Glycosaminoglycan sulodexide modulates inflammatory pathways in chronic venous disease

Inflammation represents an important epiphenomenon in the etiopathogenesis of chronic venous disease, a worldwide debilitating condition affecting millions of subjects. The pathophysiology of chronic venous disease (CVD) is based on the hemodynamic abnormalities in conjunction to alterations in cellular and extracellular matrix biocompounds. The endothelial dysfunction results from early perturbation in the endothelium linked to glycocalyx injury and promoted by inflammatory cells and mediators (such as matrix metalloproteinases and interleukins), which lead to progressive dilation of the vein resulting in chronic venous insufficiency. Activated leukocytes during the inflammatory process release enzymes, free radicals, chemokines and inflammatory cytokines in the vessel microenvironment, which are responsible for the changes of the venous wall and venous valve, reflux and venous hypertension, and the development/progression of tissue destruction and skin changes. Sulodexide, a highly purified mixture of glycosaminoglycans composed by 80% fast moving heparin and 20% of dermatan sulphate, exhibits anti-thrombotic and profibrinolytic properties, restoring also the essential endothelial glycocalyx. Glycosaminoglycan sulodexide has been also characterized to reduce the release of inflammatory cytokines/chemokines and to inhibit the matrix metalloproteinases-related proteolytic cascades, counteracting endothelial dysfunctions. The pleiotropic effects of sulodexide set the basis for a very promising agent in treating the spectrum of CVD.

The Impact of Gastrocnemius Muscle Cell Changes in Chronic Venous Insufficiency

OBJECTIVE

To investigate the pathological and metabolic changes in the gastrocnemius muscle in patients with chronic vein insufficiency (CVI).

METHOD

Thirty-six patients with varicose veins were investigated by ambulatory venous pressure (AVP) and duplex ultrasonography. Twelve age and height-matched controls were used for comparison. Patients and controls consented to participate in this study. Twenty-one patients with primary vein varicose (group AI) and 15 patients (group AII) with primary deep venous valve incompetence (DVI) underwent biopsies of the gastrocnemius muscle during operation. Adductor biopsies obtained from the same limbs served as a control group (group B) and specimens from controls subjects without venous disease served as the second control group (group C). All the specimens were investigated by superoxide dismutase (SOD), nitric oxide (NO), Na+-K+-ATPase, Ca2+-ATPase and lactic acid (LD) determinations. Samples were subjected to light and electron microscopy following H & E staining, special ATPase, cytochrome oxidase/succinate dehydrogenase (COX/SDH) stains.

RESULTS

Normal muscle architecture was seen following H & E, ATPase and COX/SDH staining and normal cell metabolism was observed in specimens of groups B and C. In group A, pathological changes were encountered in the gastrocnemius muscle including disseminated myofibril atrophy, cell denaturation and necrosis, inflammatory cell infiltration, proliferation and dilation of interfascicular veins. ATPase staining (pH 9.4) demonstrated grouping of atrophic fibres, especially type I myofibril grouping, accompanied by moderate to severe atrophy of type II muscle fibres. However, no patient had selective type I fibre atrophy. Enhanced enzymatic activity in single or multiple myofibrils was demonstrated by COX/SDH staining in approximately half of the specimens in group AII. In group AII, electron microscopy showed swelling, myelin figure denaturation of mitochondria, disruption of the myofibrils and increased lipid droplets in the gastrocnemius muscle. Increased concentration of LD was found in most specimens from group A patients. There were also reductions of SOD, NO, biochemical activity of Na+-K+-ATPase, Ca2+-ATPase with increasing concentration of LD in these patients, most prominently in group AII. We found correlation between AVP assessments and the biochemical measurements as well as morphological appearances of the gastrocnemius muscle.

CONCLUSION

Venous hypertension results in pathophysiological changes in the gastrocnemius muscles of patients with DVI, associated with decreased calf pump function.

Immunocytochemical characterisation of the inflammatory cell infiltrate of varicose veins

OBJECTIVES

To characterise the inflammatory cell infiltrate in varicose vein wall, and its relationship to the valve complex.

DESIGN

A comparative study of the distribution of inflammatory cells in normal and varicose vein.

MATERIALS

Specimens of proximal human long saphenous vein were obtained from patients with duplex Doppler confirmed long saphenous vein reflux (n=14). Control vein was obtained from patients undergoing coronary artery bypass without clinical evidence of venous insufficiency (n=6). Longitudinal 7 microm frozen sections of vein, displaying valve, were prepared.

METHODS

Using immunohistochemistry, T-lymphocytes (CD3), macrophage/monocytes (CD68), neutrophils (CD15s) and mast cells (anti-mast cell tryptase) were identified. The number of cells per unit length vein were counted using light microscopy.

RESULTS

There were significantly more mast cells and macrophage/monocytes in varicose vein as compared to control. There was a non-significant trend towards more T-lymphocytes in varicose vein. Few neutrophils were present in varicose or normal vein. The distribution of inflammatory cells with respect to the valve was not found to be significant.

CONCLUSIONS

Varicose veins display a greater inflammatory cell infiltrate than normal vein. The key role of macrophage/monocytes and mast cells in tissue damage and remodelling should stimulate further research into whether they play a significant role in the development of chronic venous insufficiency.

