Smooth Muscle Cell Apoptosis in Primary Varicose Veins

Transfer RNA-derived fragment tRF-36 modulates varicose vein progression via human vascular smooth muscle cell Notch signaling

Varicose veins are a prevalent vascular disorder affecting millions of individuals worldwide, and we previously reported transfer RNA-derived fragment (tRF) involvement in varicose veins. This study investigated the role of tRF-36 in varicose vein pathogenesis. Varicose veins and adjacent normal vascular tissues were collected to measure the expression of Notch 1, 2, and 3 and the smooth muscle cell (SMC) markers SMA-α, and SM22α. Human vascular SMCs (HVSMCs) were transfected to alter tRF-36 levels and examine the effects on Notch 1-3, tRF-36, SMA-α, and SM22α expression. Notch 1-3 and tRF-36 levels were higher in varicose veins than in adjacent normal vascular tissues. tRF-36 knockdown decreased HVSMC viability, downregulated Notch 1, 2, and 3 expression, and upregulated SMC markers (SMA-α and SM22α) compared with control HVSMCs. When the Notch pathway was inhibited, the expression of tRF-36 was significantly reduced. Additionally, Notch pathway inhibition showed similar effects to tRF-36 knockdown on HVSMC viability and the expression of SMA-α and SM22α. Furthermore, a Notch pathway inhibitor reversed the effects of the tRF-36 mimic on HVSMCs. Our study suggests a critical role for tRF-36 in varicose veins and demonstrates that tRF-36 knockdown may suppress varicose vein progression by inhibiting the Notch signaling pathway.

Glycocalyx disruption, endothelial dysfunction and vascular remodeling as underlying mechanisms and treatment targets of chronic venous disease

The glycocalyx is an essential structural and functional component of endothelial cells. Extensive hemodynamic changes cause endothelial glycocalyx disruption and vascular dysfunction, leading to multiple arterial and venous disorders. Chronic venous disease (CVD) is a common disorder of the lower extremities with major health and socio-economic implications, but complex pathophysiology. Genetic aberrations accentuated by environmental factors, behavioral tendencies, and hormonal disturbances promote venous reflux, valve incompetence, and venous blood stasis. Increased venous hydrostatic pressure and changes in shear-stress cause glycocalyx injury, endothelial dysfunction, secretion of adhesion molecules, leukocyte recruitment/activation, and release of cytokines, chemokines, and hypoxia-inducible factor, causing smooth muscle cell switch from contractile to synthetic proliferative phenotype, imbalance in matrix metalloproteinases (MMPs), degradation of collagen and elastin, and venous tissue remodeling, leading to venous dilation and varicose veins. In the advanced stages of CVD, leukocyte infiltration of the vein wall causes progressive inflammation, fibrosis, disruption of junctional proteins, accumulation of tissue metabolites and reactive oxygen and nitrogen species, and iron deposition, leading to skin changes and venous leg ulcer (VLU). CVD management includes compression stockings, venotonics, and surgical intervention. In addition to its antithrombotic and fibrinolytic properties, literature suggests sulodexide benefits in reducing inflammation, promoting VLU healing, improving endothelial function, exhibiting venotonic properties, and inhibiting MMP-9. Understanding the role of glycocalyx, endothelial dysfunction, and vascular remodeling should help delineate the underlying mechanisms and develop improved biomarkers and targeted therapy for CVD and VLU.

Changes of the serum properties and its effect on the endothelial cells restoration in patients with chronic venous disease treated with sulodexide

OBJECTIVE

Inflammation and endothelial dysfunction are important venous changes in patients with chronic venous disease (CVD). The use of the venoactive drugs remains an important treatment modality for patients with CVD, reducing the severity of the CVD-related symptoms and swelling but also reducing inflammation and protecting endothelial cells. In this research, the effects of the serum obtained from patients with CVD before and after sulodexide treatment were evaluated for in vivo and in vitro inflammatory markers and endothelial cell function.

METHODS

Inflammatory markers (IL-6, matrix metalloproteinase-9 [MMP-9], vascular cell adhesion molecule-1 [VCAM-1], and von Willebrand factor [vWF]) from the incompetent great saphenous veins (GSVs) and from the systemic venous circulation were studied in 10 patients with CVD (C2s) before and after 2 months of sulodexide (2 × 500 lipasemic units/d) therapy. Serum obtained from the vein blood before and after sulodexide treatment was evaluated for in vitro cultured human umbilical vein endothelial cell function.

RESULTS

The serum collected from lower leg incompetent GSVs had significantly elevated levels of VCAM-1 (+29%, P < .001) compared with the serum from the systemic circulation. Endothelial cells exposed to the serum from the incompetent lower leg veins of the untreated CVD patients demonstrated higher stimulated synthesis of MMP-9 (+17%, P < .01), as well as increased markers of senescence (prolongation of population doubling time, β-galactosidase activity, and expression of p21 and p53 genes). CVD serum-induced senescent endothelial cells had a higher expression of genes regulating IL-6, MMP-9, VCAM-1, and vWF synthesis. The overall proinflammatory effect on endothelial cells by the serum collected from the incompetent GSVs was stronger as compared with the serum from the systemic circulation. Serum collected from the veins after sulodexide treatment caused lower levels of endothelial cell inflammatory markers as well as respective gene expression than serum obtained at the beginning of the study (before sulodexide treatment). Sulodexide application also reduced the inflammatory secretory activity of the senescent endothelial cells. Sulodexide treatment resulted in the decrease of the majority of the studied inflammatory parameters in both lower limb incompetent vein and systemic blood.

CONCLUSIONS

In patients with CVD, there are significant differences between circulating inflammatory markers analyzed from the lower leg incompetent GSV segments compared with the systemic circulation, indicating a higher inflammatory condition in CVD. Treatment with sulodexide reduces the proinflammatory and endothelial cell activation properties of the serum from patients with CVD.

