In vitro effect of trichosanic acid, a major component of Trichosanthes japonica on platelet aggregation and arachidonic acid metabolism in human platelets

1988 ◽  
Vol 31 (2) ◽  
pp. 65-72 ◽  
Author(s):  
Mitsuko Takenaga ◽  
Aizan Hirai ◽  
Takashi Terano ◽  
Yasushi Tamura ◽  
Haruo Kitagawa ◽  
...  
Keyword(s):  
Arachidonic Acid ◽  
Platelet Aggregation ◽  
Acid Metabolism ◽  
Human Platelets ◽  
Arachidonic Acid Metabolism ◽  
Vitro Effect

Influence of certain compounds of plant origin on platelet aggregation and arachidonic acid metabolism in human platelets

1986 ◽  
Vol 20 (10) ◽  
pp. 740-744
Author(s):  
A. G. Panosyan ◽  
A. G. Aivazyan ◽  
M. L. Barikyan ◽  
G. A. Gevorkyan ◽  
G. G. Zapesochnaya ◽  
...  
Keyword(s):  
Arachidonic Acid ◽  
Platelet Aggregation ◽  
Acid Metabolism ◽  
Human Platelets ◽  
Arachidonic Acid Metabolism ◽  
Plant Origin

Glutathione Peroxidase And Malondialdehyde Production In The Arachidonic Acid Metabolism Of Human Platelets

1981 ◽  
Author(s):  
G C Guidi ◽  
R Schiavon ◽  
G L Avventi ◽  
G Perona
Keyword(s):  
Arachidonic Acid ◽  
Glutathione Peroxidase ◽  
Peroxidase Activity ◽  
Acid Metabolism ◽  
Inverse Correlation ◽  
Human Platelets ◽  
Arachidonic Acid Metabolism ◽  
Glutathione Peroxidase Activity ◽  
Physiological Variations

A series of functional parameters, including the aggregability triggered by various agents, the in vitro malondialdehyde production and the glutathio ne peroxidase activity, has been investigated in platelets from normal blood donors.Glutathione peroxidase activity assays showed a significant inverse correlation with malondialdehyde induced by arachidonic acid but not with aggregation data and malondialdehyde induced by thrombin. Moreover, arachidonic acid generates in human platelets lysates large amounts of hydrogen acceptor substrate(s) for the glutathione peroxidase with peculiar kinetic features. These are related to ma londialdehyde production and to partial inhibition by acetyl-salicilic acid and are likely connected with prostaglandin metabolism.Our data suggest that physiological variations in glutathione peroxidase activity are important in human platelet arachidonic acid metabolism, because they modulate the biosynthesis of key end-products, as thromboxane A2, whose malondialdehyde is an inde.

In Vitro Effect Of Ticlopidine On Arachidonic Acid Metabolism In Platelet Phospholipids

1981 ◽  
Author(s):  
H Chap ◽  
M F Simon ◽  
L Douste-Blazy
Keyword(s):  
Arachidonic Acid ◽  
Acid Metabolism ◽  
Arachidonic Acid Metabolism ◽  
Maximum Effect ◽  
Prostaglandin D2 ◽  
Intact Cells ◽  
Vitro Effect ◽  
Slight Inhibition ◽  
Acylation Reactions

The effects of ticlopidine (Ti) on arachidonic acid (AA) metabolism in platelet phospholipids have been studied in vitro by following AA release from (14C) AA-prelabeled platelets or by measuring (14C)-AA incorporation into platelet phospholipids.In the presence of prelabeled platelets, Ti induced a release of AA essentially from phosphatidylcholine (PC) only at concentrations (10-3 M) where the drug became lytic. Incubation of cells previously lysed by sonication led to a deacylation of PC, part of the released AA being reincorporated into phosphatidylethanolamine (PE) . Under these conditions, Ti effect on PC disappeared and only a slight inhibition of AA incorporation into PE was observed.On the other hand, upon incubation of non-labeled platelets with (14C)-AA, Ti impaired the incorporation of AA into all platelet phospholipids, half maximum effect being observed under non-lytic conditions at 10-5-5.10-5 M.It is postulated that Ti inhibits the acylation reactions responsible for AA entry into glycerophospholipids. This effect might promote the release of trace amounts of AA in intact cells, which could explain the accumulation of stable, anti-aggregating prostaglandin D2 (M. Lagarde et al. Prostagl. Med. 1979, 2, 433).

In Vitro Incorporation and Metabolism of Icosapentaenoic and Docosahexaenoic Acids in Human Platelets - Effect on Aggregation

1986 ◽  
Vol 56 (01) ◽  
pp. 057-062 ◽  
Author(s):  
Martine Croset ◽  
M Lagarde
Keyword(s):  
Arachidonic Acid ◽  
Fatty Acid ◽  
Platelet Aggregation ◽  
Fatty Acid Distribution ◽  
Thromboxane A2 ◽  
Human Platelets ◽  
Aggregation Response ◽  
Docosahexaenoic Acids ◽  
Membrane Level

SummaryWashed human platelets were pre-loaded with icosapentaenoic acid (EPA), docosahexaenoic acid (DHA) or EPA + DHA and tested for their aggregation response in comparison with control platelets. In fatty acid-rich platelets, an inhibition of the aggregation could be observed when induced by thrombin, collagen or U-46619. The strongest inhibition was observed with DHA-rich platelets and it was reduced when DHA was incorporated in the presence of EPA.Study of fatty acid distribution in cell lipids after loading showed that around 90% of EPA or DHA taken up was acylated into phospholipids and a very small amount (less than 2%) remained in their free and hydroxylated forms. DHA was more efficiently acylated into phosphatidylethanolamine (PE) than into phosphatidylinositol (PI) in contrast to what observed with EPA, and both acids were preferentially incorporated into phosphatidylcholine (PC). EPA inhibited total incorporation of DHA and increased its relative acylation into PE at the expense of PC. In contrast, DHA did not affect the acylation of EPA. Upon stimulation with, thrombin, EPA was liberated from phospholipids and oxygenated (as judged by the formation of its monohydroxy derivative) whereas DHA was much less metabolized, although consistently transferred into PE.It is concluded that EPA and DHA might affect platelet aggregation via different mechanisms when pre-loaded in phospholipids. Whereas EPA is known to alter thromboxane A2 metabolism from endogenous arachidonic acid, by competing with it, DHA might act directly at the membrane level for inhibiting aggregation.

Sign in / Sign up

Export Citation Format

Share Document