Effects of glycosaminoglycans on platelet and leucocyte function: role of N-sulfation

Different Treatment Modalities of Oral Lichen Planus-A Narrative Review

Oral lichen planus (OLP) is a chronic inflammatory disease of unknown etiology which affects the oral mucosa. OLP varies in its clinical features from a reticular form that is, in most cases, asymptomatic, to atrophic-erosive, and is accompanied by symptoms of burning sensation and pain followed by difficulty in eating. Given the fact that OLP is a disease of unknown etiology, the treatment is symptomatic and involves suppressing the signs and symptoms of the disease using various topical and systemic drugs. The first line of therapy for treating symptomatic OLP is topical corticosteroids, whereas systemic corticosteroids are used for treating persistent lesions that do not respond to local treatment. However, the lack of convincing evidence on the efficacy of previous therapies, including topical corticosteroids, and numerous side effects that have appeared over recent years has resulted in the emergence and development of new therapeutic options. Some of the therapies mentioned are tacrolimus, efalizumab, dapson, interferon, retinoic acid, photochemotherapy with psoralen and ultraviolet A rays (PUVA), aloe vera, antimalarials, antibiotics and others. These therapies only partially meet the properties of efficacy and safety of use, thus justifying the continuous search and testing of new treatment methods.

Effect of Sulodexide on Circulating Blood Cells in Patients with Mild COVID-19

Background. Despite the fact that COVID-19 usually manifests with severe pneumonia, there is a growing body of evidence that life-threatening multiorgan damage is caused by vascular and hemostatic abnormalities. Since there is no established therapy, assessing antithrombotics is indeed important. Sulodexide, a compound derived from porcine intestinal mucosa is a mixture of fast-moving heparin fraction (80%) and dermatan sulfate (20%), is approved in Europe and currently in trials for COVID-19 indication. Methods. This single-center, prospective, observational study included 28 patients with mild COVID-19 hospitalized in the Central Clinical Hospital of the Presidential Administration of the Russian Federation. Patients in the control group (n = 14) were treated using routine therapy according to current guidelines, while patients in the experimental group (n = 14) had the routine treatment supplemented with daily intravenous injections of sulodexide in 600-unit doses. Scanning electron microscopy was utilized to examine the blood specimens derived from the cubital vein at admission and at 10 days after hospitalization, which was approximately the average duration of patients’ treatment in the hospital (11.6 ± 0.4 days). Results. Sulodexide significantly (by 40%) diminished the score of circulating endothelial cells, potentially indicating its antiviral endothelium-protective properties. It also prevented the extra activation of the platelets and the formation of erythrocytic sludges. Among patients in the control group, the share of activated platelets rose from 37 ± 5% to 45 ± 6% (p = 0.04) over the course of the study period, whereas among patients in the experimental group, the share of activated platelets remained practically unchanged (43 ± 6% vs. 38 ± 4%, p = 0.22). The score of erythrocytic sludges in the control group remained practically the same (4.8 ± 1.1 at admission vs. 3.9 ± 0.9 after 10 days, p = 0.67), whereas in the experimental group, it significantly decreased (from 5.7 ± 1.7 to 2.4 ± 0.9, p = 0.03). Conclusions. Sulodexide is able to defend endothelium, normalize blood, and, seemingly, prevent thrombosis. Therefore, it may be considered as a promising and effective agent for the treatment of patients with mild COVID-19. Broader randomized trials are needed to assess whether the observed findings will transform into sustained long-term clinical benefit.

Reduction of Myocardial Necrosis after Glycosaminoglycan Administration: Effects of a Single Intravenous Administration of Heparin or N-Acetylheparin 2 Hours before Regional Ischemia and Reperfusion

Background

We determined if a single administration of heparin or nonanticoagulant N-acetylheparin could reduce myocardial injury resulting from a 90-minute occlusion of the left circumflex coronary artery (LCX) and 6 hours of reperfusion in the anesthetized canine.

