The relationship between skin symptoms and the scleroderma modification of the health assessment questionnaire, the modified Rodnan skin score, and skin pathology in patients with systemic sclerosis

Effects of upadacitinib and PD29 on oxidative damage and inflammation in bleomycin-induced scleroderma model kidney tissues

Objective: Scleroderma (SSc) is a rare autoimmune tissue disease. There is currently no effective treatment for SSc. The aim of this study was to investigate the antioxidant and anti-inflammatory effects of upadacitinib and PD29 on total oxidant status (TOS), total antioxidant status (TAS), malondialdehyde (MDA), catalase (CAT), glutathione (GSH) peroxidase levels, and interleukin-6 (IL-6) and interleukin-13 ( IL-13) in kidney tissues of an experimental SSc model. Materials and Methods: The experimental design was established with five groups of eight mice: Control, bleomycin (BLM) (5 μg/kg), BLM + upadacitinib (3mg/kg), BLM + PD29 (5 mg/kg) and BLM + PD29 + upadacitinib group. BLM was administered subcutaneously once a day for 21 days. PD29 was administered subcutaneously and upadacitinib (gavage) were injected for 21 days. Renal tissues were collected at the end of the experiment. Renal TOS, TAS, MDA, CAT, GSH levels, and IL-6 and IL-13 gene expressions were evaluated. Results: Upadacitinib and PD29 affected oxidant status and TOS. MDA levels decreased, and GSH, CAT, and TAS levels increased. Also, upadacitinib and PD29 decreased inflammation via IL-6 and IL-13 cytokines. Conclusion: Upadacitinib and PD29 may have therapeutic roles for SSc renal crisis.

Systems-based identification of the Hippo pathway for promoting fibrotic mesenchymal differentiation in systemic sclerosis

Systemic sclerosis (SSc) is a devastating autoimmune disease characterized by excessive production and accumulation of extracellular matrix, leading to fibrosis of skin and other internal organs. However, the main cellular participants in SSc skin fibrosis remain incompletely understood. Here using differentiation trajectories at a single cell level, we demonstrate a dual source of extracellular matrix deposition in SSc skin from both myofibroblasts and endothelial-to-mesenchymal-transitioning cells (EndoMT). We further define a central role of Hippo pathway effectors in differentiation and homeostasis of myofibroblast and EndoMT, respectively, and show that myofibroblasts and EndoMTs function as central communication hubs that drive key pro-fibrotic signaling pathways in SSc. Together, our data help characterize myofibroblast differentiation and EndoMT phenotypes in SSc skin, and hint that modulation of the Hippo pathway may contribute in reversing the pro-fibrotic phenotypes in myofibroblasts and EndoMTs.

Understanding Fibroblast Heterogeneity in Form and Function

Historically believed to be a homogeneous cell type that is often overlooked, fibroblasts are more and more understood to be heterogeneous in nature. Though the mechanisms behind how fibroblasts participate in homeostasis and pathology are just beginning to be understood, these cells are believed to be highly dynamic and play key roles in fibrosis and remodeling. Focusing primarily on fibroblasts within the skin and during wound healing, we describe the field's current understanding of fibroblast heterogeneity in form and function. From differences due to embryonic origins to anatomical variations, we explore the diverse contributions that fibroblasts have in fibrosis and plasticity. Following this, we describe molecular techniques used in the field to provide deeper insights into subpopulations of fibroblasts and their varied roles in complex processes such as wound healing. Limitations to current work are also discussed, with a focus on future directions that investigators are recommended to take in order to gain a deeper understanding of fibroblast biology and to develop potential targets for translational applications in a clinical setting.

Extensive and Persistent Extravascular Dermal Fibrin Deposition Characterizes Systemic Sclerosis

Systemic sclerosis (SSc) is an autoimmune disease characterized by progressive multiorgan fibrosis. While the cause of SSc remains unknown, a perturbed vasculature is considered a critical early step in the pathogenesis. Using fibrinogen as a marker of vascular leakage, we found extensive extravascular fibrinogen deposition in the dermis of both limited and diffuse systemic sclerosis disease, and it was present in both early and late-stage patients. Based on a timed series of excision wounds, retention on the fibrin deposit of the splice variant domain, fibrinogen αEC, indicated a recent event, while fibrin networks lacking the αEC domain were older. Application of this timing tool to SSc revealed considerable heterogeneity in αEC domain distribution providing unique insight into disease activity. Intriguingly, the fibrinogen-αEC domain also accumulated in macrophages. These observations indicate that systemic sclerosis is characterized by ongoing vascular leakage resulting in extensive interstitial fibrin deposition that is either continually replenished and/or there is impaired fibrin clearance. Unresolved fibrin deposition might then incite chronic tissue remodeling.

