Study Of The Effect Of Polysaccharides On Hemostasis

The effect of sulfated polysaccharides on the hemostatic system in conditions in vitro. Platelet-rich plasma was obtained by centrifugation at 200 g for 10 minutes. The remaining citrate blood was further centrifuged at 1500 g for 10 min to obtain platelet-poor plasma. The antithrombin activity of the compounds was evaluated in vitro by their effect on the recalcification time, thrombin, and prothrombin time of human blood plasma stabilized with a 3.8% sodium citrate solution in the ratio of 9:1. In studies conducted on the blood plasma of rats, it was found that the studied compounds, to varying degrees, lengthen the APTT, APTT, prothrombin time. At the same time, anticoagulant activity was established to block one of the factors II, V, X. Polysaccharide exhibit a combined anticoagulant effect in the body, due to which they are classified as anticoagulant and antithrombin agents.

Download Full-text

The effect of Sulphated cellulose on System of Haemostasis

Research Journal of Pharmacy and Technology ◽

10.52711/0974-360x.2021.00571 ◽

2021 ◽

pp. 3283-3289

Author(s):

Nozim N. Khoshimov ◽

Guli M. Raimova ◽

Kabul E. Nasirov ◽

Zulayho A. Mamatova ◽

Nodira I. Mamadaliyeva ◽

...

Keyword(s):

Blood Plasma ◽

Platelet Rich Plasma ◽

Anticoagulant Activity ◽

Experimental Studies ◽

Mechanisms Of Action ◽

Human Blood Plasma ◽

Thrombin Time ◽

Sulphated Polysaccharides ◽

Antithrombin Activity

Experimental studies and analyses of new compounds with different mechanisms of action on systemic haemostasis are relevant for the identification and development of potential pharmacological preparations. The modified sulphated polysaccharides with anticoagulant and antithrombin activity were studied for haemostasis. Platelet-rich plasma was obtained by centrifugation at 200g for 10 minutes. The remaining citrate blood was further centrifuged at 1500g for 10 min to obtain platelet-poor plasma. The antithrombin activity of the compounds was evaluated In vitro by their effect on the recalcification time, thrombin and prothrombin time of rabbit and human blood plasma stabilized with a 3.8% sodium citrate solution in the ratio 9:1. The results showed that the anticoagulant activity of the studied sulphates increased with an increasing degree of sulphation. Sulphated polysaccharides showed strong anticoagulant activity In vitro. The experimental results showed a significant increase in the coagulation time of blood plasma in tests for prothrombin and thrombin time. These properties of these components are of particular interest, and further detailed studies of the physicochemical characteristics and mechanisms of action of these molecules should be performed, which will eventually allow them to be used as heparin-like drugs.

Download Full-text

The Effect of Warfarin Sodium on the Duration of Platelet Aggregation

Thrombosis and Haemostasis ◽

10.1055/s-0038-1655087 ◽

1967 ◽

Vol 18 (03/04) ◽

pp. 766-778 ◽

Cited By ~ 2

Author(s):

H. J Knieriem ◽

A. B Chandler

Keyword(s):

Platelet Count ◽

Placebo Group ◽

Platelet Aggregation ◽

Prothrombin Time ◽

Platelet Rich Plasma ◽

Healthy Adults ◽

Double Blind Study ◽

Double Blind ◽

Warfarin Sodium

SummaryThe effect of the administration of warfarin sodium (Coumadin®) on the duration of platelet aggregation in vitro was studied. Coumadin was given for 4 consecutive days to 10 healthy adults who were followed over a period of 9 days. The duration of adenosine diphosphate-induced platelet aggregation in platelet-rich plasma, the prothrombin time, and the platelet count of platelet-rich plasma were measured. Four other healthy adults received placebos and participated in a double-blind study with those receiving Coumadin.Although administration of Coumadin caused a prolongation of the prothrombin time to 2 or 21/2 times the normal value, a decrease in the duration of platelet aggregation was not observed. In most individuals who received Coumadin an increase in the duration of platelet aggregation occurred. The effect of Coumadin on platelet aggregation was not consistently related to the prothrombin time or to the platelet count. In the placebo group there was a distinct relation between the duration of platelet aggregation and the platelet count in platelet-rich plasma.The mean increase in the duration of platelet aggregation when compared to the control value before medication with Coumadin was 37.7%. In the placebo group there was a mean increase of 8.4%. The difference between the two groups is significant (p <0.001). Increased duration of platelet aggregation also occurred in two individuals who received Coumadin over a period of 10 and 16 days respectively.

