TNFα induces endothelial dysfunction in rheumatoid arthritis via LOX-1 and arginase 2: reversal by monoclonal TNFα antibodies

Exploring endothelial dysfunction in major rheumatic diseases: current trends and future directions

The relationship between rheumatic diseases (RDs) and endothelial dysfunction (ED) is intricate and multifaceted, with chronic inflammation and immune system dysregulation playing key roles. RDs, including Osteoarthritis (OA), Rheumatoid arthritis (RA), Systemic Lupus erythematosus (SLE), Ankylosing spondylitis (AS), Psoriatic arthritis (PsA), Sjogren's syndrome (SS), Systemic sclerosis (SSc), Polymyalgia rheumatica (PMR) are characterized by chronic inflammation and immune dysregulation, leading to ED. ED is marked by reduced nitric oxide (NO) production, increased oxidative stress, and heightened pro-inflammatory and prothrombotic activities, which are crucial in the development of cardiovascular disease (CVD) and systemic inflammation. This association persists even in RD patients without conventional cardiovascular risk factors, suggesting a direct impact of RD-related inflammation on endothelial function. Studies also show that ED significantly contributes to atherosclerosis, thereby elevating cardiovascular risk in RD patients. This review synthesizes the molecular mechanisms connecting major RDs and ED, highlighting potential biomarkers and therapeutic targets. Ultimately, the review aims to enhance understanding of the complex interactions leading to ED in rheumatic patients and inform strategies to mitigate cardiovascular risks and improve patient outcomes.

Cardiovascular Outcomes of Disease-Modifying Antirheumatic Drugs in Rheumatoid Arthritis: A Review of the Current Evidence

Rheumatoid arthritis (RA) significantly increases the risk of cardiovascular disease (CVD), including myocardial infarction (MI), stroke, and heart failure (HF), with RA treatments influencing cardiovascular outcomes. This review analyses the cardiovascular effects of methotrexate, leflunomide, hydroxychloroquine, sulfasalazine, and TNF inhibitors (infliximab, etanercept, adalimumab, and certolizumab) in RA management, emphasizing their safety and risks in CVD. This narrative literature review was conducted using searches of the PubMed database from inception through January 2025. We included meta-analyses, systematic reviews, randomized controlled trials, observational studies, pharmacovigilance studies, and animal studies. Methotrexate offers cardiovascular benefits by reducing inflammation and improving endothelial function. However, it also raises homocysteine levels, which promote oxidative stress and endothelial injury - effects that can be mitigated by folic acid supplementation. Leflunomide's cardiovascular effects remain poorly defined, highlighting the need for further research. Hydroxychloroquine may prolong the QT interval, raising the risk of conduction disorders and necessitating monitoring in high-risk patients. Sulfasalazine shows potential cardiovascular benefits by inhibition of platelet aggregation, improved endothelial function, and reduced lipid levels, although more research is needed for conclusive evidence. TNF inhibitors, such as infliximab, etanercept, adalimumab, and certolizumab pegol, reduce inflammation-driven cardiovascular risks but are contraindicated in patients with severe HF (New York Heart Association [NYHA] classes III and IV).

Cardiovascular Adverse Events Associated with Tumor Necrosis Factor-Alpha Inhibitors: A Real-World Pharmacovigilance Analysis

AIM

Evidence regarding the association between various tumor necrosis factor-α (TNF-α) inhibitors and cardiovascular adverse events (AEs) is both limited and contradictory.

METHODS

A retrospective pharmacovigilance study was conducted using the FDA Adverse Event Reporting System (FAERS) database. Cardiovascular AEs associated with TNF-α inhibitors (adalimumab, infliximab, etanercept, golimumab, and certolizumab) were evaluated using a disproportionality analysis. To reduce potential confounders, adjusted ROR and subgroup analyses were performed.

