Antiangiogenic activities of bemiparin sodium, enoxaparin sodium, nadroparin calcium and tinzaparin sodium

Preparation of chitosan nanoparticles for simultaneous drug delivery of dacarbazine and enoxaparin in melanoma

The aim of this study was to investigate the anti-melanoma and anti-angiogenic effects of enoxaparin surface-coated dacarbazine-loaded chitosan nanoparticles (Enox-Dac-Chi NPs). The prepared Enox-Dac-Chi NPs had a particle size of 367.95 ± 1.84 nm, zeta potential of -7.12 ± 0.25 mV, efficiency of drug loading (DL%) of 73.90 ± 3.84 %, and attached enoxaparin percentage of 98.53 ± 0.96 %. Both drugs had extended-release profiles and approximately 96 % of enoxaparin and 67 % dacarbazine were released within 8 h. The Enox-Dac-Chi NPs with IC₅₀ of 59.60 ± 1.25 μg/ml were the most cytotoxic against melanoma cancer cells compared with chitosan nanoparticles containing only dacarbazine (Dac-Chi NPs) and free dacarbazine. There was no significant difference between the cellular uptake of Chi NPs and enoxaparin coated Chi NPs (Enox-Chi NPs) in B16F10 cells. Enox-Chi NPs with an average anti-angiogenic score of 1.75 ± 0.125 had more anti-angiogenic effect than enoxaparin. The results showed that simultaneous delivery of dacarbazine and enoxaparin by chitosan nanoparticles can enhance the anti-melanoma effect of dacarbazine. Additionally, enoxaparin can prevent the melanoma metastasis by its anti-angiogenic activity. Thus, the designed nanoparticles can be introduced as effective drug delivery vehicles for the treatment and prevention of metastatic melanoma.

APIXABAN'ın DOZA BAĞLI ANTİANJİYOJENİK POTANSİYELİ: Deneysel bir bakış

Amaç: Direkt oral antikoagülanlar (DOAK'lar), tromboembolizmin tedavisi ve önlenmesi için geleneksel tıbbi rejimlere iyi alternatiflerdir. Apixaban, bu yeni geliştirilen ilaçların daha popüler varyasyonlarından biridir. Antikoagülan potansiyelinin yanı sıra, olası hücresel etkiler gelecekteki çalışmaların konusu olmaya devam etmektedir. Bu çalışmanın amacı, korioallantoik membran (CAM) modelinde apiksaban'ın olası antianjiyogenik etkilerini araştırmaktı. Yöntem: Apixaban'ın 10-4, 10-5 ve 10-6 M konsantrasyonlarında ilaç peletleri hazırlandı ve yumurta inkübasyonunun dördüncü gününde korioallantoik membrana yerleştirildi. Sekizinci günde, membranların tüm vasküler yoğunlukları, bilinen bir monoklonal, insanlaştırılmış, vasküler endotelyal büyüme faktörü inhibitörü olan 10-6 M'lik bir bevacizumab konsantrasyonu ile karşılaştırıldı. Sonuçlar: 10-4 M apiksaban konsantrasyonunun, bevacizumabınkine benzer güçlü bir antianjiyogenik potansiyele sahip olduğunu bulduk. Bununla birlikte, daha düşük bir apiksaban dozunda (10-5 M, 10-6 M) orta düzeyde antianjiyogenik potansiyel vardı. Daha yüksek antianjiyogenik potansiyel dozlarının (10-4 M konsantrasyon) daha düşük dozlarda apiksaban (10-5 M, 10-6 M) ile karşılaştırılması, önemli istatistiksel farklılıklar ortaya çıkardı (p < 0.05). Sonuç: Sonuçlarımız, yüksek doz apiksaban'ın güçlü antianjiyogenik potansiyele sahip olduğunu göstermektedir. Bu etkinin kesin mekanizması bilinmemektedir. Bu pilot sonuçlar, DOAK'lara yeni bir bakış elde etmek için daha ileri çalışmalarla doğrulanmalıdır.

