Targeting Systemic Sclerosis from Pathogenic Mechanisms to Clinical Manifestations: Why IL-6?

Focusing on Arterial and Cardiac Dysfunction in Systemic Sclerosis: Targeted Therapy is Still Pending

Although the pathophysiology and therapy of microvascular damage was so far addressed by both rheumatologists and angiologists, cardiac disease related to Systemic sclerosis (SSc) remained obscure or misdiagnosed for long time. Although its pathogenetic chain is far to be completely understood, myocardial fibrosis and microvascular dysfunction play a prominent role in the clinical history of patients with SSc. Bearing in mind that it is one of the main causes of death and disabilities for SSc patients, an early screening has become mandatory at time of diagnosis, and then every year during the follow-up. Moreover, the prevalence of coronary heart disease in SSc resulted comparable, in older patients, to that of patients with type 2 diabetics. Global longitudinal strain (GLS), a well-known early echocardiographic marker of cardiac dysfunction, has been recently shown to be a useful tool predicting prognosis and effects of therapy in SSc. Target therapy for primary cardiac disease in SSc is so far not well established. Inhibitor of IL-1 and IL-6 are under investigation. The acute infusion of iloprost ameliorates the baseline depressed GLS of left ventricle in patients with SSc, but this beneficial effect remains to be confirmed during chronic treatment.

Markers of Endotoxemia and Inflammation are Associated with Digital Ulcers in Systemic Sclerosis Patients

BACKGROUND

The aim of this study was to evaluate the possible role of lipopolysaccharide-binding protein (LBP) and interleukin 6 (IL-6) in the development of digital ulcers (DUs) in Systemic sclerosis (SSc).

METHODS

60 SSc patients were enrolled and tested for serum levels of LBP and IL-6. The development of DUs was assessed in a 12-month follow-up period.

RESULTS

Median LBP and IL-6 were 107.445 ng/mL and 10.8 pg/mL whilst 33.3% patients had LBP ≥ 11995 ng/mL and 51.7% patients had IL-6 ≥ 12.5 pg/mL. DUs history were present in 41.7% SSc patients and at follow-up 23.3% patients developed new DUs. Baseline LBP (14105 ng/mL vs 10355 ng/mL, p < .001) and IL-6 (195 pg/mL vs 9.4 ng/mL, p < .001) were higher in SSc patients with new DUs. The ROC curves showed a good diagnostic accuracy for a cut-off of LBP ≥ 11995 ng/mL [AUC = 0.804 (95% CI = 0.656-0.951), p < .001] and for a cut-off of IL-6 ≥ 12.5 pg/mL [AUC = 0.897 (95% CI = 0.783-1.000), p < .001]. Free survival from new DUs was shorter in SSc patients with increased LBP (p < .001) or IL-6 (p = .003).

CONCLUSIONS

LPB or IL-6 could play a role in digital microvascular damage of SSc patients.

Oral submucous fibrosis: pathogenesis and therapeutic approaches

Oral submucous fibrosis (OSF), characterized by excessive deposition of extracellular matrix (ECM) that causes oral mucosal tissue sclerosis, and even cancer transformation, is a chronic, progressive fibrosis disease. However, despite some advancements in recent years, no targeted antifibrotic strategies for OSF have been approved; likely because the complicated mechanisms that initiate and drive fibrosis remain to be determined. In this review, we briefly introduce the epidemiology and etiology of OSF. Then, we highlight how cell-intrinsic changes in significant structural cells can drive fibrotic response by regulating biological behaviors, secretion function, and activation of ECM-producing myofibroblasts. In addition, we also discuss the role of innate and adaptive immune cells and how they contribute to the pathogenesis of OSF. Finally, we summarize strategies to interrupt key mechanisms that cause OSF, including modulation of the ECM, inhibition of inflammation, improvement of vascular disturbance. This review will provide potential routes for developing novel anti-OSF therapeutics.