Download Full-text

INFLUENCE OF THE SULFATION PATTERN ON CERTAIN BIOLOGICAL PROPERTIES OF GALACTOSAMINOGLYCANS

10.1055/s-0038-1643251 ◽

1987 ◽

Author(s):

B Casu ◽

L Marchese ◽

A Naggi ◽

G Torri ◽

J Fareed ◽

...

Keyword(s):

Molecular Weight ◽

Dermatan Sulfate ◽

Anticoagulant Activity ◽

Chlorosulfonic Acid ◽

Biological Properties ◽

Sulfated Polysaccharides ◽

Low Molecular Weight ◽

Antithrombotic Activity

In order to investigate the influence of charge distribution and chain length on the biological properties of sulfated polysaccharides, additional sulfate groups were introduced into the galactosaminoglycans, chondriotin sulfate and dermatan sulfate. Using a flexible method (with sulfuric acid and chlorosulfonic acid) for concurrent sulfation and controlled depolymerization, numerous products were obtained and characterized by chemical, enzymatic and nuclear magnetic resonance spectroscopic methods. The biologic actions of these products were profiled in both in vitro and in vivo assays for antithrombotic activity. Despite a weaker in vitro anticoagulant activity, low molecular weight over sulfated galactosaminoglycans produced significant dose-dependent antithrombotic actions in animal models which were similar to the actions observed with oversulfated low molecular weight heparins. These results suggest that a significant antithrombotic activity can be elicited through non-specific interactions of polysulfates with cellular and plasma components, and that clusters of sulfate groups such as the 4-6 disulfate group on D-galactosaminoglycan residues may be important for these interactions. Furthermore, these results, also suggest that supersulfation of glycosaminogly-cans results in products with biologic activity distinct from the native material.

Download Full-text

A Study for the Access to a Semi-synthetic Regioisomer of Natural Fucosylated Chondroitin Sulfate with Fucosyl Branches on N-acetyl-Galactosamine Units

Marine Drugs ◽

10.3390/md17120655 ◽

2019 ◽

Vol 17 (12) ◽

pp. 655 ◽

Cited By ~ 1

Author(s):

Giulia Vessella ◽

Serena Traboni ◽

Anna V. A. Pirozzi ◽

Antonio Laezza ◽

Alfonso Iadonisi ◽

...

Keyword(s):

Chondroitin Sulfate ◽

Anticoagulant Activity ◽

The Body ◽

New Drugs ◽

Coagulation Cascade ◽

Drug Candidate ◽

Heterogeneous Structure ◽

Anticoagulant Drug ◽

Chemical Strategy

Fucosylated chondroitin sulfate (fCS) is a glycosaminoglycan found up to now exclusively in the body wall of sea cucumbers. It shows several interesting activities, with the anticoagulant and antithrombotic as the most attractive ones. Its different mechanism of action on the blood coagulation cascade with respect to heparin and the retention of its activity by oral administration make fCS a very promising anticoagulant drug candidate for heparin replacement. Nonetheless, its typically heterogeneous structure, the detection of some adverse effects and the preference for new drugs not sourced from animal tissues, explain how mandatory is to open an access to safer and less heterogeneous non-natural fCS species. Here we contribute to this aim by investigating a suitable chemical strategy to obtain a regioisomer of the natural fCS polysaccharide, with sulfated l-fucosyl branches placed at position O-6 of N-acetyl-d-galactosamine (GalNAc) units instead of O-3 of d-glucuronic acid (GlcA) ones, as in natural fCSs. This strategy is based on the structural modification of a microbial sourced chondroitin polysaccharide by regioselective insertion of fucosyl branches and sulfate groups on its polymeric structure. A preliminary in vitro evaluation of the anticoagulant activity of three of such semi-synthetic fCS analogues is also reported.