RESULTS

After excluding duplicates, 9,817 cardiovascular reports were associated with the five TNF-α inhibitors. Only adalimumab had positive signals for myocardial infarction (ROR=1.58, 95%CI=1.51-1.64) and arterial thrombosis (ROR=1.54, 95%CI=1.49-1.58). The remaining four TNF-α inhibitors did not show a risk association with any type of cardiovascular event. Further analyses of specific indication subgroups and after adjusting for any confounding factors demonstrated that adalimumab was still significantly associated with cardiovascular events, especially in patients with psoriasis (adjusted ROR=2.16, 95%CI=1.95-2.39).

CONCLUSIONS

This study revealed that adalimumab was the only TNF-α inhibitor associated with an elevated risk of thrombotic cardiovascular AEs, whereas the other four TNF-α inhibitors did not show any risk effect. However, given the limitations of such pharmacovigilance studies, it is necessary to validate these findings in prospective studies in the future.

Autoimmune diseases and atherosclerotic cardiovascular disease

Autoimmune diseases are associated with a dramatically increased risk of atherosclerotic cardiovascular disease and its clinical manifestations. The increased risk is consistent with the notion that atherogenesis is modulated by both protective and disease-promoting immune mechanisms. Notably, traditional cardiovascular risk factors such as dyslipidaemia and hypertension alone do not explain the increased risk of cardiovascular disease associated with autoimmune diseases. Several mechanisms have been implicated in mediating the autoimmunity-associated cardiovascular risk, either directly or by modulating the effect of other risk factors in a complex interplay. Aberrant leukocyte function and pro-inflammatory cytokines are central to both disease entities, resulting in vascular dysfunction, impaired resolution of inflammation and promotion of chronic inflammation. Similarly, loss of tolerance to self-antigens and the generation of autoantibodies are key features of autoimmunity but are also implicated in the maladaptive inflammatory response during atherosclerotic cardiovascular disease. Therefore, immunomodulatory therapies are potential efficacious interventions to directly reduce the risk of cardiovascular disease, and biomarkers of autoimmune disease activity could be relevant tools to stratify patients with autoimmunity according to their cardiovascular risk. In this Review, we discuss the pathophysiological aspects of the increased cardiovascular risk associated with autoimmunity and highlight the many open questions that need to be answered to develop novel therapies that specifically address this unmet clinical need.

Inhibition of de novo ceramide synthesis by sirtuin-1 improves beta-cell function and glucose metabolism in type 2 diabetes

AIMS

Obesity and type 2 diabetes (T2D) are major risk factors for cardiovascular (CV) diseases. Dysregulated pro-apoptotic ceramide synthesis reduces β-cell insulin secretion, thereby promoting hyperglycaemic states that may manifest as T2D. Pro-apoptotic ceramides modulate insulin sensitivity and glucose tolerance while being linked to poor CV outcomes. Sirtuin-1 (SIRT1) is a NAD + -dependent deacetylase that protects against pancreatic β-cell dysfunction; however, systemic levels are decreased in obese-T2D mice and may promote pro-apoptotic ceramide synthesis and hyperglycaemia. Herein, we aimed to assess the effects of restoring circulating SIRT1 levels to prevent metabolic imbalance in obese and diabetic mice.

METHODS AND RESULTS

Circulating SIRT1 levels were reduced in obese-diabetic mice (db/db) as compared to age-matched non-diabetic db/+ controls. Restoration of SIRT1 plasma levels with recombinant murine SIRT1 for 4 weeks prevented body weight gain and improved glucose tolerance, insulin sensitivity, and vascular function in mice models of obesity and T2D. Untargeted lipidomics revealed that SIRT1 restored insulin secretory function of β-cells by reducing synthesis and accumulation of pro-apoptotic ceramides. Molecular mechanisms involved direct binding to and deacetylation of Toll-like receptor 4 (TLR4) by SIRT1 in β-cells, thereby decreasing the rate-limiting enzymes of sphingolipid synthesis SPTLC1/2 via AKT/NF-κB. Among patients with T2D, those with high baseline plasma levels of SIRT1 prior to metabolic surgery displayed restored β-cell function (HOMA2-β) and were more likely to have T2D remission during follow-up.

