Leukocyte activation in patients with venous insufficiency

Vicious Circle With Venous Hypertension, Irregular Flow, Pathological Venous Wall Remodeling, and Valve Destruction in Chronic Venous Disease: A Review

Substantial advances occurred in phlebological practice in the last two decades. With the use of modern diagnostic equipment, the patients' venous hemodynamics can be examined in detail in everyday practice. Application of venous segments for arterial bypasses motivated studies on the effect of hemodynamic load on the venous wall. New animal models have been developed to study hemodynamic effects on the venous system. In vivo and in vitro studies revealed cellular phase transitions of venous endothelial, smooth muscle, and fibroblastic cells and changes in connective tissue composition, under hemodynamic load and at different locations of the chronically diseased venous system. This review is an attempt to integrate our knowledge from epidemiology, paleoanthropology and anthropology, clinical and experimental hemodynamic studies, histology, cell physiology, cell pathology, and molecular biology on the complex pathomechanism of this frequent disease. Our conclusion is that the disease is initiated by limited genetic adaptation of mankind not to bipedalism but to bipedalism in the unmoving standing or sitting position. In the course of the disease several pathologic vicious circles emerge, sustained venous hypertension inducing cellular phase transitions, chronic wall inflammation, apoptosis of cells, pathologic dilation, and valvular damage which, in turn, further aggravate the venous hypertension.

Factors Influencing Venous Remodeling in the Development of Varicose Veins of the Lower Limbs

One of the early symptoms of chronic venous disease (CVD) is varicose veins (VV) of the lower limbs. There are many etiological environmental factors influencing the development of chronic venous insufficiency (CVI), although genetic factors and family history of the disease play a key role. All these factors induce changes in the hemodynamic in the venous system of the lower limbs leading to blood stasis, hypoxia, inflammation, oxidative stress, proteolytic activity of matrix metalloproteinases (MMPs), changes in microcirculation and, consequently, the remodeling of the venous wall. The aim of this review is to present current knowledge on CVD, including the pathophysiology and mechanisms related to vein wall remodeling. Particular emphasis has been placed on describing the role of inflammation and oxidative stress and the involvement of extracellular hemoglobin as pathogenetic factors of VV. Additionally, active substances used in the treatment of VV were discussed.

VEIN STEP: A Prospective, Observational, International Study to Assess Effectiveness of Conservative Treatments in Chronic Venous Disease

INTRODUCTION

VEIN STEP was conducted to collect international data on the management of chronic venous disease (CVD) and to assess the effectiveness of conservative treatments for the relief of CVD signs and symptoms.

METHODS

This international, observational, prospective, longitudinal, cohort study recruited adult outpatients consulting for symptomatic CVD. The primary objective was the effectiveness of conservative treatments on symptoms, signs and quality of life in a real-life setting assessed using a range of patient-reported outcome measures: 10-cm Visual Analog and Patient Global Impression of Change scales for symptoms; Venous Clinical Severity Score for physician assessment of signs; and 14-item ChronIc Venous Insufficiency Questionnaire (CIVIQ-14) for quality of life. At inclusion, patients were prescribed conservative treatment according to the physicians' usual practice. Follow-up visits took place at weeks 2 and 4, with an optional week 8 visit.

RESULTS

The analysis set comprised 6084 subjects (78% female) from nine countries with a mean age of 50.6 ± 13.8 years and BMI of 28.0 ± 4.9 kg/m2. The most common CEAP classifications were C1 (23.0%), C2 (31.6%), and C3 (30.7%). Conservative therapy consisted of oral venoactive drugs (VADs; 95.8% of subjects) including micronized purified flavonoid fraction (MPFF 75.5%) and diosmin (18.8%), compression (52.0%), and topicals (31.5%). Conservative therapy led to global symptom improvement in 89% of patients after 2 weeks and 96% at 4 weeks. Pain, leg heaviness, cramps, and sensation of swelling were improved in 82%, 71%, 45.5%, and 46% of patients, respectively. Conservative therapy was associated with a decrease over time in patient-assessed global symptom intensity: - 2.37 ± 1.73 (P < 0.001) and physician-assessed disease severity - 1.83 ± 2.82 (P < 0.001). Among the VADs, MPFF-based conservative therapy was associated with the greatest reduction in symptom and sign intensity. Improvements in CIVIQ-14 were observed with all treatments but were greatest for MPFF.

CONCLUSION

In this prospective study conducted in the real-world setting, treatment with conservative therapy, in particular MPFF, was associated with meaningful improvements in the clinical signs and symptoms of disease as well as in quality of life in patients with CVD.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT04574375.

The Effect of Diosmin, Escin, and Bromelain on Human Endothelial Cells Derived from the Umbilical Vein and the Varicose Vein-A Preliminary Study

In this study, we investigated the properties of human varicose vein (VV) endothelial cells (HVVEC) in comparison to the human umbilical vein endothelial cells (HUVEC). The cells were treated with three bioactive compounds with proven beneficial effects in the therapy of patients with VV, diosmin, escin, and bromelain. Two concentrations of tested drugs were used (1, 10 mg/mL), which did not affect the viability of either cell type. Escin led to a slight generation of reactive oxygen species in HUVEC cells. We observed a slight release of superoxide in HVVEC cells upon treatment with diosmin and escin. Diosmin and bromelain showed a tendency to release nitric oxide in HUVEC. Using membrane fluorescent probes, we demonstrated a reduced fluidity of HVVEC, which may lead to their increased adhesion, and, consequently, a much more frequent occurrence of venous thrombosis. For the first time, we show the mechanism of action of drugs used in VV therapy on endothelial cells derived from a VV. Studies with HVVEC have shown that tested drugs may lead to a reduction in the adhesive properties of these cells, and thus to a lower risk of thrombosis.

Understanding Chronic Venous Disease: A Critical Overview of Its Pathophysiology and Medical Management

Chronic venous disease (CVD) is a multifactorial condition affecting an important percentage of the global population. It ranges from mild clinical signs, such as telangiectasias or reticular veins, to severe manifestations, such as venous ulcerations. However, varicose veins (VVs) are the most common manifestation of CVD. The explicit mechanisms of the disease are not well-understood. It seems that genetics and a plethora of environmental agents play an important role in the development and progression of CVD. The exposure to these factors leads to altered hemodynamics of the venous system, described as ambulatory venous hypertension, therefore promoting microcirculatory changes, inflammatory responses, hypoxia, venous wall remodeling, and epigenetic variations, even with important systemic implications. Thus, a proper clinical management of patients with CVD is essential to prevent potential harms of the disease, which also entails a significant loss of the quality of life in these individuals. Hence, the aim of the present review is to collect the current knowledge of CVD, including its epidemiology, etiology, and risk factors, but emphasizing the pathophysiology and medical care of these patients, including clinical manifestations, diagnosis, and treatments. Furthermore, future directions will also be covered in this work in order to provide potential fields to explore in the context of CVD.