Fibrosis mechanisms in systemic sclerosis and new potential therapies

Systemic sclerosis is a rare rheumatic disease characterized by immune cell activation, tissue fibrosis, and endothelial dysfunction. Extracellular matrix synthesis disorder causes widespread fibrosis, primarily in skin and internal organs. Various factors such as TGFβ, VEGF, Galectin-3, and signaling pathways like Wnt/β-catenin are involved in pathophysiological processes. Treatment lacks a unified approach but combines diverse modalities tailored to disease subtype and progression. Current therapeutic strategies include biologics, JAK inhibitors, and IL-6 pathway modulators. Monoclonal antibodies and hypomethylating agents demonstrate potential in fibrosis inhibition. This review focuses on emerging therapeutic evidence regarding drugs targeting collagen, cytokines, and cell surface molecules in systemic sclerosis, aiming to provide insight into potential innovative treatment strategies.

What Is New in Morphea-Narrative Review on Molecular Aspects and New Targeted Therapies

Morphea, also known as localized scleroderma, is an autoimmune chronic connective tissue disease. It is characterized by excessive collagen deposition in the dermis and/or subcutaneous tissue. The etiopathogenesis of this disease is not fully understood, with endothelial cell damage, immunological disorders, extracellular matrix disorders and factors such as infection, trauma and other autoimmune diseases being considered. As medicine advances, there is increasing evidence that genetic factors play a significant role in disease risk and progression. In addition to environmental factors and genetic predisposition, epigenetic factors may be potential triggers for morphea. Epigenetics studies changes that affect gene expression without altering the DNA sequence, such as microRNAs, long non-coding RNAs or DNA methylation. Understanding the pathogenesis of this disease is key to identifying potential new treatments. There are anecdotal reports of good therapeutic effects following the use of biological drugs such as tocilizumab, a humanized IgG monoclonal antibody; abatacept, a recombinant soluble fusion protein; JAK inhibitors, such as tofacitinib and baricitinib; and a drug used successfully in cancer treatment, imatinib, a tyrosine kinase receptor inhibitor. In this article, we aim to review up-to-date knowledge on the pathogenesis of morphea, with particular emphasis on genetic and epigenetic factors. In addition, we present the new options of morphea treatment based on several case series treated with new drugs that are potential targets for the development of therapies for this disease.

Immunotherapy for Pulmonary Arterial Hypertension: From the Pathogenesis to Clinical Management

Pulmonary hypertension (PH) is a progressive cardiovascular disease, which may lead to severe cardiopulmonary dysfunction. As one of the main PH disease groups, pulmonary artery hypertension (PAH) is characterized by pulmonary vascular remodeling and right ventricular dysfunction. Increased pulmonary artery resistance consequently causes right heart failure, which is the major reason for morbidity and mortality in this disease. Although various treatment strategies have been available, the poor clinical prognosis of patients with PAH reminds us that further studies of the pathological mechanism of PAH are still needed. Inflammation has been elucidated as relevant to the initiation and progression of PAH, and plays a crucial and functional role in vascular remodeling. Many immune cells and cytokines have been demonstrated to be involved in the pulmonary vascular lesions in PAH patients, with the activation of downstream signaling pathways related to inflammation. Consistently, this influence has been found to correlate with the progression and clinical outcome of PAH, indicating that immunity and inflammation may have significant potential in PAH therapy. Therefore, we reviewed the pathogenesis of inflammation and immunity in PAH development, focusing on the potential targets and clinical application of anti-inflammatory and immunosuppressive therapy.

Trace Element Deficiency in Systemic Sclerosis-Too Much Effort for Some Traces?

Trace elements are essential for several physiological processes. To date, various data have suggested that inadequate levels of trace elements may be involved in the pathogenesis of different chronic diseases, including immune-mediated ones, or may develop during their course. Systemic sclerosis (SSc) is a complex autoimmune multisystemic disease, primarily characterized by microvascular dysregulation, the widespread activation of the immune system and tissue fibrosis. According to the latest reports regarding the pathogenesis of SSc, the main pathophysiological processes-inflammation, vasculopathy and fibrosis-may include various trace element derangements. The present literature review aims to update the available data regarding iron, zinc, copper and selenium status in SSc as well as to underline the possible implications of these trace elements in the complexity of the pathogenic process of the disease. We observe that the status of trace elements in SSc plays a crucial role in numerous pathogenic processes, emphasizing the necessity for proper monitoring and supplementation. The reported data are heterogenous and scarce, and future studies are needed in order to draw clearer conclusions about their complete spectrum.

