Effect of therapeutic inhibition of TNF on circulating endothelial progenitor cells in patients with rheumatoid arthritis

Could endothelial progenitor cells complement the diagnosis of inflammatory arthritis? A systematic review and meta-analysis

The objective of this meta-analysis was to systematically review existing evidence and evaluate variations in levels of circulating endothelial progenitor cells (EPCs) among individuals with psoriatic arthritis (PsA), juvenile idiopathic arthritis (JIA), and rheumatoid arthritis (RA). Relevant studies were identified through database searches, and 20 records were enrolled. We used the fixed-effect model or random-effect model to estimate the pooled standardized mean difference (SMD) with 95% confidence intervals (CIs) in circulating EPC levels between inflammatory arthritis patients and controls. The results showed that circulating EPC levels differed among subtypes of inflammatory arthritis, with significantly lower levels in patients with RA (SMD = -0.848, 95% CI = -1.474 to -0.221, p = 0.008) and PsA (SMD = -0.791, 95% CI = -1.136 to -0.446, p < 0.001). However, no statistically significant difference was found in circulating EPC levels between patients with JIA and controls (SMD = -1.160, 95% CI = -2.578 to 0.259, p = 0.109). Subgroup analyses suggested that in patients with RA, circulating EPC levels were influenced by age, disease activity, and duration. Although many studies have investigated circulating EPC levels in patients with inflammatory arthritis, the results have been inconsistent. This meta-analysis offers a comprehensive overview of the existing evidence and emphasizes the association between levels of circulating EPCs and various types of arthritis. However, further research is needed to determine the specific mechanisms underlying the observed differences in EPC levels in different types of arthritis and to establish the clinical utility of this biomarker.

Endothelial Progenitor Cells in Autoimmune Disorders

Circulating endothelial progenitor cells (EPCs) were first described in 1997 by Asahara et al. as "putative endothelial cells" from human peripheral blood. The study of endothelial progenitors is also intensifying in several pathologies associated with endothelial damage, including diabetes, myocardial infarction, sepsis, pulmonary arterial hypertension, obstructive bronchopneumopathy and transplantation. EPCs have been studied in several autoimmune diseases with endothelial involvement such as systemic lupus erythematosus, thrombotic thrombocytopenic purpura, antineutrophil cytoplasmic antibodies, vasculitis, rheumatoid arthritis, Goujerot-Sjögren and antiphospholipid syndrome. Factors involved in endothelial damage are due to overexpression of pro-inflammatory cytokines and/or autoantibodies. Management of these pathologies, particularly the long-term use of glucocorticoids and methotrexate, promote atherosclerosis. A lack of standardized assessment of the number and function of EPCs represents a serious challenge for the use of EPCs as prognostic markers of cardiovascular diseases (CVD). The objective of this review was to describe EPCs, their properties and their involvement in several autoimmune diseases.

Vascular effects of biologic and targeted synthetic antirheumatic drugs approved for rheumatoid arthritis: a systematic review

BACKGROUND

Rheumatoid arthritis (RA) increases the risk of cardiovascular disease (CVD), with inflammation playing a key role. Biologic and targeted synthetic drugs used to treat RA can induce systemic immunomodulation and may have pleiotropic effects on vascular function, making it crucial to investigate their impact on CVD risk in RA patients.

METHODS

A systematic review of the literature was conducted to investigate the impact of biologic and targeted synthetic treatments approved for RA on various cardiovascular markers, including endothelial function, arterial stiffness, and subclinical atherosclerosis. Our analysis included a search of the MedLine (via PubMed) and Web of Science databases using a pre-determined search strategy. We conducted a narrative synthesis of the included studies due to heterogeneity in study design and outcome measures.

RESULTS

From an initial pool of 647 records, we excluded 327 studies based on their titles and abstracts, and we selected 182 studies for final examination. Ultimately, 58 articles met our inclusion criteria and were included in our systematic review. Our analysis of these studies revealed a positive effect of biologic and targeted synthetic therapies on vascular dysfunction associated with RA. However, the impact of these treatments on subclinical atherosclerosis was inconsistent.

CONCLUSION

Overall, our systematic review provides important insights into the potential cardiovascular benefits of biologic and targeted synthetic treatments for RA by a still unknown mechanism. These findings can inform clinical practice and contribute to our understanding of their possible effects on early vascular pathology. Key Points • Great heterogeneity of methods are used to evaluate the endothelial function and arterial stiffness in patients with RA on biologic and targeted synthetic antirheumatic drugs. • Most studies have shown a considerable improvement in endothelial function and arterial stiffness with TNFi, despite some studies reporting only transient or no improvement. • Anakinra and tocilizumab may have a beneficial effect on vascular function and endothelial injury, as indicated by increased FMD, coronary flow reserve, and reduced levels of biomarkers of endothelial function, while the overall impact of JAKi and rituximab remains inconclusive based on the reviewed studies. • To fully comprehend the distinctions between biologic therapies, more long-term, well-designed clinical trials are necessary using a homogeneous methodology.

Relevance of circulating markers of endothelial activation for cardiovascular risk assessment in rheumatoid arthritis: a narrative review

Rheumatoid arthritis (RA) is associated with excessive cardiovascular mortality secondary to premature atherosclerosis, in which endothelial activation (EA) plays a central role. EA is characterized by loss of vascular integrity, expression of leucocyte adhesion molecules, transition from antithrombotic to prothrombotic phenotype, cytokines production, shedding of membrane microparticles and recruitment of endothelial progenitor cells. As EA is an early event in atherogenesis, circulating markers of EA are putative markers of vascular pathology and cardiovascular (CV) risk. After a presentation of biology of EA, the present review analyzed the available data regarding changes in EA markers in RA in link with the vascular pathology and CV events, discussed their relevance as biomarkers of CV risk and proposed future directions.

Cardiovascular Risk Assessment in Rheumatoid Arthritis: Accelerated Atherosclerosis, New Biomarkers, and the Effects of Biological Therapy

Rheumatoid arthritis (RA), one of the most common of the chronic inflammatory autoimmune diseases (CIADs), is recognized as an independent cardiovascular risk factor. Traditional risk factors such as smoking, arterial hypertension, dyslipidemia, insulin resistance, and obesity are frequently found in RA. Given the increased risk of mortality and morbidity associated with cardiovascular disease (CVD) in RA patients, screening for risk factors is important. Moreover, there is a need to identify potential predictors of subclinical atherosclerosis. Recent studies have shown that markers such as serum homocysteine, asymmetric dimethylarginine, or carotid intima-media thickness (cIMT) are correlated with cardiovascular risk. Although RA presents a cardiovascular risk comparable to that of diabetes, it is not managed as well in terms of acute cardiovascular events. The introduction of biological therapy has opened new perspectives in the understanding of this pathology, confirming the involvement and importance of the inflammatory markers, cytokines, and the immune system. In addition to effects in inducing remission and slowing disease progression, most biologics have demonstrated efficacy in reducing the risk of major cardiovascular events. Some studies have also been conducted in patients without RA, with similar results. However, early detection of atherosclerosis and the use of targeted therapies are the cornerstone for reducing cardiovascular risk in RA patients.

