Vaskul�re Ver�nderungen in der Pathogenese der systemischen Sklerose

Tanshinone IIA attenuates interleukin-17A-induced systemic sclerosis patient-derived dermal vascular smooth muscle cell activation via inhibition of the extracellular signal-regulated kinase signaling pathway

OBJECTIVE

Salvia miltiorrhiza has long been used to treat systemic sclerosis. Tanshinone IIA, one of the phytochemicals derived from the roots of Salvia miltiorrhiza, exhibits multiple biological activities. The present study aimed to investigate whether tanshinone IIA has an effect on the interleukin-17A-induced functional activation of systemic sclerosis patient-derived dermal vascular smooth muscle cells.

METHODS

Systemic sclerosis patient-derived dermal vascular smooth muscle cells were incubated with various dosages of tanshinone IIA in the presence of interleukin-17A or the serum of systemic sclerosis patients. Cell proliferation was assessed using Cell Counting Kit-8. The expression of collagen 1 and 3 in cells was evaluated by immunofluorescence. Cell migration was measured using a transwell assay. The expression of phospho-extracellular signal-regulated kinase was detected by Western blotting.

RESULTS

Our data demonstrate that tanshinone IIA exerts an inhibitory effect on interleukin-17A-induced systemic sclerosis patient-derived dermal vascular smooth muscle cell proliferation, collagen synthesis and migration.

CONCLUSION

These findings suggest that tanshinone IIA might serve as a promising therapeutic agent for the treatment of systemic sclerosis.

Care of patients with scleroderma in the intensive care setting

Scleroderma or systemic sclerosis (SSc) is a connective tissue disease (CTD) associated with fibrosing and vascular complications involving multiple organs. The care of these patients in the critical care setting is frequently challenging due to multiple complications and refractory organ involvement. However, awareness of specific organ involvement associated with scleroderma can allow many complications to be anticipated and effectively treated. Cardiac involvement can lead to arrhythmias and heart failure, whereas pulmonary involvement can be associated with pulmonary arterial hypertension, fibrosis, or both. Renal vascular disease and scleroderma renal crisis (SRC), once a uniformly fatal complication, is particularly important to recognize early, as it can be treated successfully. Gastrointestinal involvement can lead to bleeding, aspiration, obstruction, and malabsorption. Severe Raynaud may lead to digital ischemia and gangrene. Therapies must target involved organ system or organ systems. Corticosteroids, a mainstay for related CTDs, do not typically provide any benefit and may cause harm. Vasodilators can effectively treat vascular complications but must target the appropriate vascular bed. Proactive utilization of proton pump inhibitors, recognition of bleeding from gastrointestinal vascular ectasia, and nutritional support can considerably ameliorate gastrointestinal morbidities. Effective treatment of fibrotic complications remains elusive and is the current frontier for scleroderma therapeutics.

Mechanisms of vascular damage in systemic sclerosis

Although being classified as autoimmune connective tissue disease, dominant components of the pathophysiology of systemic sclerosis (SSc) consists of mechanisms of vascular damage, which can occur early in the course of the disease. Amongst them are abnormal vasoreactivity, hypoxia, insufficient neoangiogenesis and direct damage of vascular and perivascular cells. They result in a decreased capillary blood flow, and subsequently in clinically overt symptoms such as Raynaud's syndrome and fingertip ulcers. In addition, in active disease vascular pathology can affect various other organs, predominantly the lung, the kidney, the heart but also the gastrointestinal tract. Vascular pathology contributes also significantly to overall morbidity and mortality in SSc patients and reduces life expectancy by at least a decade. Fortunately, molecular biology has revealed a number of underlying pathways on the cellular and subcellular levels, including key factors of the aberrant function of (peri)vascular cells and autoimmune effector cells, the dysregulation of vasoconstrictive molecules and their receptors, the upregulation of intracellular signaling kinases and the altered balance of hypoxia-induced vascular growth factors. This increasing knowledge of vascular pathology in SSc has also resulted in novel therapeutic approaches ranging from endothelin antagonists to application of progenitor cells to counteract this aberrant vascular pathology and to support the repair of the dysfunctional vasculature.

Transcription factor fos-related antigen-2 induces progressive peripheral vasculopathy in mice closely resembling human systemic sclerosis

BACKGROUND

Microvascular damage is one of the first pathological changes in systemic sclerosis. In this study, we investigated the role of Fos-related antigen-2 (Fra-2), a transcription factor of the activator protein-1 family, in the peripheral vasculopathy of systemic sclerosis and examined the underlying mechanisms.