CONCLUSION

Acetylation of TLR4 promotes β-cell dysfunction via ceramide synthesis in T2D, which is blunted by systemic SIRT1 replenishment. Hence, restoration of systemic SIRT1 may provide a novel therapeutic strategy to counteract toxic ceramide synthesis and mitigate CV complications of T2D.

Associations of Rheumatoid Factor, Rheumatoid Arthritis, and Interleukin-6 Inhibitor with the Prognosis of Ischemic Stroke: a Prospective Multicenter Cohort Study and Mendelian Randomization Analysis

Rheumatoid factor (RF), an established diagnostic biomarker for rheumatoid arthritis (RA), is associated with cardiovascular diseases, but its impact on clinical outcomes of ischemic stroke remains unclear. We aimed to investigate the observational associations between serum RF and prognosis of ischemic stroke, and further examined the genetic associations of RA and its therapeutic strategy, interleukin-6 (IL-6) inhibitor, with prognosis of ischemic stroke. We measured serum RF levels in 3474 Chinese ischemic stroke patients from the China Antihypertensive Trial in Acute Ischemic Stroke. The primary outcome was the composite outcome of death or major disability (modified Rankin Scale score ≥3) at 3 months after stroke onset. Mendelian randomization (MR) analyses were performed to examine the associations of genetically predicted RA and IL-6 inhibition with prognosis of ischemic stroke. During 3 months of follow-up, 866 patients (25.43%) experienced death or major disability. After multivariate adjustment, RF-positive was significantly associated with a high risk of primary outcome (OR, 1.47; 95% CI, 1.08-2.00; P =0.016) compared with RF-negative. The two-sample MR analyses suggested that genetically predicted RA was associated with an increased risk of primary outcome (OR, 1.09; 95% CI, 1.01-1.18; P=0.021), while genetically predicted IL-6 inhibition was associated with a decreased risk of primary outcome (OR, 0.88; 95% CI, 0.77-0.99; P=0.041). We found that positive RF was associated with increased risks of adverse outcomes after atherosclerotic ischemic stroke, and genetically predicted RA and IL-6 inhibition increased and decreased the risks of adverse outcomes after ischemic stroke, respectively.

Personalized cardiovascular risk assessment in Rheumatoid Arthritis patients using circulating molecular profiles and their modulation by TNFi, IL6Ri, and JAKinibs

BACKGROUND & OBJECTIVES

This study aimed to: 1) analyze the inflammatory profile of Rheumatoid Arthritis (RA) patients, identifying clinical phenotypes associated with cardiovascular (CV) risk; 2) evaluate biologic and targeted-synthetic disease-modifying antirheumatic drugs (b-DMARDs and ts-DMARDs': TNFi, IL6Ri, JAKinibs) effects; and 3) characterize molecular mechanisms in immune-cell activation and endothelial dysfunction.

PATIENTS & METHODS

A total of 387 RA patients and 45 healthy donors were recruited, forming three cohorts: i) 208 RA patients with established disease but without previous CV events; ii) RA-CVD: 96 RA patients with CV events, and iii) 83 RA patients treated with b-DMARDs/ts-DMARDs for 6 months. Serum inflammatory profiles (cytokines/chemokines/growth factors) and NETosis/oxidative stress-linked biomolecules were evaluated. Mechanistic in vitro studies were performed on monocytes, neutrophils and endothelial cells (EC).