The Effect of TNF-α on CHD and the Relationship between TNF-α Antagonist and CHD in Rheumatoid Arthritis: A Systematic Review

Tumor necrosis factor-alpha (TNF-α) plays an important role in coronary heart disease (CHD), a chronic inflammatory process. Meanwhile, this pro-inflammatory factor is also involved in the pathogenesis of autoimmune diseases such as rheumatoid arthritis (RA). Patients with RA correspond to a higher risk of CHD. TNF-α antagonist, one of the main treatments for RA, may reduce the risk of CHD in patients with RA. This review summarizes the pathogenesis of TNF-α in CHD and discusses the relationship between TNF-α antagonist and CHD in patients with RA.

The Microenvironment That Regulates Vascular Wall Stem/Progenitor Cells in Vascular Injury and Repair

Vascular repair upon injury is a frequently encountered pathology in cardiovascular diseases, which is crucial for the maintenance of arterial homeostasis and function. Stem/progenitor cells located on vascular walls have multidirectional differentiation potential and regenerative ability. It has been demonstrated that stem/progenitor cells play an essential role in the basic medical research and disease treatment. The dynamic microenvironment around the vascular wall stem/progenitor cells (VW-S/PCs) possesses many stem cell niche-like characteristics to support and regulate cells' activities, maintaining the properties of stem cells. Under physiological conditions, vascular homeostasis is a cautiously balanced and efficient interaction between stem cells and the microenvironment. These interactions contribute to the vascular repair and remodeling upon vessel injury. However, the signaling mechanisms involved in the regulation of microenvironment on stem cells remain to be further elucidated. Understanding the functional characteristics and potential mechanisms of VW-S/PCs is of great significance for both basic and translational research. This review underscores the microenvironment-derived signals that regulate VW-S/PCs and aims at providing new targets for the treatment of related cardiovascular diseases.

The anti-angiogenesis mechanism of Geniposide on rheumatoid arthritis is related to the regulation of PTEN

Rheumatoid arthritis (RA) is a systemic immune disease characterized by joint inflammation and pannus. The nascent pannus contributes to synovial hyperplasia, cartilage, and tissue damage in RA. This study aims to explore the therapeutic effect and potential mechanism of Geniposide (GE) on RA angiogenesis, involving the participation of phosphate and tension homology deleted on chromosome ten (PTEN) and downstream pathways. Clinical manifestations, synovial pathomorphology, microvessel density, and the level of angiogenesis-related factors were used to evaluate the therapeutic effect of GE on adjuvant-induced arthritis (AA) rats. The proliferation, migration, and tube formation of human umbilical vein endothelial cells (HUVECs) indicate the degree of angiogenesis in vitro. Lentivirus over-expression of PTEN was employed to elucidate the potential mechanism. The results showed that GE improved the degree of arthritis and angiogenesis in AA rats. The expression of PTEN was decreased significantly in vivo and in vitro, and over-expression of PTEN improved the biological function of HUVECs to inhibit angiogenesis. GE inhibited the proliferation, migration, and tubule formation of HUVECs and plays an anti-angiogenesis role in vitro. Mechanism study showed that PTEN expression was increased and p-PI3K and p-Akt expression was decreased with GE treatment. It suggests that GE up-regulated the expression of PTEN and inhibited the activation of PI3K-Akt signal, which plays a role in inhibiting angiogenesis in RA in vivo and in vitro.

Endothelial Progenitor Cells and Rheumatoid Arthritis: Response to Endothelial Dysfunction and Clinical Evidences

Rheumatoid Arthritis (RA) is a chronic autoimmune inflammatory disease characterized by the swelling of multiple joints, pain and stiffness, and accelerated atherosclerosis. Sustained immune response and chronic inflammation, which characterize RA, may induce endothelial activation, damage and dysfunction. An equilibrium between endothelial damage and repair, together with the preservation of endothelial integrity, is of crucial importance for the homeostasis of endothelium. Endothelial Progenitor Cells (EPCs) represent a heterogenous cell population, characterized by the ability to differentiate into mature endothelial cells (ECs), which contribute to vascular homeostasis, neovascularization and endothelial repair. A modification of the number and function of EPCs has been described in numerous chronic inflammatory and auto-immune conditions; however, reports that focus on the number and functions of EPCs in RA are characterized by conflicting results, and discrepancies exist among different studies. In the present review, the authors describe EPCs' role and response to RA-related endothelial modification, with the aim of illustrating current evidence regarding the level of EPCs and their function in this disease, to summarize EPCs' role as a biomarker in cardiovascular comorbidities related to RA, and finally, to discuss the modulation of EPCs secondary to RA therapy.

Asymmetric Dimethylarginine: a Key Player in the Pathophysiology of Endothelial Dysfunction, Vascular Inflammation and Atherosclerosis in Rheumatoid Arthritis?

Patients with rheumatoid arthritis (RA), a chronic and disabling autoimmune condition that is characterized by articular and extra-articular manifestations and a pro-inflammatory and pro-oxidant state, suffer from premature atherosclerosis and excessive cardiovascular disease burden. A key step in the pathogenesis of atherosclerosis is impaired synthesis of the endogenous messenger nitric oxide (NO) by endothelial cells which, in turn, alters local homeostatic mechanisms and favors vascular damage and plaque deposition. While the exact mechanisms of endothelial dysfunction in RA remain to be established, there is good evidence that RA patients have relatively high circulating concentrations of the methylated arginine asymmetric dimethylarginine (ADMA), a potent endogenous inhibitor of endothelial NO synthase (eNOS). This review discusses the biological and pathophysiological role of ADMA, the interplay between ADMA, inflammation and oxidative stress, and the available evidence on the adverse impact of ADMA on endothelial function and atherosclerosis and potential ADMA-lowering therapies in RA patients.

Tumour necrosis factor inhibitors reduce aortic stiffness progression in patients with long-standing rheumatoid arthritis

BACKGROUND

Aortic stiffness index (AoSI) has to be considered a proxy outcome measure in patients with rheumatoid arthritis (RA). The aim of this study was to comparatively describe AoSI progression in two groups of RA patients on long-term treatment with conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs) with or without tumour necrosis factor inhibitors (TNFi).