CLINICAL RELEVANCE

The study documented the significant proinflammatory human vascular endothelial cell activation when exposed to the serum collected from the varicose veins as compared with the serum from the systemic circulation in patients with chronic venous disease (CVD). The inflammatory marker expression, endothelial dysfunction, and endothelial cell senescence transformation can be successfully controlled and downregulated by patients' exposure to the glycosaminoglycan (sulodexide) treatment. Further studies are needed to confirm if glycosaminoglycan application can prevent further CVD clinical progression due to potential CVD-related pathological processes' modulation and their downregulation.

Association of varicose veins with incidence risk of atrial fibrillation: a population-based cohort study

BACKGROUND

Varicose veins (VV) were once considered benign and common ailments; however, recent research suggests a potential link between VV and cardiovascular diseases or mortality. VV share common risk factors and pathophysiology with cardiovascular disease, potentially influencing the vascular system. Therefore, the authors aimed to investigate the association between VV and the incidence risk of atrial fibrillation (AF) using a population-based cohort.

METHODS

Our retrospective cohort study included 2 680 971 individuals who underwent examination through the Korean National Health Screening Service from 2010 to 2011. VV was defined by two or more claims with the International Classification of Diseases 10th Revision diagnostic codes: I83.0, I83.1, I83.2 (VV of lower extremities with ulcer or inflammation, severe VV), and I83.9 (asymptomatic VV of lower extremities, mild VV). The 1:3 propensity score matching (PSM) was used to assess the risk of newly developed AF, identified via insurance claims coded as I48.

RESULTS

The mean age of all participants was 48.5±14.2 years, with 51.4% being male. Among the population, 24 557 (0.91%) had VV, including 3684 (0.14%) of severe VV and 20 873 (0.77%) of mild VV. During a median follow-up of 10.06 years, 24 557 (0.92%) cases of AF occurred. Participants with VV exhibited an increased incidence risk of AF compared to those without it before (HR: 1.13, 95% CI: 1.06-1.21, P <0.001) and after PSM (HR: 1.17, 95% CI: 1.08-1.27, P <0.001). This positive association was consistently observed in severe VV both before (HR: 1.19, 95% CI [1.09-1.28], P =0.002) and after PSM (HR: 1.20, 95% CI [1.10-1.30], P =0.003) and mild VV also before (HR: 1.10, 95% CI [1.04-1.16], P =0.003) and after PSM (HR: 1.13, 95% CI [1.03-1.-20], P <0.001).

CONCLUSIONS

These findings suggest that VV may be associated with an increased risk of AF. Hence, the presence of VV should be considered as an association factor for AF occurrence.

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.

Morphological study of incompetent saphenous veins: apoptosis and ultrastructural changes of smooth muscle cells

BACKGROUND

Varicose veins affect approximately 25% of people in industrialized countries.

METHODS

The study aimed at detecting apoptotic cells and histopathological changes in varicose vein walls. Patients (N.=41) with varicose veins and 30 control group patients were divided into two groups according to their age (younger and older than 50 years). Apoptosis was determined by the TUNEL assay, elastin and collagen IV expression by immunohistochemistry and ultrastructural changes by transmission electron microscopy.

RESULTS

The results show that the number of apoptotic cells in the layers of varicose veins increased, in particular in a group of patients aged over 50 years. In the varicose veins as compared to control veins the elastic fibers were found to be thinner, more fragmented and disorderly arranged. Elastin and collagen IV expression was found to decline in the intima and the media of varicose veins in both age groups. Electron microscopy demonstrated hypertrophy and degeneration of smooth muscle cells. Furthermore, cells with ultrastructural feature of apoptosis were noted. In the disorganized and expanded extracellular matrix membrane-bound vesicles, ghost bodies with different size and electron density were observed. Ghost bodies seem to bud off from smooth muscle cells and are likely to be involved in extracellular matrix remodeling as they are seen in close contact with collagen fibers.

CONCLUSIONS

The study demonstrates increase of apoptotic cells in the wall of varicose veins along with vein wall structural abnormalities including alterations of smooth muscle cells and decline of elastin and collagen IV expression.

Pathophysiology and Genetic Associations of Varicose Veins: A Narrative Review

Varicose veins (VVs) have a high prevalence worldwide and have become a major medical burden. Their pathophysiology involves a complex interplay of inflammation and tissue remodeling, and current treatment is limited by its impact on the pathophysiological mechanisms. In addition, despite clear environmental factors, family history is an important risk factor, suggesting a genetic component to the risk of developing VVs. Our understanding of the pathogenesis of these diseases has benefited greatly from the expansion of population genetic studies, from pioneering family studies to large genome-wide association studies; we now find multiple risk loci for each venous disease. This review considers the pathophysiology of VVs, highlighting the current state of genetic knowledge. We also propose future directions for research.

Verständnis, Prävention und Behandlung von venösen und lymphatischen Erkrankungen basieren auf der Arbeit von Grundlagenforschern

Zweck Die Rolle der Grundlagenforschung in allen Bereichen der Medizin war, ist und wird auch immer kritisch sein. Die Grundlagenforschung leistet einen Beitrag zu Wissen und Fortschritt. In der Phlebologie ist es nicht anders. Das Manuskript beschreibt die neuesten Errungenschaften der Grundlagenforschung zum Thema Phlebologie.

Methode Der vorliegende Beitrag beleuchtet Publikationen mit dem Thema Grundlagenforschung in der Phlebologie aufgrund einer PubMed-Suche. Die gefundenen Artikel sowie die verschiedenen Schritte, die für Grundlagenforschung angewendet werden, werden diskutiert. Die Relevanz dieser Arbeiten in Bezug auf die tägliche Arbeit in der Phlebologie wird beleuchtet, insbesondere in Bezug auf die Veränderungen der Venenklappen, der Venenwand und den darauffolgenden Störungen des Blutstroms.