Systemic scleroderma: Review and updated approach and case description to addressing pulmonary arterial hypertension and idiopathic pulmonary fibrosis: A dual challenge in treatment

Pulmonary arterial hypertension (PAH), idiopathic pulmonary fibrosis (IPF), and scleroderma (SSc) are three interrelated medical conditions that can result in significant morbidity and mortality. Pulmonary hypertension, a condition marked by high blood pressure in the lungs, can lead to heart failure and other complications. Idiopathic pulmonary fibrosis, a progressive lung disease characterised by scarring of lung tissue, can cause breathing difficulties and impaired oxygenation. Scleroderma, an autoimmune disease, can induce thickening and hardening of the skin and internal organs, including the lungs, leading to pulmonary fibrosis and hypertension. Currently, there is no cure for any of these conditions. However, early detection and proper management can improve the quality of life and prognosis of a patient. This review focusses on PH and IPF in patients with SSc, providing information on the causes, symptoms, and treatment of these conditions, together with illustrative images. It also provides an overview of interrelated medical conditions: PH, IPF, and SSc. It emphasises the importance of early detection and proper management to improve patient quality of life and prognosis.

Tocilizumab in systemic sclerosis treatment: a case report

Introduction

In the United States, tocilizumab was approved for the treatment of scleroderma and scleroderma-related interstitial lung disease because it inhibited the decrease in forced expiratory volume, so scleroderma treatment is entering a new era.

Case presentation

A 44-year-old female patient with systemic scleroderma, diagnosed 6 years ago, presented with breathlessness over the last week. The modified Rodnan's score was 18. Tocilizumab 162 mg subcutaneously once every 2 weeks was prescribed. After 4 weeks, a decrease in Rodnan score was observed. Tocilizumab was stopped after 6 months without any side effects due to treatment.

Discussion

Treatment with tocilizumab may maintain lung function nearly unchanged. Its effect on perfecting skin fibrosis seems promising. Tocilizumab may be fairly safe to use.

Conclusion

Tocilizumab may be effective and fairly safe to use. Further exploration is anticipated to advance a new period of systemic sclerosis treatment.

Scleroderma pulmonary arterial hypertension: the same as idiopathic pulmonary arterial hypertension?

PURPOSE OF REVIEW

Pulmonary arterial hypertension (PAH) is a common complication of systemic sclerosis (SSc), which confers significant morbidity and mortality. The current therapies and treatment strategies for SSc-associated PAH (SSc-PAH) are informed by those used to treat patients with idiopathic PAH (IPAH). There are, however, important differences between these two diseases that impact diagnosis, treatment, and outcomes.

RECENT FINDINGS

Both SSc-PAH and IPAH are incompletely understood with ongoing research into the underlying cellular biology that characterize and differentiate the two diseases. Additional research seeks to improve identification among SSc patients in order to diagnose patients earlier in the course of their disease. Novel therapies specifically for SSc-PAH such as rituximab and dimethyl fumarate are under investigation.

SUMMARY

Although patients with SSc-PAH and IPAH present with similar symptoms, there are significant differences between these two forms of PAH that warrant further investigation and characterization of optimal detection strategies, treatment algorithms, and outcomes assessment.

Recent advances in strategies to target the behavior of macrophages in wound healing

Chronic wounds and scar formation are widespread due to limited suitable remedies. The macrophage is a crucial regulator in wound healing, controlling the onset and termination of inflammation and regulating other processes related to wound healing. The current breakthroughs in developing new medications and drug delivery methods have enabled the accurate targeting of macrophages in oncology and rheumatic disease therapies through clinical trials. These successes have cleared the way to utilize drugs targeting macrophages in various disorders. This review thus summarizes macrophage involvement in normal and pathologic wound healing. It further details the targets available for macrophage intervention and therapeutic strategies for targeting the behavior of macrophages in tissue repair and regeneration.