METHODS

AoSI was evaluated by Doppler echocardiography at the level of the aortic root, using a two-dimensional guided M-mode evaluation. Eligible participants were assessed at baseline and after 12 months. Changes in serum lipids, glucose and arterial blood pressure were assessed. All patients who did not change DMARD treatment during follow-up were consecutively selected for this study.

RESULTS

We included 107 (64 TNFi and 43 csDMARDs) RA patients. Most patients (74%) were in remission or low disease activity and had some CVD risk factors (45.8% hypertension, 59.8% dyslipidaemia, 45.3% smoking). The two groups did not differ significantly for baseline AoSI (5.95±3.73% vs 6.08±4.20%, p=0.867). Follow-up AoSI was significantly increased from baseline in the csDMARDs group (+1.00%; p<0.0001) but not in the TNFi group (+0.15%, p=0.477). Patients on TNFi had significantly lower follow-up AoSI from baseline than the csDMARDs group (-1.02%, p<0.001; ANCOVA corrected for baseline AoSI, age and systolic blood pressure). Furthermore, follow-up AoSI was significantly lower in TNFi than in csDMARDs users with an increasing number of CVD risk factors.

CONCLUSION

Long-term treatment with TNFi was associated with reduced aortic stiffness progression in patients with established RA and several CVD risk factors.

Biologics and atherosclerotic cardiovascular risk in rheumatoid arthritis: a review of evidence and mechanistic insights

Introduction: Cardiovascular disease is a leading comorbidity in rheumatoid arthritis. Timely introduction of biologic therapies in a treat-to-target approach has optimized disease-related outcomes and attenuated accrual of comorbidities, including cardiovascular risk.Areas covered: A literature search in MEDLINE (via PubMed) was performed between January 2009 and November 2020. This manuscript explores recent developments in atherosclerotic cardiovascular risk in RA compared with non-RA individuals; it synopsizes differences in vascular function and inflammation, prevalence, burden, vulnerability, and progression of atherosclerotic plaque and their underlying cellular and molecular mechanisms. Finally, it reviews the recent literature on cardioprotective benefits of biologics and draws mechanistic links with inhibition of new plaque formation, stabilization of high-risk lesions and improvement in endothelial function, arterial stiffness, lipid metabolism, and traditional cardiac risk factors.Expert opinion: Increasing evidence points to a solid cardioprotective influence of earlier, longer, and ongoing use of biologic treatments in RA. Nevertheless, the precise mechanistic effects of plaque progression and remodeling, vascular stiffness, endothelial dysfunction, lipid metabolism, and traditional cardiac risk factors are less rigorously characterized.

Increased number of endothelial progenitor cells in the blood of patients with psoriasis vulgaris

Introduction

Psoriasis vulgaris (PsV) is a common dermatosis characterized by excessive activation of neovascularization. Latest research has shown that endothelial progenitor cells (EPCs) are a crucial factor involved in the repair of endothelial injury and formation of new blood vessels, in a process termed postnatal vasculogenesis. However, the exact mechanism of creating psoriatic skin patches and the involvement of EPCs in this process remains unknown.

Aim

To evaluate the number of EPCs in the blood of patients with PsV, characterized by the expression of specific cell surface markers, including CD45-, CD31+, CD34+ and CD133+.

Material and methods

A total of 49 patients suffering from PsV and 40 healthy volunteers were enrolled in the study. The number of EPCs in each of the volunteers' whole blood samples was measured with a FACSCalibur flow cytometer using monoclonal antibodies directed against antigens specific for EPCs.

Results

The number of EPCs was significantly higher in patients with psoriasis compared with the controls (p = 0.0007) and inversely correlated with disease severity assessed by PASI score (R = -0.2935, p = 0.0407). Statistical analysis did not show significant relations between the count of EPCs and age, body mass index, gender, disease duration, blood pressure, extent of itching, severity and frequency of pruritus, presence of bruises, vitamin D supplementation and smoking habit.

Conclusions

The results of our studies indicate that patients with psoriasis showed an increased mobilization of EPCs compared with healthy individuals which correlated negatively with disease severity.

Role of the eNOS Uncoupling and the Nitric Oxide Metabolic Pathway in the Pathogenesis of Autoimmune Rheumatic Diseases

Atherosclerosis and its clinical complications constitute the major healthcare problems of the world population. Due to the central role of endothelium throughout the atherosclerotic disease process, endothelial dysfunction is regarded as a common mechanism for various cardiovascular (CV) disorders. It is well established that patients with rheumatic autoimmune diseases are characterized by significantly increased prevalence of cardiovascular morbidity and mortality compared with the general population. The current European guidelines on cardiovascular disease (CVD) prevention in clinical practice recommend to use a 1,5-factor multiplier for CV risk in rheumatoid arthritis as well as in other autoimmune inflammatory diseases. However, mechanisms of accelerated atherosclerosis in these diseases, especially in the absence of traditional risk factors, still remain unclear. Oxidative stress plays the major role in the endothelial dysfunction and recently is strongly attributed to endothelial NO synthase dysfunction (eNOS uncoupling). Converted to a superoxide-producing enzyme, uncoupled eNOS not only leads to reduction of the nitric oxide (NO) generation but also potentiates the preexisting oxidative stress, which contributes significantly to atherogenesis. However, to date, there are no systemic analyses on the role of eNOS uncoupling in the excess CV mortality linked with autoimmune rheumatic diseases. The current review paper addresses this issue.

B lymphocyte stimulator modulates number and function of endothelial progenitor cells in systemic lupus erythematosus

Background

Circulating endothelial progenitor cells (EPCs) are biologic markers of endothelial function. In patients with systemic lupus erythematosus (SLE), the numerical reduction and functional impairment of EPCs contribute to the endothelial dysfunction.

Through ex vivo and in vitro studies, we aimed at evaluating the effects of B lymphocyte stimulator (BLyS) on EPC colonies and endothelial cells and also investigating BLyS receptor expression on these cells.

Methods

EPCs were isolated from peripheral blood mononuclear cells (PBMC). In order to evaluate their ability to form colonies, EPCs were cultured on fibronectin-coated dishes and incubated with BlyS alone or BlyS and belimumab. Apoptosis of EPCs and endothelial cell line EA.hy926 was evaluated after 6, 12, and 24 h of incubation with BLyS and after 6 h with BLyS and belimumab. The expression of B cell activating factor-receptor (BAFF-R), B cell maturation antigen (BCMA), and transmembrane activator and calcium modulator and cyclophilin ligand (CAML) interactor (TACI) on EPCs and EA.hy926 was analyzed by cytofluorimetry.

Results

The number of EPC colonies was lower in patients than in controls. Moreover, the colonies from SLE patients were poorly organized compared to controls; the addition of belimumab restored the colony structure. Incubation with BLyS induced apoptosis of EPCs and EA.hy926 that was inhibited by the co-incubation with belimumab. BAFF-R and BCMA were expressed on both EPCs and EA.hy926, while TACI was expressed only on EPCs.

