BACKGROUND

Rheumatoid Arthritis (RA) is a chronic autoimmune disease that has a prevalence of over one percent of the world population, causing substantial pain, joint deformity, and functional disability in patients. The identification and measurement of miRNAs are relatively easy to perform. Future studies will corroborate if miRNAs can fulfill their roles as biomarkers with either predictive or diagnostic evaluation of treatment potential and provide actual clinical utility.

METHODS

In the last decade, various advances have been made regarding the identification of the origin and exact functions of miRNAs, allowing us to have a potential use both in the research and clinical fields.

OBJECTIVE

This systematic review aimed to collect, analyze, and improve the current understanding of RA-related miRNAs and their applicability in therapeutics. A bibliographic search of the miRNAs involved in RA was carried out, and through the use of databases, their target genes and small molecules that had some relationship with their expression were searched. The analysis of these data was done through structural network analysis.

RESULTS

During the network analysis, miR-30a, miR-30c, let-7a, miR-144, miR-17-5p, miR-124, miR -23b, miR-23, miR-15a, miR-16 were the most connected, which could be used as possible biomarkers or be candidates for further analysis due to their interaction with other miRNAs and genes.

CONCLUSION

Additionally, this is the first systematic review, in which we proposed that small compounds like toxicants and drugs could have a potential role within RA because they regulate the expression of miRNAs involved in this pathology. Some of these compounds are commonly found as environmental contaminants, and others as drugs. These ideas open a new panorama of understanding RA, proposing possible causes or treatments against this pathology. Therefore, these small molecules would give us some indication of a relationship with RA, thereby helping in seeking causes, treatment, or prevention of this disease.

CONCLUSION

This is the first time it is intended to use structural network analysis to determine possible biomarkers of AR for diagnosis and prognosis through the expression of these miRNAs and their relationship with compounds of daily life.

Artificial intelligence-based preventive, personalized and precision medicine for cardiovascular disease/stroke risk assessment in rheumatoid arthritis patients: a narrative review

The challenges associated with diagnosing and treating cardiovascular disease (CVD)/Stroke in Rheumatoid arthritis (RA) arise from the delayed onset of symptoms. Existing clinical risk scores are inadequate in predicting cardiac events, and conventional risk factors alone do not accurately classify many individuals at risk. Several CVD biomarkers consider the multiple pathways involved in the development of atherosclerosis, which is the primary cause of CVD/Stroke in RA. To enhance the accuracy of CVD/Stroke risk assessment in the RA framework, a proposed approach involves combining genomic-based biomarkers (GBBM) derived from plasma and/or serum samples with innovative non-invasive radiomic-based biomarkers (RBBM), such as measurements of synovial fluid, plaque area, and plaque burden. This review presents two hypotheses: (i) RBBM and GBBM biomarkers exhibit a significant correlation and can precisely detect the severity of CVD/Stroke in RA patients. (ii) Artificial Intelligence (AI)-based preventive, precision, and personalized (aiP3) CVD/Stroke risk AtheroEdge™ model (AtheroPoint™, CA, USA) that utilizes deep learning (DL) to accurately classify the risk of CVD/stroke in RA framework. The authors conducted a comprehensive search using the PRISMA technique, identifying 153 studies that assessed the features/biomarkers of RBBM and GBBM for CVD/Stroke. The study demonstrates how DL models can be integrated into the AtheroEdge™-aiP3 framework to determine the risk of CVD/Stroke in RA patients. The findings of this review suggest that the combination of RBBM with GBBM introduces a new dimension to the assessment of CVD/Stroke risk in the RA framework. Synovial fluid levels that are higher than normal lead to an increase in the plaque burden. Additionally, the review provides recommendations for novel, unbiased, and pruned DL algorithms that can predict CVD/Stroke risk within a RA framework that is preventive, precise, and personalized.

Assessment of prognostic biomarkers in sudden sensorineural hearing loss: A systematic review and meta-analysis

Sudden sensorineural hearing loss (SSNHL) is defined as hearing loss of more than 30 dB in less than 72 h. SSNHL is a frequent complaint and an emergency in otolaryngology. Various biomarkers have been used to determine the prognosis of SSNHL. This systematic review and meta-analysis aims to evaluate the relationship between the different biomarkers and the prognosis of SSNHL. We searched English-language literature up to October 2022 in four databases, including PubMed, Google Scholar, Cochrane, and Science Direct. This search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. This study was reported in the International Prospective Register of Systematic Reviews (PROSPERO) database (ID = CRD42022369538). All studies examining the role of neutrophil to lymphocyte ratio (NLR) concluded that higher NLR is associated with a worse prognosis. The results of studies regarding the relationship between platelet to lymphocyte ratio (PLR) and tumor necrosis factor (TNF) are controversial. Other factors shown to be associated with SSNHL include Glycated hemoglobin (HbA1C), blood glucose, iron levels, serum endocan, salusin-beta, and bone turnover biomarkers. This meta-analysis showed that PLR, NLR, and neutrophils were significantly different between recovered and non-recovered patients. PLR, NLR, and neutrophil count are reliable tools to assess the prognosis of patients with SSNHL.

Anti-arthritic effects of geranium essential oil loaded chitosan nanoparticles in Freund's complete adjuvant induced arthritic rats through down-regulation of inflammatory cytokines

Geranium essential oil (GEO) has been widely used in aromatherapy and traditional medicines. Nanoencapsulation, a novel technique has emerged to overcome the environmental degradation and less oral bioavailability of essential oils. This work was undertaken to encapsulate geranium essential oil in chitosan nanoparticles (GEO-CNPs) by ionic gelation technique and to explore anti-arthritic and anti-inflammatory potential in FCA-induced arthritic model in rats. The GEO was characterized by gas chromatography flame ionization detector (GCFID) and the nanosuspension was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-rays diffraction (XRD). The Wistar albino rats (n = 32) were separated into four groups; Group 1 and 2 were considered as normal and arthritic controls. Group 3 was positive control that received oral celecoxib for 21 days while Group 4 was treated with oral GEO-CNPs after the induction of arthritis. Hind paw ankle joints diameters were weekly measured throughout the study and significant decrease (5.5 ± 0.5 mm) was observed in GEO-CNPs treatment group in comparison to arthritic group (9.17 ± 0.52 mm). Blood samples were drawn at end for evaluation of hematological, biochemical and inflammatory biomarkers. A significant upregulation of red blood cells and hemoglobin while downregulation of white blood cells, interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP) and rheumatoid factor (RF) was observed. Ankles were transected for the histopathological and radiographic examination after animals were sacrificed which confirmed the alleviation of necrosis along cellular infiltration. It was concluded that GEO-CNPs were found to possess excellent therapeutic potential and promising candidates to reduce FCA-induced arthritis.

Association Between Platelet Indices and Preoperative Deep Vein Thrombosis in Elderly Patients Undergoing Total Joint Arthroplasty: A Retrospective Study

To investigate the association between platelet (PLT) indices and preoperative deep vein thrombosis (DVT) in elderly patients undergoing total joint arthroplasty (TJA). A total of 1391 patients were enrolled. We created receiver operator characteristic (ROC) curve using the ratio of PLT indices to DVT before TJA, divided the enrolled patients into groups based on the cut-off value, and then analyzed risk factors for DVT before TJA in the multivariate binary logistic regression analysis. Preoperative DVT occurred in 103 cases. Based on the ROC curve, we determined that the cut-off values for PLT, mean platelet volume (MPV), platelet distribution width (PDW), platelet large cell ratio (P-LCR), and plateletcrit (PCT) were 202 × 10⁹/L, 11.4 fL, 13.2 fL, 34.6%, and 0.228%. And the areas under the curve were 0.606, 0.605, 0.617, 0.616, and 0.598. Multivariate binary regression analysis revealed that the risk of preoperative DVT in TJA patients with PLT≥202 × 10⁹/L, MPV≤11.4 fL, PDW≤13.2 fL, P-LCR≤34.6%, and PCT≥0.228% increased by 2.32 (P < .001, 95% confidence interval [CI] [1.50-3.60]), 1.86 (P < .001, 95% CI [1.22-2.83]), 2.17 (P < .001, 95% CI [1.43-3.31]), 2.27 (P < .001, 95% CI [1.50-3.45]), and 1.76 times (P = .013, 95% CI [1.13-2.76]), respectively. Age, P < .001, odds ratio (OR) = 1.08, 95% CI [1.04-1.11]; corticosteroid use, P = .011, OR = 3.66, 95% CI [1.34-9.96]. We found that increased PLT count and PCT, decreased MPV, PDW, and P-LCR, old age, and corticosteroid use were independent risk factors for preoperative DVT in elderly TJA patients.

