Endothelial function impairment in chronic venous insufficiency: effect of some cardiovascular protectant agents

Effectiveness of herbal drug Terminalia Arjuna in chronic venous insufficiency - A prospective observational study

INTRODUCTION

Chronic venous insufficiency (CVI) manifests in various clinical presentations ranging from asymptomatic but cosmetic problems to severe symptoms, such as lower limb edema, skin trophic changes, and ulceration. CVI substantially affects the quality of life and work productivity of the patients. Ayurveda, an ancient traditional medicine in India, evaluates the various pathological stages of CVI with a wide range of pathological conditions such as Siragranthi (venous abnormalities), Raktavaritavāta (disorders of vāta occluded by rakta ∼ blood), ApanaVaigunya (vitiated apānavāyu), Arsha (hemorrhoids), VataRakta (rheumatism due to rakta), Kushtha (integumentary disease) and Dushta Vrana (putrefied wound) depending upon the presentations of the patient. Ayurvedic texts mention Terminalia arjuna as a potential herb for treating various conditions related to the circulatory system. The drug is an effective anti-inflammatory, anti-oxidant, and anti-hypertensive and has a definite role in improving cardiovascular hemodynamics and wound healing. These attributes suggest that the potential of Terminalia arjuna needs to be explored as a promising venoactive drug.

METHODS

This prospective observational study included 25 patients (31 limbs) with CVI who were treated with Tab Terminalia arjuna (Bark extract of Terminalia arjuna in a dose of 500 mg, given twice a day) and were observed on two visits on day 30 and day 90. Follow-up was carried out for three months to evaluate post-treatment complications or adverse effects. The clinical outcome assessment was done using Venous Clinical Severity Score (VCSS), and clinical grading was performed using clinical classification (C0 - C6) of CEAP (Clinical-Etiology-Anatomy-Pathophysiology) classification.

RESULTS

The median VCSS score (of both limbs) during the third visit was comparatively lower than the first, with a statistically significant improvement at 0.05 level. Further, there was a substantial positive improvement in the clinical classification of CEAP among the patients in pre and post treatment phase.

CONCLUSION

The prospective observational study shows that Tab Terminalia arjuna is safe and effective in CVI, reducing the symptoms like pain, edema, inflammation, pigmentation, induration and also expediting ulcer healing.

Vena cava presents endothelial dysfunction prior to thoracic aorta in heart failure: the pivotal role of nNOS uncoupling/oxidative stress

Arterial endothelial dysfunction has been extensively studied in heart failure (HF). However, little is known about the adjustments shown by the venous system in this condition. Considering that inferior vena cava (VC) tone could influence cardiac performance and HF prognosis, the aim of the present study was to assess the VC and thoracic aorta (TA) endothelial function of HF-post-myocardial infarction (MI) rats, comparing both endothelial responses and signaling pathways developed. Vascular reactivity of TA and VC from HF post-MI and sham operated (SO) rats was assessed with a wire myograph, 4 weeks after coronary artery occlusion surgery. Nitric oxide (NO), H2O2 production and oxidative stress were evaluated in situ with fluorescent probes, while protein expression and dimer/monomer ratio was assessed by Western blot. VC from HF rats presented endothelial dysfunction, while TA exhibited higher acetylcholine (ACh)-induced vasodilation when compared with vessels from SO rats. TA exhibited increased ACh-induced NO production due to a higher coupling of endothelial and neuronal NO synthases isoforms (eNOS, nNOS), and enhanced expression of antioxidant enzymes. These adjustments, however, were absent in VC of HF post-MI rats, which exhibited uncoupled nNOS, oxidative stress and higher H2O2 bioavailability. Altogether, the present study suggests a differential regulation of endothelial function between VC and TA of HF post-MI rats, most likely due to nNOS uncoupling and compromised antioxidant defense.

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.