Download Full-text

Inhibition of rat glomerular visceral epithelial cell growth by heparin

AJP Renal Physiology ◽

10.1152/ajprenal.1988.255.4.f781 ◽

1988 ◽

Vol 255 (4) ◽

pp. F781-F786 ◽

Cited By ~ 1

Author(s):

S. Adler

Keyword(s):

Growth Inhibition ◽

Dextran Sulfate ◽

Anticoagulant Activity ◽

Sulfated Polysaccharides ◽

Heparin Binding ◽

Pentosan Polysulfate ◽

The Media ◽

Heparan Sulfates ◽

Visceral Epithelial Cell

The effect of several glycosaminoglycans and sulfated polysaccharides on the growth of cultured rat glomerular visceral epithelial cells (GEC) was studied in vitro. Heparin, one preparation of heparan sulfate proteoglycan, dextran sulfate, and pentosan polysulfate significantly inhibited the growth of several GEC clones studied (36.0-77.1% inhibition at 100 micrograms/ml). Other glycosaminoglycans studied did not affect GEC growth. Growth inhibition by heparin was dose related and did not appear to reflect cytotoxicity. Heparins with high or low affinity for antithrombin inhibited growth to similar degrees. When heparin was fractionated into high- and low-anticoagulant activity fractions by physicochemical means the high activity fraction displayed significantly greater growth inhibition. The degree of growth inhibition significantly correlated with serum concentration in the media (r = 0.64; P less than 0.001). Removal of heparin binding factors from serum resulted in a loss of this correlation as well as less overall growth inhibition. These experiments suggest that interactions of GEC with heparan sulfates and other heparin-like molecules in the extracellular matrix may be important in the control of GEC growth.

Download Full-text

Micro-Clotting of Platelet-Rich Plasma Upon Loading in Hydrogel Microspheres Leads to Prolonged Protein Release and Slower Microsphere Degradation

Polymers ◽

10.3390/polym12081712 ◽

2020 ◽

Vol 12 (8) ◽

pp. 1712

Author(s):

Miran Hannah Choi ◽

Alexandra Blanco ◽

Samuel Stealey ◽

Xin Duan ◽

Natasha Case ◽

...

Keyword(s):

Platelet Aggregation ◽

Intervertebral Disc Degeneration ◽

Therapeutic Potential ◽

Platelet Rich Plasma ◽

Autologous Blood ◽

The Body ◽

Protein Release ◽

Tissue Degeneration

Platelet-rich plasma (PRP) is an autologous blood product that contains a variety of growth factors (GFs) that are released upon platelet activation. Despite some therapeutic potential of PRP in vitro, in vivo data are not convincing. Bolus injection of PRP is cleared rapidly from the body diminishing its therapeutic efficacy. This highlights a need for a delivery vehicle for a sustained release of PRP to improve its therapeutic effect. In this study, we used microfluidics to fabricate biodegradable PRP-loaded polyethylene glycol (PEG) microspheres. PRP was incorporated into the microspheres as a lyophilized PRP powder either as is (powder PRP) or first solubilized and pre-clotted to remove clots (liquid PRP). A high PRP loading of 10% w/v was achieved for both PRP preparations. We characterized the properties of the resulting PRP-loaded PEG microspheres including swelling, modulus, degradation, and protein release as a function of PRP loading and preparation. Overall, loading powder PRP into the PEG microspheres significantly affected the properties of microspheres, with the most pronounced effect noted in degradation. We further determined that microsphere degradation in the presence of powder PRP was affected by platelet aggregation and clotting. Platelet aggregation did not prevent but prolonged sustained PRP release from the microspheres. The delivery system developed and characterized herein could be useful for the loading and releasing of PRP to promote tissue regeneration and wound healing or to suppress tissue degeneration in osteoarthritis, and intervertebral disc degeneration.

Download Full-text

THE RELATIONSHIP BETWEEN HEPARIN DOSAGE AND CLOTTING TIME

Blood ◽

10.1182/blood.v3.10.1197.1197 ◽

1948 ◽

Vol 3 (10) ◽

pp. 1197-1212 ◽

Cited By ~ 25

Author(s):

L. B. JAQUES ◽

ANN G. RICKER

Keyword(s):