Ergebnisse Veränderte Venenwände bei Varizen sind das Ergebnis eines Umbauprozesses aufgrund von Veränderungen der Venenwand auf Zellebene sowie im Interstitium. An diesem Prozess sind glatte Muskelzellen beteiligt. Ferner wurde eine Transformation vom kontraktilen zum sekretorischen Phänotyp beschrieben. In diesem Umbaustadium sind Matrix-Metalloproteinasen (MMP) aktiv beteiligt. Sie tragen zur beobachteten endgültigen Veränderung der Venenwand bei Varizen bei. Die Eigenschaften des Blutstroms und die Funktion der Venenklappen haben sich als zusammenhängendes System erwiesen.

Schlussfolgerungen Die wissenschaftliche Methode ist der Grundpfeiler der Grundlagenforschung. Varizen entstehen durch einen veränderten Blutstrom und einen Umbau der Venenwand.

The aging venous system: from varicosities to vascular cognitive impairment

Aging-induced pathological alterations of the circulatory system play a critical role in morbidity and mortality of older adults. While the importance of cellular and molecular mechanisms of arterial aging for increased cardiovascular risk in older adults is increasingly appreciated, aging processes of veins are much less studied and understood than those of arteries. In this review, age-related cellular and morphological alterations in the venous system are presented. Similarities and dissimilarities between arterial and venous aging are highlighted, and shared molecular mechanisms of arterial and venous aging are considered. The pathogenesis of venous diseases affecting older adults, including varicose veins, chronic venous insufficiency, and deep vein thrombosis, is discussed, and the potential contribution of venous pathologies to the onset of vascular cognitive impairment and neurodegenerative diseases is emphasized. It is our hope that a greater appreciation of the cellular and molecular processes of vascular aging will stimulate further investigation into strategies aimed at preventing or retarding age-related venous pathologies.

Phenotypic and Functional Transformation in Smooth Muscle Cells Derived from a Superficial Thrombophlebitis-affected Vein Wall

BACKGROUND

Superficial thrombophlebitis (ST) is a frequent pathology, but its exact incidence remains to be determined. This study tested the hypothesis whether relationships exist among smooth muscle cells (SMCs) derived from ST, varicose great saphenous veins (VGSVs), and normal great saphenous veins (GSVs).

METHODS

Forty-one samples of ST, VGSVs, and GSVs were collected. SMCs were isolated and cultured. Proliferation, migration, adhesion, and senescence in SMCs from the three vein walls were compared by various methods. Bax, Bcl-2, caspase-3, matrix metalloproteinase-2 (MMP-2), MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1), and TIMP-2 messenger RNA (mRNA) and protein expressions were detected by fluorescence quantitative PCR and Western blot.

RESULTS

An obvious decrease in cytoskeletal filaments was observed in thrombophlebitic vascular smooth muscle cells (TVSMCs). The quantity of proliferation, migration, adhesion, and senescence in TVSMCs was significantly higher than in varicose vascular smooth muscle cells and normal vascular smooth muscle cells (NVSMCs) (all P < 0.05). Bax and caspase-3 mRNA and protein expression were decreased, while Bcl-2 mRNA and protein expression were increased in the TVSMCs compared with the varicose vascular smooth muscle cells and the NVSMCs (all P < 0.05). MMP-2, MMP-9, TIMP-1, and TIMP-2 mRNA and protein expression were significantly increased in the TVSMCs compared with the VVGSVs and the NVSMCs (all P < 0.05).

CONCLUSION

SMCs derived from ST are more dedifferentiated and demonstrate increased cell proliferation, migration, adhesion, and senescence, as well as obviously decreased cytoskeletal filaments. These results suggest that the phenotypic and functional differences could be related to the presence of atrophic and hypertrophic vein segments during the disease course among SMCs derived from ST, VGSVs, and GSVs.

Mechanisms of Lower Extremity Vein Dysfunction in Chronic Venous Disease and Implications in Management of Varicose Veins

Chronic venous disease (CVD) is a common venous disorder of the lower extremities. CVD can be manifested as varicose veins (VVs), with dilated and tortuous veins, dysfunctional valves and venous reflux. If not adequately treated, VVs could progress to chronic venous insufficiency (CVI) and lead to venous leg ulcer (VLU). Predisposing familial and genetic factors have been implicated in CVD. Additional environmental, behavioral and dietary factors including sedentary lifestyle and obesity may also contribute to CVD. Alterations in the mRNA expression, protein levels and proteolytic activity of matrix metalloproteinases (MMPs) have been detected in VVs and VLU. MMP expression/activity can be modulated by venous hydrostatic pressure, hypoxia, tissue metabolites, and inflammation. MMPs in turn increase proteolysis of different protein substrates in the extracellular matrix particularly collagen and elastin, leading to weakening of the vein wall. MMPs could also promote venous dilation by increasing the release of endothelium-derived vasodilators and activating potassium channels, leading to smooth muscle hyperpolarization and relaxation. Depending on VVs severity, management usually includes compression stockings, sclerotherapy and surgical removal. Venotonics have also been promoted to decrease the progression of VVs. Sulodexide has also shown benefits in VLU and CVI, and recent data suggest that it could improve venous smooth muscle contraction. Other lines of treatment including induction of endogenous tissue inhibitors of metalloproteinases (TIMPs) and administration of exogenous synthetic inhibitors of MMPs are being explored, and could provide alternative strategies in the treatment of CVD.

Cellular senescence at the saphenofemoral junction in patients with healthy, primary varicose and recurrent varicose veins - A pilot study

OBJECTIVES

Cellular senescence could play a role in the development of venous disease. Superficial venous reflux at the saphenofemoral junction is a common finding in patients with primary varicose veins. Furthermore, reflux in this essential area is associated with higher clinical stages of the disease and recurrent varicose veins. Therefore, this pilot study aimed to investigate cellular senescence in the immediate area of the saphenofemoral junction in patients with healthy veins, primary varicose veins and additionally in patients with recurrent varicose veins due to a left venous stump.