Relationship between the drainage pattern of the dural venous sinuses and hearing recovery in patients with sudden sensorineural hearing loss

Although cochlear venous insufficiency has been considered to cause sudden sensorineural hearing loss (SSHL), there is insufficient clinical evidence to support this hypothesis. We sought to determine whether there is a correlation between draining patterns of the dural venous sinuses and the side of the affected ear in SSHL, as well as hearing recovery. The medical records of 109 patients diagnosed with unilateral SSHL were retrospectively reviewed. Magnetic resonance images and pure tone audiometry were performed in all patients. We measured the dominance of the inferior petrosal sinus (IPS) and transverse-sigmoid sinus (TS/SS) ipsilateral to the affected ear. Most patients were characterized by asymmetric venous drainage (IPS, 53.2%; TS/SS, 81.7%). The dominant side of the IPS or TS/SS was independent of the side of the affected ear for all patients in this study. However, in 35 patients with early recovery within 2 weeks, the dominant side of TS/SS was significantly associated with the side of the affected ear (p = 0.011). Moreover, the dominance of both the IPS and TS/SS influenced hearing outcomes at 3 months. Dominant TS/SS ipsilateral to the affected ear, particularly in the presence of ipsilateral hypoplastic IPS, is associated with a favorable hearing prognosis of SSHL.

β-escin selectively targets the glioblastoma-initiating cell population and reduces cell viability

Glioblastoma multiforme (GBM) is a highly aggressive tumour of the central nervous system and is associated with an extremely poor prognosis. Within GBM exists a subpopulation of cells, glioblastoma-initiating cells (GIC), which possess the characteristics of progenitor cells, have the ability to initiate tumour growth and resist to current treatment strategies. We aimed at identifying novel specific inhibitors of GIC expansion through use of a large-scale chemical screen of approved small molecules. Here, we report the identification of the natural compound β-escin as a selective inhibitor of GIC viability. Indeed, β-escin was significantly cytotoxic in nine patient-derived GIC, whilst exhibiting no substantial effect on the other human cancer or control cell lines tested. In addition, β-escin was more effective at reducing GIC growth than current clinically used cytotoxic agents. We further show that β-escin triggers caspase-dependent cell death combined with a loss of stemness properties. However, blocking apoptosis could not rescue the β-escin-induced reduction in sphere formation or stemness marker activity, indicating that β-escin directly modifies the stem identity of GIC, independent of the induction of cell death. Thus, this study has repositioned β-escin as a promising potential candidate to selectively target the aggressive population of initiating cells within GBM.

Plasma concentration of selected biochemical markers of endothelial dysfunction in women with various severity of chronic venous insufficiency (CVI)-A pilot study

BACKGROUND

Although the endothelial dysfunction is considered to be implicated in the pathogenesis of chronic venous insufficiency (CVI) the endothelial status in patients with venous disorders is still not fully evaluated. Therefore the aim of the study was to measure the concentration of selected markers of endothelial dysfunction: von Willebrand factor (vWf), soluble P-selectin (sP-selectin), soluble thrombomodulin (sTM) and soluble VE-cadherin (sVE-cadherin) in CVI women who constitute the most numerous group of patients suffering from venous disease.

MATERIALS AND METHODS

Forty four women with CVI were involved in the study and divided into subgroups based on CEAP classification. Concentration of vWf, sP-selectin, sTM and sVE-cadherin were measured and compared with those obtained in 25 healthy age and sex-matched women.

RESULTS

It was found that the concentration of sTM increased and sVEcadherin decreased along with disease severity in CVI women. A significant rise of sTM was observed especially in CVI women, with the highest inflammation status reflected by hsCRP or elastase concentration, and in CVI women with a high oxidative stress manifested by an increased plasma MDA. A significant fall of circulating sVE-cadherin was reported in CVI women with moderate to highest intensity of inflammation and oxidative stress. There was no change in vWF and sP-selectin concentration at any stage of CVI severity.

CONCLUSIONS

The results of the present study demonstrate the presence of endothelial dysfunction in women suffering from CVI which seems to progress with the disease severity and may be associated with inflammation and enhanced oxidative stress.

Rac1 Pharmacological Inhibition Rescues Human Endothelial Dysfunction

Background

Endothelial dysfunction contributes significantly to the development of vascular diseases. However, a therapy able to reduce this derangement still needs to be identified. We evaluated the effects of pharmacological inhibition of Rac1, a small GTPase protein promoting oxidative stress, in human endothelial dysfunction.