RESULTS

In the first RA-cohort, unsupervised clustering unveiled three distinct groups: cluster 3 (C3) displayed the highest inflammatory profile, significant CV-risk score, and greater atheroma plaques prevalence. In contrast, cluster 1 (C1) exhibited the lowest inflammatory profile and CV risk score, while cluster 2 (C2) displayed an intermediate phenotype. Notably, 2nd cohort RA-CVD patients mirrored C3's inflammation. Treatment with b-DMARDs or ts-DMARDs effectively reduced disease-activity scores (DAS28) and restored normal biomolecules levels, controlling CV risk. In vitro, serum from C3-RA or RA-CVD patients increased neutrophils activity and CV-related protein levels in cultured monocytes and EC, which were partially prevented by pre-incubation with TNFi, IL6Ri, and JAKinibs.

CONCLUSIONS

Overall, analyzing circulating molecular profiles in RA patients holds potential for personalized clinical management, addressing CV risk and assisting healthcare professionals in tailoring treatment, ultimately improving outcomes.

Knockdown of LOX-1 ameliorates bone quality and generation of type H blood vessels in diabetic mice

Our previous studies have shown that lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) is expressed in liver sinusoidal endothelial cells, and oxidized low-density lipoprotein induces liver sinusoidal dysfunction and defenestration through the LOX-1/ROS/NF-kB pathway, revealing that LOX-1 can mediate liver sinusoidal barrier function, involved in the regulation of non-alcoholic fatty liver disease. Here, we investigated whether, in the context of bone metabolic diseases, LOX-1 could affect bone quality and type H blood vessels in diabetic mice. We used db/db mice as model and found that LOX-1 knockdown can ameliorate bone quality and type H blood vessel generation in db/db mice. This further verifies our hypothesis that LOX-1 is involved in the regulation of bone quality and type H blood vessel homeostasis, thus inhibiting osteoporosis progression in db/db mice.

Stroke risk in rheumatoid arthritis patients: exploring connections and implications for patient care

Rheumatoid arthritis (RA) can independently increase the risk of stroke, affecting both young and adult RA patients. Recent attention has been drawn to the association between stroke and RA, supported by mounting evidence. Given that stroke is a significant and an urgent public health concern, this review aims to highlight the relationship between stroke and RA, covering mechanisms, underlying risk factors, early detection tools, and treatment implications. By uncovering the connection that links RA to stroke, we can pave the way for targeted healthcare practices and the development of preventive strategies for individuals with RA. Therefore, further research is imperative to deepen our understanding of this association and, ideally, guide treatment decisions for individuals at risk of both RA and stroke.

Anemia in elderly rheumatoid arthritis patients: a cohort study

Introduction

Anemia is common in elderly patients with rheumatoid arthritis (RA). This study aimed to evaluate the current status and influencing factors of anemia in RA patients, to provide insights for clinical RA treatment and care.

Material and methods

This study included elderly patients with high RA activity treated in our hospital from June 1, 2021 to December 31, 2022 for analysis. The characteristics of RA patients were analyzed. Pearson correlation and logistic regression analysis were conducted to analyze the influencing factors of anemia in elderly patients with RA.

Results

A total of 285 RA patients were included. The incidence of anemia in high RA activity patients was 62.46%. There were significant differences in the course of RA, hemoglobin (Hb), low-density lipoprotein cholesterol (LDL-C), platelet/lymphocyte rate (PLR) and albumin (Alb) between RA patients with anemia and without anemia (all p < 0.05). Pearson correlation analysis indicated that course of RA (r = 0.522), Hb (r = 0.797), LDL-C (r = 0.558), PLR (r = 0.615) and Alb (r = 0.604) were correlated with anemia in patients with high RA activity (all p < 0.05). Logistic regression analysis indicated that course of RA ≥ 8 years (OR = 2.584, 95% CI: 1.822-3.647), LDL-C ≤ 2.8 mmol/l (OR = 3.202, 95% CI: 2.804-3.431), PLR ≥ 8 (OR = 2.183, 95% CI: 1.744-2.457), Alb ≤ 35 g/l (OR = 1.716, 95% CI: 1.401-2.006) were the risk factors of anemia in elderly patients with high RA activity (all p < 0.05).