Green and rapid preparation of long-term stable aqueous dispersions of fullerenes and endohedral fullerenes: The pros and cons of an ultrasonic probe

A green, scalable, and sustainable approach to prepare aqueous fullerene dispersions (AFD) C60, C70, endohedral metallofullerene Gd@C82, and their derivatives C60Cl6, C70Cl10, and supramolecular and ester-like derivatives, 10 fullerene species total, is proposed. For the first time, an immersed ultrasonic probe was used to preparing dispersions for pristine fullerenes without addends. Both ultrasound-assisted solvent-exchange and direct sonication techniques for AFD preparation using an immersed probe were tested. The average time for AFD preparation decreases 10-15 times compared to an ultrasound-bath-assisted technique, while final fullerene concentrations in AFDs remained at tens of ppm (up to 80 ppm). The aqueous dispersions showed long-term stability, a negatively charged surface with a zeta potential up to -32 mV with an average nanocluster diameter of no more than 180 nm. The total anionic and cationic compositions of samples were found by inductively coupled plasma atomic emission spectroscopy and chromatographic techniques. The highlights and challenges of using an ultrasound probe for AFD production are discussed.

In Vitro Study of Synergic Effect of Cisplatin and Low Molecular Weight Heparin on Oral Squamous Cell Carcinoma

Objectives

To evaluate the possible synergic effect of cisplatin and low molecular weight heparin (LMWH) on oral squamous cell carcinoma (OSCC).

Materials and Methods

Cisplatin and enoxaparin sodium, alone or in combination, were administered at doses of 1, 2, 4, 8 and 10 µM and 0.1, 0.5, 1, 5, 10, 50, and 100 µg/ml, respectively, to the H357 human OSCC line. The effects on cell viability and apoptosis were evaluated after 24, 48, and 72 h and on cell migration after 18 and 24 h.

Results

10 µM concentration of cisplatin produced the greatest decrease in cell viability, with significant differences at 24 (p=0.009), 48 (p=0.001) and 72 h (p = 0.003); the 100 µg/ml dose of enoxaparin produced the greatest decrease in cell viability but without significant differences (p>0.05). When different concentrations of cisplatin and enoxaparin were combined, it was found that 100 µg/ml enoxaparin sodium produced the greatest synergic effect on cell viability reduction. In analyses of apoptosis and cell migration, it was found that the combination of cisplatin at 8 or 10 μM and 100 μg/ml enoxaparin produced a higher rate of apoptosis at 24, 48, and 72 h and a greater reduction in cell migration at 18 and 24 h.

Conclusions

A combination of cisplatin and enoxaparin sodium shows a synergic effect that reduces cell viability and cell migration capacity and increases the apoptosis of human OSCC cells.

Clinical relevance

Enoxaparin may be beneficial in chemotherapy for patients with OSCC; this finding requires further clinical and laboratory investigation.

Modulation of angiogenesis by topical application of leptin and high and low molecular heparin using the Japanese quail chorioallantoic membrane model

Pathological angiogenesis characterized by uncontrollable vessel growth is an accompanying feature of many diseases. The avian embryo chorioallantoic membrane (CAM) is an excellent model for angiogenesis research. In our study we used a less common Japanese quail CAM model for the testing of angiogenic potential of leptin, high-molecular (heparin sodium) andlow-molecular (nadroparin calcium) heparins. Heparins play a significant role in vascular endothelial cell function, and they are able to modulate the activities of angiogenic growth factors. On embryonic day 7 leptin (5 μg per CAM), heparin sodium (75 IU per CAM) and nadroparin calcium (47.5 IU per CAM) in 500 μl PBS were applied on the CAM surface. After 24 h the fractal dimension (Df) of the vasculature was evaluated. Samples from each group were histologically analyzed and VEGF-A and Quek1 expression were detected by qPCR. Df was significantly increased in the leptin group. A moderate stimulatory effect of heparin sodium and an inhibitory effect of nadroparin calcium were observed. Both leptin and heparin sodium caused a noticeable increase in the CAM thickness compared to the control and nadroparin calcium groups. We observed an increased number of blood vessels and accumulation of fibroblasts. There was no significant impact on gene expression of VEGF-A and Quek1 24 h after treatment, however, trends similar to the changes in Df and CAM thickness were present. The resulting effect of nadroparin administration on Quek1 levels was exactly the opposite to that of leptin (p < 0.05).