Assessment of disease outcome measures in systemic sclerosis

The assessment of disease activity in systemic sclerosis (SSc) is challenging owing to its heterogeneous manifestations across multiple organ systems, the variable rate of disease progression and regression, and the relative paucity of patients in early-phase therapeutic trials. Despite some recent successes, most clinical trials have failed to show efficacy, underscoring the need for improved outcome measures linked directly to disease pathogenesis, particularly applicable for biomarker studies focused on skin disease. Current outcome measures in SSc-associated interstitial lung disease and SSc skin disease are largely adequate, although advancing imaging technology and the incorporation of skin mRNA biomarkers might provide opportunities for earlier detection of the therapeutic effect. Biomarkers can further inform pathogenesis, enabling early phase trials to act as reverse translational studies through the incorporation of routine high-throughput sequencing.

Emerging Role of Dipeptidyl Peptidase-4 in Autoimmune Disease

Dipeptidyl-peptidase IV (DPP4), originally identified as an aminopeptidase in 1960s, is an ubiquitously expressed protease presented as either a membrane-bound or soluble form. DPP4 cleaves dipeptide off from the N-terminal of its substrates, altering the bioactivity of its substrates. Subsequent studies reveal that DPP4 is also involved in various cellular processes by directly binding to a number of ligands, including adenosine deaminase, CD45, fibronectin, plasminogen, and caveolin-1. In recent years, many novel functions of DPP4, such as promoting fibrosis and mediating virus entry, have been discovered. Due to its implication in fibrotic response and immunoregulation, increasing studies are focusing on the potential role of DPP4 in inflammatory disorders. As a moonlighting protein, DPP4 possesses multiple functions in different types of cells, including both enzymatic and non-enzymatic functions. However, most of the review articles on the role of DPP4 in autoimmune disease were focused on the association between DPP4 enzymatic inhibitors and the risk of autoimmune disease. An updated comprehensive summary of DPP4’s immunoregulatory actions including both enzymatic dependent and independent functions is needed. In this article, we will review the recent advances of DPP4 in immune regulation and autoimmune rheumatic disease.

Single Cell RNA Sequencing in Autoimmune Inflammatory Rheumatic Diseases: Current Applications, Challenges and a Step Toward Precision Medicine

Single cell RNA sequencing (scRNA-seq) represents a new large scale and high throughput technique allowing analysis of the whole transcriptome at the resolution of an individual cell. It has emerged as an imperative method in life science research, uncovering complex cellular networks and providing indices that will eventually lead to the development of more targeted and personalized therapies. The importance of scRNA-seq has been particularly highlighted through the analysis of complex biological systems, in which cellular heterogeneity is a key aspect, such as the immune system. Autoimmune inflammatory rheumatic diseases represent a group of disorders, associated with a dysregulated immune system and high patient heterogeneity in both pathophysiological and clinical aspects. This complicates the complete understanding of underlying pathological mechanisms, associated with limited therapeutic options available and their long-term inefficiency and even toxicity. There is an unmet need to investigate, in depth, the cellular and molecular mechanisms driving the pathogenesis of rheumatic diseases and drug resistance, identify novel therapeutic targets, as well as make a step forward in using stratified and informed therapeutic decisions, which could now be achieved with the use of single cell approaches. This review summarizes the current use of scRNA-seq in studying different rheumatic diseases, based on recent findings from published in vitro, in vivo, and clinical studies, as well as discusses the potential implementation of scRNA-seq in the development of precision medicine in rheumatology.