Methods and Results

We performed vascular reactivity studies to test the effects of NSC23766, a Rac1 inhibitor, on endothelium‐dependent vasorelaxation of saphenous vein segments collected from 85 subjects who had undergone surgery for venous insufficiency and from 11 patients who had undergone peripheral vascular surgery. The endothelium‐dependent vasorelaxation of the varicose segments of saphenous veins collected from patients with venous insufficiency was markedly impaired and was also significantly lower than that observed in control nonvaricose vein tracts from the same veins. Rac1 activity, reactive oxygen species levels, and reduced nicotine adenine dinucleotide phosphate (NADPH) oxidase activity were significantly increased in varicose veins, and NSC23766 was able to significantly improve endothelium‐dependent vasorelaxation of dysfunctional saphenous vein portions in a nitric oxide–dependent manner. These effects were paralleled by a significant reduction of NADPH oxidase activity and activation of endothelial nitric oxide synthase. Finally, we further corroborated this data by demonstrating that Rac1 inhibition significantly improves venous endothelial function and reduces NADPH oxidase activity in saphenous vein grafts harvested from patients with vascular diseases undergoing peripheral bypass surgery.

Conclusions

Rac1 pharmacological inhibition rescues endothelial function and reduces oxidative stress in dysfunctional veins. Rac1 inhibition may represent a potential therapeutic intervention to reduce human endothelial dysfunction and subsequently vascular diseases in various clinical settings.

Chronic Venous Disease and Comorbidities

We report the relations between comorbidities and chronic venous disease. In this cross-sectional study, information was gathered from 1679 Serbian patients. The majority (65.0%) of patients were women. Mild forms of chronic venous disease (clinical, etiologic, anatomic and pathophysiologic [CEAP] classification; C0s-C1) were more frequent in women (11.6%), while severe forms (CEAP C4-C6) were more commonly encountered in men (42.1%). The most frequent comorbidity was emphysema/chronic obstructive pulmonary disease in both groups (74.3% in males and 70.6% in females). For females, diabetes mellitus ( P < .005), arterial hypertension ( P < .000), and skeletal/joint diseases ( P < .042) were more commonly found in the C4 to C6 category. Both males and females, with severe form of chronic venous disease, may benefit from additional screening for comorbidities. Further studies are needed to clarify the nature of association among comorbidities and chronic venous disease.

Effect of fluid shear stress on portal vein remodeling in a rat model of portal hypertension

Aims. To explore the effects and mechanisms of fluid shear stress on portal vein remodeling in a rat model of portal hypertension. Methods. Subcutaneous injections of CCl4 were given to establish a rat model of liver cirrhosis and portal hypertension. Biomechanical technology was adopted to determine the dynamic changes of haemodynamic indices and fluid shear stress. Nitric oxide (NO), synthase (NOS), and endothelin-1 (ET-1) of the portal vein blood were measured. Changes in geometric structure and ultrastructure of the portal vein were observed using optical and electron microscopy. Results. After the CC14 injections, rat haemodynamics were notably altered. From week 4 onwards, PVP, PVF, and PVR gradually and significantly increased (P < 0.05 versus baseline). The fluid shear stress declined from week 4 onwards (P < 0.01 versus control group). NO, NOS, and ET-1 increased after repeated CCI4 injections. Hematoxylin and eosin staining showed thickened portal vein walls, with increased inside and outside diameters. Electron microscopy revealed different degrees of endothelial cell degeneration, destruction of basement membrane integrity, proliferating, and hypertrophic smooth muscle cells. Conclusions. Fluid shear stress not only influenced the biomechanical environment of the portal vein but also participated in vascular remodeling.

Cellular and molecular basis of Venous insufficiency

Chronic venous disease (CVD) has a range of clinical presentations, including tortuous, distended veins in lower extremities, increasing skin pigmentation, and in severe cases ulceration of the affected skin. Venous insufficiency, a precursor to CVD characterized by improper return of blood from the lower extremities to the heart, must be studied in its earliest stages at a time when preventative measures could be applied in man. This underscores the need for basic research into biomarkers and genetic predisposing factors affecting the progression of venous disease. Investigation over the past decade has yielded insight into these specific genetic, cellular and molecular mechanisms underlying the development of venous disease. Among the many advances include the elucidation of an increasing role for matrix metalloproteinases as important mediators of the degenerative process involved with venous insufficiency. This may be preceded by an inflammatory process which further contributes to venular degeneration and endothelial dysfunction seen in advanced presentation of disease. Furthermore, genomic analyses have shed light upon temporal expression patterns of matrix remodeling proteins in diseased tissue samples. In this review we examine some of the current findings surrounding cellular, molecular and genetic advances in delineating the etiology of chronic venous disease.

