The in Vitro Anticoagulant Activity of Human Plasma Lipids

1965 ◽  
Vol 13 (02) ◽  
pp. 531-542
Author(s):  
J Cohen ◽  
C. F Reed ◽  
S. B Troup

SummaryThe present report describes the in vitro inhibition of prothrombin consumption by lipid extracted from normal human platelet-poor plasma. Pro-coagulant lipids and the test plasma lipids were dissolved in the same solvent and evaporated to dryness. The dried lipid mixture was emulsified in platelet-poor plasma, and the plasma clotted by recalcification. Inhibition of prothrombin consumption by plasma lipid was observed when the ratio of plasma lipid to procoagulant lipid equaled or exceeded 5:1. The inhibitory effect of plasma lipid on prothrombin consumption was not observed when procoagulant activity was provided by intact platelets or platelet granules.Human plasma lipids have been fractionated on silicic acid columns to permit identification of the plasma lipid component responsible for the inhibition of prothrombin consumption. The inhibitory activity is present in a lipid fraction which is 95% lecithin. Other plasma lipid components exhibit little or no inhibitory activity.

1983 ◽  
Vol 11 (01n04) ◽  
pp. 88-95 ◽  
Author(s):  
Masahiro Yamamoto ◽  
Akira Kumagai ◽  
Yuichi Yamamura

Ascited hepatoma (AH41C or AH130) was transplanted to male rats Donryu, strain. Plasma cholesterol, triglyceride (TG) and non-esterified fatty acid levels were reduced with oral administration of ginseng principle fraction 3 (saponin content, ca. 1/5). Incorporation of 1-[14C]-acetate into total lipids and fatty acids in adipose tissue was increased by fraction 3 administration in both normal and tumor-bearing rats. The incorporation increased in earlier stage of tumor growth and decreased in the later one. Incorporation of 1-[14C]-acetate into total lipid, free and esterified cholesterol, TG and phospholipid in the liver was also enhanced by fraction 3 administration in both normal and tumor-bearing animals. In vitro addition of ginseng principle fraction 4 (saponin content, ca. 1/2) increased incorporation of 1-[14C]-acetate into lipid fraction is adipose tissue and liver. Incorporation of 1-[14C]-acetate into lipid fractions in ascites hepatoma cells remained unchanged with both oral administration of fraction 3 and in vitro addition of fraction 4. DNA and protein synthesis in the tumor cells was not changed with in vitro addition of fraction 4.


Molecules ◽  
2020 ◽  
Vol 25 (19) ◽  
pp. 4371
Author(s):  
Weronika Adach ◽  
Jerzy Żuchowski ◽  
Barbara Moniuszko-Szajwaj ◽  
Malgorzata Szumacher-Strabel ◽  
Anna Stochmal ◽  
...  

Background: The Paulownia Clone in Vitro 112, known as oxytree or oxygen tree, is a hybrid clone of the species Paulownia elongata and Paulownia fortunei (Paulowniaceae). The oxytree is a fast-growing hybrid cultivar that can adapt to wide variations in edaphic and climate conditions. In this work, Paulownia Clone in Vitro 112 leaves were separated into an extract and four fractions (A–D) differing in chemical content in order to investigate their chemical content using LC-MS analysis. The extract and fractions were also evaluated for their anticoagulant and antioxidant properties in a human plasma in vitro. Results: The Paulownia leaf extract contained mainly phenolic compounds (e.g., verbascoside), small amounts of iridoids (e.g., aucubin or 7-hydroxytometoside) and triterpenoids (e.g., maslinic acid) were also detected. Our results indicate that the extract and fractions have different effects on oxidative stress in human plasma treated with H2O2/Fe in vitro, which could be attributed to differences in their chemical content. For example, the extract and all the fractions, at the two highest concentrations of 10 and 50 µg/mL, significantly inhibited the plasma lipid peroxidation induced by H2O2/Fe. Fractions C and D, at all tested concentrations (1–50 µg/mL) were also found to protect plasma proteins against H2O2/Fe-induced carbonylation. The positive effects of fraction C and D were dependent on the dose. Conclusions: The extract and all four fractions, but particularly fractions C and D, which are rich in phenolic compounds, are novel sources of antioxidants, with an inhibitory effect on oxidative stress in human plasma in vitro. Additionally, the antioxidant potential of fraction D may be associated with triterpenoids.


Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 4130-4130 ◽  
Author(s):  
Joseph M. Luettgen ◽  
Tracy A. Bozarth ◽  
Jeffrey M. Bozarth ◽  
Frank A. Barbera ◽  
Patrick Y. Lam ◽  
...  

Abstract Apixaban, previously known as BMS-562247, is a high affinity, highly selective, orally-active, reversible inhibitor of coagulation factor Xa (fXa), in clinical studies as a therapeutic agent for prevention and treatment of thromboembolic diseases. The in vitro characteristics of apixaban were evaluated in purified systems and in human blood from healthy volunteers. Detailed kinetic analysis of apixaban inhibition of human fXa showed that it is a readily reversible, potent and competitive inhibitor versus a synthetic tripeptide substrate with a Ki of 0.08 nM, an association rate of 2 × 107 M−1s−1and a dissociation half life of 3.4 min. Weak affinity (Ki ~3 μM) is observed for thrombin, plasma kallikrein, and chymotrypsin. Affinity for trypsin and all other serine proteases tested is negligible with Ki > 15 μM. Apixaban is an effective inhibitor of free fXa and of prothrombinase, in buffer, platelet poor plasma, and whole blood. The anticoagulant activity of apixaban was determined in platelet-poor human plasma. Apixaban causes concentration dependent prolongation of the fXa mediated clotting assays. The human plasma concentration required to produce a doubling of the clotting time is 3.6 μM for prothrombin time, 7.4 μM for activated partial thromboplastin time and 0.4 μM for HepTest. To support preclinical efficacy and safety studies purified fXa from rabbit, dog and rat plasma was also found to be inhibited by apixaban (0.17, 2.6, and 1.3 nM, respectively). In summary the in vitro properties of apixaban show that it is a highly selective and potentially potent antithrombotic agent for venous and arterial thrombotic diseases.


2006 ◽  
Vol 100 (1) ◽  
pp. 249-257 ◽  
Author(s):  
Theodore W. Zderic ◽  
Marc T. Hamilton

Physical inactivity is a risk factor for lipoprotein disorders and the metabolic syndrome. Physical inactivity has a powerful effect on suppressing lipoprotein lipase (LPL) activity in skeletal muscle, the rate-limiting enzyme for hydrolysis of triglyceride (TG)-rich lipoproteins. We tested the ability of several compounds to prevent the decrease in LPL. The present study minimized standing and ordinary light nonexercise movements in rats to compare the effects of inactivity and nonexercise activity thermogenesis (NEAT) on LPL activity. The key new insight was that the typically quick decrease in LPL activity of oxidative muscle caused by physical inactivity was prevented by nicotinic acid (NA), whereas inhibitors of TNF-α, inducible nitric oxide synthase, and NF-κB had no such effect. NA was administered at a dose known to acutely impede the appearance of plasma TG from the liver and free fatty acids from adipose tissue, and it was effective at intentionally lowering plasma lipid concentrations to the same level in active and inactive groups. As measured from heparin-releasable LPL activity, LPL in the microvasculature of the most oxidative muscles was ∼90% lower in the inactive group compared with controls, and this suppression was completely blocked by NA. In contrast to inactivity, NA did not raise muscle LPL in ambulatory controls, whereas a large exogenous fat delivery did decrease LPL activity. In vitro control studies revealed that NA did not have a direct effect on skeletal muscle LPL activity. In conclusion, physical inactivity amplifies the ability of plasma lipids to suppress muscle LPL activity. The light ambulatory contractions responsible for NEAT are sufficient for mitigating these deleterious effects.


2015 ◽  
Vol 11 (5) ◽  
pp. 659-665
Author(s):  
Tuba Erkaya ◽  
Aykut Öztekin ◽  
Hasan Özdemir ◽  
Mustafa Şengül

Abstract Angiotensin converting enzyme (ACE)-inhibitory activity in water soluble extracts (WSEs) of kefir was investigated. Kefir was produced traditionally using kefir grains and stored at refrigerated temperature for 20 days. During storage period (on 1, 5, 10, 15 and 20 days) in vitro ACE-inhibitory activity in WSEs was determined. ACE was purified from human plasma to determine kinetic parameters. Purified ACE had a specific activity of 20.75 EU.mg−1, a yield of 16.6% with a factor of 22100. The inhibition effects of kefir on ACE increased at 15 storage days than other storage days. Some microbiological and physicochemical characteristics of kefir were also studied. Counts of presumptive LAB on M-17 and presumptive LAB on MRS in the kefir were about 108 CFU.ml−1 throughout the storage period. Yeast counts were lower than lactic acid bacteria counts and the average of the counts was approximately 106 log CFU.ml−1. Storage period had a significant effect (P < 0.05) on titratable acidity and pH values. On the contrary, it had no significant effect (P > 0.05) on viscosity and serum separation values of kefir.