Alterations in the Plasma and Red Blood Cell Properties in Patients with Varicose Vein: A Pilot Study

The varicose vein results from the inefficient functioning of the valves in the lower limb veins, making the blood flow slow down and leading to blood stasis and hypoxia. This type of vein dysfunction might be a result of the development of oxidative stress. We compared oxidative stress markers in the plasma and erythrocytes obtained from peripheral veins and varicose veins in the same patients (glutathione, nonenzymatic antioxidant capacity (NEAC), catalase (CAT) and acetylcholinesterase (AChE) activity, thiols, thiobarbituric acid-reactive substance (TBARS), and protein carbonyls). We found a decrease in NEAC in the plasma obtained from the varicose veins compared to the peripheral veins. We detected a decrease in thiols in the plasma, hemolysate, and plasma membranes and increase in protein carbonyl compounds and TBARS levels in the varicose veins. These changes were accompanied by a decrease in CAT and AChE activity. For the first time, our results show changes in the plasma, erythrocyte membrane, and hemolysate protein properties in varicose vein blood in contrast to the plasma and erythrocytes in peripheral vein blood from the same patients. The increased oxidative stress accompanying varicose vein disease might result from the local inefficiency of the antioxidant defense system.

Appropriate Surgical Treatment of Symptomatic Primary Varicose Veins Decreases Systemic Inflammatory Biomarkers

Objective: To evaluate the relationship between systemic inflammatory biomarkers and efficacy of surgical treatment of primary varicose veins of the lower extremities.

Methods: Total 12 patients who underwent endovenous laser ablation or stripping of varicose veins and six healthy subjects were enrolled. Structural and molecular changes of varices were assessed by immunohistochemical staining with anti-monocyte chemotactic protein-1 (MCP-1). MCP-1 and interleukin-6 (IL-6) levels in systemic antecubital blood were measured before and at 12 weeks after treatment.

Results: Immunohistochemical staining revealed prominent manifestation of MCP-1-positive endothelial cells in the walls of varices. Preoperative serum MCP-1 and IL-6 levels in the patients were significantly higher than those in the control (166±12 pg/mL vs 99±10 pg/mL, p=0.003; 5.1±0.95 pg/mL vs 0.0±0.0 pg/mL, p=0.001, respectively). The values were significantly correlated with the severity of chronic venous insufficiency (CVI). Postoperative serum MCP-1 level significantly decreased compared with the preoperative level (152±10 pg/mL vs 166±12 pg/mL, p=0.048). The values after endovenous laser ablation did not significantly decrease compared with those after stripping.

Conclusion: Varicose veins with CVI increase inflammatory biomarker levels in the local tissue and systemic blood. Appropriate treatment of symptomatic varicose veins decreases inflammatory biomarker levels.

Flow cytometric characterization of the saphenous veins endothelial cells in patients with chronic venous disease and in patients undergoing bypass surgery: an exploratory study

Recent findings have suggested that the primary factors for development of chronic venous disease (CVD), which commonly manifests as varicose veins (VV), are due to structural and biochemical modifications of the vessel wall. The aim of this exploratory study was to characterize by flow cytometry the endothelial cells (EC) mechanically extracted from the varicose saphenous veins (VSV) segments of patients submitted to VV surgery, and to compare the expression of cell surface molecules in these EC with that observed in the EC from the graft SV (GSV) of patients undergoing bypass surgery. EC were isolated from distal- (varicose trunk) and from proximal- (nearly normal) VSV segments of 30 patients submitted to VV surgery, and from proximal GSV segments of 20 patients submitted to bypass surgery (control group), using a mechanical method, and their immunophenotype was characterized by flow cytometry. EC were identified as being CD45^negCD146^brightCD31^bright, and analyzed for expression of activation-related (CD54, CD62E, CD106), procoagulant (CD142), and cell junction (CD31, CD146) molecules, and for the scavenger receptor, CD36. The EC harvested from the SV segments of CVD patients had lower expression of all the molecules evaluated, in comparison to controls; these differences were more evident for the EC isolated from the distal-VSV. The EC extracted from the proximal- and distal-VSV segments of the CVD patients also differ from each other, the first having lower levels of CD62E, CD106, CD142 and CD36. Groups did not match for gender and controls were heterogeneous concerning the underlying pathologies, which may have a confounding effect. Our study revealed that the EC isolated from varicose (distal) and nearly normal (proximal) VSV segments of the CVD patients differ phenotypically from each other, and from the EC of the control group. The VSV segments more affected by the CVD have the lowest expression of the studied markers. We hypothesize that CVD is associated with a decrease on the EC surface molecules, causing EC dysfunctionality. Further studies with a large number of gender-matched participants are needed, to confirm the results obtained in this exploratory study.

The haemodynamic causes of skin changes in limbs with primary varicose veins

OBJECTIVES

To investigate the haemodynamic causes of skin changes in limbs with primary varicose veins, which were assessed with air plethysmography.

METHODS

Five hundred seventeen consecutive patients with axial reflux in the great saphenous vein (varicose vein group) and 248 normal subjects (normal group) were investigated. Varicose vein group patients were divided into two groups according to whether they did (C4-6) or did not (C2-3) have skin changes. Several parameters obtained using air plethysmography were compared among the normal group, C2-3 and C4-6 patients.

RESULTS

Although there was no significant difference in the regurgitation index to quantify venous reflux in C2-3 and C4-6 patients, the maximum arterial inflow rate increased (normal group < C2-3 < C4-6), even in limbs with a small amount of venous reflux.

CONCLUSIONS

This study suggests that it is not essential to increase the venous reflux rate in skin change development; rather, it is based on various pathophysiological conditions that increase the arterial inflow rate.

Evaluation of inflammatory cell biomarkers in chronic venous insufficiency

Objective

Inflammation has been implicated as a factor that may contribute to chronic venous insufficiency. The purpose of this study is to compare readily available inflammatory cell biomarkers, with an emphasis on neutrophil count, lymphocyte count, and neutrophil lymphocyte ratio, in patients with chronic venous insufficiency. We hypothesized that circulating leukocyte counts would be higher in the peripheral blood of patients with severe compared to mild chronic venous insufficiency.

Methods

We performed a retrospective medical record review of patients discharged from Ruby Memorial Hospital (Morgantown, WV, USA) with a primary diagnosis of chronic venous insufficiency. Patients were organized into two groups—mild and severe chronic venous insufficiency—based on the Clinical, Etiologic, Anatomic, and Pathophysiological classification system, and inflammatory cell counts were compared between groups.