Low molecular weight heparin and direct oral anticoagulants influence tumour formation, growth, invasion and vascularisation by separate mechanisms

The bidirectional association between coagulation and cancer has been established. However, anticoagulant therapies have been reported to have beneficial outcomes by influencing the vascularisation of the tumours. In this study the influence of a set of anticoagulants on tumour formation, invasion and vascularisation was examined. WM-266-4 melanoma and AsPC-1 pancreatic cancer cell lines were treated with LMWH (Tinzaparin and Dalteparin), and DOAC (Apixaban and Rivaroxaban) and the rate of tumour formation, growth and invasion were measured in vitro. In addition, the influence of these anticoagulants on vascularisation was examined using the chorioallantoic membrane assay (CAM) model and compared to the outcome of treatment with Bevacizumab. Using this model the influence of pharmacological concentrations of the anticoagulant on the growth, invasion and vascularisation of tumours derived from WM-266-4 and AsPC-1 cells was also measured in vivo. Tinzaparin and Daltepain reduced tumour formation and invasion by the cell lines in vitro, but with dissimilar potencies. In addition, treatment of CAM with LMWH reduced the local vascular density beyond that achievable with Bevacizumab, particularly suppressing the formation of larger-diameter blood vessels. In contrast, treatment with DOAC was largely ineffective. Treatment of CAM-implanted tumours with LMWH also reduced tumour vascularisation, while treatment of tumours with Apixaban reduced tumour growth in vivo. In conclusion, LMWH and DOAC appear to have anti-cancer properties that are exerted through different mechanisms.

Effects of Bemiparin Sodium Versus Dabigatran Etexilate After Anastomosis in Rat Carotid Arteries on the Development of Neointima and Thrombolytic Efficacy

BACKGROUND

Revascularization before infarct development after cerebral ischemia may affect morbidity. The success of revascularization can be less than expected because of spontaneous thrombosis or restenosis with intimal hyperplasia. The aim of this study was to compare dabigatran etexilate, a direct thrombin inhibitor, with bemiparin sodium, a second-generation low-molecular-weight heparin, after carotid artery anastomosis.

METHODS

This study used 24 randomly selected Sprague-Dawley rats. The rats were separated into 3 equal groups: group 1 (control group); group 2 (dabigatran group), in which dabigatran 10 mg/kg was orally administered for 7 days; and group 3 (bemiparin group), in which bemiparin 250 IU/kg was subcutaneously administered for 7 days. The right-side carotid artery of rats was used for anastomosis and the left-side carotid artery was used for the control. The carotid artery was explored and transected. Anastomosis was applied using 10/0 polypropylene sutures. After 7 days of treatment, the right and left carotid arteries were removed. Lumen diameter, lumen area, tunica media thickness, edema, vessel wall injury, intimal hyperplasia, thrombus, and inflammation were evaluated in tissue biopsy specimens.

RESULTS

Bemiparin used after anastomosis caused less thickening of tunica media and reduced intimal hyperplasia but did not decrease lumen diameter and area. Dabigatran increased edema and inflammation but did not prevent intimal hyperplasia.

CONCLUSIONS

Bemiparin reduced intimal hyperplasia and prevented thrombosis angiogenesis, but dabigatran did not prevent intimal hyperplasia, and its anticoagulation effect was more than the antithrombotic effect.

Production and characterization of cellulose acetate - titanium dioxide nanotubes membrane fraxiparinized through polydopamine for clinical applications

The present paper introduces a study on the preparation and characterization of cellulose acetate - TiO₂ nanotubes membrane. In order to be used as a hemodialysis membrane, fraxiparinized nanotubes have been incorporated into the cellulose matrix. Fraxiparine embedding was performed via strong binding ability of dopamine. Composite membrane was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and water contact angle measurement. Electrochemical impedance spectroscopy was used to correlate the morphology of composite membrane with its electrochemical properties. Mott-Schottky test proved titanium dioxide semiconductor incorporation in composite membrane. Permeation test was made to determine pure water flux. The obtained results showed that addition of nanotubes had a positive impact on membrane permeation compared with a control polymeric membrane.

