Sulodexide Inhibits Arterial Contraction via the Endothelium-Dependent Nitric Oxide Pathway

Background/Objectives: Sulodexide (SDX) is a drug known for restoring the glycocalyx, thereby offering endothelial protection and regulating permeability. Additionally, it has antithrombotic and anti-inflammatory properties and has shown arterial vasodilatory effects. Endothelial cells play a crucial role in maintaining homeostasis, with their dysfunction being a key contributor to loss in vasodilatory response, especially in arterial pathologies. The aim of this study was to investigate the effects of SDX on stimulated vascular tonus in human arterial samples and to assess the function of the endothelial layer as a source of nitric oxide (NO). Methods: A total of 16 internal mammary artery remnants from coronary artery bypass graft surgeries were dissected into endothelium-intact and endothelium-denuded groups (n = 8 each). The arterial rings were equilibrated under tension, with their basal tonus recorded before and after phenylephrine stimulation. SDX's impact on arterial contraction was assessed through cumulative dose-response curves. NO synthase inhibitor (Nω-nitro-L-arginine methyl ester) was used to assess SDX's vasodilatory effect over the NO pathway. Results: SDX application resulted in concentration-dependent vasorelaxation in both endothelium-intact and endothelium-denuded groups at certain doses. However, the inhibitory effect of SDX was more pronounced in endothelium-intact rings at higher doses compared to endothelium-denuded rings (p < 0.05). Similar inhibition of contraction curves was achieved for both endothelium-intact and endothelium-denuded rings after L-NAME pre-incubation, suggesting a necessity for NO-related endothelial pathways. Conclusions: SDX exerts a concentration-dependent inhibition on arterial contraction, emphasizing the critical role of an intact endothelium and NO-mediated pathways in this process. This underscores SDX's potential in treating endothelial dysfunction-related pathologies.

Current challenges in the prevention and management of post-thrombotic syndrome-towards improved prevention

Post-thrombotic syndrome (PTS) is a common and potentially debilitating complication of deep vein thrombosis (DVT), affecting up to 50% of DVT patients. The consequence of this chronic condition includes reduced quality of life, increased use of the healthcare system and decreased productivity. The societal impact of this condition is projected to increase, given our ageing population and increased burden of thrombotic diseases. Despite significant recent advances in our understanding of PTS, many unanswered questions remain. Currently, there are few effective and proven options for established PTS; hence, the emphasis should be on instituting effective prevention to reduce the progression to PTS. Effective anticoagulation lowers the risk of PTS, with direct oral anticoagulants appearing to outperform vitamin-K antagonists. However, the evidence for elastic compression stockings and endovascular thrombolysis or thrombectomy techniques remains unclear. Accurate identification of individuals at high risk of developing PTS may also improve the targeting of preventative interventions. This review will examine the current body of evidence regarding PTS, with a focus on preventative strategies as well as novel biomarkers.

Sulodexide Develops Contraction in Human Saphenous Vein via Endothelium-Dependent Nitric Oxide Pathway

Chronic venous disease (CVD) is a proqgressive and underestimated condition related to a vicious circle established by venous reflux and endothelial inflammation, leading to vein dilation and histology distortion, including loss of media tone. Sulodexide (SDX) is a drug restoring the glycocalyx that demonstrated endothelial protection and permeability regulation, together with anti-thrombotic and anti-inflammatory roles. In the lab it also exhibited vein contractility function. The aim of the present study was to show the possible role of endothelium and nitric oxide pathway on SDX's veno-contractile effect on human saphenous veins. The remnants of great saphenous vein (GSV) segments (n = 14) were harvested during coronary artery bypass graft surgery. They were dissected as endothelium-intact (n = 8) and denuded rings (n = 6). First, a viability test was carried out in bath with Krebs-Henseleit solution to investigate a control and basal tension value. After this, cumulative doses of SDX were applied to rings and contraction values were studied in endothelium-intact phenylephrine (PheE, 6 × 10^-7 M) pre-contracted vein rings. Finally, endothelium-intact PheE pre-contacted vein rings were treated by nitric oxide synthase inhibitor Nω-nitro-L-arginine methyl ester (L-NAME, 10^-4 M) for 10 min. Contraction protocol was applied, and contraction values were measured in cumulative doses of SDX. The same protocol was applied to endothelium-denuded vein rings to investigate the effect of SDX. Saphenous vein rings showed an increase in contraction to cumulative doses of SDX. In endothel-intact rings, KCL-induced contraction from 92.6% ± 0.3 to 112.9% ± 0.4 with cumulative SDX doses. However, SDX did not show any veno-contractile effect on endothel-denuded rings. In denuded rings contraction responses measured from 94.9% ± 0.3 to 85.2% ± 0.3 with increasing doses of SDX, indicating no significant change. Nitric oxide synthase inhibitor (L-NAME) prohibited the contraction response of the sulodexide in all dosages, indicating that the contractile function of SDX was mediated by endothelial derived nitric oxide. Results of endothel-intact and denuded rings with L-NAME showed a similar incline with denuded rings with SDX only. The results confirmed SDX's veno-contractile effect in human samples, by means of nitric oxide synthase pathways involvement.