Myofibroblast transcriptome indicates SFRP2hi fibroblast progenitors in systemic sclerosis skin

Skin and lung fibrosis in systemic sclerosis (SSc) is driven by myofibroblasts, alpha-smooth muscle actin expressing cells. The number of myofibroblasts in SSc skin correlates with the modified Rodnan skin score, the most widely used clinical measure of skin disease severity. Murine fibrosis models indicate that myofibroblasts can arise from a variety of different cell types, but their origin in SSc skin has remained uncertain. Utilizing single cell RNA-sequencing, we define different dermal fibroblast populations and transcriptome changes, comparing SSc to healthy dermal fibroblasts. Here, we show that SSc dermal myofibroblasts arise in two steps from an SFRP2^hi/DPP4-expressing progenitor fibroblast population. In the first step, SSc fibroblasts show globally upregulated expression of transcriptome markers, such as PRSS23 and THBS1. A subset of these cells shows markers indicating that they are proliferating. Only a fraction of SFRP2^hi SSc fibroblasts differentiate into myofibroblasts, as shown by expression of additional markers, SFRP4 and FNDC1. Bioinformatics analysis of the SSc fibroblast transcriptomes implicated upstream transcription factors, including FOSL2, RUNX1, STAT1, FOXP1, IRF7 and CREB3L1, as well as SMAD3, driving SSc myofibroblast differentiation.

Myofibroblasts drive fibrosis in systemic sclerosis (SSc), but the cellular progenitors are unknown. Utilizing single cell RNA-sequencing, the authors show that SSc dermal myofibroblasts arise in a two-step process from SFRP2/DPP4-expressing progenitors and implicate upstream transcription factors.

The Role of Pro-fibrotic Myofibroblasts in Systemic Sclerosis: from Origin to Therapeutic Targeting

Systemic sclerosis (SSc, scleroderma) is a complex connective tissue disorder characterized by multisystem clinical manifestations resulting from immune dysregulation/autoimmunity, vasculopathy and, most notably, progressive fibrosis of the skin and internal organs. In recent years, it has emerged that the main drivers of SSc-related tissue fibrosis are myofibroblasts, a type of mesenchymal cells with both the extracellular matrix-synthesizing features of fibroblasts and the cytoskeletal characteristics of contractile smooth muscle cells. The accumulation and persistent activation of pro-fibrotic myofibroblasts during SSc development and progression result into elevated mechanical stress and reduced matrix plasticity within the affected tissues and may be ascribed to a reduced susceptibility of these cells to pro-apoptotic stimuli, as well as their increased formation from tissue-resident fibroblasts or transition from different cell types. Given the crucial role of myofibroblasts in SSc pathogenesis, finding the way to inhibit myofibroblast differentiation and accumulation by targeting their formation, function and survival may represent an effective approach to hamper the fibrotic process or even halt or reverse established fibrosis. In this review, we discuss the role of myofibroblasts in SSc-related fibrosis, with a special focus on their cellular origin and the signaling pathways implicated in their formation and persistent activation. Furthermore, we provide an overview of potential therapeutic strategies targeting myofibroblasts that may be able to counteract fibrosis in this pathological condition.

How to perform high ultrasound examination of skin involvement among patients with systemic sclerosis - proposition of a unified protocol

Introduction

A fast and cheap method of skin assessment in systemic sclerosis (SSc) is an area of extensive research. Established in 1979, the Rodnan skin score is a palpation-based method used among clinicians. This method has some limitations, such as: examiner’s skills, subjective results, and no standardization. In the last few years researchers have been exploring ultrasound-based techniques as a possible tool for skin assessment among patients with SSc. The aim of the study is to develop a protocol of elastography-based skin imaging evaluation among patients with SSc.

Material and methods

Review of the literature and own experience.

Results

Proposition of elastography-based skin imaging protocol among patients with SSc.

Conclusions

The authors present a potential protocol of ultrasound-based examination of skin involvement among patients with SSc.

Can Patient-Reported Symptoms Be Used to Measure Disease Activity in Systemic Sclerosis?

OBJECTIVE

To evaluate the association between patient-reported symptoms and changes in disease activity over time in systemic sclerosis (SSc).

