Novel treatment approaches to fibrosis in scleroderma.
ABSTRACT The molecular mechanisms leading to tissue fibrosis were only poorly understood in the past, and even today the cause or trigger of systemic sclerosis is still unknown. Remarkable breakthrough findings have been obtained regarding the identification of key molecules, key cellular mechanisms, and key intracellular signaling cascades, which mediate the perpetuation of fibrosis rather than trigger it. These findings have true translational implications, because modifiers of these key mediators and key mechanisms are often in clinical use in other disease indications, such as cancer. This article summarizes the clinical and preclinical evidence of examples of these novel antifibrotic treatment approaches in systemic sclerosis, including stem cell transplantation, modifiers of transforming growth factor-beta1 signaling, intravenous immunoglobulins, tyrosine kinase inhibitors, and histone deacetylase inhibitors.
Article: Sklerodermie[Show abstract] [Hide abstract]
ABSTRACT: Die Sklerodermie (Synonyme: systemische Sklerose, systemische Sklerodermie) ist eine Systemerkrankung, die neben der Haut auch innere Organe wie die Lunge, den Gastrointestinaltrakt, die Niere und das Herz befällt. Pathogenetisch ist zwischen einer unkontrollierten Bindegewebsvermehrung (Fibrose) und einer Vaskulopathie zu unterscheiden. Dies führt klinisch neben den Organfibrosen auch zu Gefäßmanifestationen. Hierzu zählen Fingerkuppenulzera, die pulmonalarterielle Hypertonie und die akute Nierenkrise. Von der systemischen Sklerose sind lokalisierte Sklerodermieformen wie die Morphea abzugrenzen, die ohne Organkomplikationen verlaufen. Aufgrund ihrer klinischen Heterogenität, ihrer hohen Morbidität und Mortalität stellt die systemischen Sklerose für den klinischen Alltag eine große diagnostische und therapeutische Herausforderung dar. Dieser Übersichtsartikel fasst den aktuellen Stand zur Klassifikation und Epidemiologie, Pathogenese, den wichtigsten klinischen Manifestationen wie interstitielle Fibrose, pulmonalarterielle Hypertonie, akute Nierenkrise und periphere Vaskulopathie zusammen und gibt einen Überblick aktueller und zukünftiger Therapiemöglichkeiten. Scleroderma (synonyms: systemic sclerosis, systemic scleroderma) is a systemic disease which affects the skin as well as internal organs such as the lungs, gastrointestinal tract, kidneys, and the heart. Pathogenetically a distinction should be made between uncontrolled formation of extracellular matrix proteins (fibrosis) and vasculopathy. In addition to organ fibrosis, this leads to a clinical picture of vascular manifestations. These include fingertip ulcers, pulmonary arterial hypertension, and acute renal crisis. Localized forms of scleroderma, such as morphea, which do not involve organ complications, should be differentiated from systemic sclerosis. Due to its clinical heterogeneity and high rate of morbidity and mortality, systemic sclerosis poses an enormous diagnostic and therapeutic challenge in everyday clinical practice. This review article summarizes the current status of classification and epidemiology, pathogenesis, and the most important clinical manifestations such as interstitial fibrosis, pulmonary arterial hypertension, acute renal crisis, and peripheral vasculopathy and provides an overview of current and future treatment options. SchlüsselwörterSklerodermie-Systemische Sklerose-Fibrosierende Erkrankungen-Lungenfibrose-Pulmonalarterielle Hypertonie KeywordsScleroderma-Systemic sclerosis-Fibrotic diseases-Pulmonary fibrosis-Pulmonary arterial hypertensionDer Internist 01/2010; 51(1):30-38. · 0.27 Impact Factor
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ABSTRACT: BACKGROUND: Skin fibrotic disorders such as systemic sclerosis (SSc) are characterized by an excessive accumulation of extracellular matrix (ECM), and develop under the influence of certain cytokines. We previously established a mouse model of skin fibrosis induced by exogenous application of cytokines. We have revealed that both the number of macrophages and the levels of macrophage chemoattractant protein-1 (MCP-1) mRNA positively correlate with the extent of skin fibrosis. Macrophages can be divided into two subsets, the first expressing CCR2, and the second expressing CX3CR1. OBJECTIVE: To elucidate the role of skin infiltrating macrophages based on CCR2 and CX3CR1 in this cytokine-induced murine fibrosis model. METHODS: We examined the amounts of collagen deposited in granulation tissues, the numbers of macrophages and the levels of several mRNA in wild type (WT) mice, CCR2(-/-) mice, and CX3CR1(-/-) mice during injections of transforming growth factor-β (TGF-β) followed by injections of connective tissue growth factor (CTGF). RESULTS: TGF-β injection increased the expressions of MCP-1, fractalkine, CCR2 and CX3CR1 mRNA in WT mice. The overproduction of collagen induced by TGF-β was significantly reduced by CCR2 deficiency, while collagen contents induced by CTGF were restored to wild-type levels. In contrast, overproduction of collagen in CX3CR1-deficient mice decreased nearly 50% by both TGF-β and CTGF stimulations. CONCLUSION: The involvement of CCR2/MCP-1 interaction (CCR2-dependent loop) was during the TGF-β phase. In contrast, the fractalkine/CX3CR1 interaction contributes to the initiation of fibrosis by TGF-β and its maintenance by CTGF. Collectively, two subsets of macrophages both cooperatively and independently play important roles in the development of fibrosis.Journal of dermatological science 10/2012; · 3.71 Impact Factor
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ABSTRACT: Fibrosis in multiple organs is a prominent pathological finding and distinguishing hallmark of systemic sclerosis (SSc). Findings during the past 5 years have contributed to a more complete understanding of the complex cellular and molecular underpinning of fibrosis in SSc. Fibroblasts, the principal effector cells, are activated in the profibrotic cellular milieu by cytokines and growth factors, developmental pathways, endothelin 1 and thrombin. Innate immune signaling via Toll-like receptors, matrix-generated biomechanical stress signaling via integrins, hypoxia and oxidative stress seem to be implicated in perpetuating the process. Beyond chronic fibroblast activation, fibrosis represents a failure to terminate tissue repair, coupled with an expanded population of mesenchymal cells originating from bone marrow and transdifferentiation of epithelial cells, endothelial cells and pericytes. In addition, studies have identified intrinsic alterations in SSc fibroblasts resulting from epigenetic changes, as well as altered microRNA expression that might underlie the cell-autonomous, persistent activation phenotype of these cells. Precise characterization of the deregulated extracellular and intracellular signaling pathways, mediators and cellular differentiation programs that contribute to fibrosis in SSc will facilitate the development of selective, targeted therapeutic strategies. Effective antifibrotic therapy will ultimately involve novel compounds and repurposing of drugs that are already approved for other indications.Nature Reviews Rheumatology 01/2012; 8(1):42-54. · 9.75 Impact Factor