Can we predict and prevent the postthrombotic syndrome?

Postthrombotic syndrome (PTS) remains one of the major late complications of deep vein thrombosis (DVT) with a reported prevalence from 10 to 50%. Many factors were found to be related with the development and severity of PTS such as ipsilateral recurrent DVT, advanced age, obesity, ilio-femoral DVT and primary chronic venous disease presence. Some PTS prediction models have been proposed based on risk factor weight. However, it is still difficult to predict which patient with DVT will develop PTS and thus, the clinical application of these models remains limited. Among the identified problems the heterogeneity of the DVT patient population together with the variety of PTS clinical presentations and difficulties concerning PTS severity assessment should be mentioned. Difficulties on the implementation of the specific and objective PTS identification method have also the significant influence on the research focusing on PTS prevention modalities including risk factor modification, compression treatment, anticoagulation and invasive DVT treatment. In this review, the current approach and knowledge on PTS prediction and prevention are presented, including the conservative and invasive DVT treatment possibilities.

Post-thrombotic Syndrome: Preventative and Risk Reduction Strategies Following Deep Vein Thrombosis

Venous disease is common in the general population, with chronic venous disorders affecting 50–85% of the western population and consuming 2–3% of healthcare funding. It, therefore, represents a significant socioeconomic, physical and psychological burden. Acute deep vein thrombosis, although a well-recognised cause of death through pulmonary embolism, can more commonly lead to post-thrombotic syndrome (PTS). This article summarises the pathophysiology and risk factor profile of PTS, and highlights various strategies that may reduce the risk of PTS, and the endovenous management of iliofemoral deep vein thrombosis. The authors summarise the advances in PTS risk reduction strategies and present the latest evidence for discussion.

[Glycocalyx as a determining factor in development of endothelial venous dysfunction and possibilities of correction thereof]

Modern vascular surgery has the data on a substantial role of the endothelium in pathogenesis of vascular diseases. Endothelial dysfunction is associated with a wide range of pathological processes including those in chronic diseases of lower-limb veins. The discovery of the endothelial glycocalyx made it possible to evaluate its role in the development of endothelial dysfunction as a trigger mechanism in impairment of venous blood flow. The understanding of the unifying role of endothelial dysfunction in pathology in various fields of medicine provides a possibility of predicting the development of serious socially significant diseases such as cardiovascular diseases, diabetes mellitus, obstetrical complications, and to correct the conditions associated therewith. The present study was aimed at carrying out a systematic literature review, thus making it possible to evaluate the role of the endothelial glycocalyx in the development of endothelial dysfunction, as well as to determine therapy with sulodexide capable of decreasing the probability of the onset of endothelial dysfunction at the expense of an anti-inflammatory, antithrombotic, and angioprotective effect on the endothelial wall.

Sulodexide for the Symptoms and Signs of Chronic Venous Disease: A Systematic Review and Meta-analysis

INTRODUCTION

Chronic venous disease (CVD) is a common condition associated with valvular dysfunction, venous hypertension and endothelial inflammation. Sulodexide facilitates the healing of venous ulcers and is frequently used in patients with CVD without ulcer. This review assessed the efficacy and safety of sulodexide for treatment of signs and symptoms of lower extremity CVD.