METHODS

Using data from 1,636 patients enrolled in the Australian Scleroderma Cohort Study, we used generalized estimating equations to determine the relationship between patient-reported worsening of Raynaud's phenomenon (RP), skin involvement, and breathlessness in the month preceding each study visit and features of disease activity in the corresponding organ systems. The associations between the following parameters were analyzed: patient-reported worsening RP and the presence of new-onset digital pitting and digital ulcers; patient-reported worsening skin involvement and increasing modified Rodnan skin thickness score (MRSS); new areas of skin involvement and new-onset joint contractures; patient-reported worsening breathlessness and deteriorating respiratory functions test (RFT) results, indicated by a 10% decrease in forced vital capacity (FVC) and a 15% decrease in diffusing capacity for carbon monoxide (DLco), new-onset interstitial lung disease (ILD), and new-onset pulmonary arterial hypertension (PAH).

RESULTS

We found a significant association between patient-reported worsening RP and the presence of digital ulcers (odds ratio [OR] 1.53 [95% confidence interval (95% CI) 0.60-0.93]), patient-reported worsening skin involvement and increasing MRSS (OR 2.10 [95% CI 1.54-2.86]), and worsening patient breathlessness and deteriorating RFTs (FVC OR 2.12 [95% CI 1.70-2.65]; DLco OR 1.97 [95% CI 1.34-2.02]), new-onset ILD (OR 1.91 [95% CI 1.40-2.61]), and new-onset PAH (OR 5.08 [95% CI 3.59-7.19]).

CONCLUSION

These results demonstrate that patient-reported symptoms are associated with clinically meaningful changes in disease activity in patients with SSc. This suggests that when objective measures of change in disease status are unavailable, patient-reported symptoms could be used to indicate a change in SSc disease activity.

Skin Histology in Systemic Sclerosis: a Relevant Clinical Biomarker

PURPOSE OF REVIEW

Systemic sclerosis (SSc) is a life-threatening autoimmune disease that causes debilitating skin fibrosis. The skin in SSc is easily accessible, and skin biopsies may provide rich biological data regarding underlying disease pathophysiology. Here, we review literature relevant to the potential for skin histology to serve as a diagnostic, pharmacokinetic/response, and predictive biomarker in SSc.

RECENT FINDINGS

Multiple histologic parameters correlate with SSc severity, including alpha smooth muscle actin (aSMA), CD34, collagen density, thickness, and inflammatory cell infiltration. Recent clinical trials incorporate skin histology as exploratory outcome measurements; however, a standard approach is not yet established. The possibility that skin histology may be useful as a predictive biomarker was suggested by a recent study that identified genes related to skin aSMA and CD34 staining intensity that were increased at baseline among improvers versus nonimprovers. Current literature supports skin histology as a mechanism to measure treatment response, but future work is needed to define minimally meaningful changes in key SSc skin histologic features.

The contribution of mesenchymal transitions to the pathogenesis of systemic sclerosis

Systemic sclerosis (SSc) is a multifaceted connective tissue disease characterized by widespread vasculopathy and autoimmune reactions that evolve into progressive interstitial, perivascular, and vessel wall fibrosis that affects the skin and multiple internal organs. Such an uncontrolled fibrotic process gradually disrupts the physiologic architecture of the affected tissues and frequently leads to significant organ dysfunction, thus representing a major cause of death in SSc patients. The main fibrosis orchestrators in SSc are represented by chronically activated myofibroblasts, a peculiar population of mesenchymal cells combining the extracellular matrix-synthesizing features of fibroblasts with cytoskeletal characteristics of contractile smooth muscle cells. Multiple lines of evidence support the notion that profibrotic myofibroblasts may derive not only from the activation of tissue resident fibroblasts but also from a variety of additional cell types, including pericytes, epithelial cells, vascular endothelial cells and preadipocytes/adipocytes. Here we overview an emerging picture that espouses that several cell transitional processes may be novel essential contributors to the pool of profibrotic myofibroblasts in SSc, potentially representing new suitable targets for therapeutic purposes. An in-depth dissection of the multiple origins of myofibroblasts and the underlying molecular mechanisms may be crucial in the process of deciphering the cellular bases of fibrosis persistence and refractoriness to the treatment and, therefore, may help in developing more effective and personalized therapeutic opportunities for SSc patients.

Durometry as an alternative tool to the modified Rodnan's skin score in the assessment of diffuse systemic sclerosis patients: a cross-sectional study

BACKGROUND

The reproducibility and reliability of the modified Rodnan's Skin Score (mRSS) are debated due to investigator-related subjectivity. Here, we evaluate if durometry correlates with mRSS in patients with diffuse systemic sclerosis (SSc).