Conclusions

EPCs and endothelial cells preferentially express BAFF-R which could be involved in the pro-apoptotic effect of BlyS. Belimumab administration seems to restore the quantitative and qualitative changes of EPC colonies both ex vivo and in vitro.

Piper sarmentosum Promotes Endothelial Nitric Oxide Production by Reducing Asymmetric Dimethylarginine in Tumor Necrosis Factor-α-Induced Human Umbilical Vein Endothelial Cells

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of endothelial nitric oxide synthase (eNOS). ADMA is degraded by dimethylarginine dimethylaminohydrolase (DDAH). Elevated levels of ADMA lead to reduction in nitric oxide (NO) production, which is linked to endothelial dysfunction and atherosclerosis. Piper sarmentosum is an herb that has shown stimulation on endothelial NO production by increasing both expression and activity of eNOS. Thus, this study determined whether the positive effect of P. sarmentosum on NO production is related to its modulation on the DDAH-ADMA pathway in cultured human umbilical vein endothelial cells (HUVEC) exposed to tumor necrosis factor-α (TNF-α). HUVEC were divided into four groups: control, treatment with 250 µg/ml of aqueous extract of P. sarmentosum leaves (AEPS), treatment with 30 ng/ml of TNF-α, and concomitant treatment with AEPS and TNF-α for 24 h. After treatments, HUVEC were collected to measure DDAH1 messenger RNA (mRNA) expression using quantitative real-time polymerase chain reaction. DDAH1 protein level was measured using enzyme-linked immunosorbent assay (ELISA), and DDAH enzyme activity was measured using colorimetric assay. ADMA concentration was measured using ELISA, and NO level was measured using Griess assay. Compared to control, TNF-α-treated HUVEC showed reduction in DDAH1 mRNA expression (P < 0.05), DDAH1 protein level (P < 0.01), and DDAH activity (P < 0.05). Treatment with AEPS successfully increased DDAH1 mRNA expression (P < 0.05), DDAH1 protein level (P < 0.01), and DDAH activity (P < 0.05) in TNF-α-treated HUVEC. Treatment with TNF-α caused an increase in ADMA level (P < 0.01) and a decrease in endothelial NO production (P < 0.001). Whereas treatment with AEPS was able to reduce ADMA level (P < 0.01) and restore NO (P < 0.001) in TNF-α-treated HUVEC. The results suggested that AEPS promotes endothelial NO production by stimulating DDAH activity and thus reducing ADMA level in TNF-α-treated HUVEC.

Reverse-D-4F improves endothelial progenitor cell function and attenuates LPS-induced acute lung injury

Background

Patients with acute lung injury (ALI) have increased levels of pro-inflammatory mediators, which impair endothelial progenitor cell (EPC) function. Increasing the number of EPC and alleviating EPC dysfunction induced by pro-inflammatory mediators play important roles in suppressing ALI development. Because the high density lipoprotein reverse-D-4F (Rev-D4F) improves EPC function, we hypothesized that it might repair lipopolysaccharide (LPS)-induced lung damage by improving EPC numbers and function in an LPS-induced ALI mouse model.

Methods

LPS was used to induce ALI in mice, and then the mice received intraperitoneal injections of Rev-D4F. Immunohistochemical staining, flow cytometry, MTT, transwell, and western blotting were used to assess the effect of Rev-D4F on repairment of lung impairment, and improvement of EPC numbers and function, as well as the signaling pathways involved.

Results

Rev-D4F inhibits LPS-induced pulmonary edema and decreases plasma levels of the pro-inflammatory mediators TNF-α and ET-1 in ALI mice. Rev-D4F inhibited infiltration of red and white blood cells into the interstitial space, reduced lung injury-induced inflammation, and restored injured pulmonary capillary endothelial cells. In addition, Rev-D4F increased numbers of circulating EPC, stimulated EPC differentiation, and improved EPC function impaired by LPS. Rev-D4F also acted via a PI3-kinase-dependent mechanism to restore levels of phospho-AKT, eNOS, and phospho-eNOS suppressed by LPS.

Conclusions

These findings indicate that Rev-D4F has an important vasculoprotective role in ALI by improving the EPC numbers and functions, and Rev-D4F reverses LPS-induced EPC dysfuncion partially through PI3K/AKT/eNOS signaling pathway.

Electronic supplementary material

The online version of this article (10.1186/s12931-019-1099-6) contains supplementary material, which is available to authorized users.

Meta-Analysis of Asymmetric Dimethylarginine Concentrations in Rheumatic Diseases

Raised circulating concentrations of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase (NOS), have been reported in several rheumatic diseases (RDs). However, the strength of this relationship is unclear. Therefore, the aim of this systematic review and meta-analysis was to evaluate the magnitude and the robustness of the association between ADMA concentrations and RDs. We calculated standardized mean differences (SMD, with 95% confidence intervals, CI). Study heterogeneity was evaluated by meta-regressions and sensitivity analyses according to type of RDs, conventional cardiovascular risk factors, inflammatory markers, and type of ADMA assessment methodology. Thirty-seven studies with a total of 2,982 subjects (1,860 RDs patients and 1,122 healthy controls) were included in our meta-analysis. Pooled results showed that ADMA concentrations were significantly higher in patients with RDs than in healthy controls (SMD = 1.27 µmol/L, 95% CI 0.94–1.60 µmol/L; p < 0.001). However, the between-studies heterogeneity was high. Differences in ADMA concentrations between controls and RDs patients were not significantly associated with inflammatory markers, increasing age, lipid concentrations, body mass index, blood pressure, or methodology used to assess ADMA. Furthermore, subgroup analysis showed no difference across RDs. This meta-analysis showed that, in the context of significant between-study heterogeneity, circulating concentrations of ADMA are positively related to RDs.

Early endothelial progenitor cells and vascular stiffness in psoriasis and psoriatic arthritis

BACKGROUND

Both psoriasis (Ps) and psoriasis arthritis (PsA) have been associated with increased cardiovascular risk. Also, both are characterized by increased neovascularization. Endothelial progenitor cells (EPCs) have been implicated in promoting vascular repair in ischemic diseases. The aim of the study was to correlate the EPC system with CV risk factors and with parameters of vascular stiffness in Ps and PsA.

METHODS

Twenty-six healthy subjects, 30 patients with Ps, and 31 patients PsA were included in the study. eEPC regeneration was evaluated by a colony-forming assay, circulating eEPCs were measured by cytometric analysis. For vascular analysis, all subjects underwent quantification of pulse wave velocity (PWV) and augmentation index (AIX).