Sets of serum exosomal microRNAs as candidate diagnostic biomarkers for Kawasaki disease

Although Kawasaki disease is the main cause of acquired heart disease in children, no diagnostic biomarkers are available. We aimed to identify candidate biomarkers for diagnosing Kawasaki disease using serum exosomal microRNAs (miRNAs). Using frozen serum samples from a biobank, high-throughput microarray technologies, two-stage real-time quantitative PCR, and a self-referencing strategy for data normalization, we narrowed down the list of biomarker candidates to a set of 4 miRNAs. We further validated the diagnostic capabilities of the identified miRNAs (namely, CT(miR-1246)-CT(miR-4436b-5p) and CT(miR-197-3p)-CT(miR-671-5p)) in 79 samples from two hospitals. We found that this 4-miRNA set could distinguish KD patients from other febrile patients as well as from healthy individuals in a single pass, with a minimal rate of false positives and negatives. We thus propose, for the first time, that serum exosomal miRNAs represent candidate diagnostic biomarkers for Kawasaki disease. Additionally, we describe an effective strategy of screening for biomarkers of complex diseases even when little mechanistic knowledge is available.

Non-anticoagulant effects of low molecular weight heparins in inflammatory disorders: A review

Low molecular weight heparins (LMWHs) are produced by chemical or enzymatic depolymerization of unfractionated heparin (UFH). Besides their well-known anticoagulant effects, LMWHs have also been reported to exhibit numerous anti-inflammatory properties. Previous studies have, however, shown that different production processes result in unique structural characteristics of LMWHs. The structural variations may help explain the different therapeutic spectrums in disease treatment for non-anticoagulant effects. In the present review, we summarize major advances in understanding and exploiting the anti-inflammatory disorder activities of LMWHs, based on mechanistic studies, preclinical experiments and clinical trials. We highlight differences in these activities of commercially available LMWHs produced using different manufacturing processes. We stress the importance of structure-activity relationship (SAR) studies on the non-anticoagulant effects of LMWHs and discuss strategies for exploring new clinical indications.

Role of heparin and non heparin binding serpins in coagulation and angiogenesis: A complex interplay

Pro-coagulant, anti-coagulant and fibrinolytic pathways are responsible for maintaining hemostatic balance under physiological conditions. Any deviation from these pathways would result in hypercoagulability leading to life threatening diseases like myocardial infarction, stroke, portal vein thrombosis, deep vein thrombosis (DVT) and pulmonary embolism (PE). Angiogenesis is the process of sprouting of new blood vessels from pre-existing ones and plays a critical role in vascular repair, diabetic retinopathy, chronic inflammation and cancer progression. Serpins; a superfamily of protease inhibitors, play a key role in regulating both angiogenesis and coagulation. They are characterized by the presence of highly conserved secondary structure comprising of 3 β-sheets and 7-9 α-helices. Inhibitory role of serpins is modulated by binding to cofactors, specially heparin and heparan sulfate proteoglycans (HSPGs) present on cell surfaces and extracellular matrix. Heparin and HSPGs are the mainstay of anti-coagulant therapy and also have therapeutic potential as anti-angiogenic inhibitors. Many of the heparin binding serpins that regulate coagulation cascade are also potent inhibitors of angiogenesis. Understanding the molecular mechanism of the switch between their specific anti-coagulant and anti-angiogenic role during inflammation, stress and regular hemostasis is important. In this review, we have tried to integrate the role of different serpins, their interaction with cofactors and their interplay in regulating coagulation and angiogenesis.

Comparison of Renoprotective Effect of Dabigatran With Low-Molecular-Weight Heparin

OBJECTIVE

The susceptibility of tissue to ischemia-reperfusion (I/R) injury is a major obstacle to tissue regeneration and cellular survival. In this study, we investigated the possible renoprotective effect of dabigatran in an experimental renal I/R model.

METHOD

A total of 25 rats were randomly divided into 5 equal groups. The control group was used to obtain basal values of oxidant and antioxidant biomarkers. The sham group was used to obtain renal prolidase and malondialdehyde (MDA) levels after renal ischemia (for 45 minutes) and reperfusion (for 1 hour). A standard diet was followed. Oral 15 mg/kg dabigatran etexilate was administrated to group I, intraperitoneal 250 U/kg enoxaparin sodium was administrated to group II, and intraperitoneal 250 U/kg bemiparin sodium was administrated to group III for 1 week before the renal I/R was performed. Renal tissue samples were obtained during the first hour of reperfusion to detect renal prolidase and MDA levels in these groups, after which the rats were euthanized.