Results

We observed a significantly higher neutrophil count ( p = .002) and neutrophil-lymphocyte ratio ( p = .005) in patients with severe chronic venous insufficiency compared to mild. Further, the neutrophil–lymphocyte ratio may be a useful predictor of chronic venous insufficiency severity.

Conclusions

We reported significant differences in inflammatory cell biomarkers between mild and severe chronic venous insufficiency, as well as provided support for the use of the neutrophil–lymphocyte ratio as a predictor of chronic venous insufficiency severity. These results may provide clinicians with additional insight to manage chronic venous insufficiency in patients and provide a framework for the development of novel treatment options targeting the immune system in chronic venous insufficiency.

Chronic Venous Insufficiency and the Therapeutic Effects of Daflon 500 mg

Chronic venous insufficiency is linked to venous hypertension and forces of shear stress on the endothelium. Venous hypertension depends upon two forces: the weight of a column of blood from the right atrium transmitted through the valveless vena cava and iliac veins to the femoral vein, and pressure generated by contracting skeletal muscles of the leg transmitted through failed perforating veins. When valve failure occurs in superficial axial veins and perforating veins, the venous pressure in the veins and venules of the skin and subcutaneous tissue is raised. The skin changes in chronic venous insufficiency are directly related to the severity of the venous hypertension. Also, pathologic changes in the valves are linked to venous hypertension and leukocyte infiltration and activation. It is hypothesized that acute venous pressure elevations cause a shift in the venous hemodynamics with changes in wall shear stress. This initiates the inflammatory cascade. Daflon 500 mg ameliorates the effects of chronic inflammation. In randomized trials, 60 days of therapy with Daflon at a dosage of 500 mg 2 tablets daily was effective, in addition to elastic compression, in accelerating venous ulcer healing. Because venous insufficiency is linked to venous hypertension and an inflammatory reaction, it appears that Daflon 500 mg 2 tablets daily shows a great potential for accomplishing blockade of the inflammatory cascade.

Venous Hypertension and the Inflammatory Cascade: Major Manifestations and Trigger Mechanisms

Recent histologic and immunocytochemical evidence of venous leg ulcers supports the hypothesis that lesions observed at different stages of chronic venous insufficiency may be associated with, and possibly caused by, an inflammatory process. Evidence has been obtained that venous valve deficiency may be associated with leukocyte infiltration into valve leaflets; therefore, it is hypothesized that an essential event in the inflammatory cascade is the enzymatic degradation of the valve leaflets and venous wall. The metalloproteinases (MMP) in veins exposed to elevated pressures up to 6 weeks were examined in a rat femoral fistula model with venous hypertension. Zymography shows increased activity of pro-MMP-2 at 3 and 6 weeks. MMP-2 and MMP-9 activity was predominantly observed at days 7 and 21 after creation of the fistula. The degree of extracellular matrix remodeling correlates with the morphological finding of macroscopic lesions. Therefore, the MMP-2 and MMP-9 activation is already present in veins days after exposure to elevated blood pressure and coincides with periods of early alterations in the valve morphology and early forms of reflux.

Chronic Venous Disease and the Leukocyte-Endothelium Interaction: From Symptoms to Ulceration

The mechanisms regulating varicose vein development and the subsequent skin sequelae seen in chronic venous disease (CVD) have been investigated recently. Despite the diversity of signs and symptoms associated with the disease, it seems likely that they are related to venous hypertension. Valvular incompetence is the most important cause of venous hypertension. Recent findings suggest that inflammatory processes are involved in the structural remodeling in venous valves and in the vein wall, leading to valvular incompetence and the development of varicose veins. This has been shown by Ono and colleagues, who found infiltration of valve leaflets and the venous wall by leukocytes (monocytes and tissue macrophages) in all valve specimens from patients with CVD and in none from controls. Further work by Takase and colleagues confirmed this hypothesis. Vein wall remodeling is likely to involve the complex interplay of a range of factors, including an altered ratio between metalloproteinases (MMPs) and their tissue inhibitors (TIMPs), and elevated levels of cytokines and growth factors favor an alteration of the extracellular matrix. Neutrophils and mast cells and their interaction with the venous endothelium are believed to play an important role in the initiation of the inflammatory response in CVD. The transmission of high venous pressures to the dermal microcirculation results in the stimulation of an inflammatory process in which cytokine and growth factor release leads to leukocyte migration into the interstitium and the initiation of further inflammatory events. This process is associated with the intense dermal fibrosis and tissue remodeling seen in chronic venous insufficiency. The many manifestations of the disease are frequently associated with symptoms usually ascribed to CVD. The proportion of patients with symptoms increases with increasing CEAP clinical classes, but the mechanisms underlying symptom appearance have not been elucidated. It has been postulated that it is related to the inflammatory cascade of events seen at all stages of CVD and in which the leukocyte and its interaction with the endothelium play a key role. It is increasingly believed that the emerging twin themes of disturbed venous flow patterns and chronic inflammation underlie and link all the manifestations of the disease. Among the many pathophysiologic mechanisms at work, the leukocyte-endothelium interactions seem to be important in many aspects of the disease and have been identified as a possible target for pharmacologic intervention. Pharmacologic agents that could attenuate various elements of the inflammatory cascade and inhibit the inflammatory process might offer a greater opportunity to prevent future morbidity. It seems reasonable to speculate that such treatment could reduce the risk of CVD progression if applied as soon as the first symptoms appear.

The Appearance of Cytokines and Adhesion Molecules in Saphenous Vein Valves in Chronic Venous Insufficiency

Objective:

To evaluate the difference between competent valves and incompetent valves with regards to the development of expression of cytokines and adhesion molecules in primary varicose veins.

Methods:

Specimens were obtained from 13 patients with primary varicose veins during surgery. Valves were classified according to the angioscopic findings: 8 competent and 17 incompetent valves; type I (7 valves with elongated cusps) and type II (10 valves with expansion of commissures). The mRNA levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), tumour necrosis factor-α (TNF-α), transforming growth factor-β (TGF-β), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and endothelial leucocyte adhesion molecule-1 (ELAM-1) were measured by polymerase chain reaction (PCR) amplification of cDNA reverse-transcribed from RNAs.

Results:

In all cases there were few appearances of IL-6, IL-8 and TNF-α at the valve cusps. TGF-β and VCAM-1 levels were highly elevated in the cusps of incompetent valves compared with competent valves ( p<0.05). At the venous wall IL-6 and IL-8 occurred more frequently in incompetent valves than in competent valves ( p<0.05).

Conclusion:

This study suggests that inflammatory cytokines and adhesions molecules, especially TGF-β, IL-6, IL-8 and VCAM-1, may be related to the occurrence of valve insufficiency.