Anticoagulant Activity ◽

The Body ◽

Time Response ◽

Fixed Dose ◽

Clotting Time ◽

Anticoagulant Action ◽

India Ink ◽

The Relationship ◽

Heparin Dosage

Abstract 1. The relationship between clotting time and heparin dosage has been studied in the dog. 2. On the addition of heparin to blood in vitro, a linear relation is found between heparin dosage and the logarithm of the clotting time obtained. The sensitivity of the blood sample to the action of added heparin is influenced both by the individual (coagulability of the blood before withdrawal) and by the technics of withdrawal and of determination of the clotting time. It is indicated that alterations in the latter may be used to extend the range of measurable hypocoagulability due to heparin. Incubation of heparin with blood for ten minutes increases its anticoagulant effect. 3. When moderate doses of heparin are injected intravenously, five to fifteen minutes are required for the clotting time to reach a maximum. No evidence of a biphasic response was obtained. The maximum clotting time obtained is greater than it is with the same amount of heparin added to the blood in vitro, due to the effect of incubation of heparin with blood on its anticoagulant activity. The in- terval required for the clotting time to return to normal is quite short, and with a given dosage is constant with different animals. Factors influencing the relation between duration of hypocoagulability and dosage are discussed. 4. A test has been devised to determine the sensitivity of the animal to the anticoagulant action of heparin. The clotting time response to certain concentrations of heparin added to the blood in vitro is determined. A fixed dose of heparin is then injected intravenously and the clotting time response is again determined. The response in vitro measures the sensitivity of the clotting system to heparin, while the in vivo response, when interpreted in the light of the in vitro response, measures the ability of the body to remove heparin from the circulation. 5. By means of this test, it has been determined that anesthesia with pentobarbital decreased the coagulability of the blood, urethane had no effect on coagulability, while the effect of ether was variable. The injection of india ink and evisceration caused a hypercoagulability, while removal of the kidneys had little effect. 6. When the sensitivity of the blood to the anticoagulant action of heparin was tested during these procedures, pentobarbital and nephrectomy had no effect, ether caused an increase in sensitivity, urethane a decrease. The injection of india ink and also evisceration markedly decreased the sensitivity of the blood to the anticoagulant action of heparin. 7. Anesthesia with pentobarbital, ether or urethane, the injection of india ink, removal of the kidneys, or removal of the gastrointestinal tract, had no effect on the duration of heparin action in the body.

Download Full-text

An In Vitro Analysis of the Effects of Intravenous Lipid Emulsion on Free and Total Local Anaesthetic Concentrations in Human Blood and Plasma

Critical Care Research and Practice ◽

10.1155/2014/236520 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7

Author(s):

Louise Ann Clark ◽

Jochen Beyer ◽

Andis Graudins

Keyword(s):

Blood Plasma ◽

Human Blood ◽

Local Anaesthetic ◽

Whole Blood ◽

Lipid Emulsion ◽

Equilibrium Dialysis ◽

Human Blood Plasma ◽

Intravenous Lipid Emulsion ◽

Vitro Effect

Background. Intravenous lipid emulsion (ILE) is recommended as a “rescue” treatment for local anaesthetic (LA) toxicity. A purported mechanism of action suggests that lipophilic LAs are sequestered into an intravascular “lipid-sink,” thus reducing free drug concentration. There is limited data available correlating the effects of ILE on LAs.Aims. To compare the in vitro effect of ILE on LA concentrations in human blood/plasma and to correlate this reduction to LA lipophilicity.Method. One of four LAs (bupivacaine-most lipophilic-4 mg/L, ropivacaine-6 mg/L, lignocaine-14 mg/L, and prilocaine-least lipophilic-7 mg/L) was spiked into plasma or whole blood. ILE or control-buffer was added. Plasma was centrifuged to separate ILE and total-LA concentration assayed from the lipid-free fraction. Whole blood underwent equilibrium dialysis and free-LA concentration was measured. Percent reduction in LA concentration from control was compared between the LAs and correlated with lipophilicity.Results. ILE caused a significant reduction in total and free bupivacaine concentration compared with the other LAs. Ropivacaine had the least reduction in concentration, despite a lipophilicity similar to bupivacaine. The reduction in LA concentration correlated to increasing lipophilicity when ropivacaine was excluded from analysis.Conclusion. In this first in vitro model assessing both free- and total-LA concentrations exposed to ILE in human blood/plasma, ILE effect was linearly correlated with increasing lipophilicity for all but ropivacaine.

Download Full-text