Pharmacotherapies in Dupuytren Disease: Current and Novel Strategies

Dupuytren disease is a benign, progressive fibroproliferative disorder of the hands. To date, only one pharmacotherapy (clostridial collagenase) has been approved for use in Dupuytren disease. There is a great need for additional nonsurgical methods that can be used to either avoid the risks of invasive treatments or help minimize recurrence rates following treatment. A number of nonsurgical modalities have been discussed in the past and continue to appear in discussions among hand surgeons, despite highly variable and often poor or no long-term clinical data. This article reviews many of the pharmacotherapies discussed in the treatment of Dupuytren disease and novel therapies used in inflammation and fibrosis that offer potential treatment options.

The Role of Macrophages in Connective Tissue Disease-Associated Interstitial Lung Disease: Focusing on Molecular Mechanisms and Potential Treatment Strategies

Connective tissue disease-associated interstitial lung disease (CTD-ILD) is a severe manifestation of CTD that leads to significant morbidity and mortality. Clinically, ILD can occur in diverse CTDs. Pathologically, CTD-ILD is characterized by various histologic patterns, such as nonspecific interstitial pneumonia, organizing pneumonia, and usual interstitial pneumonia. Abnormal immune system responses have traditionally been instrumental in its pathophysiology, and various changes in immune cells have been described, especially in macrophages. This article first briefly overviews the epidemiology, clinical characteristics, impacts, and histopathologic changes associated with CTD-ILD. Next, it summarizes the roles of various signaling pathways in macrophages or products of macrophages in ILD, helped by insights gained from animal models. In the following sections, this review returns to studies of macrophages in CTD-ILD in humans for an overall picture of the current understanding. Finally, we direct attention to potential therapies targeting macrophages in CTD-ILD in investigation or in clinical trials, as well as the future directions regarding macrophages in the context of CTD-ILD. Although the field of macrophages in CTD-ILD is still in its infancy, several lines of evidence suggest the potential of this area.

Interleukin-6 and pulmonary hypertension: from physiopathology to therapy

Pulmonary hypertension (PH) is a progressive, pulmonary vascular disease with high morbidity and mortality. Unfortunately, the pathogenesis of PH is complex and remains unclear. Existing studies have suggested that inflammatory factors are key factors in PH. Interleukin-6 (IL-6) is a multifunctional cytokine that plays a crucial role in the regulation of the immune system. Current studies reveal that IL-6 is elevated in the serum of patients with PH and it is negatively correlated with lung function in those patients. Since IL-6 is one of the most important mediators in the pathogenesis of inflammation in PH, signaling mechanisms targeting IL-6 may become therapeutic targets for this disease. In this review, we detailed the potential role of IL-6 in accelerating PH process and the specific mechanisms and signaling pathways. We also summarized the current drugs targeting these inflammatory pathways to treat PH. We hope that this study will provide a more theoretical basis for targeted treatment in patients with PH in the future.

The Clinical Significance of Serum Biomarkers of the Intestinal Barrier in Systemic Sclerosis: A Cross-Sectional Study