Conclusions

Anemia in elderly patients with high RA activity is closely related to the course of RA, LDL-C, PLR and Alb. Close attention should be paid to the monitoring of those indicators to take early intervention measures to improve the prognosis of RA patients.

The Notch signaling-regulated angiogenesis in rheumatoid arthritis: pathogenic mechanisms and therapeutic potentials

Angiogenesis plays a key role in the pathological process of inflammation and invasion of the synovium, and primarily drives the progression of rheumatoid arthritis (RA). Recent studies have demonstrated that the Notch signaling may represent a new therapeutic target of RA. Although the Notch signaling has been implicated in the M1 polarization of macrophages and the differentiation of lymphocytes, little is known about its role in angiogenesis in RA. In this review, we discourse the unique roles of stromal cells and adipokines in the angiogenic progression of RA, and investigate how epigenetic regulation of the Notch signaling influences angiogenesis in RA. We also discuss the interaction of the Notch-HIF signaling in RA's angiogenesis and the potential strategies targeting the Notch signaling to improve the treatment outcomes of RA. Taken together, we further suggest new insights into future research regarding the challenges in the therapeutic strategies of RA.

The Association Between Rheumatoid Arthritis and Atrial Fibrillation: Epidemiology, Pathophysiology and Management

Atrial fibrillation (AF) is the most common cardiac arrhythmia with a significant increase in morbidity and mortality worldwide. Rheumatoid arthritis (RA), as a systemic inflammatory disease, affecting 0.5-1.0% of the adult population, is associated with increased incidence of cardiac arrhythmias such as AF. Several epidemiologic studies find that the risk of AF is increased in RA when compared with the general population. Other studies are inconsistent. Considering that inflammation plays an important role in AF, RA may be involved in the occurrence and development of AF. This review summarizes the epidemiology, pathophysiology, and management of AF in patients with RA.

Pathogenesis of Extraarticular Manifestations in Rheumatoid Arthritis-A Comprehensive Review

Rheumatoid arthritis (RA) is among the most prevalent and debilitating autoimmune inflammatory chronic diseases. Although it is primarily characterized by destructive peripheral arthritis, it is a systemic disease, and RA-related extraarticular manifestations (EAMs) can affect almost every organ, exhibit a multitude of clinical presentations, and can even be asymptomatic. Importantly, EAMs largely contribute to the quality of life and mortality of RA patients, particularly substantially increased risk of cardiovascular disease (CVD) which is the leading cause of death in RA patients. In spite of known risk factors related to EAM development, a more in-depth understanding of its pathophysiology is lacking. Improved knowledge of EAMs and their comparison to the pathogenesis of arthritis in RA could lead to a better understanding of RA inflammation overall and its initial phases. Taking into account that RA is a disorder that has many faces and that each person experiences it and responds to treatments differently, gaining a better understanding of the connections between the joint and extra-joint manifestations could help to create new treatments and improve the overall approach to the patient.

The Impact of Cytokines in Coronary Atherosclerotic Plaque: Current Therapeutic Approaches

Coronary atherosclerosis is a chronic pathological process that involves inflammation together with endothelial dysfunction and lipoprotein dysregulation. Experimental studies during the past decades have established the role of inflammatory cytokines in coronary artery disease, namely interleukins (ILs), tumor necrosis factor (TNF)-α, interferon-γ, and chemokines. Moreover, their value as biomarkers in disease development and progression further enhance the validity of this interaction. Recently, cytokine-targeted treatment approaches have emerged as potential tools in the management of atherosclerotic disease. IL-1β, based on the results of the CANTOS trial, remains the most validated option in reducing the residual cardiovascular risk. Along the same line, colchicine was also proven efficacious in preventing major adverse cardiovascular events in large clinical trials of patients with acute and chronic coronary syndrome. Other commercially available agents targeting IL-6 (tocilizumab), TNF-α (etanercept, adalimumab, infliximab), or IL-1 receptor antagonist (anakinra) have mostly been assessed in the setting of other inflammatory diseases and further testing in atherosclerosis is required. In the future, potential targeting of the NLRP3 inflammasome, anti-inflammatory IL-10, or atherogenic chemokines could represent appealing options, provided that patient safety is proven to be of no concern.