METHODS AND RESULTS

Expression of Fra-2 protein was significantly increased in skin biopsies of systemic sclerosis patients compared with healthy controls, especially in endothelial and vascular smooth muscle cells. Fra-2 transgenic mice developed a severe loss of small blood vessels in the skin that was paralleled by progressive skin fibrosis at 12 weeks of age. The reduction in capillary density was preceded by a significant increase in apoptosis in endothelial cells at week 9 as detected by immunohistochemistry. Similarly, suppression of Fra-2 by small interfering RNA prevented human microvascular endothelial cells from staurosporine-induced apoptosis and improved both the number of tubes and the cumulative tube lengths in the tube formation assay. In addition, cell migration in the scratch assay and vascular endothelial growth factor-dependent chemotaxis in a modified Boyden chamber assay were increased after transfection of human microvascular endothelial cells with Fra-2 small interfering RNA, whereas proliferation was not affected.

CONCLUSIONS

Fra-2 is present in human systemic sclerosis and may contribute to the development of microvasculopathy by inducing endothelial cell apoptosis and by reducing endothelial cell migration and chemotaxis. Fra-2 transgenic mice are a promising preclinical model to study the mechanisms and therapeutic approaches of the peripheral vasculopathy in systemic sclerosis.

Antiphospholipid antibodies and kidney involvement in patients with systemic sclerosis

Antiphospholipid (aPL) antibodies are often detected in systemic autoimmune diseases. The aim of the study was to examine the correlation between the presence of aPL and certain markers of renal function in systemic sclerosis (SSc). Fifty patients (pts) with SSc were examined for the presence of antibodies to cardiolipin (aCL) and to anti-beta 2 glycoprotein I (a-B2GPI) in immunoglobulin M (IgM) and IgG class. Moreover, serum levels of creatinine, cystatin C, and glomerular filtration rate (GFR) were determined in all patients. In all studied pts together, three multiple-regression analyses were performed with one set cystatin C as a dependent variable, in the second GFR according to the Cockcroft-Gault formula and in the third creatinine clearance by Modification of Diet in Renal Disease (MDRD) formula. As independent variables, aPL of either type were inserted in addition to disease duration and age. IgG aCL was significantly positively associated with serum cystatin C (p = 0.002), significantly negatively associated with creatinine clearance according to the Cockcroft-Gault and MDRD formula (p = 0.01 and 0.02, respectively). IgG a-B2GPI was significantly negatively associated with creatinine clearance according to the Cockcroft-Gault (p = 0.03) and MDRD (p = 0.01) formula. IgM aCL and IgM a-B2GPI were not associated with any markers of the renal function. Our study suggests the relationship between kidney involvement and the positivity for some aPL in patients with SSc. Positivity for IgG aCL and IgG a-B2GPI in patients with SSc without secondary antiphospholipid syndrome seems to be connected with decrease of glomerular filtration.

Interstitial lung disease in systemic sclerosis

We reviewed the literature concerning pathogenesis, clinical features, diagnosis and treatment of interstitial lung disease (ILD) in patients with systemic sclerosis (SSc). ILD is detectable in approximately 70% of patients at autopsy. Nonspecific interstitial pneumonia (NSIP) is the most common pathologic finding. The earliest phase of ILD in SSc is characterized by microvascular injury and alveolitis. Endothelial lesions, activation of coagulation proteases, especially thrombin, fibroblast proliferation, and differentiation of normal lung fibroblasts to a myofibroblasts phenotype are hallmarks of ILD in SSc. Diagnostic procedures used to detect ILD are chest X-ray, high-resolution computed tomography, bronchoalveolar lavage, lung function tests, and sometimes thoracoscopic lung biopsy. Novel and potentially useful methods to diagnose ILD in SSc are induced sputum and technetium-labeled diethylenetriamine pentaacetate (99mTC-DTPA) clearance time. Cyclophosphamide seems to be relatively effective to treat ILD in the earliest phase, but the effects of other immunosuppressive drugs on the lungs are less convincing.

BENEFICIAL ROLE OF CURCUMIN IN SKIN DISEASES

In recent years, considerable interest has been focused on curcumin a compound, isolated from turmeric. Curcumin is used as a coloring, flavoring agent and has been traditionally used in medicine and cuisine in India. The varied biological properties of curcumin and lack of toxicity even when administered at higher doses makes it attractive to explore its use in various disorders like tumors of skin, colon, duodenum, pancreas, breast and other skin diseases. This chapter reviews the data on the use of curcumin for the chemoprevention and treatment of various skin diseases like scleroderma, psoriasis and skin cancer. Curcumin protects skin by quenching free radicals and reducing inflammation through nuclear factor-KB inhibition. Curcumin treatment also reduced wound-healing time, improved collagen deposition and increased fibroblast and vascular density in wounds thereby enhancing both normal and impaired wound-healing. Curcumin has also been shown to have beneficial effect as a proangiogenic agent in wound-healing by inducing transforming growth factor-beta, which induces both angiogenesis and accumulation of extracellular matrix, which continues through the remodeling phase of wound repair. These studies suggest the beneficial effects of curcumin and the potential of this compound to be developed as a potent nontoxic agent for treating skin diseases.