METHODS

We analyzed vein specimens of the great saphenous vein immediately at the saphenofemoral junction. Healthy veins were collected from patients who underwent arterial bypass reconstructions. Samples with superficial venous reflux derived from patients who received high ligation and stripping or redo-surgery at the groin, respectively. Sections were stained for p53, p21, and p16 as markers for cellular senescence and Ki67 as a proliferation marker.

RESULTS

A total of 30 samples were examined (10 healthy, 10 primary varicose, and 10 recurrent varicose veins). We detected 2.10% p53⁺ nuclei in the healthy vein group, 3.12% in the primary varicose vein group and 1.53% in the recurrent varicose vein group, respectively. These differences were statistically significant (p = 0.021). In the healthy vein group, we found 0.43% p16⁺ nuclei. In the primary varicose vein group, we found 0.34% p16⁺ nuclei, and in the recurrent varicose vein group, we found 0.74% p16⁺ nuclei. At the p < 0.05 level, the three groups tended to be significant without reaching statistical significance (p = 0.085). There was no difference in respect of p21 and Ki67.

CONCLUSION

We found significantly higher expression rates of p53 in primary varicose veins at the saphenofemoral junction than in healthy veins. p16 expression tended to be increased in the recurrent varicose vein group. These preliminary findings indicate that cellular senescence may have an impact in the development of varicose veins or recurrence. Further studies addressing this issue are necessary.

Phenotypic and functional transformation in smooth muscle cells derived from varicose veins

OBJECTIVE

Varicose veins (VVs) are a common disorder of venous dilation and tortuosity, but the underlying mechanism is unclear. The functional integrity and phenotypic differences of VVs are also unclear. This study tested the hypothesis that phenotypic and functional differences exist between smooth muscle cells (SMCs) derived from VVs and normal veins.

METHODS

SMCs were isolated from 28 samples of varicose great saphenous veins (VGSVs) and normal great saphenous (NGSVs) and cultured. Proliferation, migration, adhesion, and aging capacity in SMCs were compared in the two veins. Bas, Bcl-2, caspase-3, matrix metalloproteinase (MMP)-2 MMP-9, tissue inhibitor of metalloproteinases (TIMP)-1, and TIMP-2 messenger (m)RNA expression and protein content were detected by fluorescence quantitative polymerase chain reaction and immunoblotting.

RESULTS

The microfilament structure of the framework was increased in SMCs in the VGSV group. Proliferation, migration, adhesion, and the aging cell count in SMCs in the VGSV group were significantly higher than the corresponding regions in the NGSV group (P < .05). Bas and caspase-3 mRNA expression and protein content were decreased, whereas Bcl-2 mRNA expression and protein content were increased in the VGSV group compared with the NGSV group (P < .05). MMP-2, MMP-9, TIMP-1, and TIMP-2 mRNA expression and protein content in the VGSV group were increased compared with the NGSV group (P < .05).

CONCLUSIONS

SMCs derived from VGSVs are more dedifferentiated and demonstrate increased proliferative and synthetic capacity. These results suggest the presence of phenotypic and functional differences between SMCs derived from VGSVs and NGSVs. The phenotypic and functional abnormalities in SMCs may be associated with the pathogenesis in VGSVs.

Assessment of apoptosis in the native vein used for hemodialysis access

Aim

To determine whether apoptosis is more common in previously punctured native veins than in non-punctured native veins among patients who undergo surgical creation of arteriovenous fistula (AVF) for dialysis access.

Methods

Cephalic vein specimens were obtained from January 1, 2013 to December 31, 2014 from 60 patients, 30 with previously punctured native veins and 30 with non-punctured native veins. Before AVF placement, a 1-cm vein segment was excised from distal part of the vein for histological, histochemical, and immunohistochemical analysis. Vein specimens were divided into two portions along the longitudinal axis and stained with hematoxylin and eosin for routine histological evaluation. Immunohistochemical analysis was used to localize Bax, p53, caspase 3, and Bcl-2 expression.

Results

The group with previously punctured veins showed significantly increased caspase 3 (P < 0.001, two-sided Fisher`s Exact Test) and Bax expression (P = 0.002, two-sided Fisher`s Exact Test) and significantly decreased Bcl-2 expression (P < 0.001, two-sided Fisher`s Exact Test) compared with the control group. There were no significant differences between the groups in p53 expression (χ² = 0.071, df = 1, P = 0.791). Fistula failure was significantly more common in the study group (26.7% vs 6.7%, χ² = 4.32, df = 1, P = 0.038).

Conclusion

Our study indicates a possible role of venipuncture in apoptosis development and a possible role of apoptosis in fistula failure, but we do not have sufficient evidence to conclude that it represents its main cause.

News in Pathogenesis of Chronic Venous Insufficiency

This review article is concentrating on the news in the pathophysiology of chronic venous insufficiency (CVD). Despite ongoing progress in understanding the molecular aspects of CVD the exact mechanism of its development remains unclear. Many different factors may play role in the pathogenesis of CVD, including changes in hydrostatic pressure, valvular incompetence, increased capillary permeability, endothelial dysfunction, activation of leukocytes, deep venous obstruction, capillary microthrombosis, ineffective function of calf muscle pump, biochemical and structural changes in the vessel wall, extracellular matrix alteration, and several other mechanisms. A better understanding of the pathophysiology is an important step in the finding of new potential treatment.

Dysregulated apoptosis of the venous wall in chronic venous disease and portal hypertension

Introduction

The etiology of varicose veins remains elusive. We hypothesized that abnormal cell cycle events in the vein wall may contribute to changes in the structural integrity, thus predisposing to the development of varicosities. The present study was designed to determine whether or not the same molecular apoptotic pathway exists between great saphenous and splenic veins.