Increased serum IL-41 is associated with disease activity in rheumatoid arthritis

BACKGROUND

Interleukin (IL)-41 is upregulated in the synovial tissue of rheumatoid arthritis (RA) patients, but its serum level has not been reported. The present study aimed to determine IL-41 expression in serum from RA patients and to clarify the relationships between IL-41 and disease-related parameters in RA patients.

METHODS

The study included 46 RA patients and 32 healthy controls (HC). Baseline data were obtained by routine physical examinations and immune-related parameters were measured by an automated chemiluminescent immunoassay analyzer. The correlations between IL-41 and disease activity score in 28 joints (DAS28) and serum clinical data were analyzed using the Pearson correlation test.

RESULTS

Serum IL-41 concentrations were higher in RA patients than in HC. Serum IL-41 was positively correlated with DAS28 based on C-reactive protein (DAS28-CRP), CRP, erythrocyte sedimentation rate (ESR), mean platelet volume (MPV), and CRP-to-albumin ratio (CAR) and negatively correlated with platelet count, while rheumatoid factor was significantly correlated with ESR, CRP, and CAR. Receiver operating characteristic curve analysis showed that IL-41 had diagnostic value for RA, especially when combined with MPV.

CONCLUSIONS

The present findings suggest that IL-41 is increased in the serum of RA patients and may be a potential new diagnostic biomarker for RA.

LC-MS/MS-based serum proteomics reveals a distinctive signature in a rheumatoid arthritis mouse model after treatment with mesenchymal stem cells

Mesenchymal stem cells (MSCs) are known to be able to modulate immune responses, possess tissue-protective properties, and exhibit healing capacities with therapeutic potential for various diseases. The ability of MSCs to secrete various cytokines and growth factors provides new insights into autoimmune-diseases such as rheumatoid arthritis (RA). RA is a systemic autoimmune disease that affects the lining of synovial joints, causing stiffness, pain, inflammation, and joint erosion. In recent years, MSCs-based therapies have been widely proposed as promising therapies in the treatment of RA. However, the mechanism involved in disease-specific therapeutic effects of MSCs on RA remains unclear. To clarify the mechanism involved in effects of MSCs on RA, proteomic profiling was performed using an RA mouse model before and after treatment with MSCs. In this study, treatment efficacy of human umbilical cord blood-mesenchymal stem cells (hUCB-MSCs) was confirmed using a type II collagen-induced arthritis (CIA) mouse model. Results of measuring incidence rates of arthritis and clinical arthritis index (CAI) revealed that mice administrated with hUCB-MSCs had a significant reduction in arthritis severity. Proteins that might affect disease progression and therapeutic efficacy of hUCB-MSC were identified through LC-MS/MS analysis using serum samples. In addition, L-1000 analysis was performed for hUCB-MSC culture medium. To analysis data obtained from LC–MS/MS and L-1000, tools such as ExDEGA, MEV, and DAVID GO were used. Results showed that various factors secreted from hUCB-MSCs might play roles in therapeutic effects of MSCs on RA, with platelet activation possibly playing a pivotal role. Results of this study also suggest that SERPINE1 and THBS1 among substances secreted by hUCB-MSC might be key factors that can inhibit platelet activation. This paper is expected to improve our understanding of mechanisms involved in treatment effects of stem cells on rheumatoid arthritis.

Immature platelet fraction in rheumatoid arthritis with interstitial lung disease

BACKGROUND

Platelets have an effect on the hemostatic defense of the lung. Immature platelet fractions (iPF) reflects the number of young platelets containing ribonucleic acid in the circulation and real-time production. Information about their roles in rheumatic diseases is limited and there are no studies on iPF in RA with interstitial lung disease (ILD). Our aim is to investigate the association between the iPF level and occurrence of ILD in RA and the correlation of iPF with disease activity in general or only in RA with ILD.

METHODS

The study included 50 RA patients without ILD, 33 RA patients with ILD, and 30 healthy controls. Demographic data, Disease Activity Score 28 (DAS28), autoantibodies, and iPF were evaluated. ILD was diagnosed by using high-resolution computed tomography with clinical findings and chest X-ray. The samples were analyzed for complete blood count with platelet indices included, on Mindray BC-6800 hematology analyzer, Hamburg, Germany.

RESULTS

iPF levels were higher in RA patients with ILD compared to healthy controls and RA patients without ILD. A weakly positive correlation between DAS28 with iPF was found in all RA patients. iPF levels were found as 2.85 to detect ILD with 66.7% sensitivity and 65% specificity.

CONCLUSIONS

Our results showed that the iPF was detected higher in RA with ILD compared to RA without ILD. iPF, a routine cheap and easy test during hemogram, can provide important information in terms of disease activity and lung involvement in RA.

Microbiota-Derived Propionate Modulates Megakaryopoiesis and Platelet Function

Rheumatoid arthritis (RA) is associated with an increased risk for cardiovascular events driven by abnormal platelet clotting effects. Platelets are produced by megakaryocytes, deriving from megakaryocyte erythrocyte progenitors (MEP) in the bone marrow. Increased megakaryocyte expansion across common autoimmune diseases was shown for RA, systemic lupus erythematosus (SLE) and primary Sjögren’s syndrome (pSS). In this context, we evaluated the role of the microbial-derived short chain fatty acid (SCFA) propionate on hematopoietic progenitors in the collagen induced inflammatory arthritis model (CIA) as we recently showed attenuating effects of preventive propionate treatment on CIA severity. In vivo, propionate treatment starting 21 days post immunization (dpi) reduced the frequency of MEPs in the bone marrow of CIA and naïve mice. Megakaryocytes numbers were reduced but increased the expression of the maturation marker CD61. Consistent with this, functional analysis of platelets showed an upregulated reactivity state following propionate-treatment. This was confirmed by elevated histone 3 acetylation and propionylation as well as by RNAseq analysis in Meg-01 cells. Taken together, we identified a novel nutritional axis that skews platelet formation and function.

Mean Platelet Volume Significantly Decreases in the Remission Period of Systemic Lupus Erythematosus Patients with Renal Involvement

Systemic lupus erythematosus (SLE) is a disease of the immune system with an unknown etiology. It is a unique disease that has a wide range of clinical and laboratory findings according to the organ or system involved and the activity of the disease. Mean platelet volume (MPV) is a simple parameter of the blood and is widely and easily available. It has been evaluated as a sign of inflammation in many kinds of diseases recently. In this study, we retrospectively analyzed the laboratory parameters and clinical features of 36 SLE patients with renal involvement and nephrotic-range proteinuria in the active and remission periods of the disease between 2005 and 2013. We found that the mean MPV in the active disease of the period was statistically significantly higher than in the remission period (8.30 ± 1.09 and 7.88 ± 0.7, respectively, P = 0.007).