RESULTS

Patients were categorized upon the duration of disease, severity of skin involvement (PASI-Ps), individual pain as reflected by the VAS (PsA), CRP values, and history of treatment with one or more biologicals. Regarding the eEPC system, no significant differences were observed between the respective categories. Correlation analyses between parameters of vascular stiffness (PWV and AIX) and patterns of colony formation/circulating eEPCs did not show any correlation at all.

CONCLUSION

Parameters of vascular stiffness are not significantly deteriorated in Ps/PsA. Thus, pulse wave analysis may not be suitable for CVR assessment in certain autoimmune-mediated diseases. Regenerative activity of the eEPC system/circulating eEPC numbers are not altered in Ps/PsA. One may conclude that malfunctions of the eEPC are not substantially involved in perpetuating the micro-/macrovascular alterations in Ps/PsA.

Endothelial progenitor cells and rheumatic disease modifying therapy

Rheumatic diseases are associated with accelerated atherosclerosis and with increased risk of cardiovascular morbidity and mortality. The mechanisms underlying the higher prevalence of cardiovascular disease are not completely clarified, but it is likely that a pivotal role is played by vascular inflammation and consequently to altered vascular endothelium homeostasis. Also, high prevalence of traditional risk factors, proatherogenic activation and endothelial dysfunction further contribute to vascular damage. Circulating endothelial progenitor cells (EPCs) can restore dysfunctional endothelium and protect against atherosclerotic vascular disease. However, abnormalities in number and function of these cells in patients with rheumatic condition have been extensively reported. During the last years, growing interest in the mechanisms of endothelial renewal and its potential as a therapy for CVD has been shown; in addition, pioneering studies show that EPC dysfunction might be improved with pharmacological strategies. However, how to restore EPC function, and whether achieving this aim may be effective in preventing cardiovascular complications in rheumatic disease, remain to be established. In this review we report an overview on the current stand of knowledge on the effect of pharmaceutical and lifestyle intervention in improving EPCs number and function in rheumatic disease.

Endothelial Progenitor Cells: New Targets for Therapeutics for Inflammatory Conditions With High Cardiovascular Risk

Over the past decade, we have witnessed an exponential growth of interest into the role of endothelial progenitor cells (EPCs) in cardiovascular disease. While the major thinking revolves around EPC angiogenic repair properties, we have used a hypothesis-driven approach to discover disease-related defects in their characteristics and based on these findings, have identified opportunities for functional enhancement, which offer an exciting avenue for translation into clinical intervention. In this review, we focus on two groups; circulating myeloid angiogenic cells (MACs) and late outgrowth endothelial colony forming cells (ECFCs), and will discuss the unique properties and defects of each population, as new insights have been gained into the potential function of each sub-type using current techniques and multiomic technology. We will discuss their role in inflammatory disorders and alterations in mitochondrial function. In addition, we share key insights into the glycocalyx, and propose this network of membrane-bound proteoglycans and glycoproteins, covering the endothelium warrants further investigation in order to clarify its significance in ECFC regulation of vascularization and angiogenesis and ultimately for potential translational therapeutic aspects.

Cardiovascular outcomes of patients with rheumatoid arthritis prescribed disease modifying anti-rheumatic drugs: a review

INTRODUCTION

Rheumatoid arthritis (RA) is associated with a heightened risk of cardiovascular disease (CVD), with both traditional CV risk factors and inflammation contributing to this risk.

AREAS COVERED

This review highlights the burden of CVD in RA and associated traditional CV risk factors, including the complexity of dyslipidemia in RA and the so-called 'lipid paradox.' Furthermore, the recognized RA-disease-specific factors associated with higher risk of CVD and the role of systemic inflammation in the pathogenesis of CVD in RA will be addressed. With the advent of biologic and targeted synthetic therapies in the treatment of RA, the effect of conventional and newer generation disease modifying anti-rheumatic therapies (DMARDs) on CV risk and associated risk factors will also be discussed.

EXPERT OPINION

Identifying the RA phenotype at greatest risk of CVD, understanding the interplay of increased traditional risk factors, common inflammatory processes and RA-specific factors, and personalized use of DMARDs according to disease phenotype and comorbidity to reduce this risk are key areas for future research.

Increased cardiovascular risk in rheumatoid arthritis: mechanisms and implications

Rheumatoid arthritis is a systemic autoimmune disease characterized by excess morbidity and mortality from cardiovascular disease. Mechanisms linking rheumatoid arthritis and cardiovascular disease include shared inflammatory mediators, post-translational modifications of peptides/proteins and subsequent immune responses, alterations in the composition and function of lipoproteins, increased oxidative stress, and endothelial dysfunction. Despite a growing understanding of these mechanisms and their complex interplay with conventional cardiovascular risk factors, optimal approaches of risk stratification, prevention, and treatment in the context of rheumatoid arthritis remain unknown. A multifaceted approach to reduce the burden posed by cardiovascular disease requires optimal management of traditional risk factors in addition to those intrinsic to rheumatoid arthritis such as increased disease activity. Treatments for rheumatoid arthritis seem to exert differential effects on cardiovascular risk as well as the mechanisms linking these conditions. More research is needed to establish whether preferential rheumatoid arthritis therapies exist in terms of prevention of cardiovascular disease. Ultimately, understanding the unique mechanisms for cardiovascular disease in rheumatoid arthritis will aid in risk stratification and the identification of novel targets for meaningful reduction of cardiovascular risk in this patient population.

Asymmetric Dimethyl Arginine as a Biomarker of Atherosclerosis in Rheumatoid Arthritis

Cardiovascular disease is the main cause of morbidity and mortality in rheumatoid arthritis (RA). Despite the advent on new drugs targeting the articular manifestations, the burden of cardiovascular disease is still an unmet need in the management of RA. The pathophysiology of accelerated atherosclerosis associated to RA is not yet fully understood, and reliable and specific markers of early cardiovascular involvement are still lacking. Asymmetric dimethylarginine is gaining attention for its implication in the pathogenesis of endothelial dysfunction and as biomarkers of subclinical atherosclerosis. Moreover, the metabolic pathway of methylarginines offers possible targets for therapeutic interventions to decrease the cardiovascular risk. The purpose of this review is to describe the main causes of increased methylarginine levels in RA, their implication in accelerated atherosclerosis, the possible role as biomarkers of cardiovascular risk, and finally the available data on current pharmacological treatment.