METHODS

This cross-sectional study was conducted from December 2018 to June 2019, including 58 diffuse SSc patients. Two certified researchers, blind to each other's scores, performed the mRSS, followed by durometry at 17 predefined skin sites. For durometry and mRSS, individual scores per skin site were registered. Durometry and mRSS results measured by each researcher, as well as scores from different researchers, were compared. Skin thickness measurements from forearm skin biopsies were available in a subset of the patients, for comparisons. Statistical analyses included Cohen's Kappa Coefficient, Intraclass Correlation Coefficient, Kendall's Coefficient and Spearman's test.

RESULTS

Mean (standard deviation, SD) patient age was 44.8 (12.9) years, and 88% were female. Inter-rater agreement varied from 0.88 to 0.99 (Intraclass correlation coefficient) for durometry, and 0.54 to 0.79 (Cohen's Kappa coefficient) for mRSS, according to the specific evaluated sites. When data were compared with skin thickness assessed in forearm biopsies, durometry correlated better with skin thickness than mRSS.

CONCLUSION

Durometry may be considered as an alternative method to quantify skin involvement in patients with diffuse SSc. The strong inter-rater agreement suggests that the method may be useful for the assessment of patients by multiple researchers, as in clinical trials.

Patient-reported outcome instruments in clinical trials of systemic sclerosis

Patient-reported outcome instruments provide valuable insight into disease-related morbidity known only to the patient and complement more objective outcome tools in the clinical trial setting. They are of particular importance in systemic sclerosis owing to the challenges around defining disease activity, the episodic nature of many disease-specific manifestations and the paucity of validated objective surrogate outcome measures for use in clinical trials. Early clinical trials of systemic sclerosis often incorporated legacy patient-reported outcome instruments, but the last 20 years has witnessed the emergence of several scleroderma-specific instruments that are now being routinely used alongside other outcomes in systemic sclerosis clinical trials. More recently, the value of patient-reported outcomes has been highlighted by their prominence in the American College of Rheumatology Combined Response Index for Systemic Sclerosis that has been utilized as the primary endpoint of recent clinical trials of early diffuse systemic sclerosis. This review considers the role and performance of the various patient-reported outcome instruments utilized in systemic sclerosis clinical trials, the current positioning of patient-reported outcome instruments within clinical trial endpoint models across the range of systemic sclerosis disease manifestations and, where applicable, we shall highlight areas for future research.

A patient-centered approach to the burden of symptoms in patients with scleroderma treated with Bosentan: A prospective single-center observational study

Systemic sclerosis (SSc) is a rare and complex autoimmune disease associated with poor vital and functional outcomes. The functional hindrance in patients derives from various disease-specific manifestations, including Raynaud's phenomenon and digital ulcers (DUs). Bosentan is an endothelin receptor antagonist capable of preventing the appearance of new DUs in patients with scleroderma. The present study aimed to evaluate the effects of Bosentan on the severity of Raynaud's phenomenon, DU-related symptoms and functional impairment during the first year of treatment. A prospective study that included adult patients with SSc admitted to the Rheumatology Department between January 2016 and January 2017 that were candidates for Bosentan therapy, was performed. All patients were asked to evaluate the burden of symptoms secondary to Raynaud's and DUs using a visual analogue scale (VAS), whereas functional hindrance was assessed via Health Assessment Questionnaire Disability Index (HAQ-DI). The outcomes were assessed at baseline and every 3 months during 1 year of therapy. Among the 41 patients included initially, 2 participants discontinued the treatment after 1 month due to adverse events (elevation of liver enzymes). The study cohort exhibited a significant improvement in HAQ-DI, VAS-R and VAS-DU scores in response to Bosentan therapy over the 1-year follow-up period. Higher scores at baseline predicted a weaker treatment-related improvement, with the risk of a poor outcome being increased by 220% for VAS-R, 116% for VAS-DU, whereas no increase was observed for HAQ-DI. The post-treatment improvement in VAS-DU levels was associated with a better outcome for HAQ-DI (R=0.44; P=0.005). This association was not identified for VAS-R (R=0.24; P=0.137). Throughout the follow-up period, patients with dyspnea presented with significantly higher HAQ-DI scores compared with non-dyspneic patients. Bosentan therapy may indirectly influence functionality and quality of life in patients with scleroderma by reducing the burden of Raynaud's and DU-related symptoms. Nonetheless, patients with SSc with a decreased symptom burden at baseline exhibited improved outcomes.

