Neural blockade, urokinase and prostaglandin E1 combination therapy for acute digital ischemia of progressive systemic sclerosis

The Plasminogen Activator System in Fibroblasts from Systemic Sclerosis

Systemic sclerosis (SSc) is characterized by excessive fibrosis throughout the body. There are two major subsets of SSc, diffuse cutaneous Systemic sclerosis (dSSc) and limited cutaneous Systemic sclerosis (ISSc). Fibroblasts play a key role in SSc. The expression and function of the urokinase (uPA)-mediated plasminogen activation (PA) system, a well-characterized system of serine-proteases involved in several pathological processes, has been investigated in SSc fibroblasts. The expression of the components of the PA system, including uPA, its type-1 and type-2 inhibitors (PAI-1 and PAI-2) and its receptor (uPAR), was examined by Western blot in fibroblasts from patients affected by limited and diffuse forms of SSc. uPA and PAI-1 secretion increased only in fibroblasts from ISSc lesions compared to normal fibroblasts. PAI-2 levels were decreased in fibroblasts from both SSc forms. Interestingly, fibroblasts from areas not adjacent to the lesions (not-affected) of the diffuse form showed reduced levels of PAI-1 and increased uPAR expression. Adhesion experiments showed reduced adherence to VN of fibroblasts from ISSc lesions and from non-affected areas of the diffuse form, as compared to normal controls. These results suggest a role for uPA and PAI-1 in the ISSc form, likely related to the activation of latent forms of cytokines and to the accumulation of ECM components, whereas a role for uPAR can be hypothesized in the evolvement of the diffuse form, based on its up-regulation in the non-affected areas.

Prostaglandin E1 suppresses tumor necrosis factor-alpha and interleukin-10 production by lipopolysaccharides-stimulated mononuclear cells

Prostaglandin E1 has been clinically used in a variety of vascular occlusive diseases. We investigated the in vitro effect of prostaglandin E1 on the synthesis of tumor necrosis factor-alpha, interleukin-1, interleukin-6, interleukin-10 and transforming growth factor beta by human peripheral blood mononuclear cells stimulated with lipopolysaccharides. Prostaglandin E1 significantly suppressed both the mRNA expression and the production of tumor necrosis factor-alpha and interleukin-10 by lipopolysaccharides-stimulated peripheral blood mononuclear cells in a dose-dependent manner (1 x 10(-6)-1 x 10(-8) M). Since tumor necrosis factor-alpha is a potent proinflammatory cytokine involved in certain inflammatory diseases, our findings suggest the possibility to expand the clinical application of prostaglandin E1.

A placebo-controlled study on urokinase therapy in systemic sclerosis

A 4-month randomized placebo controlled trial on urokinase therapy in 36 consecutive systemic sclerosis patients randomly treated with urokinase or placebo was conducted. While patients on placebo did not show any significant improvement, in those following urokinase therapy there was a noticeable improvement in skin sclerosis observed via hand-print and ultrasonography of the skin. Vascular involvement improved: this was demonstrated by capillaroscopy results, showing an improvement in pattern and signs of revascularization and the resolution of skin ulcers. Vascular damage is a typical occurrence in systemic sclerosis cases and various vasoactive drugs are used symptoms for some such as Raynaud's syndrome or skin ulcers. At the moment these drugs seem to constitute the most effective therapy, and have few side effects. We have found only one previous study utilizing urokinase therapy for acute digital ischemia in systemic sclerosis. Our study is the first in which urokinase therapy has been used for the treatment of systemic sclerosis in a large number of patients.