Protective Effects of Methotrexate against Proatherosclerotic Cytokines: A Review of the Evidence

There is good epidemiological evidence that patients with autoimmune rheumatic disease states, particularly rheumatoid arthritis, have an increased risk of cardiovascular morbidity and mortality when compared to the general population. The presence of a chronic systemic proinflammatory state in this patient group disrupts the structural and functional integrity of the endothelium and the arterial wall, favouring the onset and progression of atherosclerosis. A significant role in the detrimental effects of inflammation on endothelial function and vascular homeostasis is played by specific proatherosclerotic cytokines such as tumour necrosis factor-alpha (TNF-α), interleukin-1 (IL-1), and interleukin-6 (IL-6). Recent systematic reviews and meta-analyses have shown that treatment with methotrexate, a first-line disease-modifying antirheumatic drug (DMARD), is associated with a significant reduction in atherosclerosis-mediated cardiovascular events, such as myocardial infarction and stroke, and mortality, when compared to other DMARDs. This suggests that methotrexate might exert specific protective effects against vascular inflammation and atherosclerosis in the context of autoimmune rheumatic disease. This review discusses the available evidence regarding the potential antiatherosclerotic effects of methotrexate through the inhibition of TNF-α, IL-1, and IL-6 and provides suggestions for future experimental and human studies addressing this issue.

Anti-TNF-alpha agents and endothelial function in rheumatoid arthritis: a systematic review and meta-analysis

Rheumatoid arthritis (RA) has been associated with endothelial dysfunction, a pathophysiological feature of atherosclerosis. Our aim was to determine whether TNF-α blockade has a beneficial effect on endothelial function in RA. We performed a systematic review with meta-analysis to evaluate the effect of anti-TNF-α agents on endothelial function in RA patients. MedLine, Cochrane CENTRAL and SCOPUS were searched up to March 2016. Inclusion criteria were: 1) randomised controlled trial (RCT), quasi-RCT, before-after cohort study; 2) including RA patients; 3) treatment with anti-TNF-α medications; 4) evaluating the change from baseline in endothelial function. The search strategy retrieved 180 records, of which 20 studies were included in the systematic review. Pooled analysis using a random-effects model demonstrated a significant improvement in endothelial function following anti-TNF-α treatment (SDM 0.987, 95%CI [0.64–1.33], p < 0.0001). Generalisation of the results of the meta-analysis may be limited due to the presence of heterogeneity (I2 = 82.65%, p < 0.001) and evidence of possible publication bias. Meta-regression showed that endothelial function measurement technique was a significant contributor to heterogeneity. In conclusion, although limited by the methodological quality of the included studies, our meta-analysis suggests that anti-TNF-α treatment may improve endothelial function in RA patients.

Association between antibodies to carbamylated proteins and subclinical atherosclerosis in rheumatoid arthritis patients

BACKGROUND

Rheumatoid arthritis (RA) patients carry a high risk of cardiovascular morbidity and mortality. The excess of cardiovascular disease cannot be entirely explained by traditional risk factors and the immune system contributes to the development of atherosclerosis. Moreover, post-translational modifications such as citrullination and carbamylation have been linked to inflammation and atherosclerosis. Anti-carbamylated proteins antibodies (anti-CarP) are a new subset of autoantibodies identified in RA patients. This study aimed to investigate a possible association between anti-CarP and subclinical atherosclerosis in RA patients.

METHODS

We enrolled RA patients and normal healthy controls (NHS) without known cardiovascular risk factors or heart disease. Cardiovascular risk was assessed using the Modified Systemic Coronary Risk Evaluation (mSCORE). Anti-CarP were investigated by a solid phase "home-made" ELISA. Anti-citrullinated protein antibodies (ACPA) and Rheumatoid Factor (RF) were investigated by ELISA assays. Subclinical atherosclerosis was evaluated by brachial artery Flow-Mediated Dilatation (FMD) and Carotid Intima-Media Thickness (c-IMT) while arterial stiffness by Ankle-Brachial Index (ABI) and Cardio-Ankle Vascular Index (CAVI).

RESULTS

We enrolled 50 RA patients (34 F and 16 M, mean age 58.4 ± 13.1 years, mean disease duration 127 ± 96.7 months) and 30 age and sex matched NHS. According to the mSCORE, 58% of patients had a low risk, 32% a moderate and 8% a high risk for cardiovascular disease. FMD was significantly lower in RA patients than in NHS (5.6 ± 3.2 vs 10.7 ± 8.1%; p < 0.004) and CAVIs significantly higher in a RA patients compared to NHS (left CAVI 8.9 ± 1.7 vs 8.1 ± 1.5; p < 0.04 for and right CAVI 8.8 ± 1.6 vs 8.0 ± 1.4; p < 0.04 for the). ABI and c-IMT did not differ between the two populations. The multivariate regression analysis showed a significant association of anti-CarP antibodies with FMD, left and right CAVI and both c-IMT (r = 1.6 and p = 0.05; r = 1.7 and p = 0.04; r = 2.9 and p = 0.05; r = 1.5 and p = 0.03; r = 1.1 and p = 0.03 respectively).

CONCLUSIONS

This study confirms that RA patients, without evidence of cardiovascular disease or traditional risk factors, have an impaired endothelial function. Moreover, we found an association with anti-CarP antibodies suggesting a possible contribution of these autoantibodies to endothelial dysfunction, the earliest stage of atherosclerosis. Besides ultrasound assessment, anti-CarP should be assessed in RA patients and considered an additional cardiovascular risk factor.

A New Explanation of Inflammation in Rheumatoid Arthritis Patients With Respect to Claudin-5, Matrix Metalloproteinase-9, and Neuroserpin

Objectives

This study aims to investigate the relationship between neuroserpin (NSP) and claudin-5, as well as matrix metalloproteinase-9 (MMP-9), with respect to clinical activity of disease in patients with rheumatoid arthritis.

Patients and methods

The study included a total of 75 patients (18 males, 57 females; mean age 48.12±11.23 years; range 20 to 60 years) who were admitted to the rheumatology outpatient facility at the Medical Faculty Hospital, Sakarya University, in October 2014. Patients were divided into four groups based on their Disease Activity Score 28 (DAS28) scores as remission group (n=16, DAS28 <2.6), low disease activity group (n=16, DAS28 between 2.6-3.2), moderate disease activity group (n=28, DAS28 between 3.2-5.1), and high disease activity group (n=15, DAS28 >5.1). Ten healthy subjects (HS) served as controls.

Results

Claudin-5, MMP-9, and NSP levels were significantly different in rheumatoid arthritis patients compared to HS (p=0.035, 0.026, and 0.014, respectively). Additionally, there were no differences between claudin-5 levels and disease activity among all RA groups. However, compared to HS, patient groups showed a significant difference (p=0.035) in terms of claudin-5 levels. Serum levels of MMP-9 were significantly different in moderate disease activity group compared to HS (p=0.013). Levels of NSP were significantly different in moderate disease activity and high disease activity groups compared to HS (p=0.008 and 0.031, respectively).