Treatment of varicose veins: an assessment of intraoperative and postoperative compression sclerotherapy

Since thrombotic complications, such as superficial thrombophlebitis and subsequent skin pigmentation, are common after sclerotherapy, we conducted a study to evaluate whether combining sclerotherapy with ligation of varicose veins minimizes complications and what timing for sclerotherapy would be most beneficial-accompanying surgery or several weeks postsurgery. Surgical intervention and compression sclerotherapy were performed consecutively on 111 limbs (group A), and sclerotherapy was performed 28 days after surgical intervention on 87 limbs (group B). The volume of sclerosant used and the frequency of complications (thrombus formation and pigmentation) were analyzed. Plasma levels of thrombin-antithrombin III complex (TAT) and D-dimer (DD), as markers for activation of coagulation, were compared. In group A, the total volume of sclerosant used in patients with complications was significantly higher than that in patients without complications. The frequency of thrombus formation and of pigmentation was significantly lower (p <0.01) in group B (10% and 18%, respectively) than in group A (21% and 37%, respectively). The plasma levels of TAT 7 days after treatment were significantly lower in group B (3.4 +/- 1.2 mg/L) than in group A (4.9 +/- 1.1 mg/L). Performing compression sclerotherapy 28 days after surgical intervention is effective for reducing complications and a good alternative for patients with an underlying hypercoagulable state.

Matrix metalloproteinase-9 and urokinase-type plasminogen activator in varicose veins

The purpose of this study was to evaluate the roles of matrix metalloproteinases (MMPs) and urokinase-type plasminogen activator (uPA) with regard to varicose veins (VVs). Immunohistochemical staining and ELISA were performed on samples from 73 patients with the following leg VVs: 82 greater saphenous veins (GSV) from the groin (GSV groin), 28 GSV from the ankle (GSV ankle), 85 VVs, and 13 normal GSV groin (control [CR]) obtained during coronary artery bypass surgery. Immunohistochemically, MMP-9 was localized in the smooth muscle cells (SMCs) in the tunica media. The ratio of immunopositive cells of MMP-9 in the GSV groin, VVs, and GSV ankle were significantly higher than that of CR. The ratios of immunopositive cells of uPA and uPA receptor (uPAR) were not significantly different among the groups. uPA and uPAR were found to be positive in a different set of SMCs of the MMP-9-positive cells. An ELISA showed that the amount of uPA in the culture of the GSV groin was significantly higher than that in CR. For the remodeling process, MMP-9 may be produced in the VV wall and degrade elastic lamellae and other extracellular components of the venous wall. uPA may be produced by groin tissue of the GSV and flow downward because of valvular incompetence, activating MMP-9 at VV tissues.

Circulating leucocyte adhesion molecules in chronic venous insufficiency

BACKGROUND

Enzyme-linked immunosorbent assay (ELISA) techniques have detected the existence of circulating forms of intercellular adhesion molecule-1 (ICAM-1), vascular endothelial adhesion molecule-1 (VCAM-1) and E-selectin, all of which mediate leucocyte-endothelial adhesion. This study determined whether circulating cell adhesion molecules were increased in patients with chronic venous insufficiency (CVI) which causes venous stasis.

PATIENTS AND METHODS

Before and after walking and upon recovery blood samples were drawn from the saphenous vein in 20 CVI patients: 10 with varicose veins (group 1), 10 with deep venous insufficiency (group 2). 10 healthy controls were enrolled. The total leucocyte count and the soluble levels of ICAM-1, VCAM-1 and E-selectin were determined.

RESULTS

After walking, the total leucocyte count decreased significantly (p < 0.01) only in group 2 and sICAM-1 and sVCAM-1 increased significantly (p < 0.01). Upon recovery, these significant differences remained in group 2. No significant modification was observed at any stage of the study in group 1 or in the control group.

CONCLUSIONS

These results suggest persistently high levels of circulating adhesion molecules may contribute to worsen microvascular perfusion, which leads to the onset of trophic damage in CVI.

Endothelial activation response to oral micronised flavonoid therapy in patients with chronic venous disease--a prospective study

BACKGROUND

Endothelial activation is important in the pathogenesis of skin changes due to chronic venous disease (CVD). Purified micronised flavonoid fraction has been used for symptomatic treatment of CVD for a considerable period of time. The exact mode of action of these compounds remains unknown.

AIM

To study the effects of micronised purified flavonoidic fraction (Daflon 500 mg, Servier, France) treatment on plasma markers of endothelial activation.

MATERIALS AND METHODS

Twenty patients with chronic venous disease were treated for 60 days with DAFLON 500 mg twice daily. Duplex ultrasonography and PPG was used to assess the venous disease. Blood was collected from a foot vein immediately before starting treatment and within 1 week of stopping treatment. Plasma markers of endothelial activation were measured using commercial ELISA kits.

RESULTS

Reduction in the level of ICAM-1, 32% (141 ng/ml: 73 ng/ml) and VCAM 29% (1292 ng/ml: 717 ng/ml) was seen. Reduction in plasma lactoferrin (36% decrease, 760 ng/ml: 560 ng/ml) and VW factor occurred in the C4 group only.

CONCLUSIONS

Micronised purified flavonoidic fraction treatment for 60 days seems to decrease the levels of some plasma markers of endothelial activation. This could ameliorate the dermatological effects of (CVD). This could also explain some of the pharmacological actions of these compounds. Our study demonstrates the feasibility of using soluble endothelial adhesion molecules as markers for treatment.

Studies on an immunologic method for the diagnosis of varicose veins

A glycoprotein fraction was isolated from varicose veins by a successive extraction procedure. Antibodies to this fraction were shown to exist in the serum of persons suffering from varicose veins. The pathology of this illness is discussed in relation to the autoimmune reaction, and the basis for a method for the early diagnosis of varicose veins is proposed.