Role of Platelets in Osteoarthritis-Updated Systematic Review and Meta-Analysis on the Role of Platelet-Rich Plasma in Osteoarthritis

Platelets are an essential component of hemostasis, with an increasing role in host inflammatory processes in injured tissues. The reaction between receptors and vascular endothelial cells results in the recruitment of platelets in the immune response pathway. The aim of the present review is to describe the role of platelets in osteoarthritis. Platelets induce secretion of biological substances, many of which are key players in the inflammatory response in osteoarthritis. Molecules involved in cartilage degeneration, or being markers of inflammation in osteoarthritis, are cytokines, such as tumor necrosis factor α (TNFα), interleukins (IL), type II collagen, aggrecan, and metalloproteinases. Surprisingly, platelets may also be used as a treatment modality for osteoarthritis. Multiple randomized controlled trials included in our systematic review and meta-analyses prove the effectiveness of platelet-rich plasma (PRP) as a minimally invasive method of pain alleviation in osteoarthritis treatment.

Sarcococca saligna extract attenuates formaldehyde-induced arthritis in Wistar rats via modulation of pro-inflammatory and inflammatory biomarkers

Sarcococca saligna plant is commonly used as traditional therapy for arthritis especially in Asian countries. The current study is designed to explore the anti-arthritic potential of S. saligna aqueous methanolic extract (SSME). Preliminary proximate study and HPLC analysis were performed to investigate the phytochemical characterization and quality control. The safety of the SSME was evaluated by performing an acute oral toxicity study (OECD guidelines 425). The anti-arthritic potential of SSME was explored by in vivo formaldehyde-induced arthritis model. The antiarthritic effect of the SSME was determined through paw diameter, arthritic index, body weight, biochemical and haematological parameters. Radiographic and histopathological studies were also carried out to evaluate the results. qRT-PCR was performed to determine the upregulation and downregulation of anti- and pro-inflammatory cytokines in rats while ELISA was done to determine the concentration of HSP-70, IL-6 and TNF-α in the serum. Results of acute oral toxicity showed no abnormality and mortality. There was no noticeable change in haematological and biochemical parameters. Histopathological examination exhibited the normal structure of vital organs. So, SSME might be safe at a 2000 mg/kg dose, proposing that LD₅₀ was higher than 2000 mg/kg body weight. Gallic acid, catechin, hydroxyl benzoic acid, sinapic acid, caffeic acid, ferulic acid and p-cumaric acid were identified by HPLC. The outcomes of in vivo formaldehyde-induced arthritic model showed that SSME significantly reduced paw inflammation and arthritic index and improved haematological and biochemical parameters. Moreover, the SSME influentially down-regulated the gene expression of IL-1β, IL-6, COX-2, PGE2, TNF-α and NF-κB, and up-regulated the expression of IL-4, and IL-10. The results of the undertaken study suggest that S. saligna have strong anti-arthritic activity supporting its conventional application as the remedy of rheumatoid arthritis.

Dynamic platelet function: A novel biomarker in inflammatory arthritis?

Background

Patients with inflammatory arthritis die prematurely of cardiovascular disease. Inflammation activates platelets. Since treatment of inflammatory arthritis is associated with reduced mortality, and decreased platelet reactivity reduces cardiovascular events, we hypothesised that platelet reactivity as measured by dynamic platelet function (DPF) would be increased in patients with inflammatory arthritis and that reactivity could be reduced with therapeutic intervention.

Objectives

To characterise platelet function using a validated physiological assay in patients with inflammatory arthritis before and after disease improvement.

Methods

22 patients were recruited and treated as per local protocol. DPF was measured at baseline and after clinical improvement. Video microscopy was utilised to measure dynamic platelet behaviour in microliters of blood perfused over von Willebrand factor (VWF) at arterial shear rates (1500 s-1). Motion-analysis software measured the number of platelets interacting with VWF, translocating across VWF, the speed and distance platelets travelled across VWF, and stably adhering to the surface. Platelet parameters at baseline and following improvement were compared using Wilcoxon signed rank test and paired student t-test. Changes in platelet function were correlated to inflammatory disease markers by Pearson Correlation.

Results

18 patients completed the study. Platelet adhesion decreased and platelet motion increased following treatment. Tender joint count correlated with platelet adhesion (Pearson r = 0.616, p≤0.01) while CRP correlated with velocity of platelet movement (Pearson r = 0.563, p≤0.01).

Conclusions

Improvement in clinical markers of inflammation is associated with a corresponding change in platelet function. Given the association between reduced mortality and decreased platelet reactivity our results suggest that an appropriate assay of platelet function could guide future therapy of patients with inflammatory arthritis.

A new decade awaits sticky platelet syndrome: where are we now, how do we manage and what are the complications?

INTRODUCTION

Sticky platelet syndrome is a less known platelet function disorder with a familiar occurrence and likely genetic background. Clinically, it is characterized by an increased risk of venous and arterial thromboembolic events and obstetric placenta-mediated complications. The increased aggregation after low-dose ADP and/or epinephrine is its distinctive laboratory feature. Though described for almost 40 years, several issues regarding its etiology, involved pathomechanisms, genetic background, optimal diagnostic and treatment approach remain controversial.

AREAS COVERED

The work aims to summarize published studies, the actual definition of the syndrome, and point out its drawbacks. A literature search on Medline, Embase, and archives from EHA congresses was performed (terms: 'sticky platelet syndrome' - 'platelet hyperreactivity' - 'platelet hyperaggregability'). The authors added in their unpublished data. The introductory overview of the present understanding is followed by the discussion of the pathophysiologic, diagnostic, and therapeutic problems.

EXPERT OPINION

Despite the growing evidence provided by case reports and series, the lack of robust studies limits the decision-making on diagnostics and management. The diagnostic issues, particularly the standardization of light transmission aggregometry, represent the crucial problem for the broader acceptance of the syndrome.

Methotrexate improves endothelial function in early rheumatoid arthritis patients after 3 months of treatment

Background

Endothelial dysfunction contributes to increased cardiovascular (CV) disease in rheumatoid arthritis (RA). Angiogenic T cells (Tang) are a key regulator of vascular function via their interaction with endothelial progenitor cells (EPCs). Methotrexate (MTX) has been associated to reduced CV disease risk, but its effects on endothelial homeostasis have been poorly explored. We investigated MTX effects on endothelial homeostasis in early, treatment-naïve RA patients.

Methods

Fifteen untreated, early RA patients and matched healthy controls (HC) were enrolled. RA patients with long-standing disease in remission or low disease activity treated with MTX for at least 6 months were selected as controls. Circulating CD28⁺ and CD28^null Tang cell, endothelial microparticle (EMP), EPC and soluble vascular cell adhesion molecule (sVCAM)-1 levels were measured.

Results

Tang percentage was higher in early RA than in HCs and significantly increased after 3-month MTX treatment. Tang cells in RA were characterized by higher percentage of CD28^null and lower CD28-positive cells than HCs. MTX restored a Tang cell phenotype similar to HCs. Altered sVCAM-1, EMP and EPC were restored to levels similar to HCs after a 3-month MTX. Biomarker levels after 3 months of MTX were not different to those of patients with long-standing treatment.

Conclusions

MTX has a positive effect on Tang, sVCAM-1, EPCs and EMPs in RA. Restoration of imbalance between CD28 + and CD28^null Tang by MTX may be one of the mechanisms underlying its favourable effects on endothelial dysfunction. These effects seem to be long-lasting and independent from systemic inflammation reduction, suggesting a direct effect of MTX on the endothelium.

Carotid Artery Pathology in Inflammatory Diseases

There is considerable evidence that patients with inflammatory conditions are at higher risk of developing cardiovascular (CV) disease including carotid artery stenosis. CV disease accounts for 35-50% of the excess mortality in patients with inflammatory diseases such as rheumatoid arthritis, with cerebrovascular disease being the second leading cause of death. We review current evidence regarding the association of inflammatory conditions and specifically carotid artery disease. Clinical epidemiological observations suggest that mechanisms other than classic risk factors may promote accelerated atherogenesis in rheumatoid and other inflammatory arthritis and carotid artery disease is increased in individuals with these conditions. Additional studies to better understand the underlying mechanisms and targeted strategies to mitigate such risk are indicated. For now, lifestyle modifications, aggressive treatment of risk factors and lipid lowering therapy in appropriate individuals is indicated.