METHODS

We searched MEDLINE, EMBASE, CINAHL and AMED as well as the Cochrane Central Register of Controlled Trials and the World Health Organisation (WHO) International Clinical Trials Registry Platform Search Portal. We also manually searched potentially relevant journals, conference proceedings and journal supplements. Any study monitoring any effect of sulodexide in patients with CVD at any stage of the disease, classified or non-classified, was considered. Treatment effects were estimated using standardised mean differences (SMDs), mean differences (MDs) and risk ratios (RRs), as appropriate. We calculated 95% confidence intervals (CIs) and heterogeneity (Q, tau and I²).

RESULTS

The search found 64 studies, but only 23 provided data on 7153 participants (mean age 55 years; 68% female). The 13 studies providing extractable quantitative information included 1901 participants (mean age 55.2 years; 65% female). Sulodexide decreased the intensity of pain, cramps, heaviness, oedema and total symptom score and reduced inflammatory mediators in patients with CVD. The risk of adverse events (AEs) was not different between sulodexide and placebo or heparan sulphate (RR 1.31, 95% CI 0.74-2.32; I² = 0%; 270 participants). The overall risk of AEs with sulodexide was low: 3% (95% CI 1-4%) estimated from 3656 participants.

CONCLUSION

Sulodexide was found to have a beneficial venoactive effect on the major signs and symptoms of CVD such as pain, cramps, heaviness and oedema without increasing the risk of AEs. It is also likely to exert a systemic effect on the course of CVD by interfering with inflammatory chemokines.

Recurrent retinal vein thrombosis: prevention with Aspirin, Pycnogenol®, ticlopidine, or sulodexide

BACKGROUND

The aim of this study is to evaluate the use of Aspirin, Pycnogenol®, ticlopidine, and sulodexide to reduce the incidence of new RTV (retinal vein thrombosis) after a first episode. Pycnogenol® is an anti-inflammatory, anti-edema, mild antiplatelet-antithrombotic agent.

METHODS

The registry study evaluated the number of repeated episodes of RVT in 12 months. Possible managements were: standard management (SM); SM + Aspirin (100 mg/once day; if there were no tolerability problems); SM + Pycnogenol (100 mg/day); SM and ticlopidine (200 mg/day); SM + sulodexide (500 ULS/day). The number of subjects age and sex, distribution, the percent of smokers, the vision were comparable at inclusion.

RESULTS

307 subjects completed the study, 44 in the SM group, 90 in the Pycnogenol® group, 90 in the aspirin group, 45 in the ticlopidine group and 38 in the sulodexide group. At 12 months, recurrent RVT was documented in 22.7% of controls (SM), 3.3% of Pycnogenol® subjects (P<0.05 vs. SM; 19.4% difference). There were RVTs in 15.5% subjects using Aspirin (-7.2% vs. SM). Ticlopidine also reduced (P<0.05) the incidence of RVT in comparison with SM (-9.1%). Sulodexide reduced the occurrence of new RVT (-9.5% vs. SM). Edema was better controlled with the supplement than with all other treatments (P<0.05) (edema present in only 5.5% of the Pycnogenol® subjects). Pycnogenol® had a very good tolerability and safety profile (no patient had to stop treatment).

CONCLUSIONS

Pycnogenol® is the only product able to control edema and this may reduce the incidence of recurrent RVT. This retrospective registry indicates that Aspirin, Pycnogenol®, ticlopidine an sulodexide reduce recurrent RVT without side effects. Larger studies should be planned to involve a wider range of conditions, diseases and risk factors associated with RVT and to its recurrence.

Sulodexide promotes arterial relaxation via endothelium-dependent nitric oxide-mediated pathway