Dilating venous disease: Pathophysiology and a systematic aspect to different vascular territories

Venous disease is a common but overlooked clinical problem and is an important mortality and morbidity factor depending on the effected vascular territory. Different contributing factors play role on the clinical manifestation of the disease. Peripheral varices of lower extremities, hemorrhoids, varicoceles, pelvic varicose veins are the vasculopathy of veins running toward heart but against gravity. We hypothesize that all these clinical entities share common pathophysiologic steps in terms of vascular wall remodeling and vessel wall damage. A systematic approaches to both arterial and venous dilating disease in further studies and research would increase our understanding on the pathophysiology of dilating vascular disease and would provoke to find out new treatment modalities. Varicose remodeling of veins occurs by a complex interplay of various factors including both physical forces and extracellular matrix remodeling mechanisms. This article focuses on the systematic aspects of dilating venous disease with a focus on pathophysiology under the term of "Dilating Venous Disease".

Role of PTFE Patch Saphenoplasty in Reducing Neovascularization and Recurrence in Varicose Veins

Varicose veins have a high recurrence rate following surgery. Besides poor surgical technique, majority of these recurrences are attributable to neovascularization after both primary and repeat surgery. Authors have studied the effectiveness of a polytetrafluoroethylene (PTFE) patch interposition between the ligated vein stump and the overlying soft tissue at saphenofemoral junction in decreasing recurrence of varicose veins after initial surgery. Study was conducted on 50 patients of varicose veins with saphenofemoral junction incompetence. Patients were randomly divided into two groups, group A and group B alternately. In group A, standard surgical procedure was done followed by PTFE patch application. In group B, same surgical procedure was applied as in group A, with the exception of PTFE patch application. Patients in both groups were given similar postoperative care. A full venous duplex ultrasound assessment was performed in all the patients postoperatively. Neovascularization was observed in five patients (20 %) of group B, while it was not seen in any of the patients in group A at 1-year follow-up. This difference in neovascularization across the two groups was found to be statistically significant with a p value of 0.0251. Hence, authors concluded that patch saphenoplasty helps in reducing recurrence in varicose veins by decreasing neovascularization at saphenofemoral junction.

Provisional Matrix Deposition in Hemostasis and Venous Insufficiency: Tissue Preconditioning for Nonhealing Venous Ulcers

Significance: Chronic wounds represent a major burden on global healthcare systems and reduce the quality of life of those affected. Significant advances have been made in our understanding of the biochemistry of wound healing progression. However, knowledge regarding the specific molecular processes influencing chronic wound formation and persistence remains limited. Recent Advances: Generally, healing of acute wounds begins with hemostasis and the deposition of a plasma-derived provisional matrix into the wound. The deposition of plasma matrix proteins is known to occur around the microvasculature of the lower limb as a result of venous insufficiency. This appears to alter limb cutaneous tissue physiology and consequently drives the tissue into a 'preconditioned' state that negatively influences the response to wounding. Critical Issues: Processes, such as oxygen and nutrient suppression, edema, inflammatory cell trapping/extravasation, diffuse inflammation, and tissue necrosis are thought to contribute to the advent of a chronic wound. Healing of the wound then becomes difficult in the context of an internally injured limb. Thus, interventions and therapies for promoting healing of the limb is a growing area of interest. For venous ulcers, treatment using compression bandaging encourages venous return and improves healing processes within the limb, critically however, once treatment concludes ulcers often reoccur. Future Directions: Improved understanding of the composition and role of pericapillary matrix deposits in facilitating internal limb injury and subsequent development of chronic wounds will be critical for informing and enhancing current best practice therapies and preventative action in the wound care field.

Immunological aspects of chronic venous disease pathogenesis

Chronic venous disease (CVD) is a very common health problem concerning up to 1/3 of the society. Although venous hypertension and valvular incompetence have been long known to be crucial for development of the illness, its exact aetiology remains unclear. Recent findings indicate that inflammatory processes may be crucial for development of incompetent valves and vein wall remodelling. One of the most interesting theories describes “leucocyte trapping” as the mechanism responsible for elevated vein wall permeability and oxidative stress in the veins. At the same time, the cytokine profile of the blood in incompetent veins has not been thoroughly examined. Popular anti-inflammatory drugs relieve some symptoms but do not have much proved effects in prevention and treatment.

We intend to summarize the existing knowledge of the immunological aspects of CVD in order to emphasize its importance for understanding the aetiology of this illness. We also wish to indicate some aspects that remain to be studied in more detail.

Genomics of varicose veins and chronic venous insufficiency

Recent sequencing of the human genome has opened up new areas of investigation for genetic aberrations responsible for the pathogenesis of many human diseases. To date, there have been no studies that have investigated the entire human genome for the genetic underpinnings of chronic venous insufficiency (CVI). Utilizing Gene Chip Arrays we analyzed the relative expression levels of more than 47,000 transcripts and variants and approximately 38,500 well-characterized genes from each of 20 patients (N (CVI)=10; N (Control Group)=10). Relative gene expression profiles significantly differed between patients with CVI and patients unaffected by CVI. Regulatory genes of mediators of the inflammatory reaction and collagen production were up-regulated and down-regulated, respectively in CVI patients. DNA microarray analysis also showed that relative gene expression of multiple genes which function remains to be elucidated was significantly different in CVI patients. Fundamental advancements in our knowledge of the human genome and understanding of the genetic basis of CVI represents an opportunity to develop new diagnostic, prognostic, preventive and therapeutic modalities in the management of CVI.

Venous endothelial injury in central nervous system diseases

The role of the venous system in the pathogenesis of inflammatory neurological/neurodegenerative diseases remains largely unknown and underinvestigated. Aside from cerebral venous infarcts, thromboembolic events, and cerebrovascular bleeding, several inflammatory central nervous system (CNS) diseases, such as multiple sclerosis (MS), acute disseminated encephalomyelitis (ADEM), and optic neuritis, appear to be associated with venous vascular dysfunction, and the neuropathologic hallmark of these diseases is a perivenous, rather than arterial, lesion. Such findings raise fundamental questions about the nature of these diseases, such as the reasons why their pathognomonic lesions do not develop around the arteries and what exactly are the roles of cerebral venous inflammation in their pathogenesis. Apart from this inflammatory-based view, a new hypothesis with more focus on the hemodynamic features of the cerebral and extracerebral venous system suggests that MS pathophysiology might be associated with the venous system that drains the CNS. Such a hypothesis, if proven correct, opens new therapeutic windows in MS and other neuroinflammatory diseases. Here, we present a comprehensive review of the pathophysiology of MS, ADEM, pseudotumor cerebri, and optic neuritis, with an emphasis on the roles of venous vascular system programming and dysfunction in their pathogenesis. We consider the fundamental differences between arterial and venous endothelium, their dissimilar responses to inflammation, and the potential theoretical contributions of venous insufficiency in the pathogenesis of neurovascular diseases.