The Relationship between Platelet Indices and Ultrasound, Clinical, Laboratory Parameters of Disease Activity in Patients with Rheumatoid Arthritis

(1) Background: A proper assessment of disease activity is crucial for the management of a patient with rheumatoid arthritis (RA). Platelets seem to be involved in joint inflammation pathophysiology. Platelet indices (PIs) are markers of platelet activation, and include platelet count (PC), mean platelet volume (MPV), platelet distribution width (PDW) and plateletcrit (PCT). The purpose of the study was to assess the relationship between PIs and disease activity markers, both systemic (clinical, laboratory) and local (ultrasound, US), in patients with RA; (2) Methods: The study group consisted of 131 consecutive RA patients. The following assessments were performed: joint counts, Disease Activity Score (DAS28), complete blood cell counts, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and US of 24 small joints; (3) Results: Mean values of PIs remained within the normal reference ranges. Values of PC, PCT, PDW were significantly associated with disease activity markers, both clinical (DAS28, joint counts) and laboratory (CRP, ESR). In patients with high disease activity, PC, PCT were significantly higher and PDW lower. PC was positively correlated with Power Doppler US (PDUS) score. In patients with features of RA severity (antibodies positivity, extra-articular manifestations) PC and PCT were positively associated with all US parameters (Grey Scale US, PDUS, Global scores); (4) Conclusions: In patients with RA, PC and PCT may serve as positive disease activity markers and PDW may serve as a negative marker. PIs may be used as reliable, inexpensive markers of RA systemic activity; they may also serve as markers of local inflammation in the joints affected by RA.

Genetic variants associated with platelet count are predictive of human disease and physiological markers

Platelets play an important role in hemostasis and other aspects of vascular biology. We conducted a meta-analysis of platelet count GWAS using data on 536,974 Europeans and identified 577 independent associations. To search for mechanisms through which these variants affect platelets, we applied cis-expression quantitative trait locus, DEPICT and IPA analyses and assessed genetic sharing between platelet count and various traits using polygenic risk scoring. We found genetic sharing between platelet count and counts of other blood cells (except red blood cells), in addition to several other quantitative traits, including markers of cardiovascular, liver and kidney functions, height, and weight. Platelet count polygenic risk score was predictive of myeloproliferative neoplasms, rheumatoid arthritis, ankylosing spondylitis, hypertension, and benign prostate hyperplasia. Taken together, these results advance understanding of diverse aspects of platelet biology and how they affect biological processes in health and disease.

Evgenia Mikaelsdottir et al. report a study of variants associated with platelet count among European individuals where they identify 577 associations. They also report a genetic overlap between platelet count and human diseases, including myeloproliferative neoplasms, rheumatoid arthritis, and hypertension, as well as a genetic overlap between platelet count and various physiological markers.

Clinical Usefulness of Hematologic Indices as Predictive Parameters for Systemic Lupus Erythematosus

OBJECTIVE

This study assessed the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), mean platelet volume, platelet distribution width, and red cell distribution width (RDW) in systemic lupus erythematosus (SLE) patients and their correlation with disease activity.

METHODS

Two hundred eight SLE patients and 205 age- and sex-matched healthy controls were included. Disease activity was assessed using the systemic lupus erythematosus disease activity index 2000, and hematological indices were determined.

RESULTS

Lymphocyte and platelet counts were significantly lower in SLE patients than in the controls, while the NLR, PLR, and RDW were significantly higher (P < .05). In patients with active disease, the neutrophil counts, NLR, and PLR were significantly higher than in those with inactive disease (P < .05), while the lymphocyte count was significantly lower (P < .05). Based on receiver operating characteristic curve analyses, only for lymphocyte count and PLR. The area under curve was significantly higher (P = .001 and P = .053, respectively).

CONCLUSION

PLR can serve as a biomarker for indicating SLE disease activity.

Immature Platelet Fraction in Rheumatoid Arthritis with Interstitial Lung Disease

BACKGROUND

Platelets have an effect on the hemostatic defense of the lung. Immature platelet fractions (iPF) reflects the number of young platelets containing ribonucleic acid in the circulation and real-time production. Information about their roles in rheumatic diseases is limited and there are no studies on iPF in RA with interstitial lung disease (ILD). Our aim is to investigate the association between the iPF level and occurrence of ILD in RA and the correlation of iPF with disease activity in general or only in RA with ILD.

METHODS

The study included 50 RA patients without ILD, 33 RA patients with ILD, and 30 healthy controls. Demographic data, Disease Activity Score 28 (DAS28), autoantibodies, and iPF were evaluated. ILD was diagnosed by using high-resolution computed tomography with clinical findings and chest X-ray. The samples were analyzed for complete blood count with platelet indices included, on Mindray BC-6800 hematology analyzer, Hamburg, Germany.

RESULTS

iPF levels were higher in RA patients with ILD compared to healthy controls and RA patients without ILD. A weakly positive correlation between DAS28 with iPF was found in all RA patients. iPF levels were found as 2.85 to detect ILD with 66.7% sensitivity and 65% specificity.

CONCLUSIONS

Our results showed that the iPF was detected higher in RA with ILD compared to RA without ILD. iPF, a routine cheap and easy test during hemogram, can provide important information in terms of disease activity and lung involvement in RA.

Effect of Biologics on Cardiovascular Inflammation: Mechanistic Insights and Risk Reduction

It is increasingly recognized that atherosclerosis and consequently cardiovascular disease (CVD) are closely linked with inflammatory processes. The latter is in the center of the pathogenic mechanism underlying autoimmune rheumatic diseases (ARD). It follows then, that optimal control of inflammation in ARDs may lead to a decrease of the accompanied CVD risk. Major trials (eg, CANTOS, CIRT), aimed at examining the possible benefits of immunomodulatory treatments in CVD, demonstrated conflicting results. On the other hand, substantial evidence is accumulating about the possible beneficial effects of biologic disease modifying antirheumatic drugs (bDMARDs) in patients with ARDs, particularly those with rheumatoid arthritis (RA). It seems that bDMARDs (some more than others) alter the lipid profile in RA patients but do not adversely affect, in most cases, the TC/HDL ratio. Favorable effects are noted for arterial stiffness and endothelial function. This is reflected in the lower risk for CVD events, seen in observational studies of RA patients treated with bDMARDs. It should be stressed that more data exist for the TNF-inhibitors than for other bDMARDs, such as tocilizumab, abatacept and rituximab. As regards the spondyloarthropathies (SpA), data are less robust. For TNF-inhibitors, effects appear to be on par with those seen in RA but no conclusions can be drawn for newer biologic drugs used in SpA (eg, IL-17 blockers). Finally, there is accumulating evidence for a beneficial effect of immunosuppressive treatment in cardiac inflammation and function in several ARDs. Introduction of newer therapeutic options in clinical practice seem to have a positive impact on CVD in the setting of ARD. This is probably due to better control of inflammation, but direct improvement in vascular pathology is also a valid hypothesis. Most data are derived from observational studies and, therefore, randomized controlled trials are needed to assess the possible favorable effect of bDMARDs on CVD outcomes.