Sulodexide (SDX) is a highly purified glycosaminoglycan with antithrombotic and profibrinolytic properties and reported benefits in thrombotic and atherosclerotic vascular disorders. However, the effects of SDX on vascular function are unclear. We tested whether SDX affects vascular relaxation and examined the potential underlying mechanisms. Isolated segments of male rat abdominal aorta and mesenteric artery were suspended in a tissue bath, and the changes in arterial contraction/relaxation were measured. The α-adrenergic receptor agonist phenylephrine (Phe) (10^-9-10^-5 M) caused concentration-dependent aortic and mesenteric artery contraction that was reduced in tissues pretreated with SDX (1 mg/ml). In aortic and mesenteric arterial segments precontracted with submaximal concentration of Phe (3 × 10^-7-6 × 10^-7 M), SDX (0.001-1 mg/ml) caused concentration-dependent relaxation. To test the role of endothelium, SDX-induced relaxation was compared with that of acetylcholine (ACh), a known activator of endothelium-dependent relaxation. In Phe precontracted aorta, ACh relaxation was abolished and SDX relaxation was significantly inhibited by endothelium removal or the nitric oxide synthase (NOS) inhibitor N_ω-nitro-l-arginine methyl ester (L-NAME), suggesting a role of NO. In mesenteric artery, ACh relaxation was abolished by endothelium removal, partially blocked by L-NAME, and completely blocked by a mixture of indomethacin, a cyclooxygenase inhibitor and blocker of the PGI₂-cAMP pathway, and tetraethylammonium, a blocker of K⁺ channels and EDHF-dependent hyperpolarization pathway. In comparison, SDX relaxation of mesenteric artery was almost completely inhibited by endothelium removal or NOS inhibitor L-NAME. SDX enhanced vascular relaxation and increased nitrate/nitrite production in response to all ACh concentrations in the aorta, but only to low ACh concentrations (<10^-7 M) in mesenteric artery. SDX did not affect aortic or mesenteric artery endothelium-independent relaxation to the NO donor sodium nitroprusside. Thus, SDX promotes arterial relaxation via a mechanism involving endothelium-dependent NO production; an effect that could enhance vasodilation and decrease vasoconstriction in vascular disorders.

Sulodexide in venous disease

Sulodexide is a glycosaminoglycan extracted from porcine intestinal mucosa. The purpose of this review is to discuss sulodexide's complex pharmacological profile and its clinical applications for venous disease. Sulodexide has wide-ranging biological effects on the vascular system, including antithrombotic, profibrinolytic, anti-inflammatory, endothelial protective and vasoregulatory effects. Sulodexide has emerged as a potential therapeutic option for the management of chronic venous insufficiency, including venous ulceration, and the prevention of recurrent venous thromboembolism, with a low rate of major bleeding complications. Sulodexide's pleiotropic vascular effects may facilitate the management of common venous disorders.

Sulodexide for Secondary Prevention of Recurrent Venous Thromboembolism: A Systematic Review and Meta-Analysis

Background: Patients with venous thromboembolism have high risk of recurrence after discontinuation of anticoagulant treatment. Extended anticoagulation, such as traditional anticoagulants, can reduce the risk of recurrence but is associated with increased risk of hemorrhage. Sulodexide is a natural glycosaminoglycan mixture which can prevent recurrent venous thromboembolism. However, its clinical efficiency and safety still remain controversial. Methods: A systematic search in Medline, EMBASE, Cochrane Library, Web of Science and bibliographies of retrieved articles was performed. Prospective controlled studies reporting the efficacy and safety of sulodexide on the secondary prevention of recurrent venous thromboembolism were included. Two reviewers independently extracted the following data: first author, year of publication, study design, characteristics of patients, data of interventions, doses of sulodexide, overall duration of drug administration, time of follow-up, efficacy and safety outcomes, adverse effects, and the quality of the included studies. The primary efficacy outcomes were recurrent deep vein thrombosis (DVT) or pulmonary embolism. The secondary efficacy outcomes included distal or superficial vein thrombosis and nonfatal or fatal myocardial infarction, stroke, and acute ischemia of the lower limbs. Safety outcome was possible hemorrhagic episodes. Results: Four studies involving 1,461 patients were enrolled in this study. Meta-analysis showed that sulodexide significantly reduced the recurrent venous thromboembolism [RR 0.51, 95 % CI [0.35, 0.74], P = 0.0004] and superficial vein thrombosis in the sulodexide group [RR 0.41, 95% CI [0.22, 0.76], P = 0.005]. The safety of sulodexide was also reliable. The rate of bleeding was 0.28% in the sulodexide group and 1.60% in the control group, and design of study did not influence these results. Conclusions: Sulodexide could significantly reduce the recurrence of VTE after discontinuation of anticoagulation treatment as compared with placebo.