A systematic review of circulating markers in primary chronic venous insufficiency

OBJECTIVES

The etiology of primary chronic venous insufficiency is poorly understood. This systematic review aimed to summarize published evidence assessing the association of circulating markers with primary chronic venous insufficiency.

METHODS

A search was undertaken through the PubMed database using the terms "venous insufficiency" and "biological marker" or "plasma" or "serum". Search limits included English language, human subjects and studies with publication dates from 1994. Studies which classified patients using the Clinical-Etiology-Anatomy-Pathophysiology system of venous disease were analyzed.

RESULTS

Seventeen studies were included, which have examined > 60 different biomarkers. A total of 13 markers were assessed in >1 study with the number of primary chronic venous insufficiency cases ranging from 41 to 244 and the number of controls ranging from 30 to 144 in these studies. Circulating estradiol, homocysteine and vascular endothelial growth factor were the most consistently associated with primary chronic venous insufficiency.

CONCLUSIONS

Whilst a number of studies have examined biomarkers associated with primary chronic venous insufficiency, further studies are required using improved and standardized approaches on larger populations. Biomarker research may increase pathogenic knowledge and result in opportunities to decrease chronic venous insufficiency burden.

Influence of antioxidant complex on the adhesion of leukocytes in chronic venous insufficiency of lower limbs in rats

OBJECTIVES

In this study, we have evaluated the influence of antioxidant complex (AOC) (dihydroquercetin and lipoic acid) on pool of nonadhesive leukocytes and leukocytes with low and high adhesion in chronic venous insufficiency (CVI) of lower limbs in rats.

MATERIALS AND METHODS

Model of CVI of lower limbs was created by blood flow restriction in caudal vena cava. AOC was administered at 100 mg/kg b.w./day for 14 days p.o. The venous pressure in vena cava and adhesion of leukocytes were estimated on the 14th day of the experiment.

RESULTS

On the 14th day, the venous pressure in groups of animals (experimental and control) was in 2.7-2.9-fold higher. In the control group, the significant increase of leukocytes pool with high adhesion was detected. Intragastric administration of AOC reduced the number of leukocytes with high adhesion and increased the number of nonadhesive leukocytes and leukocytes with a low adhesion.

CONCLUSIONS

Model of CVI of lower limb is accompanied by increased venous pressure and raised adhesion activity of leukocytes. Administration of AOC for 14 days reduces the adhesive activity of leukocytes.

Serum iron concentration and plasma oxidant-antioxidant balance in patients with chronic venous insufficency

Background

The aim of this study was to evaluate serum iron concentration and influence of this element on biomarkers of oxidative stress in patients affected by chronic venous insufficiency (CVI).

Material/Methods

Serum iron (SI) concentration and plasma parameters of oxidant–antioxidant balance (i.e., malonyldialdehyde [MDA], uric acid [UA] concentration, and total antioxidant capacity [TAC]) were compared between 35 patients divided into appropriate groups and 23 healthy individuals.

Results

The subgroups analysis showed that SI concentration was significantly higher only in patients with shorter duration of CVI in comparison with the control group (P=0.013). Significant, negative correlation was found between SI concentration and duration of the disease (r=−0.422, P=0.014), age of the patients (r=−0.542, P=0.001) and BMI (r=−0.408, P=0.018). Mean value of MDA concentration and TAC capacity were higher in patients with CVI in comparison with healthy individuals (P<0.05). UA concentration was decreased, especially in CVI patients with mild clinical stage of disease and shorter CVI duration (P=0.047; P=0.034). There was no significant correlation found between SI concentration and the parameters of oxidant–antioxidant balance.

Conclusions

High concentration of MDA and low UA level in blood of CVI patients suggests that oxidative stress plays an important role in the pathogenesis of the disease. The increase in SI concentration observed in the early stage of CVI can enhance free radicals formation; however, direct evidence has not been provided by the present study.

Does inflammation have a role in the pathogenesis of venous ulcers? A critical review of the evidence

Chronic venous disease, a disorder involving venous return from the legs, is a growing epidemic in the developed world. Numerous studies have been conducted in the past two decades in an attempt to elucidate its underlying pathophysiology. Many theories have been proposed to address the profound inflammatory dysregulation, with the majority focusing on fibrin trap, inflammatory trap, cytokines, growth factors, and matrix metalloproteinases. Although many of these theories have obtained great momentum, much of the data are contradictory. Moreover, many treatments built on these theories have claimed overwhelming success despite insufficient evidence. At the same time, there are few reviews that critically analyze and evaluate these data. Therefore, in this paper, we will provide summaries of the background data and evolution of these theories and examine their supporting evidence.

An unrestrained proinflammatory M1 macrophage population induced by iron impairs wound healing in humans and mice

Uncontrolled macrophage activation is now considered to be a critical event in the pathogenesis of chronic inflammatory diseases such as atherosclerosis, multiple sclerosis, and chronic venous leg ulcers. However, it is still unclear which environmental cues induce persistent activation of macrophages in vivo and how macrophage-derived effector molecules maintain chronic inflammation and affect resident fibroblasts essential for tissue homeostasis and repair. We used a complementary approach studying human subjects with chronic venous leg ulcers, a model disease for macrophage-driven chronic inflammation, while establishing a mouse model closely reflecting its pathogenesis. Here, we have shown that iron overloading of macrophages--as was found to occur in human chronic venous leg ulcers and the mouse model--induced a macrophage population in situ with an unrestrained proinflammatory M1 activation state. Via enhanced TNF-α and hydroxyl radical release, this macrophage population perpetuated inflammation and induced a p16(INK4a)-dependent senescence program in resident fibroblasts, eventually leading to impaired wound healing. This study provides insight into the role of what we believe to be a previously undescribed iron-induced macrophage population in vivo. Targeting this population may hold promise for the development of novel therapies for chronic inflammatory diseases such as chronic venous leg ulcers.