Methods

Thirty-six samples of diseased splenic veins and varicose great saphenous veins were collected. Twenty-five samples of control splenic and great saphenous veins were also collected. The apoptotic cell proteins expression was immunohistochemically stained with antibodies (anti-Bax and anti-Bcl-xl). Apoptosis was evaluated by the terminal deoxynucleotidyl transferase-mediated nick-end labeling (TUNEL) assay and immunofluorescence staining. The morphology of apoptotic cells was observed with an electron microscope.

Results

The apoptotic ratio in walls (intima and media) of diseased splenic vein and varicose great saphenous vein groups were significantly lower than the corresponding regions in the splenic vein and great saphenous vein groups ( p < 0.01), respectively. A significant difference was not noted in the ratio change of apoptotic cells between the diseased splenic vein and varicose great saphenous vein groups ( p > 0.05). The high positive expression of Bcl-xl proteins was detected in the diseased splenic vein and varicose great saphenous vein groups, respectively. While the high positive expression of Bax proteins was also observed in the splenic vein and great saphenous vein groups, respectively. Electron microscopic observations confirmed that endothelial and smooth muscle cells in diseased splenic vein, varicose great saphenous vein, splenic vein, and great saphenous vein walls exhibited apoptotic morphologic features, such as fuzzy mitochondrial cristae, medullary changes, and margination of the nuclear chromatin.

Conclusions

Our results showed the same dysregulation of apoptosis via the intrinsic pathway in diseased splenic veins and varicose great saphenous veins. This observational study suggests that apoptotic down-regulation in the veins wall is a cause of diseased splenic veins and varicose great saphenous veins, but does not exclude the possibility that other mechanisms are involved.

Changes in levels of apoptosis in the walls of different segments of great saphenous varicose veins

Objective

Disordered programmed cell death may play a role in the development of superficial venous incompetence. We have determined the number of cells undergoing apoptosis and the alterations in the apoptotic level in the wall of different segments of the great saphenous varicose vein.

Methods

Twenty-one varicose great saphenous veins (VGSVs) (varicose group) and 12 normal great saphenous veins (GSVs) (control group) were collected, and the apoptosis level in the upper, middle, and lower segments were immunohistochemically stained with antibodies (anti-Bax and anti-Bcl-xl). Apoptosis was evaluated by the TUNEL assay and immunofluorescence staining. The morphology of apoptotic cells was observed with an electron microscope.

Results

Quantitative analysis showed that the apoptotic ratios in venous walls (intima and media) of the varicose group were significantly lower than the corresponding regions in the control group (all P < 0.05). A significantly higher apoptotic rates of the venous walls was observed in control group within the upper compared with the lower segment ( P < 0.05). Significantly higher positive proteins expression rates of Bcl-xl/Bax were also detected in the VGSVs compared with the GSVs within the three segments, respectively ( P < 0.01). Electron microscopic observations confirmed that endothelial and smooth muscle cells in varicose and normal vein walls exhibited apoptotic morphologic features, such as fuzzy mitochondrial cristae, medullary changes, and margination of the nuclear chromatin.

Conclusion

VGSV walls were found to have a significant decrease in apoptotic rate compared with that of GSVs. The rate of apoptosis in the intima and media within the upper segment was increased more than the middle and lower segments in the GSVs. Our findings confirm that programmed cell death is down-regulated in primary varicose veins.

Assessment of apoptotic cells in the wall of thrombophlebitic saphenous vein

Introduction

Programmed cell death plays a critical role in various physiological processes. In the present study, we investigated its possible pathogenic role in primary varicose veins. We studied histological changes in surgical specimens from thrombophlebitic saphenous veins. In thrombophlebitic saphenous, varicose, and healthy veins, we also determined the number of apoptotic cells, and investigated apoptosis in the role of the pathogenesis of varicose veins.

Methods

Forty-four specimens of thrombophlebitic saphenous veins and simple varicose veins were collected. Thirteen samples of normal great saphenous veins were also collected (control group). Apoptosis of venous walls was determined by terminal deoxynucleotidyl transferase-mediated nick-end labeling (TUNEL) and immunofluorescence methods. The corpuscular number per high-power field was counted under light microscopy.

Results

A significantly higher apoptotic ratio of the intima and media were observed in control veins as compared with thrombophlebitic saphenous veins and simple varicose veins ( p < 0.01). A significant difference was not observed between thrombophlebitic saphenous veins and simple varicose veins ( p > 0.05). A significant difference was not seen between the intima and media of the three groups ( p > 0.05).

Conclusion

In the walls of thrombophlebitic saphenous veins and varicose veins, the apoptotic indices were clearly decreased. The results suggest that the process of programmed cell death was inhibited in walls of thrombophlebitic saphenous veins and varicose veins.

Biomolecular mechanisms in varicose veins development

Varicose veins (VVs) can be described as tortuous and dilated palpable veins, which are more than 3 mm in diameter. They are one of the clinical presentations of chronic venous disorders, which are a significant cause of morbidity. The prevalence of VVs has been estimated at 25-33% in women and 10-20% in men and is still increasing at an alarming rate. Family history, older age, female, pregnancy, obesity, standing occupations, and a history of deep venous thrombosis are the predominant risk factors. A great amount of factors are implicated in the pathogenesis of VVs, including changes in hydrostatic pressure, valvular incompetence, deep venous obstruction, ineffective function of calf muscle pump, biochemical and structural alterations of the vessel wall, extracellular matrix abnormalities, impaired balance between growth factors or cytokines, genetic alterations, and several other mechanisms. Nevertheless, the issue of pathogenesis in VVs is still not completely known, even if a great progress has been made in understanding their molecular basis. This kind of studies appears promising and should be encouraged, and perhaps the new insight in this matter may result in targeted therapy or possibly prevention.