Accelerated Spatial Fibrin Growth and Impaired Contraction of Blood Clots in Patients with Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease associated with thrombotic complications. To elucidate pathogenic mechanisms, hemostatic disorders in RA were correlated with other laboratory and clinical manifestations. Hemostasis was assessed using relatively new complementary tests, the spatial growth of a plasma clot (Thrombodynamics assay), and contraction of whole blood clots. Platelet functionality was assessed with flow cytometry that quantified the expression of P-selectin and the fibrinogen-binding capacity of platelets before and after activation with a thrombin receptor-activating peptide. Parameters of fibrin clot growth and the kinetics of contraction of blood clots were significantly altered in patients with RA compared to the control group. In Thrombodynamics measurements, an increase in the clot growth rate, size, and optical density of plasma clots altogether indicated chronic hypercoagulability. The rate and extent of blood clot contraction in patients with RA was significantly reduced and associated with platelet dysfunction revealed by an impaired response to activation. Changes in the parameters of clot growth and contraction correlated with the laboratory signs of systemic inflammation, including hyperfibrinogenemia. These results confirm the pathogenic role of hemostatic disorders in RA and support the validity of fibrin clot growth and the blood clot contraction assay as indicators of a (pro)thrombotic state.

Cardiovascular Risk of Synthetic, Non-Biologic Disease-Modifying Anti- Rheumatic Drugs (DMARDs)

Patients with rheumatoid diseases have an increased risk of cardiovascular disease (CVD) and CVD-related death compared with the general population. Both the traditional cardiovascular risk factors and systemic inflammation are contributors to this phenomenon. This review examines the available evidence about the effects of synthetic, non-biologic disease-modifying antirheumatic drugs (DMARDs) on CVD risk. This is an important issue for clinicians when deciding on individual treatment plans in patients with rheumatic diseases. Evidence suggests that synthetic, non-biologic DMARDs such as methotrexate, sulfasalazine, hydroxychloroquine, leflunomide and tofacitinib show decreased CVD morbidity and mortality. However, the strongest data in favour of a reduction in CVD events in rheumatoid patients are shown with methotrexate, which has been the focus of most studies. Adequate proof for a favourable effect also exists for hydroxychloroquine. Larger, prospective studies and randomized clinical trials are needed to better characterize the effect of synthetic, non-biologic DMARDs on CVD outcomes in these patients. Design of future studies should include areas with lack of evidence, such as the risk for heart failure, arrhythmias and valvular heart disease. The clinically relevant question whether synthetic, non-biologic DMARDs are inferior to biologic DMARDs in terms of CVD outcomes remains not adequately addressed.

Cardiovascular Consequences of Autoimmune Rheumatic Diseases

The increased risk of cardiovascular disease (CVD) among patients with autoimmune rheumatic diseases such as rheumatoid arthritis, spondyloarthritis and systemic lupus erythematosus has been extensively documented. Sub-clinical atherosclerosis can be assessed using various non-invasive imaging techniques. However, the mechanisms underlying the higher risk of atherosclerotic CVD in patients with autoimmune rheumatic diseases are not fully known, although they seem to include chronic low-grade systemic inflammation leading to prolonged endothelial activation, accompanied by a pro-thrombotic/pro-coagulant and autoantibody state. Furthermore, sub-clinical atherosclerosis is also influenced by other traditional risk factors for CVD. Including the individual components of the metabolic syndrome (MetS: obesity, impaired glucose metabolism, dyslipidemia and high blood pressure), the degree of which is higher in these patients than in controls. The aim of this narrative review is to discuss the CV manifestations and risk factors involved in the increased risk of CVD among patients with autoimmune rheumatic diseases.

Cardiovascular Effects of Biologic Disease-Modifying Anti-Rheumatic Drugs (DMARDs)

The risk of cardiovascular (CV) disease is increased among patients with systemic autoimmune rheumatic diseases and remains an underserved area of medical need. Although traditional risk factors for CV disease, such as hypertension, smoking, dyslipidemia and obesity contribute to endothelial dysfunction in rheumatoid arthritis (RA), they are not enough on their own to explain the observed excess CV risk. Rather, systemic inflammation seems to play a pivotal role in both disease states. Considering the inflammatory process in autoimmune diseases, scientific interest has focused on recently introduced biologic disease-modifying agents (bDMARDS) such as inhibitors of Tumor Necrosis Factor- α (ΤΝF-α), Interleukins -1 (IL-1) and -6 (IL-6). Despite the widespread use of bDMARDS in RA and other chronic autoimmune inflammatory diseases, their precise impact on CV disease and outcome remains to be elucidated, while prospective randomized control trials assessing their impact on hard CV endpoints are scarce. In this review, we summarize current knowledge concerning the effect of bDMARDs on CV outcome and on the risk of developing CV disease in patients with systemic autoimmune rheumatic diseases.

Value of Platelet Distribution Width and Mean Platelet Volume in Disease Activity Score of Rheumatoid Arthritis

Background and Objective

Disease activity score 28 (DAS28) for rheumatoid arthritis (RA) is the commonly used DAS; it relies on clinical parameters that could be subjective. This work aimed to create a more accurate DAS for RA and assess its validity.

Patients and Methods

The study included 98 RA patients and 53 matched controls; they were interviewed, clinically examined, their visual analogue scales (VAS) were reported, and then blood samples were withdrawn for erythrocyte sedimentation rate (ESR), complete blood count (CBC), and C-reactive protein (CRP). Platelet indices (PIs) were obtained from the CBC including Plt (platelet count), mean platelet volume (MPV), platelet distribution width (PDW) and plateletcrit (PCT). DAS28 was calculated for each patient using RheumaHelper mobile software. Minitab Statistical Package^® and SPSS v20 software were used for data analysis.

Results and Conclusions

Results revealed perfect matching between patients and controls as regarding age and gender. ESR, CRP and PDW were significantly higher in patients than controls; also positive correlations were detected among these variables. A new DAS for RA was developed; ESR, CRP, PDW and MPV were the components for this index. Further analyses showed that this new score was significantly higher in patients than controls and correlated with DAS28 of the patients. Furthermore the new score could identify RA patients from healthy subjects (cut off value < -0.79) and stratified RA patients according to their disease activity into low, intermediate, high, or in remission. Conclusively, we developed a more precise, easily obtained new DAS for RA. This new DAS has both diagnostic/prognostic values in patients with RA.

Significance of serum albumin and derived neutrophil-to-lymphocyte ratio score in assessment of disease activity in rheumatoid arthritis patients

Background

Albumin and derived neutrophil to lymphocyte ratio (dNLR) are known biomarkers that can reflect systemic inflammation and it has been hypothesized that combination of both markers in one score (albumin-dNLR score) can be useful in monitoring rheumatoid arthritis (RA) patients. The current study intended to measure albumin -dNLR score in patients with RA in the order to find whether these new biomarkers could reflect the activity of the disease and the articular activity detected by ultrasonography. We measured serum albumin and dNLR in blood samples obtained from 100 RA patients and from 100 apparently healthy controls (HC). Albumin -dNLR score was calculated according to the presence of hypoalbuminemia (≤ 3.76 gm/dl) and/or raised dNLR (>1.37).

Results

RA patients had a significantly elevated dNLR (p< 0.001) and albumin-dNLR score (p< 0.001) compared to their levels in HC, while serum albumin was significantly decreased (p< 0.001) in RA patients than its level in HC. In RA patients, albumin-dNLR score correlated significantly with DAS28 (p< 0.001), erythrocyte sedimentation rate (ESR) (p< 0.001), C-reactive protein (p< 0.001), grey scale (p< 0.001), power Doppler (p< 0.001) and total ultrasound score (p< 0.001). Also, tender joint count, ESR and albumin-dNLR score were significant predictors of DAS28 in multivariate regression analysis.

Conclusions

Our study settled that albumin - dNLR score is increased in RA patients than in healthy subjects. The score correlated well with DAS28, acute phase reactants, and ultrasonographic synovitis scores implying that it could be an easy valuable biomarker to monitor RA disease activity.