RESULTS

Renal prolidase levels were significantly higher in the sham group compared with the control group (1834.2 ± 982.3 U/g protein vs 238.8 ± 43.6U/g protein; P = .001). Lower prolidase levels were observed in groups II (838.7 ± 123.8 U/g protein) and III (1012.9 ± 302.3 U/g protein), and the lowest prolidase levels occurred in group I (533.8 ± 96.2 U/g protein; P < .05) when compared with the sham group. The MDA levels were significantly lower (P < .05) in groups I, II, and III (163.9 ± 41.5, 185.4 ± 51.0, and 138.2 ± 22.6 μmol/g protein, respectively) compared with the sham group.

CONCLUSION

Dabigatran etexilate, a univalent direct thrombin inhibitor, may protect the renal tissue more effectively when compared to low-molecular-weight heparins.

Investigation of possible prophylactic, renoprotective, and cardioprotective effects of thromboprophylactic drugs against ischemia-reperfusion injury

The aim of this study was to investigate whether anticoagulant and antiaggregant agents have protective effects against oxidative damage induced by peripheral ischemia-reperfusion (I/R). Groups were created as follows: control group, I/R group (sham group), I/R plus acetylsalicylic acid (Group I), I/R+clopidogrel (Group II), I/R+rivaroxaban (Group III), I/R+bemiparin sodium (Group IV), and I/R+enoxaparin sodium (Group V). In Groups I, II, III, IV, and V, drugs were administered daily for 1 week before I/R creation. Peripheral I/R was induced in the I/R groups by clamping the right femoral artery. The rats were sacrificed 1 hour after reperfusion. Nitrogen oxide levels, malondialdehyde (MDA) levels, paraoxonase-1 (PON1) activity, and prolidase activity were evaluated in both cardiac and renal tissues. There was no significant difference in nitrogen oxide levels between the groups. However, cardiac and renal MDA were significantly higher and PON1 activity was markedly lower in the I/R groups compared with the control group (p<0.05). Although elevated prolidase activity was detected in both the cardiac and renal tissue of the I/R groups, only the sham group and Group V had significantly higher renal prolidase activity (p<0.05). Group V had significantly higher cardiac MDA, PON1, prolidase levels, and renal prolidase activity compared with the sham group (p<0.05). Significant improvement in renal MDA levels was only observed in Group III, and marked improvement was observed in the cardiac MDA levels of Group II when compared with the sham group (p<0.05). Thromboprophylactic agents appear to provide partial or prominent protection against I/R injury.

Effect of detorsion alone and in combination with enoxaparin therapy on ovarian reserve and serum antimüllerian hormone levels in a rat ovarian torsion model

OBJECTIVE

To investigate the effect of enoxaparin on ovarian reserve and serum antimüllerian hormone (AMH) levels in a rat ovarian torsion model.

DESIGN

Experimental study.

SETTING

Experimental surgery laboratory in a training and research hospital.

ANIMAL(S)

Fourteen female Wistar Hannover rats.

INTERVENTION(S)

1) Control group received no special treatment other than abdominal exposure; 2) detorsion-only group received bilateral adnexal torsion (3-hour ischemia), and then after 3-hour torsion period, detorsion (reperfusion) was performed; and 3) detorsion-enoxaparin group received 0.5 mg/kg enoxaparin subcutaneously 2 hours before the same surgery as the detorsion-only group and a second 0.5 mg/kg dose of enoxaparin 24 hours after the first surgeries. Apart from the surgeries, preoperative and postoperative 1-mL blood samples were drawn from the right jugular vein of each rat.

MAIN OUTCOME MEASURE(S)

Preoperative and postoperative serum AMH levels, histopathologic damage scores, and follicle counts in the ovarian tissue of the rats.

RESULT(S)

Vascular congestion and hemorrhage scores were higher in the detorsion-enoxaparin group than in the detorsion-only and control groups. The number of small antral follicles was smaller in the detorsion-only group than in the control group. The difference in the pre- and postoperative AMH levels was higher in the detorsion-only group than in the control and detorsion-enoxaparin groups.

CONCLUSION(S)

The combination of enoxaparin therapy with conventional ovarian detorsion is more effective in protecting the ovarian reserve than detorsion alone.