Finite Element simulation of buckling-induced vein tortuosity and influence of the wall constitutive properties

The mechanisms giving rise to vein tortuosity, which is often associated with varicosis, are poorly understood. Recent works suggest that significant biological changes in the wall of varicose veins may precede the mechanical aspects of the disease. To test the hypothesis of tortuosity being a consequence of these changes, a Finite Element model was developed based on previous experimental work on vein buckling. The model was then used to evaluate the effect of alterations of the mechanical behavior of the wall on tortuosity onset and severity. The results showed that increasing anisotropy toward the circumferential direction promotes tortuosity. An increase in wall stiffness tends to decrease the level of tortuosity but interestingly, if the vein segment is little or not pre-stretched such increase will not prevent, or it will even promote, the onset of tortuosity. These results provide additional arguments supporting the hypothesis of tortuosity being the consequence of biologically-induced changes in the varicose vein wall. Based on a 3D model of the leg and in vivo identification of the material properties of varicose veins, a clinical validation of these findings is being developed.

Associations of NF-kappaB and bax with apoptosis in varicose veins of women of different age groups

The study aimed at detecting apoptotic endothelial cells (ECs) and smooth muscle cells (SMCs) together with determining expression of NF-kappaB (p105/p50) and Bax in varicose vein walls. Women (n = 35) undergoing the excision of varicose veins were divided into 3 groups: younger than 35 years (I), 36–50 years (II), and older than 50 years (III). Apoptosis was determined by the TUNEL method, NF-kappaB and Bax expression by immunohistochemistry. The percentage of apoptotic ECs and SMCs in the layers of varicose vein wall increased in groups II and III. NF-kappaB expression had the lowest level in Group II with particularly low level in the media. Contrariwise, Bax expression levels in Group II were increased. The study revealed that in varicose veins ECs and SMCs apoptosis increased with advancing age. If increase in apoptosis during earlier stages of varicosities is probably regulated by intrinsic pathway, then in older patients other signaling pathways may be involved.

Desmuslin gene knockdown causes altered expression of phenotype markers and differentiation of saphenous vein smooth muscle cells

OBJECTIVE

Phenotypic alterations of vascular smooth muscle cells (VSMCs) appear critical to the development of primary varicose veins. Previous study indicated desmuslin, an intermediate filament protein, was differentially expressed in smooth muscle cells (SMCs) isolated from varicose veins; thus, it was naturally hypothesized that altered desmuslin expression might in turn affect the functioning of VSMCs, leading to the phenotypic alterations and varicose vein development.

METHODS

In this study, expression of desmuslin in normal human saphenous vein SMCs was knocked down using small interfering RNA (siRNA), and control cells were treated with a scrambled siRNA sequence. The levels of several phenotypic markers including smooth muscle (SM) alpha-actin and smooth muscle myosin heavy chain (SM-MHC) were assessed. Collagen formation, matrix metalloproteinase expression (MMP-2), and cytoskeletal and morphological changes were also examined.

RESULTS

SMCs treated with desmuslin siRNA exhibited significantly increased levels of collagen synthesis and MMP-2 expression and decreased expression levels of SM alpha-actin, SM-MHC, and smoothelin and exhibited disassembly of actin stress fibers when compared with the control cells. Changes in cell morphology and actin fiber networks in VSMCs treated with desmuslin siRNA were consistent with a lower degree of differentiation.

CONCLUSIONS

These results indicated desmuslin expression is required for the maintenance of VSMC phenotype. Decreased desmuslin expression may affect differentiation of VSMCs and ultimately contribute to the development of varicose veins.

Involved intrinsic apoptotic pathway in the varicocele and varicose veins

BACKGROUND

Disordered programmed cell death may play a role in the development of venous diseases. Tissue hypoxia caused by blood stagnation and venous hypertension is the similar etiology of varicocele and varicose veins. We studied the vascular histopathology and determined whether there is the same apoptotic pathway in both venous diseases.

METHODS

The study groups consisted of 1-cm venous segments obtained from 10 patients during vascular stripping surgery for varicose saphenous vein and 1 cm of internal spermatic veins obtained from 12 patients during left varicocele repair. The control samples of 1 cm internal spermatic vein were obtained from 10 male patients who underwent left inguinal herniorrhaphy. The three layers of vascular histology were measured and compared by Masson trichrome stain, and the apoptotic proteins including Bcl-2, Fas, cleaved caspase-9, cleaved caspase-8, and cleaved caspase-3 were detected. Data were analyzed using the one-way analysis of variance with Tukey's comparison test.

RESULTS

The relative thickness of intima and adventitia layer was smaller in both study groups than in the control group. But a significant hypertrophy of media layer was observed in the varicocele and varicose veins than in the control group (p < 0.05). Overexpression of Bcl-2 and decreased expressions of cleaved caspase-9 and cleaved caspase-3 was observed in both study groups. There is no statistical difference in Fas and cleaved caspase-8 expressions in the control and study groups.

CONCLUSION

Our data showed vascular smooth muscle hypertrophy in the diseased vessels. The same dysregulation of apoptosis through intrinsic pathway was demonstrated in varicocele and varicose veins under tissues hypoxia. This mechanism of reduced apoptosis might contribute to the dilated and thickened walls of both venous diseases.

Pathogenesis of primary varicose veins

BACKGROUND

Valvular incompetence and reflux are common features of primary varicose veins, and have long been thought to be their cause. Recent evidence, however, suggests that changes in the vein wall may precede valvular dysfunction.

METHODS

A literature search was performed using PubMed and Ovid using the keywords 'varicose vein wall changes', 'pathogenesis', 'aetiology' and 'valvular dysfunction'. Articles discussing the pathophysiology of complications of varicose veins, such as ulceration, recurrence, thrombophlebitis and lipodermatosclerosis, were excluded.