Platelets: emerging facilitators of cellular crosstalk in rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disease in which a variety of circulating pro-inflammatory cells and dysregulated molecules are involved in disease aetiology and progression. Platelets are an important cellular element in the circulation that can bind several dysregulated molecules (such as collagen, thrombin and fibrinogen) that are present both in the synovium and the circulation of patients with RA. Platelets not only respond to dysregulated molecules in their environment but also transport and express their own inflammatory mediators, and serve as regulators at the boundary between haemostasis and immunity. Activated platelets also produce microparticles, which further convey signalling molecules and receptors to the synovium and circulation, thereby positioning these platelet-derived particles as strategic regulators of inflammation. These diverse functions come together to make platelets facilitators of cellular crosstalk in RA. Thus, the receptor functions, ligand binding potential and dysregulated signalling pathways in platelets are becoming increasingly important for treatment in RA. This Review aims to highlight the role of platelets in RA and the need to closely examine platelets as health indicators when designing effective pharmaceutical targets in this disease.

Meroterpenoid-Rich Fraction of the Ethanol Extract of Sargassum Serratifolium Suppresses Collagen-Induced Rheumatoid Arthritis in DBA/1J Mice Via Inhibition of Nuclear Factor κB Activation

SCOPE

Rheumatoid arthritis (RA) is an autoimmune disorder related to the inflammation of cartilage due to the infiltration of inflammatory cells. Sargassum serratifolium, a brown alga, possesses strong anti-inflammatory activities.

METHODS AND RESULTS

The effect of meroterpenoid-rich fraction from the ethanol extract of S. serratifolium (MES) on RA and its underlying mechanisms on the inhibition of RA using a collagen-induced arthritis (CIA) mouse model are examined. The results show that MES ameliorates paw swelling and reduces the arthritis score. MES considerably decreases the secretion of pro-inflammatory cytokines in the serum and joint tissue of mice. Histopathological analysis demonstrates that MES strongly inhibited bone damage and inflammatory cell intrusion in the joint tissue. The expression of inflammatory enzymes and adhesion molecules is significantly inhibited in the serum and joint tissue of MES-fed mice. In addition, MES downregulates the nuclear factor κB (NF-κB) signaling pathway by suppressing the phosphorylation of protein kinase B, c-Jun N-terminal kinase, and p38 mitogen-activated protein kinases.

CONCLUSIONS

MES supplementation remarkably reduces inflammatory response in CIA mouse model. These results indicate that MES can be used as a pharmaceutical agent against RA.

Risk of venous thromboembolism in patients with psoriatic arthritis, psoriasis and rheumatoid arthritis: a general population-based cohort study

Aims

To determine the risk of venous thromboembolism (VTE) defined as the combined endpoint of deep venous thrombosis (DVT) and pulmonary embolism (PE) among patients with psoriatic arthritis (PsA), psoriasis and rheumatoid arthritis (RA) compared with population controls.

Methods and results

A cohort study was conducted in a primary care medical record database in the UK with data from 1994-2014 among patients with PsA, RA, or psoriasis. Cox proportional hazards models were used to calculate the relative hazards for DVT, PE, and VTE. An interaction with disease modifying anti-rheumatic drugs (DMARD) was hypothesized a priori and was significant. Patients with PsA (n = 12 084), RA (n = 51 762), psoriasis (n = 194 288) and controls (n = 1 225 571) matched on general practice and start date were identified. Patients with RA (with and without a DMARD prescription) and patients with mild psoriasis had significantly elevated risks of VTE (HR 1.35, 1.29, and 1.07, respectively) after adjusting for traditional risk factors. Severe psoriasis and PsA prescribed a DMARD had an elevated but not statistically significant risk for VTE. Findings were similar for DVT. The age-and-sex-adjusted risk of PE was elevated in RA, severe psoriasis and PsA patients prescribed a DMARD.

Conclusion

While systemic inflammation is a risk factor for VTE, the risk of VTE compared with controls is different among patients with three different inflammatory disorders: RA, PsA, and psoriasis.

Misunderstandings Between Platelets and Neutrophils Build in Chronic Inflammation

Regulated hemostasis, inflammation and innate immunity entail extensive interactions between platelets and neutrophils. Under physiological conditions, vascular inflammation offers a template for the establishment of effective intravascular immunity, with platelets providing neutrophils with an array of signals that increase their activation threshold, thus limiting collateral damage to tissues and promoting termination of the inflammatory response. By contrast, persistent systemic inflammation as observed in immune-mediated diseases, such as systemic vasculitides, systemic sclerosis, systemic lupus erythematosus or rheumatoid arthritis is characterized by platelet and neutrophil reciprocal activation, which ultimately culminates in the generation of thrombo-inflammatory lesions, fostering vascular injury and organ damage. Here, we discuss recent evidence regarding the multifaceted aspects of platelet-neutrophil interactions from bone marrow precursors to shed microparticles. Moreover, we analyse shared and disease-specific events due to an aberrant deployment of these interactions in human diseases. To restore communications between the pillars of the immune-hemostatic continuum constitutes a fascinating challenge for the near future.

Characterization of cell-derived microparticles in synovial fluid and plasma of patients with rheumatoid arthritis

Microparticles (MP) are proposed to play a role in the pathogenesis of rheumatoid arthritis (RA). This study aimed to profile cell lineage-specific MP in patients with RA, osteoarthritis (OA), and healthy controls (HC) in synovial fluid and circulation. Patients with RA (n = 40), OA (n = 30) and HC (n = 33) were included. Cell-free synovial fluid (SF) and platelet-poor plasma samples were stained with annexin V APC and antibodies against CD45, CD20, CD14, CD4, CD8, CD66b, and CD61 for multicolor flow cytometry. Mann-Whitney U test/unpaired T test was used to assess intergroup differences among RA and OA SF and clinical, serological phenotypes of RA based on normality distribution; Kruskal-Wallis test with Dunn's multiple comparisons for comparing plasma MPs among RA, OA, and HC. Correlation between MP proportions and disease parameters was assessed by Spearman's correlation. The proportion of annexin V⁺ MP in SF of patients with RA [5 (6.35)] [median (IQR)] was higher compared to OA [1.8 (1.35), p < 0.001] and plasma of patients with RA [3.45 (5.63)] compared to OA [1.85 (1.4)] and HC [0.9 (1.1), p < 0.001]. Leukocyte-derived [0.85 (1.17)], granulocyte-derived [0.4 (2.05)], monocyte-derived [0.4 (0.4)], and T cell-derived MP [CD4⁺ - 0.1 (0.1); CD8⁺ - 0.1(0.1)] were higher in RA SF (p < 0.001). Platelet-derived MP (PMP) were the major fraction [1.5 (4.23), p < 0.001] in RA plasma. Leukocyte-derived MP were higher in RA plasma [0.1 (0.2); p < 0.001) than OA and HC. Annexin V⁺ MP and PMP were higher in the SF of RA with extra-articular manifestations (n = 15), as compared to those without (n = 25) (p = 0.02; p < 0.01, respectively). High SF granulocyte-derived MP were observed in patients with established RA (n = 24), ACPA-positive RA (n = 32) compared to their negative counterparts (p = 0.03; p = 0.02, respectively). Our observations of higher proportions of cell-derived MP in the plasma and synovial fluid of DMARD-naïve RA patients, their clinical and serological phenotypes suggest their role in dynamic cross talk between the joint and systemic circulation, disease pathology, and progression.