Systemic sclerosis (SSc) is an immune-mediated connective tissue disease. Recent studies reported differences in the composition of intestinal microbiota (dysbiosis) in patients with SSc compared to nonsclerodermic subjects. Dysbiosis may disrupt the intestinal barrier, which leads to immunological activation via microbial antigen and metabolite translocation. The study aimed to assess the differences in intestinal permeability between SSc patients and controls and to examine the correlation between intestinal permeability and complications of SSc. The study comprised 50 patients with SSc and 30 matched subjects. Serum intestinal permeability markers: intestinal fatty acid binding protein, claudin-3, and lipopolysaccharides (LPS) were determined using an enzyme-linked immunosorbent assay. SSc patients had a significantly increased concentration of LPS compared to control subjects (232.30 [149.00-347.70] versus 161.00 [83.92-252.20] pg/mL, p < 0.05). The patients with shorter SSc duration (≤6 years) had an increased concentration of LPS and claudin-3 compared to the subgroup with longer disease length: LPS (280.75 [167.30-403.40] versus 186.00 [98.12-275.90] pg/mL, p < 0.05), and claudin-3 (16.99 [12.41-39.59] versus 13.54 [10.29-15.47] ng/mL, p < 0.05). The patients with esophageal dysmotility had a decreased LPS level compared to those without this complication (188.05 [102.31-264.40] versus 283.95 [203.20-356.30] pg/mL, p < 0.05). Increased intestinal permeability in SSc may exacerbate the course of the disease and increase the risk of developing complications. Lower LPS levels in SSc might be a hallmark of esophageal dysmotility.

Morphea: The 2023 update

Morphea, also known as localized scleroderma, is a chronic inflammatory connective tissue disorder with variable clinical presentations, that affects both adults and children. It is characterized by inflammation and fibrosis of the skin and underlying soft tissue, in certain cases even of the surrounding structures such as fascia, muscle, bone and central nervous system. While the etiology is still unknown, many factors may contribute to disease development, including genetic predisposition, vascular dysregulation, T_H1/T_H2 imbalance with chemokines and cytokines associated with interferon-γ and profibrotic pathways as well as certain environmental factors. Since the disease may progress to permanent cosmetic and functional sequelae, it is crucial to properly assess the disease activity and to initiate promptly the adequate treatment, thus preventing subsequent damage. The mainstay of treatment is based on corticosteroids and methotrexate. These, however, are limited by their toxicity, especially if applied long-term. Furthermore, corticosteroids and methotrexate often do not sufficiently control the disease and/or the frequent relapses of morphea. This review presents the current understanding of morphea by discussing its epidemiology, diagnosis, management and prognosis. In addition, it will describe recent pathogenetic findings, thus proposing potential novel targets for therapeutic development in morphea.

cGAS deficiency enhances inflammasome activation in macrophages and inflammatory pathology in pristane-induced lupus

Introduction

Type I interferon (IFN) plays a vital role in the pathogenesis of systemic lupus erythematosus. Cyclic GMP AMP synthase (cGAS) is a cytosolic DNA sensor that recognizes dsDNA and creates cGAMP to activate STING-mediated type I IFN production. The activation of STING induces lupus disease in Fcgr2b deficient mice through the differentiation of dendritic cells. In contrast, Cgas-deficient mice could be generated more autoantibody production and proteinuria in pristane-induced lupus (PIL). These data suggested that the other dsDNA sensors could be involved in lupus development mechanisms.

Methods

This study aimed to identify the cGAS-mediated mechanisms contributing to lupus pathogenesis in PIL. The Cgas-deficient and WT mice were induced lupus disease with pristane and subsequently analyzed autoantibody, histopathology, and immunophenotypes. The lung tissues were analyzed with the expression profiles by RT-PCR and western blot. The bone marrow-derived macrophages were stimulated with inflammasome activators and observed pyroptosis.

Results

The Cgas-/- mice developed more severe pulmonary hemorrhage and autoantibody production than WT mice. The activated dendritic cells, IFN-g-, and IL-17a-producing T helper cells, and infiltrated macrophages in the lung were detected in Cgas-/- mice higher than in WT mice. We observed an increase in expression of Aim2, Casp11, and Ifi16 in the lung and serum IL-1a but IL-1b in pristane-injected Cgas-/- mice. The rise of Caspase-11 in the lung of pristane-injected Cgas-/- mice suggested noncanonical inflammasome activation. The activation of AIM2 and NLRP3 inflammasomes in bone marrow-derived macrophages (BMDMs) enhanced the number of dead cells in Cgas-/- mice compared with WT mice. Activation of the inflammasome significantly induced pyroptosis in Cgas-/- BMDMs. The dsDNA level, but not mitochondrial DNA, increased dramatically in pristane-injected Cgas-/- mice suggesting the dsDNA could be a ligand activating inflammasomes. The cGAS agonist-induced BMDM activation in the Cgas-/- mice indicated that the activation of DNA sensors other than cGAS enhanced activated macrophages.