Methods and Results

Heparin (2 mg/kg), N-acetylheparin (2 mg/kg), or vehicle, 0.9% sodium chloride (control), was administered intravenously to separate groups of animals 2 hours before LCX occlusion. To ensure parity of LCX ischemia, only animals with ischemic zone regional blood flow < 0.16 mL/min/g tissue were included in the final analysis. Hemodynamics did not differ among the three study groups. Infarct size as a percentage of the left ventricular area at risk was obtained for each group. Myocardial infarct size was 43.0 ± 3.9% in the vehicle, 28.8 ± 5.8% in the heparin ( P < .05 vs vehicle) and 24.7 ± 4.6% ( P < .05 vs vehicle) in the N-acetylheparin-treated animals.

Conclusion

Pretreatment with heparin or its nonanticoagulant derivative, N-acetylheparin, provides significant protection to the regionally ischemic and reperfused canine myocardium independent of either plasma glycosaminoglycan concentration or alterations in the coagulation system.

Sulodexide: a renewed interest in this glycosaminoglycan

Glycosaminoglycans (GAGs) are the most abundant group of heteropolysaccharides found in the body. These long unbranched molecules contain a repeating disaccharide unit. GAGs are located primarily in the extracellular matrix or on the surface of cells. These molecules serve as lubricants in the joints while at the same time providing structural rigidity to cells. Sulodexide is a highly purified glycosaminoglycan composed of a fast mobility heparin fraction as well as dermatan sulfate. Sulodexide differs from other glycosaminoglycans, like heparin, by having a longer half-life and a reduced effect on systemic clotting and bleeding. In addition, sulodexide demonstrates a lipolytic activity that is increased in comparison to heparin. Oral administration of sulodexide results in the release of tissue plasminogen activator and an increase in fibrinolytic activities. An increasing body of research has demonstrated the safety and efficacy of sulodexide in a wide range of vascular pathologies.

Efficacy of topical pale sulfonated shale oil in the treatment of venous leg ulcers: A randomized, controlled, multicenter study

BACKGROUND

Venous leg ulcers are a growing socioeconomic burden. Pale sulfonated shale oils (PSSO) are used for therapy of inflammatory skin diseases and have been shown to enhance wound healing in vitro and in vivo. The aim of this study was to investigate whether PSSO is capable of enhancing venous ulcer healing beyond compression therapy alone.

METHODS

One hundred nineteen patients were enrolled in this randomized, multicenter, observer-blind study. In the treatment group, PSSO 10% was applied daily for 20 weeks, and the control group received the vehicle only. Wounds were covered by a nonadherent gauze dressing, and compression therapy with short-stretch elastic bandages was performed in an outpatient setting. The primary study end point was defined as cumulative reduction in wound area; the secondary study end point was treatment success as assessed by both physicians and patients. Additionally, adverse events, including changes with respect to physical examination and vital signs, were documented.

RESULTS

At the end of the study period, ulcer size was significantly more reduced in the PSSO group compared with the vehicle group (15 +/- 15.9 to 6.2 +/- 12.9 cm(2) vs 11.4 +/- 14.5 to 10.8 +/- 15.7 cm(2); P = .0005). The cumulative relative reduction in ulcer area was significantly higher in the PSSO group (-4391 +/- 4748.7 vs -231.9 +/- 6283.6 % x days; P < .0001). Relative reduction in wound area was significantly greater in the PSSO group as early as 6 weeks after the beginning of treatment (-47.4 +/- 28.4 vs -23.8 +/- 42.2%; P < .001). PSSO was judged successful both by physicians and patients. There were no significant differences in adverse events (PSSO, 9 [12.2%]; vehicle, 7 [11.1%]. Similarly, tolerability of PSSO was equal to the tolerability of the vehicle.

CONCLUSION

Pale sulfonated shale oils were capable of favoring venous ulcer healing in addition to compression therapy. PSSO should be considered for future wound care protocols for treatment of venous leg ulcers.