The Platelet-to-Lymphocyte Ratio as an Inflammatory Marker in Rheumatic Diseases

The platelet-to-lymphocyte ratio (PLR) has emerged as an informative marker revealing shifts in platelet and lymphocyte counts due to acute inflammatory and prothrombotic states. PLR has been extensively examined in neoplastic diseases accompanied by immune suppression and thrombosis, which can be predicted by combined blood cell counts and their ratios. Several large observational studies have demonstrated the value of shifts in PLR in evaluating the severity of systemic inflammation and predicting infections and other comorbidities, in inflammatory rheumatic diseases. The value of PLR as an inflammatory marker increases when its fluctuations are interpreted along with other complementary hematologic indices, particularly the neutrophil-to-lymphocyte ratio (NLR), which provides additional information about the disease activity, presence of neutrophilic inflammation, infectious complications, and severe organ damage in systemic lupus erythematosus. PLR and NLR have high predictive value in rheumatic diseases with predominantly neutrophilic inflammation (e.g., Behçet disease and familial Mediterranean fever). High PLR, along with elevated platelet count, is potentially useful in diagnosing some systemic vasculitides, particularly giant-cell arteritis. A few longitudinal studies on rheumatic diseases have demonstrated a decrease in PLR in response to anti-inflammatory therapies. The main limitations of PLR studies are preanalytical faults, inadequate standardization of laboratory measurements, and inappropriate subject selection. Nonetheless, accumulating evidence suggests that PLR can provide valuable information to clinicians who encounter multisystem manifestations of rheumatic diseases, which are reflected in shifts in platelet, lymphocyte, neutrophil, or monocyte counts. Interpretation of PLR combined with complementary hematologic indices is advisable to more accurately diagnose inflammatory rheumatic diseases and predict related comorbidities.

The in vitro effect of antirheumatic drugs on platelet function

Several antirheumatic drugs lower the cardiovascular risk among rheumatoid arthritis patients. It is, however, unknown whether inhibition of platelet function contributes to this risk reduction. Only few studies have investigated the potential role of platelets as a target of antirheumatic drugs. In this study, platelet function was tested in vitro in samples from 24 healthy individuals spiked with antirheumatic drugs in clinically relevant concentrations or vehicle. Platelet aggregation was tested with 96-well light transmission aggregometry (LTA), and when an effect ≥20% compared to vehicle was observed, flow cytometric platelet aggregation and activation were evaluated and closure time was measured by Platelet Function Analyzer (PFA-200). When evaluated by LTA, teriflunomide (the active metabolite of leflunomide), tocilizumab, and prednisolone reduced ADP- and collagen-induced platelet aggregation ≥20%, while adalimumab increased TRAP-induced platelet aggregation ≥20%. Using flow cytometry, agonist-induced platelet aggregation with teriflunomide or vehicle was mean ± standard deviation (SD); 30.7% ± 5.8 vs. 41.7% ± 6.5, p = 0.02 using ADP, and 34.7% ± 13.9 vs. 55.8% ± 3.9, p = 0.01 using collagen. Results indicate that teriflunomide, prednisolone, and tocilizumab inhibit, and adalimumab increases platelet aggregation. The study suggests that the majority of antirheumatic drugs mainly reduced cardiovascular risk through indirect effects (e.g., reducing inflammation).

Rac1 regulates platelet microparticles formation and rheumatoid arthritis deterioration

Platelets play important roles in blood clotting, hemostasis and wound repair, while more and more research show that platelets also have significant contributions in the process of inflammation. Rheumatoid arthritis is a chronic systemic inflammatory autoimmune disease. Platelet microparticles, which are membrane vesicles shed by activated platelets, are reported to amplify inflammation in Rheumatoid arthritis. Here we show that either platelet-specific deletion of Rac1 (Rac1^-/-) or Rac1-specific inhibitor NSC23766 dramatically inhibit platelet-derived microparticles formation. As we all know, collagen-induced arthritis (CIA) mouse model is the most common autoimmune model of rheumatoid arthritis. Interestingly, NSC23766 alleviated the process of collagen-induced arthritis of DBA mice in vivo, including the reduced hind paw thickness and ankle stiffness, the reduction of arthritic scores and incidence of arthritis. Our work also found that NSC23766-treated CIA mouse spleen is less swollen and contains less enlarged white pulp than PBS control. The histological analysis shows that NSC23766-treated but not solvent control improve the cartilage erosion symptom in the joint of CIA mouse. Interestingly, platelet microparticles in the peripheral blood of NSC23766-treated CIA mice were decreased significantly compared with PBS-treated CIA mice. In conclusion, our work demonstrated that Rac1 inhibition alleviates collagen-induced arthritis through the decrease of platelet microparticles' release. In short, Rac1 aggravate the rheumatoid arthritis deterioration through the regulation of platelet microparticles formation.

Synergistic enhancement and hepatoprotective effect of combination of total phenolic extracts of Citrus aurantium L. and methotrexate for treatment of rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune inflammatory disorder characterized by joint destruction and bone damage. Methotrexate (MTX) is recommended as the first-line disease-modifying agent for the treatment of RA. However, the clinical efficacy of MTX is limited due to its low response and side effects, especially hepatotoxicity. Total phenolic extracts of Citrus aurantium L. (TPE-CA) are rich in dietary bioactive flavonoids, which show beneficial effects on liver health and are regarded as therapeutic tools against inflammatory diseases. In this study, the efficacy of MTX, alone or in combination with TPE-CA, for the treatment of collagen-induced arthritis and protection against hepatic injury in rats was investigated. TPE-CA and MTX combination effectively reduced the inflammatory symptoms and joint damage by inhibiting the NF-κB pathway. Moreover, TPE-CA significantly ameliorated MTX-induced chronic hepatic injury by enhancing antioxidant enzymes activities, suppressing hepatic cytochrome P450 2E1 expression, and modulating the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 pathway. This combination regimen not only provided synergistic enhancement but also exhibited hepatoprotective effect against chemically induced chronic hepatotoxicity. This could be an alternative strategy to improve the low response of MTX in RA treatment.

Platelet to lymphocyte ratio is associated with the current activity of ANCA-associated vasculitis at diagnosis: a retrospective monocentric study

Platelet to lymphocyte ratio (PLR) has been introduced as a useful index to estimate the current inflammatory burdens in various diseases. In this study, we investigate whether PLR is associated with the severity of ANCA-associated vasculitis (AAV). We retrospectively reviewed the medical records of 163 patients with AAV, collected clinical, laboratory and radiological data and calculated Birmingham vasculitis activity score (BVAS). We defined the lower limit of the highest tertile of BVAS as the cut-off for severe AAV (BVAS ≥ 16). The optimal cut-off of PLR for severe AAV was set as 272.0. The odds ratio (OR) of PLR for severe AAV was assessed using the univariable and multivariable logistic regression analyses. The median age at diagnosis was 58.0 years and 51 patients (31.3%) were men. Patients with severe AAV exhibited higher rate of ANCA positivity and higher blood urea nitrogen (BUN), creatinine (Cr), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) than those without. Patients with severe AAV exhibited significantly increased median PLR compared to those without (299.3 vs. 184.0). In the univariable binary logistic regression analysis, BUN ≥ 17.45 mg/dL (OR 3.730), Cr ≥ 1.12 mg/dL (OR 3.519), ESR ≥ 83.5 mm/h (OR 2.785), CRP ≥ 20.0 mg/L (OR 2.612), PLR ≥ 272.0 (OR 4.231) and ANCA positivity (OR 2.306) were associated with severe AAV. In the multivariable binary logistic regression analysis, only PLR ≥ 272.0 was an independent predictor of severe AAV at diagnosis (OR 2.734, 95% CI 1.247, 5.993). In conclusion, PLR at diagnosis is associated with the current activity of vasculitis in AAV patients.

Effect of Sanhuangyilong decoction plus methotrexate on tumor necrosis factor alpha and interferon gamma in serum and synovial fluid in rheumatoid arthritis patients with symptom pattern of damp heat obstruction

OBJECTIVE

To investigate the effect of Sanhuangyilong decoction plus methotrexate (MTX) on Interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α) in the serum and synovial fluid of rheumatoid arthritis (RA) patients with damp-heat-obstruction symptom pattern, Sanhuangyilong decoction and the role of TNF-α and IFN-γ in the development of RA.