Existing and novel biomarkers for precision medicine in systemic sclerosis

The discovery and validation of biomarkers resulting from technological advances in the analysis of genomic, transcriptomic, lipidomic and metabolomic pathways involved in the pathogenesis of complex human diseases have led to the development of personalized and rationally designed approaches for the clinical management of such disorders. Although some of these approaches have been applied to systemic sclerosis (SSc), an unmet need remains for validated, non-invasive biomarkers to aid in the diagnosis of SSc, as well as in the assessment of disease progression and response to therapeutic interventions. Advances in global transcriptomic technology over the past 15 years have enabled the assessment of microRNAs that circulate in the blood of patients and the analysis of the macromolecular content of a diverse group of lipid bilayer membrane-enclosed extracellular vesicles, such as exosomes and other microvesicles, which are released by all cells into the extracellular space and circulation. Such advances have provided new opportunities for the discovery of biomarkers in SSc that could potentially be used to improve the design and evaluation of clinical trials and that will undoubtedly enable the development of personalized and individualized medicine for patients with SSc.

Gastrointestinal manifestations on impaired quality of life in systemic sclerosis

OBJECTIVE

To analyze the impact of gastrointestinal manifestations on quality of life in patients with systemic sclerosis (SSc) and to provide clinical evidence for their early treatment and health-related management.

METHODS

Altogether 65 patients admitted to the Peking Union Medical College Hospital selected from a disease cohort and 127 matched controls were enrolled. A self-assessment questionnaire was completed by all participants. Each participant completed scleroderma gastrointestinal tract 1.0 (SSC-GIT 1.0) questionnaire (including reflux or indigestion, diarrhea, constipation, distention, emotional well-being, and social functioning). Autoimmune antibodies were tested in SSc patients.

RESULTS

Among these SSc cases, gastrointestinal manifestations were seen in 84.6%. Reflux/indigestion and diarrhea were more common in SSc patients than in the control group (67.7% vs 27.8%; 27.7% vs 10.2%, P < 0.05). SSc patients had a significantly higher percentage of abnormal social functioning than the control group (33.8% vs 3.9%, P < 0.05). SSc patients with abnormal social functioning and abnormal emotional well-being had worse distention, diarrhea, and constipation statuses. Patients with reflux or indigestion and diarrhea had lower anti-Scl-70 level than those without (both P < 0.05). Patients with distention had higher levels of anti-RNP and anti-SSA than those without distention (both P < 0.05). Patients with diarrhea had higher levels of anti-RNP than those without diarrhea (P = 0.014).

CONCLUSIONS

Gastrointestinal involvement is frequent in SSc, with reflux or indigestion as the most common symptom. The impaired quality of life in patients with SSc indicates that early and active management should be considered.

Unraveling SSc Pathophysiology; The Myofibroblast

Systemic sclerosis (SSc) is a severe auto-immune disease, characterized by vasculopathy and fibrosis of connective tissues. SSc has a high morbidity and mortality and unfortunately no disease modifying therapy is currently available. A key cell in the pathophysiology of SSc is the myofibroblast. Myofibroblasts are fibroblasts with contractile properties that produce a large amount of pro-fibrotic extracellular matrix molecules such as collagen type I. In this narrative review we will discuss the presence, formation, and role of myofibroblasts in SSc, and how these processes are stimulated and mediated by cells of the (innate) immune system such as mast cells and T helper 2 lymphocytes. Furthermore, current novel therapeutic approaches to target myofibroblasts will be highlighted for future perspective.