Effects of disturbed flow on vascular endothelium: pathophysiological basis and clinical perspectives

Vascular endothelial cells (ECs) are exposed to hemodynamic forces, which modulate EC functions and vascular biology/pathobiology in health and disease. The flow patterns and hemodynamic forces are not uniform in the vascular system. In straight parts of the arterial tree, blood flow is generally laminar and wall shear stress is high and directed; in branches and curvatures, blood flow is disturbed with nonuniform and irregular distribution of low wall shear stress. Sustained laminar flow with high shear stress upregulates expressions of EC genes and proteins that are protective against atherosclerosis, whereas disturbed flow with associated reciprocating, low shear stress generally upregulates the EC genes and proteins that promote atherogenesis. These findings have led to the concept that the disturbed flow pattern in branch points and curvatures causes the preferential localization of atherosclerotic lesions. Disturbed flow also results in postsurgical neointimal hyperplasia and contributes to pathophysiology of clinical conditions such as in-stent restenosis, vein bypass graft failure, and transplant vasculopathy, as well as aortic valve calcification. In the venous system, disturbed flow resulting from reflux, outflow obstruction, and/or stasis leads to venous inflammation and thrombosis, and hence the development of chronic venous diseases. Understanding of the effects of disturbed flow on ECs can provide mechanistic insights into the role of complex flow patterns in pathogenesis of vascular diseases and can help to elucidate the phenotypic and functional differences between quiescent (nonatherogenic/nonthrombogenic) and activated (atherogenic/thrombogenic) ECs. This review summarizes the current knowledge on the role of disturbed flow in EC physiology and pathophysiology, as well as its clinical implications. Such information can contribute to our understanding of the etiology of lesion development in vascular niches with disturbed flow and help to generate new approaches for therapeutic interventions.

The inflammatory reaction during chronic venous disease of lower limbs

Chronic venous disease (CVD) is an insufficiency of distal veins caused by their partial or total obstruction, endothelial distension and functional disorders. Chronic venous disease of lower limbs is common problem and affects millions of people. In this article we suggest that inflammatory process is involved in the structural remodeling in venous valves and in the venous wall, leading to valvular incompetence and the development of varicose veins.

Mechanisms of varicose vein formation: valve dysfunction and wall dilation

Varicose veins are a common venous disease of the lower extremity. Although the mechanisms and determinants in the development of varicosities are not clearly defined, recent clinical studies and basic science research have cast some light on possible mechanisms of the disease. In varicose veins, there are reflux and incompetent valves as well as vein wall dilation. Primary structural changes in the valves may make them ‘leaky’, with progressive reflux causing secondary changes in the vein wall. Alternatively, or concurrently, the valves may become incompetent secondary to structural abnormalities and focal dilation in vein wall segments near the valve junctions, and the reflux ensues as an epiphenomenon. The increase in venous pressure causes structural and functional changes in the vein wall that leads to further venous dilation. Increase in vein wall tension augments the expression/activity of matrix metalloproteinases (MMPs), which induces degradation of the extracellular matrix proteins and affect the structural integrity of the vein wall. Recent evidence also suggests an effect of MMPs on the endothelium and smooth muscle components of the vein wall and thereby causing changes in the venous constriction/relaxation properties. Endothelial cell injury also triggers leukocyte infiltration, activation and inflammation, which lead to further vein wall damage. Thus, vein wall dilation appears to precede valve dysfunction, and the MMP activation and superimposed inflammation and fibrosis would then lead to chronic and progressive venous insufficiency and varicose vein formation.

Mechanisms in Experimental Venous Valve Failure and their Modification by Daflon© 500 mg

OBJECTIVES

To characterize the acute response of the vein wall to venous hypertension and associated altered fluid shear stress and to test the effect of micronized purified flavonoid fraction (MPFF, Daflon 500), on this response.

MATERIAL AND METHODS

A femoral arteriovenous fistula was created in Wistar rats (n=48). A cohort of 24 rats received oral treatment with MPFF (100 mg/kg/day body weight), 24 rats underwent the arteriovenous fistula procedure and received no treatment. At days 1, 7 and 21 the animals (n=8 at each time point) were killed. Experimental parameters measured included limb circumference, blood flow at the sapheno-femoral junction, leukocyte infiltration and gelatinase activity (matrix metalloproteinase, MMP).

RESULTS

The acute rise in venous hypertension was accompanied by limb edema and venous reflux together with an eventual loss of valve leaflets in the saphenous vein. There was an increase in granulocyte and macrophage infiltration into the venous wall and the surrounding tissue, and a lesser increase in T- and B-lymphocyte infiltration. These changes were accompanied by a local increase in the proteolytic enzymes, MMP-2 and MMP-9. Administration of MPFF reduced the edema and lessened the venous reflux produced by the acute arteriovenous fistula. Decreased levels of granulocyte and macrophage infiltration into the valves were also observed compared with untreated animals.

CONCLUSIONS

Venous hypertension caused by an arteriovenous fistula resulted in the development of venous reflux and an inflammatory reaction in venous valves culminating in their destruction. MPFF was able to delay the development of reflux and suppress damage to the valve structures in this rat model of venous hypertension.

Molecular mechanisms in chronic venous insufficiency

Chronic venous disease (CVD) is common. Its manifestations include varicose veins; skin changes such as dermatitis, hyperpigmentation, and lipodermatosclerosis; and chronic leg ulcers. Recent advances in the understanding of its pathophysiology have shown how molecular mechanisms in the inflammatory cascade are involved in these diverse findings. Venous hypertension and associated fluid shear stress alterations on the endothelial surface may initiate this cascade and may lead to adverse changes in the venous wall, venous valves, and skin that can eventually result in varicose veins and in venous ulcers.

[Pathophysiology of pain in venous disease]

Pain is the leading complaint of patients with venous disease. It has a significant effect on the patient's quality-of-life. For the clinician and the researcher however it is difficult to apprehend how pain is related to the venous disease, both because of the multiple factors involved and because of the lack of any strong relationship between pain symptoms and the severity of the venous disease. Currently, several hypotheses concerning the pathogenesis of pain in venous disease have focused on the causal impact of local inflammation. Over the last five years, a large body of evidence has been accumulation showing an inflammatory reaction around varicose veins, but the precise mechanism of how inflammatory mediators interact with venous nociceptors, which might explain part of the variability in pain observed in venous disease, remains elusive, both clinically and experimentally.

A previously unrecognized protein-protein interaction between TWEAK and CD163: potential biological implications

TWEAK (TNF-like weak inducer of apoptosis) is a TNF superfamily member implicated in several mechanisms. Although fibroblast growth factor inducible 14 (Fn14)/TweakR has been reported as its receptor, an as yet unrecognized surface molecule(s) might modulate TWEAK function(s). Thus, we set out to identify TWEAK-binding proteins by screening a combinatorial peptide library. Cyclic peptides containing a consensus motif (WXDDG) bound to TWEAK specifically. These peptides were similar to CD163, a scavenger receptor cysteine-rich domain family member, restricted to the monocyte/macrophage lineage and responsible for the uptake of circulating haptoglobin-hemoglobin (Hp-Hb) complexes. Sequence profile analysis suggested that TWEAK mimicked the CD163 natural ligand (Hp-Hb). Consistently, we show dose-dependent TWEAK binding to CD163 and blockade by an anti-CD163 Ab. In a competition assay, both soluble CD163 and Fn14/TweakR were able to compete off TWEAK binding to coated Fn14/TweakR or CD163, respectively. Flow-cytometry and immunofluorescence assays showed that human monocytes (Fn14/TweakR negative and CD163 positive) bind TWEAK, thus blocking the recognition of CD163 and reducing the activation mediated by a specific mAb in these cells. We demonstrate that monocytes can sequester TWEAK from supernatants, thus preventing tumor cell apoptosis; this effect was reverted by preincubation with the peptide mimicking CD163 or with a mAb anti-CD163, indicating specificity. Finally, we show that recombinant human TWEAK binding to CD163-transfected Chinese hamster ovary cells is inhibited by the presence of either unlabeled TWEAK or the Hp-Hb complex. Together, these data are consistent with the hypothesis that CD163 either acts as a TWEAK scavenger in pathological conditions or serves as an alternate receptor for TWEAK in cells lacking Fn14/TweakR.