Sulodexide attenuates myocardial ischemia/reperfusion injury and the deposition of C-reactive protein in areas of infarction without affecting hemostasis

Several glycosaminoglycans (GAGs) have been demonstrated to protect the ischemic heart against reperfusion injury, in part, by modulating activation of the complement cascade. The present study assessed the cardioprotective effects of sulodexide (KRX-101), a mixture of GAGs composed of 80% low-molecular mass heparin and 20% dermatan sulfate. KRX-101 differs from other GAGs (e.g., heparin) in that it has limited anticoagulant efficacy and can be administered orally. The experimental protocol was designed to determine whether KRX-101 could protect the ischemic myocardium. Anesthetized New Zealand white rabbits underwent 30 min of coronary artery occlusion. Intravenous doses of KRX-101 (0.5 mg/kg, n = 10) or drug diluent (n = 10) were administered at the end of regional ischemia and at each hour of reperfusion. Infarct size, as a percentage of the area at risk, was calculated for both groups. Myocardial infarct size was 31.3 +/- 4.1% in the vehicle- and 17.3 +/- 3.2% in the KRX-101-treated animals (p < 0.05 versus vehicle). Activated partial thromboplastin times determined at baseline (preischemia) and at each hour of reperfusion (n = 4) were not significantly different between vehicle- and KRX-101-treated groups (p = N.S.). Myocardial injury was further assessed by measuring serum levels of cardiac-specific troponin I. KRX-101 administration significantly reduced (p < 0.05) the serum concentration of troponin I during reperfusion. The results suggest that KRX-101 may be an effective adjunctive agent in myocardial revascularization procedures, without the risk of increased bleeding.

Recurrent aphthous stomatitis unresponsive to topical corticosteroids: a study of the comparative therapeutic effects of systemic prednisone and systemic sulodexide

BACKGROUND

Recurrent aphthous stomatitis (RAS) is a common oral condition, the etiology of which remains largely unclear. Numerous therapeutic protocols have been tried. Apart from immunomodulators, no therapy is unequivocally effective, and many systemic therapies have potential adverse effects.

OBJECTIVE

To compare, in patients with frequent RAS unresponsive to conventional therapies, the therapeutic effectiveness of systemic prednisone with that of systemic sulodexide, a low-molecular-weight heparin with immunosuppressive activity but few adverse effects.

METHODS

The study involved a group of 30 patients suffering from frequent minor RAS over >or= 4 months unresponsive to topical corticosteroids. Patients were randomly assigned to one of three study groups: blind therapy with systemic sulodexide or systemic prednisone and control (no treatment). The outcomes were assessed blind on the basis of the days to recovery from pain and days to recovery from ulceration (epithelialization) during the first month of therapy; the number of aphthae appearing during the second month of therapy; and the number of aphthae appearing in the 2 months after the end of the 2-month treatment cycle.

RESULTS AND CONCLUSIONS

The effectiveness of systemic sulodexide was almost comparable with that of systemic prednisone in patients with frequent RAS, without significant adverse effects.

Oral erosive/ulcerative lichen planus: preliminary findings in an open trial of sulodexide compared with cyclosporine (ciclosporin) therapy

OBJECTIVE

To study the effect of the heparinoid sulodexide systemically, compared with topical cyclosporine (ciclosporin), on chronic oral erosive/ulcerative lichen planus.

STUDY DESIGN

An open nonrandomized trial was conducted in two groups of 10 Italian patients with lichen planus, with subjective assessment of pain and assessment of ulceration amelioration by nonblinded clinicians.

RESULTS

Comparable pain relief and amelioration of erosions/ulcers were seen in patients on sulodexide and in those on ciclosporin, but with faster healing in those on sulodexide.

CONCLUSIONS

Sulodexide appears to be as effective, and perhaps more effective, than topical ciclosporin in the therapy of oral lichen planus, and is less expensive, but full double-blind placebo-controlled studies are required.

The nontoxic mushroom Auricularia auricula contains a polysaccharide with anticoagulant activity mediated by antithrombin

An acidic polysaccharide with anticoagulant activity was isolated from the edible mushroom Auricularia auricula using water, alkali or acid extracts. The alkali extract showed the highest anticoagulant activity and was thereby further purified using gel filtration chromatography. Specific anticoagulant activity of the purified polysaccharide was 2 IU/mg and its average mass was approximately 160 kDa. The polysaccharide from this species of mushroom contains mainly mannose, glucose, glucuronic acid and xylose but no sulfate esters. Its anticoagulant activity was due to catalysis of thrombin inhibition by antithrombin but not by heparin cofactor II. Inhibition of Factor Xa by antithrombin was not catalyzed by the polysaccharide. The glucuronic acid residues were essential for the anticoagulant action of the mushroom polysaccharide since the activity disappeared after reduction of its carboxyl groups. In ex vivo tests using rats orally fed with the polysaccharide, we observed an inhibitory effect on platelet aggregation as observed with aspirin, a well-known antiplatelet agent. The polysaccharides from these mushrooms may constitute a new source of compounds with action on coagulation, platelet aggregation and, perhaps, on thrombosis.