The Nrf2-Antioxidant Response Element Signaling Pathway Controls Fibrosis and Autoimmunity in Scleroderma

Systemic sclerosis (SSc) is an autoimmune disease with fibrosis of the skin and internal organs and vascular alterations. Dysregulations in the oxidant/antioxidant balance are known to be a major factor in the pathogenesis of the disease. Indeed, reactive oxygen species (ROS) trigger neoepitopes leading to a breach of immune tolerance and autoimmune responses, activate fibroblasts to proliferate and to produce excess of type I collagen. ROS also alter endothelial cells leading to vascular dysfunction. Glutathione (GSH) is the most potent antioxidant system in eukaryotic cells. Numerous studies have reported a defect in GSH in SSc animal models and humans, but the origin of this defect remains unknown. The transcription factor NRF2 is a key player in the antioxidant defense, as it can induce the transcription of antioxidant and cytoprotective genes, including GSH, through its interaction with the antioxidant response elements. In this work, we investigated whether NRF2 could be implicated in the pathogenesis of SSc, and if this pathway could represent a new therapeutic target in this orphan disease with no curative medicine. Skin biopsies from 11 patients and 10 controls were harvested, and skin fibroblasts were extracted. Experimental SSc was induced both in BALB/c and in nrf2^-/- mice by daily intradermal injections of hypochloric acid. In addition, diseased BALB/c mice were treated with an nrf2 agonist, dimethyl fumarate, or placebo. A drop in nrf2 and target genes mRNA levels was observed in skin fibroblasts of SSc patients compared to controls. Moreover, the nrf2 pathway is also downregulated in skins and lungs of SSc mice. In addition, we observed that nrf2^-/- mice have a more severe form of SSc with increased fibrosis and inflammation compared to wild-type SSc mice. Diseased mice treated with the nrf2 agonist dimethyl fumarate (DMF) exhibited reduced fibrosis and immune activation compared to untreated mice. The ex vivo treatment of skin fibroblasts from SSc mice with DMF restores GSH intracellular content, decreases ROS production and cell proliferation. These results suggest that the nrf2 pathway is highly dysregulated in human and SSc mice with deleterious consequences on fibrosis and inflammation and that Nrf2 modulation represents a therapeutic target in SSc.

Cutaneous Manifestations of Scleroderma and Scleroderma-Like Disorders: a Comprehensive Review

Scleroderma refers to an autoimmune connective tissue fibrosing disease, including three different subsets: localized scleroderma, limited cutaneous systemic sclerosis, and diffuse cutaneous systemic sclerosis with divergent patterns of organ involvement, autoantibody profiles, management, and prognostic implications. Although systemic sclerosis is considered the disease prototype that causes cutaneous sclerosis, there are many other conditions that can mimic and be confused with SSc. They can be classified into immune-mediated/inflammatory, immune-mediated/inflammatory with abnormal deposit (mucinoses), genetic, drug-induced and toxic, metabolic, panniculitis/vascular, and (para)neoplastic disorders according to clinico-pathological and pathogenetic correlations. This article reviews the clinical presentation with emphasis on cutaneous disease, etiopathogenesis, diagnosis, and treatment options available for the different forms of scleroderma firstly and for scleroderma-like disorders, including scleromyxedema, scleredema, nephrogenic systemic fibrosis, eosinophilic fasciitis, chronic graft-versus-host disease, porphyria cutanea tarda, diabetic stiff-hand syndrome (diabetic cheiroartropathy), and other minor forms. This latter group of conditions, termed also scleroderma mimics, sclerodermiform diseases, or pseudosclerodermas, shares the common thread of skin thickening but presents with distinct cutaneous manifestations, skin histology, and systemic implications or disease associations, differentiating each entity from the others and from scleroderma. The lack of Raynaud's phenomenon, capillaroscopic abnormalities, or scleroderma-specific autoantibodies is also important diagnostic clues. As cutaneous involvement is the earliest, most frequent and characteristic manifestation of scleroderma and sclerodermoid disorders, dermatologists are often the first-line doctors who must be able to promptly recognize skin symptoms to provide the affected patient a correct diagnosis and appropriate management.

Chronic Multiorgan Rare Disease: The Role of the Nurse Practitioner as a Leader of the Healthcare Team

Value in healthcare must focus on accessibility, quality, and affordability. This article describes how a healthcare team provides value by meeting the needs of a rare disease patient and underscores the importance of a chronic multiorgan rare disease home. A nurse practitioner can ensure that barriers to evaluation are removed and communication is prioritized in order to provide accessible and affordable care to a patient with rare disease without jeopardizing quality of care.