MICRONIZATION ENHANCES THE PROTECTIVE EFFECT OF PURIFIED FLAVONOID FRACTION AGAINST POSTISCHAEMIC MICROVASCULAR INJURY IN THE HAMSTER CHEEK POUCH

The influence of supportive therapy with a six-component myophlebotropic preparation on the reduction of symptoms in patients with symptoms of hemorrhoidal disease

<b>Introduction:</b> Hemorrhoidal disease is the most common disease treated in proctology ambulatories. Conservative treatment is the basic form of treatment for this disease. One of the elements of treatment may be preparations with myoand phlebotropic effects.<b>Aim:</b> To assess the effect of a multi-ingredient myophlebotropic dietary supplement used as an adjunct on the rate and effectiveness of symptom relief in patients with stage II and III hemorrhoidal disease.<b>Material and method:</b> Patients with stage II and III hemorrhoidal disease with clinical symptoms such as pain, burning, itching and bleeding were qualified for the study. The patients were divided into two groups. The control group (Group I) of 29 patients receiving standard local treatment plus placebo and the study group (Group II) of 32 patients receiving the same local treatment and a six-component myophlebotropic product. Symptoms were analyzed at the time of inclusion in the study (day 0), after 4 and 10 days of therapy. The severity of hemorrhoidal disease and the feeling of relief were assessed on the day of inclusion (W0) and after 30 days of therapy.<b>Results:</b> There were no statistical differences between the groups in terms of disease advancement, age, gender, and duration of symptoms. Compared to the moment of inclusion in the study (W0), after 4 days (W1), after 10 days (W2) of taking the multi- -component product, there was a statistically significant improvement in the VAS scale: spontaneous pain and pain during defecation. In the qualitative assessment (yes/no), there were statistically significantly fewer cases of burning in the anus and itching. The treatment did not affect the rate of spontaneous bleeding, which was low at the beginning of the study, but significantly reduced the rate of bleeding during defecation. After 30 days of observation, it was found that the improvement in the severity of hemorrhoidal disease symptoms was significantly higher in the group using the tested preparation. Relief after a month of the study (one-question method) was noted in the group of patients receiving the tested product.<b>Conclusions:</b> The tested six-component myophlebotropic product proved to be effective in reducing the severity of symptoms such as spontaneous pain, pain during defecation, burning/burning in the anus and bleeding during defecation. Statistical significance was demonstrated in the symptom's relief and reduction in the severity of hemorrhoidal disease.

[Common sense of diosmin administration in combined treatment of hemorrhoids]

Flavonoids are herbal medicines and widely used for chronic venous diseases and hemorrhoids. Flavonoid diosmin in both micronized and non-micronized form is a part of various drugs. According to literature data, flavonoids are able to reduce venous stasis, suppress local inflammation, improve venous tone and lymphatic outflow. It should be noted that biological models of in vivo trials have certain limitations while available data of different researches are contradictory. However, flavonoids were recommended for hemorrhoids in view of meta-analysis of 14 trials comparing flavonoids (diosmin, micronized purified flavonoid fraction and rutosides) with placebo in 1514 patients with hemorrhoids and Cochrane review of 24 randomized controlled trials (2,334 participants). These drugs should be administered as a part of complex therapy. At the same time, there is no conclusive evidence to prefer only one of these medicines. There are also no data confirming the benefits of daily dosage of 3000 mg per day of micronized fraction of flavonoids compared with 1800 mg of purified diosmin per day for treatment of acute hemorrhoids.

Cerebral venous collaterals: A new fort for fighting ischemic stroke?

Stroke therapy has entered a new era highlighted by the use of endovascular therapy in addition to intravenous thrombolysis. However, the efficacy of current therapeutic regimens might be reduced by their associated adverse events. For example, over-reperfusion and futile recanalization may lead to large infarct, brain swelling, hemorrhagic complication and neurological deterioration. The traditional pathophysiological understanding on ischemic stroke can hardly address these occurrences. Accumulating evidence suggests that a functional cerebral venous drainage, the major blood reservoir and drainage system in brain, may be as critical as arterial infusion for stroke evolution and clinical sequelae. Further exploration of the multi-faceted function of cerebral venous system may add new implications for stroke outcome prediction and future therapeutic decision-making. In this review, we emphasize the anatomical and functional characteristics of the cerebral venous system and illustrate its necessity in facilitating the arterial infusion and maintaining the cerebral perfusion in the pathological stroke content. We then summarize the recent critical clinical studies that underscore the associations between cerebral venous collateral and outcome of ischemic stroke with advanced imaging techniques. A novel three-level venous system classification is proposed to demonstrate the distinct characteristics of venous collaterals in the setting of ischemic stroke. Finally, we discuss the current directions for assessment of cerebral venous collaterals and provide future challenges and opportunities for therapeutic strategies in the light of these new concepts.