Venous hypertension induces increased platelet reactivity and accumulation in patients with chronic venous insufficiency

The objective of this study was to determine whether there are changes in platelet activation and rheology in patients with chronic venous insufficiency (CVI) and what their impact is on this disease. Anticoagulated peripheral venous blood collected from 21 patients with CVI and 13 normal control subjects in different bodily positions was incubated either with 0.5 mumol/L adenosine diphosphate (ADP) or without agonist and analyzed by whole blood flow cytometry. Soluble P-selectin was analyzed in obtained sera by enzyme-linked immunosorbent assay. Platelet count was determined by a whole blood analyzer. Circulating platelets were more reactive to stimulation with 0.5 mumol/L ADP in patients with CVI compared with control subjects. There was no statistically significant change in platelet activation without ADP and the level of soluble P-selectin as a function of posture. Under simulated venous hypertension, platelet accumulation was observed in patients with CVI. Patients with CVI had increased platelet reactivity and accumulation during orthostasis, suggesting this might be a contributory factor to CVI pathogenesis.

Causes of telengiectasias, reticular veins, and varicose veins

Study of surgical specimens and direct observation by angioscopy has revealed that the varicose venous wall, the valvular annulus, and the valves themselves undergo profound changes. Morphologic investigations have shown dilation of the valve annulus, bulging valve leaflets, commissural dilation, leaflet stretching, and eventually complete destruction of the valves. The venous wall has been seen to undergo changes of thickening in some segments and thinning in others. Our investigations show that inflammation and subsequent remodeling of the venous valves and wall are the fundamental mechanisms underlying the observed lesions. Hemodynamic forces, such as blood pressure changes in the wall and sheer stress, as well as varying planes of laminar and turbulent flow, induce activation of leukocytes and endothelial cells. Integrins appear to act as intermediaries and expression of adhesion molecules has been observed. Breakdown of extracellular matrix of the media and adventitia through activation of matrix metalloproteases (MMP) has been observed. In particular, expressions of MMP-1, MMP-2, MMP-9, and tissue inhibitor of metalloproteinase have been studied. Telangiectasias, reticular veins, and true varicose veins appear to be a consequence of the changes induced by venous hypertension and sheer stress.

Venous Hypertension, Inflammation and Valve Remodeling

OBJECTIVES

To identify possible mechanisms for destruction of valves in chronic venous hypertension and the results of treatment with an anti-inflammatory micronized purified flavonoid fraction.

MATERIAL AND METHODS

The saphenous vein valves in a rat model of venous hypertension caused by a femoral arterial-venous fistula were studied. Studies included femoral venous pressure, valve morphology, femoral venous reflux and selected molecular inflammatory markers as examined by immunohistochemistry. The effects of treatment with the anti-inflammatory micronized purified flavonoid fraction (S 5628, Servier, 50 and 100 mg/kg/day) were investigated.

RESULTS

The femoral venous pressure was elevated close to arterial values for a period of 3 weeks. We then examined the morphology of the veins and selected molecular inflammatory markers were assessed. The results show that in this model venous reflux develops in response to venous hypertension. This can be inhibited by the administration of the anti-inflammatory micronized purified flavonoid fraction (S 5628, Servier, 50 and 100 mg/kg/day). The valve becomes incompetent by a combination of venous dilation and shortening of the valve leaflets. This is not inhibited by treatment with S 5628. The valve leaflets are infiltrated with granulocytes, monocytes and T-lymphocytes, and the endothelial cells express enhanced levels of P-selectin and ICAM-1. Cells in the valves are subject to extensive apoptosis although no enhancement of MMP 2,9 expression could be detected at the three-week time point examined in this study.

CONCLUSIONS

These results indicate that in this model chronic elevation of venous pressure is associated with an inflammatory reaction in venous valves, a process that may lead to their dysfunction, reflux, and upstream elevation of venous pressure. These effects are mitigated by the anti-inflammatory micronized purified flavonoid fraction in a dose dependent manner.

The effect of transport stress on neutrophil activation in wild badgers (Meles meles)

Wild badgers (Meles meles) in Wytham woods, Oxfordshire, are routinely trapped, transported to a central field laboratory, studied and released as part of an on-going population study. These procedures have been carefully developed to minimise impact on the badgers' welfare; however they are potentially stressful, and, as part of our on-going welfare refinements, and our exploration to develop methods for quantifying stress in wild mammals, we studied the effects of transport stress on neutrophil activation in wild trapped badgers. Blood samples were obtained from 28 badgers. We compared three transport regimes: transported (n = 9), transported and rested for at least 30 mins (n = 11), and not transported (n = 8). Total and differential white cell counts were carried out and neutrophil activation was measured by the nitroblue tetrazolium test. Our goal was primarily to validate neutrophil activity as an indicator of stress, on the basis that the transport treatment was expected to be more stressful than the non-transport treatment. There were significant increases in % activated circulating neutrophils in response to transport. This study supports the proposition that stress affects circulating neutrophil numbers and the state of their activation, as determined by the nitroblue tetrazolium reduction assay, and therefore adds weight to the idea that neutrophil activation is a potential measure of stress in wild animals.

Great saphenous vein stripping with liberal use of subfascial endoscopic perforator vein surgery (SEPS)

This study is based on a unique registry of 632 patients who underwent great saphenous vein (GSV) stripping and liberal use of subfascial endoscopic perforator vein surgery (SEPS) for minimal to severe lower limb venous insufficiency. Clinical examinations and color-coded duplex scanning were performed on a randomly selected, manageable sample of 170 limbs to assess the affect of early SEPS on junctional (saphenofemoral [SFJ] and/or saphenopopliteal [SPJ]) and perforator vein (PV) insufficiencies and superficial varicosities at a median of 6.5 years. PV incompetence was present in 68 legs (40%), as the sole transfascial insufficiency in 28 limbs and combined with SFJ or SPJ incompetence in 40 limbs. Junction incompetence alone characterized an additional 38 limbs, bringing the total transfascial insufficiency prevalence to 62%. Superficial varicosities affected 46% of limbs. Overall CEAP clinical class was unimproved beyond preoperative values. PV incompetence was associated with higher CEAP and clinical venous severity scores than were junctional insufficiencies alone. We concluded that PV incompetence alone or combined with junctional insufficiency is associated with increased symptoms and disease progression. The prevalence of SFJ, SPJ, and PV incompetence (62%) and recurrent varicosities (46%) suggests that early use of SEPS does not prevent disease progression and offers no benefit over GSV stripping in the absence of deep vein insufficiency or threatened ulceration.