METHODS

RA inpatients with damp-heat-obstruction symptom pattern (partly with knee joint effusion) were selected as the research subjects. Before the treatment, healthy subjects and osteoarthritis (OA) patients with knee joint effusion were assigned to the serum control group and the synovial fluid control group, respectively; during the treatment, RA patients with damp-heat-obstruction symptom pattern were divided into two groups: one is combined group that was administered Sanhuangyilong decoction plus MTX; the other group was MTX group that received MTX only. The expression levels of TNF-α and IFN-γ in the serum and synovial fluid were measured with enzyme-linked immunosorbent assay (ELISA) before and after the treatment, and the peripheral blood levels of erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and disease activity score in 28 joints (DAS28) were determined.

RESULTS

Before treatment, the serum levels of TNF-α and IFN-γ in the RA patients with dampheat- obstruction symptom pattern were higher than those in healthy control group (P < 0.05).The expression levels of TNF-α and IFN-γ in the synovial fluid of the RA patients were higher than those in the serum of the RA patients (P < 0.05). The expression levels of TNF-α and IFN-γ in the synovial fluid of the RA patients were higher than those of the synovial fluid of the osteoarthritis patients (P < 0.05). The expression of TNF-α and IFN-γ in the serum and synovial fluid of the RA patients had no correlation with the inflammatory activity index ESR, CRP, or DAS28 (P > 0.05). After 2 weeks of treatment, the expression level of TNF-α and IFN-γ in the combined group had increased, although the difference was not statistically significant (P > 0.05); in contrast, ESR, CRP, and DAS28 decreased, and the difference was statistically significant (P < 0.01). After 4 weeks of therapy, TNF-alpha and IFN-γ, ESR, CRP, and DAS28 in the combined group decreased compared with the before-treatment levels (P < 0.01). After 2 w of treatment, the differences in the TNF-α and IFN-γ expression levels in the combined group were not statistically significant (P > 0.05) compared with that in the MTX group, although there were statistically significant differences in the ESR, CRP, and DAS28 (P < 0.05). After 4 weeks of treatment, differences in TNF-α, IFN-γ, ESR, CRP, and DAS28 in the combined group compared with MTX group were statistically significant (P < 0.01).

CONCLUSION

TNF-α and IFN-γ might be involved in the development of RA. The RA patients with damp-heat-obstruction symptom pattern show better benefits from the treatment of Sanhuangyilong decoction plus MTX, and the treatment is superior to that of using MTX only.

Modulatory effect of eugenol on arginase, nucleotidase, and adenosine deaminase activities of platelets in a carrageenan-induced arthritis rat model: A possible anti-arthritic mechanism of eugenol

This study investigated the effect of eugenol on arginase, nucleotidase and adenosine deaminase activities in platelets of carrageenan-induced arthritic rat model to explain a possible anti-arthritic mechanism of eugenol. Fifty adult female rats (140-250 g) were divided into ten (10) groups (n = 5). Group I received oral administration of corn oil, group II received 2.50 mg/kg of eugenol, group III and IV rats received oral administration of 5.0 and 10.0 mg/kg of eugenol respectively, group V received 0.20 mg/kg of dexamethasone orally, group VI rats was injected with 1% carrageenan (arthritic rats) and received saline solution orally (arthritic control rat group), group VII, VIII and IX: arthritic rats received 2.50, 5.0 or 10 mg/kg of eugenol orally respectively, group X: arthritic rats was administered with 0.20 mg/kg of dexamethasone orally. The animals were treated for 21 days, thereafter, tibiofemoral histological examination, thiobabituric acid reactive substances level, arginase, nucleoside triphosphate diphosphohydrolase, 5´-nucleotidase and adenosine deaminase activities were assessed. Tibiofemoral histological examination result showed that infiltration of inflammatory cells was significantly decreased with an increase in eugenol dose. Activities of arginase, adenosine triphosphate and adenosine monophosphate hydrolyses were significantly decreased while adenosine diphosphate hydrolysis and adenosine deaminase activities were significantly increased in arthritic rat groups administered with different doses of eugenol. Therefore, eugenol might be a natural complement and alternative promising anti-arthritic agent. These possible anti-arthritic mechanisms may be partly through the modulation of arginase and adenosine nucleotides hydrolyzing enzyme activities as well as the antioxidative action of eugenol.

A Microdialysis in Adjuvant Arthritic Rats for Pharmacokinetics⁻Pharmacodynamics Modeling Study of Geniposide with Determination of Drug Concentration and Efficacy Levels in Dialysate

Microdialysis, a sampling method for pharmacokinetics–pharmacodynamics (PK–PD) modeling in preclinical and clinical studies, is a convenient in vivo sampling technique. Geniposide (GE), an iridoid glycoside compound, is the major active ingredient of Gardenia jasminoides Ellis fruit which has an anti-inflammatory effect. In this study, an articular cavity microdialysis sampling system for adjuvant arthritic (AA) rats was established to study the effect of GE on the release of prostaglandin E₂ (PGE₂) in AA rats induced by Freund’s complete adjuvant (FCA). An UHPLC-MS/MS method was developed to determine the concentrations of GE and PGE₂ in the dialysate. Through the determination of drug concentrations and PGE₂ efficacy levels in the dialysate, the developed methods were successfully applied to set up concentration–time and effect–time profiles followed by PK–PD modeling of GE’s effect on decreasing PGE₂ release after oral administration of GE. The effect was well described by the developed PK–PD modeling, indicating that GE may play an anti-inflammatory role via decreasing AA-induced elevated PGE₂ levels. In the selection of suitable endogenous small molecules as effect markers, the establishment of AA rat joint-cavity microdialysis is an attractive technique for rational PK–PD studies.

From blood coagulation to innate and adaptive immunity: the role of platelets in the physiology and pathology of autoimmune disorders

Thrombosis and cardiovascular complications are common manifestations of a variety of pathological conditions, including infections and chronic inflammatory diseases. Hence, there is great interest in determining the hitherto unforeseen immune role of the main blood coagulation executor-the platelet. Platelets store and release a plethora of immunoactive molecules, generate microparticles, and interact with cells classically belonging to the immune system. The observed effects of platelet involvement in immune processes, especially in autoimmune diseases, are conflicting-from inciting inflammation to mediating its resolution. An in-depth understanding of the role of platelets in inflammation and immunity could open new therapeutic pathways for patients with autoimmune disorders. This review aims to summarize the current knowledge on the role of platelets in the patomechanisms of autoimmune disorders and suggests directions for future research.

The role of platelets in autoimmunity, vasculopathy, and fibrosis: Implications for systemic sclerosis

INTRODUCTION

Systemic sclerosis (SSc) is an autoimmune disease characterized by vasculopathy, autoimmunity, and widespread dermal and visceral fibrosis. This article summarizes the current knowledge about the potential contribution of platelets in the disease process and the rationale of targeting platelets as an adjunct treatment for SSc.

METHODS

We performed an electronic search (Medline) using the keywords platelets, systemic sclerosis, autoimmunity, fibrosis, Raynaud, and pulmonary arterial hypertension.

RESULTS

The link that connects vasculopathy, autoimmunity, and fibrosis in SSc remains obscure. Experimental data suggest that platelets are not solely cell fragments regulating hemostasis but they have a pleiotropic role in several biologic processes including immune regulation, vasculopathy, fibrosis, and all key features of SSc. Platelets interplay with the impaired endothelium, can interact with immune cells, and they are storages of bioactive molecules involved in tissue injury and remodeling. The potential role of platelets in the pathogenesis of SSc is further supported by experimental data in animal models of SSc. Platelet-derived serotonin represents a novel target in SSc and serotonin blockade is currently being tested in clinical trials.

CONCLUSION

Platelets may be actively involved in the pathogenesis of SSc by activating immune responses and facilitating the fibrotic process. However, definite conclusions cannot be drawn until more data from both basic and clinical research are available.