Conclusion

Our study demonstrated the differential associations of endothelial function/dysfunction biomarkers and disease activity in rheumatoid arthritis. How and why this impairment occurs is not fully understood and more data regarding NSP, MMP, and claudin expression in plasma are warranted.

Etanercept improves endothelial function via pleiotropic effects in rat adjuvant-induced arthritis

OBJECTIVES

To determine the effect of etanercept on endothelial dysfunction and on traditional cardiovascular (CV) risk factors in the adjuvant-induced arthritis (AIA) rat model.

METHODS

At the first signs of arthritis, etanercept (10 mg/kg/3 days, s.c.) or saline was administered for 3 weeks in AIA rats. Body weights and arthritis scores were monitored daily. Endothelial function was studied in aortic rings relaxed with acetylcholine (Ach) with or without inhibitors of nitric oxide synthase (NOS), cyclo-oxygenase (COX-2), arginase, endothelium-derived hyperpolarizing factor and superoxide anions (O2 (-)°) production. Aortic expression of endothelial nitic oxide synthase (eNOS), Ser1177-phospho-eNOS, COX-2, arginase-2, p22(phox) and p47(phox) was evaluated by western blotting analysis. Blood pressure, heart rate and blood levels of triglycerides, cholesterol and glucose were measured.

RESULTS

Etanercept significantly reduced arthritis score (P < 0.001). It improved Ach-induced relaxation (P < 0.05) as a result of increased NOS activity, decreased COX-2/arginase activities and decreased O2 (-)° production. These functional effects relied on increased eNOS expression and phosphorylation, and decreased COX-2, arginase-2 and p22(phox) expressions. No correlation was found between arthritis score and Ach-induced relaxation. The treatment did not change triglycerides, cholesterol and glucose levels, but significantly increased systolic blood pressure and heart rate (P < 0.05).

CONCLUSION

Our data demonstrated that efficient dosage of etanercept on inflammatory symptoms improved endothelial function in AIA. This beneficial effect on endothelial function is disconnected from its impact on CV risk factors and relates to pleiotropic effects of etanercept on endothelial pathways. These results suggest that etanercept could be a good choice for patients with rheumatoid arthritis at high risk of CV events.

Endothelial Dysfunction and Inflammation: Immunity in Rheumatoid Arthritis

Inflammation, as a feature of rheumatoid arthritis (RA), leads to the activation of endothelial cells (ECs). Activated ECs induce atherosclerosis through an increased expression of leukocyte adhesion molecules. Endothelial dysfunction (ED) is recognized as a failure of endothelial repair mechanisms. It is also an early preclinical marker of atherosclerosis and is commonly found in RA patients. RA is now established as an independent cardiovascular risk factor, while mechanistic determinants of ED in RA are still poorly understood. An expanding body of study has shown that EC at a site of RA is both active participant and regulator of inflammatory process. Over the last decade, a role for endothelial dysfunction in RA associated with cardiovascular disease (CVD) has been hypothesized. At the same time, several maintenance drugs targeting this phenomenon have been tested, which has promising results. Assessment of endothelial function may be a useful tool to identify and monitor RA patients.

Inflammatory cytokines in atherosclerosis: current therapeutic approaches

The notion of atherosclerosis as a chronic inflammatory disease has intensified research on the role of cytokines and the way these molecules act and interact to initiate and sustain inflammation in the microenvironment of an atherosclerotic plaque. Cytokines are expressed by all types of cells involved in the pathogenesis of atherosclerosis, act on a variety of targets exerting multiple effects, and are largely responsible for the crosstalk among endothelial, smooth muscle cells, leucocytes, and other vascular residing cells. It is now understood that widely used drugs such as statins, aspirin, methotrexate, and colchicine act in an immunomodulatory way that may beneficially affect atherogenesis and/or cardiovascular disease progression. Moreover, advancement in pharmaceutical design has enabled the production of highly specific antibodies against key molecules involved in the perpetuation of the inflammatory cascade, raising hope for advances in the treatment of atherosclerosis. This review describes the actions and effects of these agents, their potential clinical significance, and future prospects.

Targeting inflammation in the prevention of cardiovascular disease in patients with inflammatory arthritis

Patients with inflammatory arthritis have increased risk of cardiovascular diseases (CVDs) compared with the general population. Subclinical carotid atherosclerosis and increased arterial stiffness are also common in these patients, which may serve as surrogate end points for cardiovascular (CV) events in clinical trials. Although exact mechanisms are still unclear, persistent systemic inflammation in patients with inflammatory arthritis may contribute to the development of CVD. Dysregulated innate immunity pathways in these patients may also play a role in accelerating atherosclerosis. During the last decade, effective suppression of inflammation by biological disease-modifying antirheumatic drugs has improved the disease outcome dramatically in patients with inflammatory arthritis. Growing evidence suggests that antitumor necrosis factor (TNF) therapy may prevent CVD in patients with rheumatoid arthritis. Nonetheless, data on non-TNF biologics are limited. Whether anti-TNF therapy may prevent CVD in patients with spondyloarthritis also remained unclear. In this review, we summarized the effect of both anti-TNF and non-TNF biologics on the CV system, including traditional CVD risk factors, endothelial function, arterial stiffness, subclinical atherosclerosis, and clinical CVD in patients with inflammatory arthritis.

Clinical assessment of endothelial function in patients with rheumatoid arthritis: A meta-analysis of literature studies

BACKGROUND

Several studies reported an increased cardiovascular (CV) morbidity and mortality in patients with rheumatoid arthritis (RA). Flow-mediated (FMD) and nitrate-mediated dilation (NMD) are considered non-invasive methods to assess endothelial function and surrogate markers of subclinical atherosclerosis.

METHODS

We performed a systematic review with meta-analysis and meta-regression of literature studies evaluating the impact of RA on FMD and NMD. Studies evaluating the relationship between RA and markers of CV risk (FMD and NMD) were systematically searched in the PubMed, Web of Science, Scopus and EMBASE databases. The random-effect method was used for analyses and results were expressed as mean difference (MD).

RESULTS

A total of 20 studies (852 RA patients, 836 controls) were included in the final analysis. In detail, 20 studies with data on FMD (852 cases, 836 controls) and 5 studies with data on NMD (207 cases, 147 controls) were analyzed. Compared to controls, RA patients showed a significantly lower FMD (MD: -2.16%; 95% CI: -3.33, -0.98; P=0.0003), with no differences in NMD (MD: -0.41%; 95% CI: -2.89, 2.06; P=0.74). Interestingly, a lower FMD (MD: -2.00%; 95% CI: -3.20, -0.80; P=0.001) and no differences in NMD (P=0.49) were confirmed when excluding data on patients with early-RA. Meta-regression models showed that a more severe inflammatory status was associated with a more significant impairment in FMD.