RESULTS AND CONCLUSION

Positive family history, age, sex and pregnancy are important risk factors for varicose vein formation. Areas of intimal hyperplasia and smooth muscle cell proliferation are often noted in varicose veins, although regions of atrophy are also present. The total elastin content in varicose as opposed to non-varicose veins is reduced; changes in overall collagen content are uncertain. Matrix metalloproteinases (MMPs), including MMP-1, MMP-2, MMP-3, MMP-7 and MMP-9, and tissue inhibitor of metalloproteinase (TIMP) 1 and TIMP-3 are upregulated in varicose veins. Activation of the endothelium stimulates the recruitment of leucocytes and the release of growth factors, leading to smooth muscle cell proliferation and migration. Dysregulated apoptosis has also been demonstrated in varicose veins. An understanding of the pathophysiology of varicose veins is important in the identification of potential therapeutic targets and treatment strategies.

In vitro differences between smooth muscle cells derived from varicose veins and normal veins

OBJECTIVE

The theory of primary venous dilatation leading to secondary valvular incompetence and varicose vein formation has received more attention nowadays. Although many studies have investigated the role of the main components of the venous wall in the development of varicose veins, the leading cause remains unknown. The present study was designed to establish the role of smooth muscle cells (SMCs) of the tunica media on the pathogenesis of varicose veins by analyzing the phenotypic and functional differences between SMCs derived from varicose veins and normal veins.

METHODS

SMCs were isolated and cultured from saphenous veins of patients with varicose veins and normal veins. Cell proliferation and migration rates were compared. Expression of phenotype-dependent markers and matrix metalloproteinase-2 (MMP) production were analyzed by immunoblotting. Total collagen synthesis was evaluated by measuring the radioactivity of L-[3, 4-(3)H]proline in the media and the cell layer.

RESULTS

SMCs derived from varicose veins demonstrated increased proliferation (2-fold, P < .01), migration (3-fold, P < .001), MMP-2 production (3-fold, P < .01), and collagen synthesis (>2-fold, P < .001), with decreased expression of phenotype-dependent markers compared with SMCs derived from normal veins (P < .05).

CONCLUSION

SMCs derived from varicose veins are more dedifferentiated and demonstrate increased proliferative and synthetic capacity than SMCs derived from normal veins. These properties may contribute to the remodeling of the venous wall and the weakening of its antipressure capacity.

Association of primary varicose veins with dysregulated vein wall apoptosis

BACKGROUND

Disordered programmed cell death may play a role in the development of superficial venous incompetence. We have determined the number of cells in apoptosis, and the mediators regulating the intrinsic and extrinsic pathways in specimens of varicose vein.

METHODS

Venous segments were obtained from 46 patients undergoing surgical treatment for primary varicose veins. Controls samples were obtained from 20 patients undergoing distal arterial bypass grafting surgery. Segments of the distal and proximal saphenous trunk as well as tributaries were studied. Cell apoptoses and mediators of the mitochondrial and trans membrane pathway were evaluated with peroxidase in situ apoptosis detection, Bax and Fas detection, caspase-9 and 8 detection in the medial layer.

RESULTS

Disorganised histological architecture was observed in varicose veins. Primary varicose veins also contained fewer peroxidase in situ-positive cells than control veins (2.6% S.D. 0.2% versus 12% S.D. 0.93%, P=.0001, Mann-Whitney u test), fewer Bax positive cells (2.1.% S.D. 0.3% versus 13% S.D. 0.9%, P=.0001) and fewer Caspase 9 positive cells (3.2% S.D. 1% versus 12% S.D. 1.3%, P=.0001). Similar findings were observed in saphenous trunk, main tributaries and accessory veins. In patients with recurrent varicose veins in whom the saphenous trunk had been preserved showed similar findings to primary varicose veins. Residual varicose veins contained fewer peroxidase in situ-positive cells than healthy veins (3.2% S.D. 0.6% versus 11% S.D. 2%, P=.0001), fewer Bax positive cells (2.2% S.D. 0.3% versus 12% S.D. 0.7%, P=.0001) and fewer Caspase 9 positive cells (2.6% S.D. 0.6% versus 12% S.D. 1%, P=.0001). Immunohistochemical detection for Fas and caspase 8 remained equal was the same in the varicose vein and control groups.

CONCLUSION

Apoptosis is down regulated in the medial layer of varicose veins. This dysregulation is attributable to a disorder of the intrinsic pathway and involves the great saphenous vein trunk, major tributaries and accessory veins. This process may be among the causes of primary varicose veins.

Light-Assisted Stab Phlebectomy: Early Postoperative Experience

Light-assisted stab phlebectomy (LASP) is a technique that we have developed for treatment of lower extremity varicose veins. It combines powered and stab phlebectomy with minimally invasive surgical instruments to optimize intraoperative visualization of varicose veins and to remove branch veins with minimal bruising, hematoma, or pain. The early experience with this technique has not been reported. We conducted a retrospective review of all patients who underwent LASP to characterize the associated perioperative experience and to identify postoperative factors that indicated a successful outcome. From 2004 to 2006, LASP was performed on 268 limbs to remove lower extremity branch veins. The majority of patients were women (75%), and the mean age was 52 years. A group of 184 patients underwent LASP in combination with another procedure, and 49 patients underwent LASP alone. Nearly all patients had conscious sedation for anesthesia (99%); operating room time averaged 44 minutes, and blood loss averaged 88 cc. Immediate postoperative complications were infrequent, occurring in 10 per cent of patients, and included unresected or missed veins, hematoma, and cellulitis. LASP provides improved visualization of branch veins and allows varicose veins to be removed with a short operating room time and minor postoperative complications.