Conclusion

These findings suggested that cGAS hampers the unusual noncanonical inflammasome activation through other DNA sensors.

Frontiers of Targeted Therapy and Predictors of Treatment Response in Systemic Sclerosis

Systemic sclerosis (scleroderma, SSc) is one of the most challenging rheumatic diseases, characterized by vasculopathy, dysregulation of the immune response, and progressive tissue fibrosis affecting the skin, lungs, heart, digestive tract, and kidneys [...].

Clinical case of olokizumab treatment in a patient with diffuse systemic sclerosis

Treatment algorithms for systemic sclerosis have not been completely developed. Effectivity of medications are usually used in clinical practice has a low level of evidence. Therefore, it is necessary to find a new treatment approaches for this nosological form. In the paper described clinical case of olokizumab treatment in a patient with diffuse systemic sclerosis with interstitial lung disease, polyserositis, severe microcirculatory alterations.

Autoantibodies as Biomarker and Therapeutic Target in Systemic Sclerosis

Systemic sclerosis (SSc) is a rare connective tissue disorder characterized by immune dysregulation evoking the pathophysiological triad of inflammation, fibrosis and vasculopathy. In SSc, several alterations in the B-cell compartment have been described, leading to polyclonal B-cell hyperreactivity, hypergammaglobulinemia and autoantibody production. Autoreactive B cells and autoantibodies promote and maintain pathologic mechanisms. In addition, autoantibodies in SSc are important biomarkers for predicting clinical phenotype and disease progression. Autoreactive B cells and autoantibodies represent potentially promising targets for therapeutic approaches including B-cell-targeting therapies, as well as strategies for unselective and selective removal of autoantibodies. In this review, we present mechanisms of the innate immune system leading to the generation of autoantibodies, alterations of the B-cell compartment in SSc, autoantibodies as biomarkers and autoantibody-mediated pathologies in SSc as well as potential therapeutic approaches to target these.

Interleukin-6 cytokine: An overview of the immune regulation, immune dysregulation, and therapeutic approach

Several studies have shown that interleukin 6 (IL-6) is a multifunctional cytokine with both pro-inflammatory and anti-inflammatory activity, depending on the immune response context. Macrophages are among several cells that secrete IL-6, which they express upon activation by antigens, subsequently inducing fever and production of acute-phase proteins from the liver. Moreover, IL-6 induces the final maturation of B cells into memory B cells and plasma cells as well as an adaptive role for short-term energy allocation. Activation of IL-6 receptors results in the intracellular activation of the JAK/STAT pathway with resultant production of inflammatory cytokines. Several mechanisms-controlled IL-6 expression, but aberrant production was shown to be crucial in the pathogenesis of many diseases, which include autoimmune and chronic inflammatory diseases. IL-6 in combination with transforming growth factor β (TGF-β) induced differentiation of naïve T cells to Th17 cells, which is the cornerstone in autoimmune diseases. Recently, IL-6 secretion was shown to form the backbone of hypercytokinemia seen in the Coronavirus disease 2019 (COVID-19)-associated hyperinflammation and multiorgan failure. There are two classes of approved IL-6 inhibitors: anti-IL-6 receptor monoclonal antibodies (e.g., tocilizumab) and anti-IL-6 monoclonal antibodies (i.e., siltuximab). These drugs have been evaluated in patients with rheumatoid arthritis, juvenile idiopathic arthritis, cytokine release syndrome, and COVID-19 who have systemic inflammation. JAK/STAT pathway blockers were also successfully used in dampening IL-6 signal transduction. A better understanding of different mechanisms that modulate IL-6 expression will provide the much-needed solution with excellent safety and efficacy profiles for the treatment of autoimmune and inflammatory diseases in which IL-6 derives their pathogenesis.