Effects of verapamil, nifedipine, and daflon on the viability of reverse-flow island flaps in rats

Reverse-flow flaps are preferable in reconstructive surgery due to their several advantages. However, they may have venous insufficiency and poor blood flow. In this study, effects of various pharmacological agents on the viability of reverse-flow flaps were investigated. Forty Sprague-Dawley rats were used. Superficial epigastric artery- and superficial epigastric vein-based reverse-flow island flaps were preferred. The rats were divided into 4 groups. Group 1 was considered as the control group. Group 2 was given verapamil 0.3 mg/kg per day, group 3 nifedipine 0.5 mg/kg per day, and group 4 Daflon 80 mg/kg per day for 7 days. On day 7, viable flap areas were measured, angiography was performed, serum nitric oxide levels were evaluated, and histopathological examination was done.The mean flap viability rate was 67.59% (±13.12259) in group 1, 77.38% (±4.12506) in group 2, 74.57% (±3.44780) in group 3, and 85.39% (±4.36125) in group 4 (P = 0.001). The mean nitric oxide level was 31.66 μmol/dL (±2.42212) in group 1, 51.00 μmol/dL (±2.96648) in group 2, 34.00 μmol/dL (±2.96648) in group 3, and 47.66 μmol/dL (±2.80476) in group 4 (P = 0.001). On angiography, there were vessel dilations and convolutions in group 2; capillaries became noticeable, and anastomotic vessels extended toward the more distal part of the flaps in group 4. Histological examinations showed severe inflammation in group 3 and minimal inflammation and venous vasodilatation in group 2.Verapamil and Daflon in therapeutic doses significantly increased the viability of reverse-flow island flaps. However, nifedipine did not make a significant contribution to the flap viability. The results of this study will contribute to the literature about the hemodynamics of reverse-flow island flaps and guide further studies on the issue.

Diosmin – Isolation Techniques, Determination in Plant Material and Pharmaceutical Formulations, and Clinical Use

Diosmin is a naturally occurring flavone glycoside used in the treatment of venous diseases. In this review, we present the clinical aspects of the use of diosmin preparations in venous stasis, hemorrheologic disorders and vein wall remodeling. Because of its multiple applications in biology and its many therapeutic activities, research on isolation and identification of diosmin is of high relevance. The aim of this review is to present an overview of techniques of isolation and separation of diosmin in plant material, pharmaceutical formulations such as Daflon®, Diosed® and Dioven® tablets, and biological fluids.

A pro-inflammatory profile of endothelial cell in Lonomia obliqua envenomation

Lonomia obliqua envenomation is characterized by intense local inflammatory reaction, which, dependent on the severity of the case, is followed by severe clinical manifestations related to hemorrhagic disorders that can lead to fatal outcome. These effects were imputed to several toxins present in L. obliqua venom, which are responsible for procoagulant, anticoagulant as well as antithrombotic activities, being also able to interfere with vascular cells functions. In this work, the intravital microscopy analysis show that after administration of low doses of L. obliqua venom (1-3 μg/ml) on hamster cheek pouch, there was no alterations neither on arterioles or venules caliber nor in the vascular permeability up to 30 min. However, after 10 min in contact with venom occurred a clear activation in the vascular bed, characterized by an increase in leukocyte rolling and adhesion on endothelium of hamster cheek pouch venules. A confocal analysis of vascular beds, confirmed these results showing an increase in endothelial E-selectin and VCAM-1 expression. The effects of L. obliqua venom on human endothelial cell (EC) in vitro were also investigated. The treatment of EC with venom (1-3 μg/ml) did not affect cell viability. However, at concentrations as low as 3 μg/ml of L. obliqua venom modifies actin cytoskeleton dynamics, and increases focal adhesion contacts, inducing stress fiber formation, focal adhesion kinase (FAK) phosphorylation and its subsequent association to actin. These effects are followed by the activation of NF-κB pathway, a critical signaling in several events associated to vascular inflammation. Accordingly, L. obliqua venom leads to a significant increase in COX-2, NOS-2, HO-1, MMP-2 and MMP-9 expression. Taken together the data show that, even at low concentrations, L. obliqua venom can activate endothelial cells, which assume a pro-inflammatory profile, contributing for local effects and probably also for systemic disturbances due to its ability to modulate the properties of the vascular system.

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

OBJECTIVES

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

MATERIAL AND METHODS

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

RESULTS

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

CONCLUSIONS

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

The effect of purified micronized flavonoid fraction on the healing of anastomoses in the colon in rats

PURPOSE

Anastomotic leakage of colonic and rectal anastomoses is a major complication after large intestine surgery. Many factors influence the healing of colon anastomoses. Flavonoids have been recognized for centuries as physiologically active constituents that are used to treat human diseases. We studied the effects of a clinically used, micronized, purified flavonoid fraction on the healing of colonic anastomosis in rats.

METHODS

Male Sprague-Dawley rats were used. The flavonoid group of rats received 100 mg/kg per day of Daflon for 14 days until surgery. Thereafter, a resection and anastomosis were performed. The bursting pressure of the anastomoses and the hydroxyproline levels of the perianastomotic tissue were determined to evaluate the healing on the third and seventh days of surgery for both flavonoid and control groups.

RESULTS

The bursting pressure of the flavonoid group was higher on the seventh day. The hydroxyproline levels of the flavonoid group were significantly higher than in the control group on both the third and seventh days after surgery.

CONCLUSIONS

Although the micronized purified flavonoid fraction has some inhibitory properties on the healing of the anastomosis, its net effect was to obtain a better anastomotic healing of the colon in rats.

Alpha-phenyl-N-tert-butyl nitrone (PBN) derivatives: synthesis and protective action against microvascular damages induced by ischemia/reperfusion

Nitrones 4-7, structurally related to PBN (1), were prepared by reaction of the corresponding aromatic aldehydes with N-tert-butyl hydroxylamine. The protective effects of these nitrones against microvascular damages in ischemia/reperfusion in the 'hamster cheek pouch' assay were studied and 1, as well as 4a, 4b, and 7 (derived from piperonal, O-benzyl vanillin, and furfural, respectively), showed to be more active than shark cartilage or alpha-tocopherol. No correlation was found between the protective effect of these nitrones and their logP (partition coefficient) or their capacity to trap (*)OH and (*)CH(3) radicals.