Surgical treatment of venous ulcers: role of subfascial endoscopic perforator vein ligation

Existing data in the literature lack answers to several questions about the optimal treatment of patients with advanced CVI, especially venous ulcers. There is no level I evidence to support the superiority of surgical over medical treatment and the extent of surgical intervention. Specifically, knowledge about the efficacy and applicability of SEPS is incomplete, and prospective, randomized studies are needed. In the light of present-day knowledge, all patients should undergo a trial of medical management before resorting to surgery. Patients who benefit from surgical treatment and the addition of SEPS, if indicated, are patients with ulcers resulting from PVI of the superficial and perforating veins, with or without DVI. Based on available data, these patients can be assured an 80% to 90% chance of long-term freedom from ulcer recurrence. Despite subjective symptomatic and objective clinical score improvement, the role of surgery and SEPS is controversial in patients with PT because only 50% of patients can be predicted to have long-term freedom from ulcer recurrence. Patients with ulcer recurrence after SEPS should undergo duplex scanning to exclude recurrent or persistent perforators. If these are found to be incompetent, repeat SEPS is warranted. If there is no perforator incompetence, patients should be considered for deep venous reconstruction.

Micronised purified flavonoid fraction: a review of its use in chronic venous insufficiency, venous ulcers and haemorrhoids

Micronised purified flavonoid fraction (MPFF) [Daflon 500 mg], an oral phlebotropic drug consisting of 90% micronised diosmin and 10% flavonoids expressed as hesperidin, improves venous tone and lymphatic drainage, and reduces capillary hyperpermeability by protecting the microcirculation from inflammatory processes. The absorption of diosmin is improved by its micronisation to particles with a diameter <2 microm. Compared with placebo, MPFF 500 mg twice daily significantly decreased ankle or calf circumference, and improved many symptoms of chronic venous insufficiency (CVI) and plethysmographic parameters in two randomised, double-blind, 2-month studies. Improvement in symptoms was parallelled by an improvement in health-related quality of life in a nonblind, 6-month trial. Significantly more venous leg ulcers </=10 cm in diameter completely healed with MPFF 500 mg twice daily plus standard management (compression and local treatment) for 2-6 months than with standard management alone or with placebo in a nonblind and a double-blind trial. The addition of MPFF to standard management was cost effective in a retrospective pharmacoeconomic analysis of the 6-month trial. Compared with placebo, the duration and/or intensity of individual symptoms of grade 1 or 2 acute internal haemorrhoids improved significantly with 3 tablets of MPFF 500 mg twice daily for 4 days then 2 tablets of MPFF 500 mg twice daily for 3 days. Two tablets of MPFF 500 mg daily for 60 or 83 days reduced the frequency, duration and/or severity of acute haemorrhoidal symptoms and improved the overall signs and symptoms of chronic (recurrent) haemorrhoids compared with placebo. Compared with a control group, MPFF significantly reduced the risk of secondary bleeding after elective haemorrhoidectomy. In clinical trials, MPFF had a tolerability profile similar to that of placebo; the most frequently reported adverse events were gastrointestinal and autonomic in nature. In conclusion, MPFF is a well established and well tolerated treatment option in patients with CVI, venous ulcers, or acute or chronic internal haemorrhoids. MPFF is indicated as a first-line treatment of oedema and the symptoms of CVI in patients in any stage of the disease. In more advanced disease stages, MPFF may be used in conjunction with sclerotherapy, surgery and/or compression therapy, or as an alternative treatment when surgery is not indicated or is unfeasible. The healing of venous ulcers </=10 cm in diameter is accelerated by the addition of MPFF to standard venous ulcer management. MPFF may reduce the frequency, duration and/or intensity of symptoms of grade 1 or 2 acute internal haemorrhoids, and also the severity of the signs and symptoms of chronic haemorrhoids.

Endothelium and Venotropic Drugs in Chronic Venous Insufficiency: A Review

Objective:

To review the literature concerning chronic venous disease of the leg and the mechanisms of action of venotropic drugs.

Methods:

The authors identified relevant papers from their own collection and from medical literature databases.

Synthesis:

Endothelial cell activation caused by ex-posure to the hypoxic conditions that develop during blood stasis in chronic venous insufficiency patients is proposed to be one factor initiating a pro-inflammatory process in the leg veins. Recruited and activated neutrophils would then be responsible for alterations of the venous wall, typical of what is observed in varicose veins. Venotropic drugs used in the treatment of chronic venous insufficiency patients have long been known to decrease vascular permeability and increase venous tone. Recently, it has been shown that they are also able to prevent endothelial cell activation by hypoxia and a precise biochemical target common to all of them has been identified: the mitochondrial respiratory chain.

Conclusion:

The influence of venotropic drugs on the mitochondrial respiratory chain provides a rational explanation for the therapeutic benefit to patients of this class of drugs.

Generation of reactive oxygen metabolites by the varicose vein wall

OBJECTIVES

to evaluate the content of lipid peroxidation products (expressed by the concentration of thiobarbituric acid-reactive substances; TBARS), the content of myeloperoxidase (MPO), and the localisation of xanthine oxidase (XO) in varicose veins (vv), varicose veins with superficial thrombophlebitis and unchanged saphenous veins.

METHODS

varicose saphenous veins, varicose veins with superficial thrombophlebitis and normal saphenous veins obtained during varicose vein surgery on 36 patients as well as healthy saphenous veins from cadaver organ donors (control). Homogenates were prepared in which TBARS concentration and MPO content were determined. Immunohistochemical staining to detect XO was also performed.

RESULTS

the highest concentration of TBARS occurred in vv with superficial thrombophlebitis, the lowest in donor vein. The highest content of MPO was observed in vv and slightly lower - in varicose veins with thrombophlebitis. A positive reaction for XO was seen in vv wall endothelium. Specimens of vv with thrombophlebitis revealed strong, intense staining in endothelium as well as in vasa vasorum.

CONCLUSIONS

varicose veins, especially those complicated with superficial thrombophlebitis revealed increased free radical generation. Its sources might be neutrophils, and in vv complicated with superficial thrombophlebitis-xanthine oxidase.