Can calcium dobesilate be used safely for peripheral microvasculopathies that require neoangiogenesis?

Background

Calcium dobesilate (CaD) is a member of the synthetic veno-active drug family. Only a small number of reports are available that describe the micro-angiogenic effects of CaD in the current literature.

Material/Methods

The antiangiogenic potential of CaD was compared with bevacizumab (Bb), which is a potent angiogenesis inhibitor, in a chick chorioallantoic membrane model. Four different concentrations (10⁻⁷, 10⁻⁶, 10⁻⁵, and 10⁻⁴ M) of drug pellet were prepared for each drug. Changes in vessel formation were scored and compared for each drug according to the previous literature.

Result

The antiangiogenic behavior of CaD was lower than Bb, despite the significant dose-dependent manner of escalation. The anti-angiogenic scores of CaD were determined as 0.20, 0.47, 0.66, 1.0 in 10⁻⁷, 10⁻⁶, 10⁻⁵, and 10⁻⁴ M concentrations, respectively (average score >0.5 was significant).

Conclusions

According to the data obtained, this agent should be used carefully for cases in which angiogenesis plays an important role in healing.

Morphological characteristics of the walls of thrombophlebitic saphenous vein

Introduction: To investigate the morphological changes in the walls of thrombophlebitic saphenous veins.

Methods: Fifty-four specimens were made into slices for haematoxylin and eosin and Masson trichrome staining; ultrathin slices were also created. Slices were observed under light microscopy and electron microscopy.

Results: Under light microscopy, the tunica intima of venous wall in the thrombophlebitic saphenous veins group was obviously thickened and incomplete; intravascular papillary endothelial hyperplasia was observed. Hyperplasia of collagenous fibres in the tunica media was observed. Elastic fibres in the tunica externa became fewer, whereas nourishing vessels were significantly increased in number. Infiltration of many inflammatory cells was observed. Under electron microscopy, Auer bodies with high electron density and round granules could be seen in endothelial cells in the thrombophlebitic saphenous veins group. Smooth muscle cells had an irregular karyotype, with blurred cristae in some mitochondria. Myofilaments basically disappeared.

Conclusion: Thrombus formation might aggravate re-modelling of the walls of varicose veins.

Endothelial cells obtained from patients affected by chronic venous disease exhibit a pro-inflammatory phenotype

Background

The inflammatory properties of vein endothelium in relation to chronic venous disease (CVD) have been poorly investigated. Therefore, new insights on the characteristics of large vein endothelium would increase our knowledge of large vessel physiopathology.

Methodology/Principal Findings

Surgical specimens of veins were obtained from the tertiary venous network (R3) and/or saphenous vein (SF) of patients affected by CVD and from control individuals. Highly purified venous endothelial cell (VEC) cultures obtained from CVD patients were characterized for morphological, phenotypic and functional properties compared to control VEC. An increase of CD31/PECAM-1, CD146 and ICAM-1 surface levels was documented at flow cytometry in pathological VEC with respect to normal controls. Of note, the strongest expression of these pro-inflammatory markers was observed in VEC obtained from patients with more advanced disease. Similarly, spontaneous cell proliferation and resistance to starvation was higher in pathological than in normal VEC, while the migratory response of VEC showed an opposite trend, being significantly lower in VEC obtained from pathological specimens. In addition, in keeping with a higher baseline transcriptional activity of NF-kB, the release of the pro-inflammatory cytokines osteoprotegerin (OPG) and vascular endothelial growth factor (VEGF) was higher in pathological VEC cultures with respect to control VEC. Interestingly, there was a systemic correlation to these in vitro data, as demonstrated by higher serum OPG and VEGF levels in CVD patients with respect to normal healthy controls.

Conclusion/Significance

Taken together, these data indicate that large vein endothelial cells obtained from CVD patients exhibit a pro-inflammatory phenotype, which might significantly contribute to systemic inflammation in CVD patients.