2020 ◽  
Vol 150 (10) ◽  
pp. 2707-2715 ◽  
Author(s):  
Oliviero Olivieri ◽  
Giulia Speziali ◽  
Annalisa Castagna ◽  
Patrizia Pattini ◽  
Silvia Udali ◽  
...  

ABSTRACT Background In the settings of primary and secondary prevention for coronary artery disease (CAD), a crucial role is played by some key molecules involved in triglyceride (TG) metabolism, such as ApoCIII. Fatty acid (FA) intake is well recognized as a main determinant of plasma lipids, including plasma TG concentration. Objectives The aim was to investigate the possible relations between the intakes of different FAs, estimated by their plasma concentrations, and circulating amounts of ApoCIII. Methods Plasma samples were obtained from 1370 subjects with or without angiographically demonstrated CAD (mean ± SD age: 60.6 ± 11.0 y; males: 75.8%; BMI: 25.9 ± 4.6 kg/m2; CAD: 73.3%). Plasma lipid, ApoCIII, and FA concentrations were measured. Data were analyzed by regression models adjusted for FAs and other potential confounders, such as sex, age, BMI, diabetes, smoking, and lipid-lowering therapies. The in vitro effects of FAs were tested by incubating HepG2 hepatoma cells with increasing concentrations of selected FAs, and the mRNA and protein contents in the cells were quantified by real-time RT-PCR and LC-MS/MS analyses. Results Among all the analyzed FAs, myristic acid (14:0) showed the most robust correlations with both TGs (R = 0.441, P = 2.6 × 10−66) and ApoCIII (R = 0.327, P = 1.1 × 10−31). By multiple regression analysis, myristic acid was the best predictor of both plasma TG and ApoCIII variability. Plasma TG and ApoCIII concentrations increased progressively at increasing concentrations of myristic acid, independently of CAD diagnosis and gender. Consistent with these data, in the in vitro experiments, an ∼2-fold increase in the expression levels of the ApoCIII mRNA and protein was observed after incubation with 250 μM myristic acid. A weaker effect (∼30% increase) was observed for palmitic acid, whereas incubation with oleic acid did not affect ApoCIII protein or gene expression. Conclusions Plasma myristic acid is associated with increased ApoCIII concentrations in cardiovascular patients. In vitro experiments indicated that myristic acid stimulates ApoCIII expression in HepG2 cells.


1987 ◽  
Author(s):  
A Kornberg ◽  
S Kaufman ◽  
L Silber ◽  
J Ishay

The extract from the venom sac of Vespa orientalis (VSE) inactivates exogenous and endogenous thromboplastin (Joshua and Ishay, Toxicon, 13:11-20,1975). The prolongation of both prothrombin time (PT) and recalcification time suggests inactivation of other factors. The aim of the present study is to investigate the effect of VSE on clotting factors. A lyophilized VSE with protein concentration of 5 mg/ml was used. Studies were performed in vitro with human plasma and in vivo in cats. Routine methods were employed for the assay of PT, activated tissue thromboplastin (APTT), thrombin time (TT), fibrinogen degradation products (FDP), fibrinogen and factors V,VII,VIII,IX,X. Human plasma was incubated with various concentrations of VSE (0,1,5,10,50,100 μg/ml) for 60 min and for various incubation times (0,5,15,30,+ 60,90,120 min) with 50 μg/ml VSE (n=8). 1 μg/ml VSE prolonged PT from 13.5 to 16 sec (p<0.05) and APTT from 62 to 180 sec. PT was maximal (17.7 sec) with 10 μg/ml and APTT (442 sec) with 50 μg/ml VSE. Factors V,VII,X decreased gradually from 94-105% to 11%,11% and 29% with 100 μg/ml VSE and VIII and IX to 1% even with 1 μg/ml VSE. After 5 min with constant concentration of VSE (50 μg/ml) PT was 14.9 sec (normal 13 sec) and APTT 165 sec (normal 54 sec). Both were maximal (17.5 and 298 sec) after 60 min. Factors VII and X decreased to 13% and 32% and VIII and IX to >1% after 60 min of incubation. Injection of 5 mg/kg VSE to cats (n=6-8) resulted in prolongation of PT from 9.4 to 11.2 sec and of APTT from 19.5 to 63 sec after 5 min. Both were maximal after 90 min (12.3 and 127 sec). Factors V,VII and X decreased from 100% to 7.6%, 13% and 37% and VIII and IX to 1% after 10 min. In all experiments TT and plasma fibrinogen were not affected and FDP were normal. Heating of VSE for 5 min at 80°C abolished completely the anticoagulant activity but dialysis for 24 hr at 4°C had no effect on it. The activity was eluted on Sephadex-25 both in void and post void volumes. The results show that VSE has a potent anticoagulant activity against various factors. Factors VIII and IX are markedly decreased. The effect on V, VII and X is moderate. Plasma fibrinogen is not affected. The nature and clinical significance of the anticoagulant activity merit further investigation.