Blood compatibility of surfaces with immobilized albumin-heparin conjugate and effect of endothelial cell seeding on platelet adhesion

Endothelial cell (EC) seeding significantly improves the blood compatibility of artificial surfaces. Although a coating consisting of albumin and heparin (alb-hep) is a suitable substrate for seeded ECs, binding of ECs to the substrate further improves when small amounts of fibronectin are present in the alb-hep coating. Alb-hep conjugate was immobilized on carbon dioxide gas plasma-treated polystyrene (PS-CO(2)), thereby significantly increasing the recalcification time of blood plasma exposed to this surface. Furthermore, surface-immobilized alb-hep conjugate inhibited exogenous thrombin. Heparin activity was reduced by adding fibronectin on top of a monolayer of alb-hep conjugate, but not by simultaneous coating of fibronectin and alb-hep conjugate. Coating of PS-CO(2) with alb-hep conjugate significantly decreased contact activation (FXII activation). The number of platelets deposited from blood plasma on PS-CO(2) coated with alb-hep conjugate was twice as high as on PS-CO(2) coated with albumin. Addition of fibronectin to alb-hep conjugate-coated PS-CO(2) had no significant effect on the number of adhered platelets. Seeding of the substrates with ECs significantly reduced the number of adhered platelets under stationary conditions. Platelets deposited onto endothelialized surfaces were primarily found on endothelial cell edges, and sparingly on areas between ECs. In conclusion, alb-hep conjugate-coated surfaces display anticoagulant activity. ECs adhering to and proliferating on this coating significantly decrease the number of platelets which adhere to the surface. Therefore, alb-hep conjugate-coated surfaces form a suitable substrate for seeding of ECs in low density. Although application of fibronectin on top of the coating decreases the anticoagulant activity to some extent, it might be useful in view of the improved adherence of ECs to the coating.

Heparin in inflammation: potential therapeutic applications beyond anticoagulation

In this chapter we have described anti-inflammatory functions of heparin distinct from its traditional anticoagulant activity. We have presented in vivo data showing heparin's beneficial effects in various preclinical models of inflammatory disease as well as discussed some clinical studies showing that the anti-inflammatory activities of heparin may translate into therapeutic uses. In vivo models that use low-anticoagulant heparins indicate that the anticoagulant activity can be distinguished from heparin's anti-inflammatory properties. In certain cases such as hypovolemic shock, the efficacy of a low-anticoagulant heparin derivative (GM1892) exceeds heparin. Data also suggest that nonconventional delivery of heparin, specifically via inhalation, has therapeutic potential in improving drug pharmacokinetics (as determined by measuring blood coagulation parameters) and in reducing the persistent concerns of systemic hemorrhagic complications. Results from larger clinical trials with heparin and LMW heparins are eagerly anticipated and will allow us to assess our predictions on the effectiveness of this drug class to treat a variety of human inflammatory diseases.

Review of pharmacodynamics, pharmacokinetics, and therapeutic properties of sulodexide

Due to various side effects of heparin, such as heparin-induced thrombocytopenia type I or type II, alternative anticoagulants are in clinical development to optimize the anticoagulant regimes in patients requiring low or high anticoagulation dosages. Sulodexide is a highly purified preparation containing a fast-moving heparin fraction as well as dermatansulfate. The pharmacological effects of sulodexide differ substantially from unfractionated heparin and are mainly characterized by a prolonged half-life and reduced effect on global coagulation and bleeding parameters. The lipolytic activity of sulodexide is increased in comparison to unfractionated heparin. Clinical studies demonstrate the safety and efficacy of sulodexide. Specially, oral administration leads to fibrinolytic activities in contrast to oral administration of other glycosaminoglycans. Thus, sulodexide releases tissue plasminogen activator and decreases fibrinogen levels as well as HDL and total cholesterol levels and blood viscosity. Clinical efficacy is demonstrated in peripheral arterial disease, cardiovascular events, in postphlebitic syndrome and on albuminuria in nephropathy.