Hydroxychloroquine Alleviates EAU by Inhibiting Uveitogenic T Cells and Ameliorating Retinal Vascular Endothelial Cells Dysfunction

Purpose

Inflammation triggers the activation of CD4⁺T cells and the breakdown of blood–retinal barrier, thus contributing to the pathology of experimental autoimmune uveitis (EAU). We explored the anti-inflammatory effect of hydroxychloroquine (HCQ) on EAU and the potential mechanisms active in T cells and retinal vascular endothelial cells (RVECs).

Methods

C57BL/6J mice were immunized with interphotoreceptor retinoid binding protein 1-20 (IRBP_1–20) to induce EAU and then treated with the vehicle or HCQ (100 mg/kg/day). On day 7, 14, 21, 30 and 60 after immunization, clinical scores were evaluated. On day 14, histopathological scores were assessed, and retinas, spleens, and lymph nodes were collected for quantitative polymerase chain reaction or flow cytometry analysis. RVEC dysfunction was induced by tumor necrosis factor α (TNF-α) stimulation. The expression of cytokines, chemokines, adhesion molecules, and lectin-like oxidized LDL receptor-1 (LOX-1)/nuclear factor κB (NF-κB) was measured in RVECs with or without HCQ.

Results

HCQ treatment protected mice from uveitis, evidenced by reduced expression of inflammatory factors, chemokines, and adhesion molecules in the retina. In systemic immune response, HCQ inhibited the activation of naïve CD4⁺T cells and frequencies of T effector cells, and promoted T regulatory cells. HCQ decreased IRBP_1-20–specific T cell responses and proliferation of CD4⁺T cells in vitro. Further studies established that TNF-α induced RVECs to express inflammatory cytokines, chemokines, and adhesion molecules, whereas HCQ alleviated the alterations via the LOX-1/NF-κB pathways.

Conclusions

HCQ alleviates EAU by regulating the Teff/Treg balance and ameliorating RVECs dysfunction via the LOX-1/NF-κB axis. HCQ may be a promising therapeutic candidate for uveitis.

Treatment of Cardiovascular Disease in Rheumatoid Arthritis: A Complex Challenge with Increased Atherosclerotic Risk

Rheumatoid arthritis (RA) carries significant risk for atherosclerotic cardiovascular disease (ASCVD). Traditional ASCVD risk factors fail to account for this accelerated atherosclerosis. Shared inflammatory pathways are fundamental in the pathogenesis of both diseases. Considering the impact of RA in increasing cardiovascular morbidity and mortality, the characterization of therapies encompassing both RA and ASCVD management merit high priority. Despite little progress, several drugs discussed here promote remission and or lower rheumatoid disease activity while simultaneously conferring some level of atheroprotection. Methotrexate, a widely used disease-modifying drug used in RA, is associated with significant reduction in cardiovascular adverse events. MTX promotes cholesterol efflux from macrophages, upregulates free radical scavenging and improves endothelial function. Likewise, the sulfonamide drug sulfasalazine positively impacts the lipid profile by increasing HDL-C, and its use in RA has been correlated with reduced risk of myocardial infraction. In the biologic class, inhibitors of TNF-α and IL-6 contribute to improvements in endothelial function and promote anti-atherogenic properties of HDL-C, respectively. The immunosuppressant hydroxychloroquine positively affects insulin sensitization and the lipid profile. While no individual therapy has elicited optimal atheroprotection, further investigation of combination therapies are ongoing.