2011 ◽  
Vol 6 (6) ◽  
pp. 990-996 ◽  
Author(s):  
Beata Olas ◽  
Joanna Kołodziejczyk-Czepas ◽  
Barbara Wachowicz ◽  
Dariusz Jędrejek ◽  
Anna Stochmal ◽  
...  

AbstractHumulus lupulus (Cannabaceae) is well known throughout the world as a raw material in the brewing industry. The antioxidative action of hop cones is poorly understood, therefore the aim of our present study was to investigate in vitro changes in human plasma induced by peroxynitrite in the presence of the highly purified extract from hop cones (Humulus lupulus). The aim of our study was also to explain the effect of the extract from hop cones on coagulation activity of human plasma treated with peroxynitrite. The action of the extract from hop cones was compared with the properties of a well-characterized commercial monomeric polyphenol — resveratrol (3,4′,5-trihydroxystilbene). The tested plant extract, like resveratrol, significantly inhibited protein carbonylation and nitration in plasma treated with ONOO−(0.1 mM). The extract from hop cones, like resveratrol, also caused a distinct reduction of plasma lipid peroxidation induced by ONOO−. Moreover, the tested extract modulated the coagulation properties of plasma treated with peroxynitrite. It seems that antioxidative activities of the highly purified extract from hop cones may be responsible for its medicinal properties.


2005 ◽  
Vol 51 (11) ◽  
pp. 2138-2144 ◽  
Author(s):  
Mark A Atkin ◽  
Amy Gasper ◽  
Raj Ullegaddi ◽  
Hilary J Powers

Abstract Background: The susceptibility of plasma lipids to oxidation is thought to be a factor contributing to atherogenic risk. Various groups have studied the in vitro oxidizability of isolated LDL and examined the effects of conventional antioxidants. The drawbacks associated with the isolation of LDL for evaluation of in vitro oxidizability, however, have limited the application of this measurement in large-scale studies. Methods: We developed and evaluated an assay that can be used to directly assess the oxidative susceptibility of unfractionated serum or plasma lipids, obviating the need for isolation of lipoprotein fractions. Oxidative conditions were initiated in vitro with cuprous chloride and 2,2′-azobis(2-amidinopropane) hydrochloride. The effects of antioxidants added in vitro, and as an oral supplement, were monitored by conjugated diene formation. Results: The addition of ascorbic acid (0–50 μmol/L) in vitro elicited a dose-dependent protective effect, increasing the lag time to oxidation (P &lt;0.001). In contrast, α-tocopherol demonstrated prooxidant behavior at increasing concentrations (0–50 μmol/L), although we observed a decrease in the maximum rate of oxidation. Our findings are supported by the results from plasma samples of participants in a randomized antioxidant (vitamins C and E) intervention study after acute ischemic stroke. The group receiving vitamins C and E for 14 days showed an increased lag time to plasma lipid oxidation in vitro compared with the nonsupplemented group (P &lt;0.05). Conclusion: The susceptibility of unfractionated plasma or serum lipids to oxidation in vitro offers an alternative to LDL for evaluating the efficacy of antioxidant regimens.


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