Prevention and treatment of the post-thrombotic syndrome

Post thrombotic syndrome (PTS) is a common chronic complication of deep vein thrombosis of the leg (DVT). Treatment options are limited therefore emphasis is placed on its prevention. Several risk factors have been recognized, but were so far not used for risk stratification or translation into prediction models. Early interventions did not yet result in more successful preventive treatment strategies; for the acute phase of DVT there is equipoise on the value of elastic compression, as well as on catheter directed thrombolysis. There are no drugs specifically targeted at PTS prevention. The use of anticoagulant medication such as direct oral anticoagulants (DOACs) might decrease PTS incidence, but this needs to be corroborated. Both research into more effective treatment options as well as future PTS management may benefit from a uniform diagnostic strategy and the use of prediction rules to better allocate treatment and thereby increase treatment efficacy.

Sulodexide in Patients with Chronic Venous Disease of the Lower Limbs: Clinical Efficacy and Impact on Quality of Life

Introduction

Chronic venous disease (CVD) of the lower limbs is a common problem. It is more prevalent in women than in men and has a significant impact on patients’ quality of life (QoL) and on the healthcare system. The aim of this study was to evaluate the efficacy of sulodexide in adult patients with CVD of the lower limbs and its effect on patients’ QoL.

Methods

Patients with CVD were treated with sulodexide [250 LSU (lipasemic units) twice daily] for 3 months in a setting of real-life clinical practice. The endpoints of this observational non-comparative, open-label prospective study were the clinical efficacy of sulodexide (evaluated by scoring objective and subjective symptoms with a Likert-type scale) and the impact of sulodexide therapy on patients’ QoL [assessed using the chronic venous insufficiency quality of life questionnaire (CIVIQ)].

Results

The study included 450 patients (mean age 46.9 ± 10.5 years, range 17–78 years). A greater percentage of patients were female (65.4%). Three months of treatment with sulodexide significantly improved all objective and subjective symptoms (p < 0.0001). Overall, patients reported a significant improvement in all QoL scores (p < 0.0001). Adverse events were spontaneously reported by two patients (one case of epigastric pain and one of gastric pain with vomiting).

Conclusion

Oral sulodexide significantly improves both objective and subjective symptoms, as well as functional and psychological aspects of QoL in patients with CVD.

Funding

No funding or sponsorship was received for this study. Sponsorship for article processing charges and open access fees was provided by Alfa Wassermann.

Compression to prevent PTS: a controversy?

Compression therapy, prescribed as elastic compression stockings, is the cornerstone in the management of post-thrombotic syndrome. The effectiveness of elastic compression stockings has recently been called into question in a large randomized placebo-controlled trial. The findings however may be less contradictory than assumed and presented. The mechanistic substrate for the effectiveness of compression therapy is based on its ability to counteract venous hypertension, which is a central aspect in the pathophysiology of post-thrombotic syndrome. Nevertheless, despite elastic compression stockings a significant percentage (20–50%) of patients develops post-thrombotic syndrome, suggesting that there are other factors to be considered next to compression. Every patient has an individual baseline risk value, constituted of non-modifiable and modifiable risk factors (i.e. age, sex, bodyweight etcetera). Straining patients at risk is therefore crucial. Exploring additional or alternative forms of therapy is desirable as well since these are in addition to the risk factors, costs aspects and quality of life, puzzle pieces in the management of post-thrombotic syndrome, which once pieced together enables multifactorial yet individualized therapy.

The post thrombotic syndrome: Ignore it and it will come back to bite you

Post thrombotic syndrome (PTS) is a very common chronic complication of deep venous thrombosis (DVT), as three out of ten patients with lower extremity DVT will develop PTS. The possibility to identify patients at risk is limited. Diagnosis is challenging, because there is no gold standard diagnostic method. Progress in diagnostic options may therefore change future diagnostic strategies. The better understanding of pathophysiologic processes that underlie PTS may stimulate the development of treatment modalities and improve and diversify management options. The quest for adequate preventive strategies and treatment is important because PTS has a detrimental effect on patients' quality of life and is associated with increased healthcare as well as societal costs. The problem of PTS prevention is therefore clearly relevant to patients, doctors as well as policy makers.