CONCLUSIONS

RA patients show impaired FMD, which is currently considered an independent predictor of CV events. The presence of endothelial dysfunction in RA should be taken into account to plan adequate prevention strategies and therapeutic approaches.

The interplay between inflammation and metabolism in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by extensive synovitis resulting in erosions of articular cartilage and marginal bone that lead to joint destruction. The autoimmune process in RA depends on the activation of immune cells, which use intracellular kinases to respond to external stimuli such as cytokines, immune complexes, and antigens. An intricate cytokine network participates in inflammation and in perpetuation of disease by positive feedback loops promoting systemic disorder. The widespread systemic effects mediated by pro-inflammatory cytokines in RA impact on metabolism and in particular in lymphocyte metabolism. Moreover, RA pathobiology seems to share some common pathways with atherosclerosis, including endothelial dysfunction that is related to underlying chronic inflammation. The extent of the metabolic changes and the types of metabolites seen may be good markers of cytokine-mediated inflammatory processes in RA. Altered metabolic fingerprints may be useful in predicting the development of RA in patients with early arthritis as well as in the evaluation of the treatment response. Evidence supports the role of metabolomic analysis as a novel and nontargeted approach for identifying potential biomarkers and for improving the clinical and therapeutical management of patients with chronic inflammatory diseases. Here, we review the metabolic changes occurring in the pathogenesis of RA as well as the implication of the metabolic features in the treatment response.

The inflammation, vascular repair and injury responses to exercise in fit males with and without Type 1 diabetes: an observational study

BACKGROUND

Type 1 diabetes is associated with raised inflammation, impaired endothelial progenitor cell mobilisation and increased markers of vascular injury. Both acute and chronic exercise is known to influence these markers in non-diabetic controls, but limited data exists in Type 1 diabetes. We assessed inflammation, vascular repair and injury at rest and after exercise in physically-fit males with and without Type 1 diabetes.

METHODS

Ten well-controlled type 1 diabetes (27 ± 2 years; BMI 24 ± 0.7 kg.m(2); HbA1c 53.3 ± 2.4 mmol/mol) and nine non-diabetic control males (27 ± 1 years; BMI 23 ± 0.8 kg.m(2)) matched for age, BMI and fitness completed 45-min of running. Venous blood samples were collected 60-min before and 60-min after exercise, and again on the following morning. Blood samples were processed for TNF-α using ELISA, and circulating endothelial progenitor cells (cEPCs; CD45(dim)CD34(+)VEGFR2(+)) and endothelial cells (cECs; CD45(dim)CD133(-)CD34(+)CD144(+)) counts using flow-cytometry.

RESULTS

TNF-α concentrations were 4-fold higher at all-time points in Type 1 diabetes, when compared with control (P < 0.001). Resting cEPCs were similar between groups; after exercise there was a significant increase in controls (P = 0.016), but not in Type 1 diabetes (P = 0.202). CEPCs peaked the morning after exercise, with a greater change in controls vs. Type 1 diabetes (+139 % vs. 27 %; P = 0.01). CECs did not change with exercise and were similar between groups at all points (P > 0.05). Within the Type 1 diabetes group, the delta change in cEPCS from rest to the following morning was related to HbA1c (r = -0.65, P = 0.021) and TNF-α (r = -0.766, P = 0.005).

CONCLUSIONS

Resting cEPCs and cECs in Type 1 diabetes patients with excellent HbA1c and high physical-fitness are comparable to healthy controls, despite eliciting 4-fold greater TNF-α. Furthermore, Type 1 diabetes patients appear to have a blunted post-exercise cEPCs response (vascular repair), whilst a biomarker of vascular injury (cECs) remained comparable to healthy controls.

Reduced levels of circulating progenitor cells in juvenile idiopathic arthritis are counteracted by anti TNF-α therapy

Background

Endothelial progenitor cells (EPC) promote angiogenesis and vascular repair. Though reduced EPC levels have been shown in rheumatoid arthritis, no study has so far evaluated EPCs in children with juvenile idiopathic arthritis (JIA). We aimed to study circulating EPCs in children with JIA, their relation to disease activity, and effects of anti TNF-α treatment.

Methods

Circulating EPCs were quantified by flow cytometry based on CD34, CD133 and KDR expression in peripheral blood of 22 patients with oligoarticular JIA and 29 age-matched controls. EPCs were re-assessed in children with methotrexate-resistant oligo-extended JIA before and up to 12 month after initiation of anti-TNF-alpha therapy. Plasma concentrations of inflammatory and EPC-regulating factors were measured using a multiplex array. Confocal immunofluorescence was used to demonstrate EPCs in synovial tissues.

Results

Children with active JIA showed a significant reduction of relative and absolute counts of circulating progenitor cells and EPCs compared to age-matched healthy controls. CD34⁺ cell levels were modestly and inversely correlated to disease activity. A strong inverse correlation was found between serum TNF-α and EPC levels. In 8 patients treated with anti TNF-α agents, the number of EPCs rose to values similar to healthy controls. CD34⁺KDR⁺ EPCs were found in the synovial tissue of JIA children, but not in control.

Conclusions

Children with JIA have reduced levels of the vasculoprotective and proangiogenic EPCs. While EPCs may contribute to synovial tissue remodelling, EPC pauperization may indicate an excess cardiovascular risk if projected later in life.

Investigation of subclinical atherosclerosis in psoriatic arthritis patients with minimal disease activity

The aim of this study was to investigate the presence of subclinical atherosclerosis among psoriatic arthritis (PsA) patients without any cardiovascular disease (CVD) or traditional cardiovascular risk factors through measurement of endothelial function and carotid intima-media thickness (IMT) and correlated with disease-related risk factors. Twenty patients with PsA according to classification criteria for psoriatic arthritis and 20 age- and sex-matched controls were included. Patients with risk factors for cardiovascular disease were excluded. Carotid IMT was measured using two-dimensional carotid ultrasonography (USG). Endothelial function was determined by measuring flow-mediated endothelial-dependent vasodilatation (FMD %) and nitrate-induced dilatation (NID %) using brachial artery USG. Additionally, serum asymmetric dimethylarginine (ADMA) level was obtained using ELISA methodology. In this cross-sectional study, FMD % was significantly more decreased among PsA patients versus control group [mean 11 % (median (range) %10.5 (8-15 %)] and mean 13.2 % [median (range) 12, 8 % (8.1-17.6 %), respectively; p = 0.01]. There was no significant difference in NID %, ADMA level and mean IMT or maximum IMT results. FMD % did not show a significant correlation with clinical and laboratory data of PsA patients. This study showed that endothelial dysfunction may be present in PsA patients with no CVD and traditional cardiovascular risk factors. The study findings lend support to the previous reports that suggested a potential relationship between PsA and atherosclerotic disorders.