Identification of differentially expressed genes in human varicose veins: involvement of matrix gla protein in extracellular matrix remodeling

This study was designed to identify the global pattern of differentially expressed genes in human varicose veins. Using suppressive subtractive hybridization, we identified overexpression of genes known to be associated with extracellular matrix remodeling, including collagen III, tissue inhibitor of metalloproteinases I, dermatopontin, matrix Gla protein (MGP) and tenascin C. Real-time polymerase chain reaction analysis confirmed the differential expression of these genes. The overexpression of MGP transcript was associated with increased MGP level in varicose veins, in particular the undercarboxylated form of the protein. Smooth muscle cells from varicose veins showed increased proliferation rate and enhanced matrix mineralization. This observation correlated with the presence of ectopic mineralization areas in the varicose vein walls. The use of warfarin, to inhibit MGP activity, or siRNA targeting MGP transcript induced a reduction in the exacerbated proliferation of varicose vein smooth muscle cells. Our results suggest that high expression of MGP in varicose veins may contribute to venous wall remodeling by affecting proliferation and mineralization processes probably through impaired carboxylation of MGP. In addition, suppressive subtractive hybridization results also produce a profile of differentially expressed genes in varicose veins, in particular extracellular matrix components. Further study of these genes will provide insights into their specific roles in the etiology of venous disease.

Contrasting Effects of Varicose Vein Surgery on Endothelial-dependent and -independent Cutaneous Vasodilation in the Perimalleolar Region

OBJECTIVES

To evaluate the effects of varicose vein surgery on cutaneous microvascular perfusion and vasodilator responses to acetylcholine (Ach) and sodium nitroprusside (SNP) in the gaiter area of patients with great saphenous vein insufficiency.

METHODS

Twenty-nine patients with isolated great saphenous vein incompetence attended three study mornings (before surgery, and 6-8 weeks and 6 months after sapheno-femoral ligation+partial stripping) during which cutaneous microvascular responses were measured in the supine and standing positions using laser Doppler fluximetry (LDF) combined with incremental-dose iontophoretic administration of endothelial-dependent (Ach) and -independent (SNP) vasodilators.

RESULTS

Varicose vein surgery had no significant effect on baseline cutaneous perfusion or the microvascular response to Ach: e.g. peak vasodilator responses to the 1000 microC stimulus were mean 58 SEM 7, 64 SEM 6 and 65 SEM 7PU on the pre-operative, 6-8 weeks and 6 months assessments. In contrast, the corresponding responses to SNP were significantly increased following surgery: e.g. at 2000 microC, mean 63 SEM 9, 142 SEM 4 and 157 SEM 9PU (p<0.0001) in the upright position.

CONCLUSIONS

Sapheno-femoral ligation and partial stripping in patients with great saphenous vein insufficiency improves endothelial-independent cutaneous vasodilator function at the gaiter area, which may at least partly explain the benefits of surgery in reducing the risk of venous ulceration.

Overexpression of transforming growth factor-beta1 correlates with increased synthesis of nitric oxide synthase in varicose veins

INTRODUCTION

Transforming growth factor-beta 1 (TGF-beta 1 ) is known to maintain a balance between apoptosis and cellular dysfunction and therefore may have a pivotal role in vessel remodeling during pathogenesis of vascular disorders. We previously demonstrated that inducible nitric oxide synthase (iNOS) mediates signal transduction in vascular wall during the development of varicose veins. Currently, we investigated the expression and correlation of TGF-beta 1 , iNOS, monocyte/macrophage infiltration, and loss of vascular smooth muscle cells (VSMCs), in a series of normal and varicose vein specimens.

METHODS

Twenty varicose vein specimens were retrieved from 20 patients undergoing lower-extremity varicose vein excision, and 27 normal greater saphenous vein segments (controls) were obtained from 27 patients undergoing infrainguinal arterial bypass surgery. Principal risk factors (diabetes mellitus, hypertension, tobacco abuse) were also compared. Varicose vein segments were separated into tortuous and nontortuous regions based on their macroscopic and microscopic morphology. VSMC actin, CD68 + monocytes/macrophages, iNOS, and TGF-beta 1 , were examined by immunohistochemistry, immunoblotting, and real-time reverse transcriptase polymerase chain reaction.

RESULTS

According to the CEAP classification for chronic lower extremity venous disease, most of the patients were in class 2 for clinical signs of the disease (n = 11). Mean ages were 53.6 +/- 4.7 years for the varicose vein group and 56.5 +/- 4.4 years for the controls. The gender distribution was same in both groups. Immunoreactivity to TGF-beta 1 and iNOS was significantly different in the tortuous regions of the varicose veins compared with nontortuous regions (P < .01). Not only was a significantly higher expression of iNOS noted in the varicose vein group (P < .001), but a differential expression of iNOS was also observed in the tortuous and nontortuous portions of the varicose veins. Significant overexpression of TGF-beta 1 (P < .01) that correlated with overproduction of iNOS and with increased presence of CD68 + monocytes/macrophages was observed in the varicose vein walls compared with normal veins.

CONCLUSIONS

This is the first evidence of TGF-beta 1 , as well as iNOS, being differentially upregulated in nontortuous and tortuous segments of varicose veins. The increased expression of TGF-beta 1 and presence of macrophages, correlating with overproduction of iNOS, may be associated with varicosity development and deserves further study.

CLINICAL RELEVANCE

The pathogenesis of varicose veins, the most common manifestation of chronic venous disease, is debatable. Elucidation of mechanisms involved in the disease process is the first step to improved therapeutic modulations. Towards this goal, the relationship between NO production and TGF-beta 1 in the molecular pathophysiology of chronic venous disease was investigated. The data identify for the first time, an important role for TGF-b1-iNOS-monocyte/macrophage signaling in the etiology of varicosities. Furthermore, we determine if there are any significant differences within the varicose vein group itself based on regional differences, by classifying the varicose tissues into tortuous and non-tortuous segments.