Effects of bioactive-rich extracts of pomegranate, persimmon, nettle, dill, kale and Sideritis and isolated bioactives on arachidonic acid induced markers of platelet activation and aggregation (original) (raw)
Related papers
Journal of the Science of Food and Agriculture, 2013
BACKGROUND: The health benefits of fruit and vegetable-rich diets may be partly due to modulation of platelet activity by bioactive phytochemicals. The aim of this study was to investigate the effects of bioactive-rich plant extracts and isolated bioactive metabolites on platelet function. Blood samples (n =15 subjects) were treated with extracts of bioactive-rich plants consumed as traditional foods in the Black Sea region, or with human metabolites of the bioactives quercetin and sulforaphane. Platelet function was assessed using the PFA-100. RESULTS: None of the extracts containing various flavonoids, glucosinolates and other bioactives, or isolated bioactive metabolites of quercetin or sulforaphane, caused significant changes in PFA-100 closure time (CT). In contrast, the positive controls (aspirin and Abciximab) consistently caused significant increases in CT for the platelet agonists epinephrine and ADP, respectively. CONCLUSION: These data do not support the notion that these plant bioactives can improve human platelet function.
Inhibitory effect of aqueous extracts of some herbs on human platelet aggregation in vitro
Platelets, 2005
Effect of aqueous extract of several herbs on human platelet aggregation in vitro was investigated. Out of 28 herbs/ nutriceuticals investigated, camomile, nettle alfalfa, garlic and onion exhibited most significant anti-platelet activity (!45% inhibition). Aqueous extracts of alfalfa, fresh nettle, and camomile inhibited ADP induced-platelet aggregation by 73, 65 and 60%, respectively, compared with control (P < 0.05). Camomile and alfalfa inhibited collagen-induced platelet aggregation by 84 and 65%, respectively, but nettle could not inhibit collagen-induced aggregation. In contrast, nettle was the most potent inhibitor (66%) of whole blood aggregation induced by collagen, followed by alfalfa (52%), and camomile (30%) compared with control (P < 0.05). None of these three herbs however could inhibit arachidonic acid or thrombin induced platelet aggregation. Camomile and alfalfa strongly inhibited thromboxane B 2 synthesis induced by ADP or collagen, but nettle had no effect. Alfalfa and nettle increased cGMP levels in platelets by 50 and 35%, respectively, compared with the control (1.85 AE 0.23 nM) (P < 0.005). All these data indicate that camomile, nettle and alfalfa have potent anti-platelet properties, and their inhibitory actions are mediated via different mechanisms.
Platelets, 2008
The aim of the present study was to investigate and compare the anti-platelet action of extracts from three different plants: bark of Yucca schidigera, seeds of grape and berries of Aronia melanocarpa (chokeberry). Anti-platelet action of tested extracts was compared with action of well characterized antioxidative and anti-platelet commercial monomeric polyphenol-resveratrol. The effects of extracts on platelet adhesion to collagen, collagen-induced platelet aggregation and on the production of O À 2 in resting platelets and platelets stimulated by a strong platelet agonist-thrombin were studied. The in vitro experiments have shown that all three tested extracts (5-50 mg/ml) rich in polyphenols reduce platelet adhesion, aggregation and generation of O À 2 in blood platelets. Comparative studies indicate that all three plant extracts were found to be more reactive in reduction of platelet processes than the solution of pure resveratrol. The tested extracts due to their anti-platelet effects may play an important role as components of human diet in prevention of cardiovascular or inflammatory diseases, where blood platelets are involved.
Oxidative pathways of arachidonic acid as targets for regulation of platelet activation
Prostaglandins & Other Lipid Mediators, 2019
This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Role of arachidonic acid metabolism in human platelet activation and irreversible aggregation
American Journal of Hematology, 1985
Previous studies from our laboratory have demonstrated that the aggregation response of platelets inhibited by agents blocking cyclooxygenase activity could be restored to a normal state of sensitivity by prior stimulation of a-adrenergic receptors. Since cyclooxygenase activity and thromboxane synthesis are not absolutely required for irreversible platelet aggregation, it is important to define precisely what role this pathway serves in platelet physiology. The present study has evaluated the influence of agents that selectively block arachidonic acid conversion at different steps of synthesis. Inhibition of peroxidase, cyclooxygenase, lipoxygenase, and thromboxane synthetase blocked the second wave response of platelets to several agonists, but did not cause dissociation of aggregates preformed by prior exposure to arachidonate (AA) or adenosine diphosphate. Phospholipase (A*/C) inhibitors, similar to prostaglandin inhibitors, blocked the second wave response of platelets to the action of agonists and, in addition, caused dissociation of aggregates induced by aggregating agents. Results of our study demonstrate that when single agonists are tested at threshold concentrations, products of arachidonate metabolism may play a role in the activation process. However, continued generation of these metabolites does not appear to be essential for the maintenance of irreversible aggregation. When a combination of agents or high concentration of physiological agonists are used, both activation and irreversible aggregation can be secured independent of prostaglandin synthesis or the release reaction.
The effects of polyphenols in olive leaves on platelet function
Nutrition Metabolism and Cardiovascular Diseases, 2008
Introduction: The phenolic compounds of olive leaves and olive oils in the Mediterranean diet have been associated with a reduced incidence of heart disease. Accordingly, antioxidant-rich diets may prevent the deleterious effects of oxidative metabolism by scavenging free radicals, thus inhibiting oxidation and delaying atherosclerosis. The process involves phospholipase C activation and arachidonic acid metabolism, and is thought to reduce hydrogen peroxide (H 2 O 2 ). In our study, an extract of Olea europaea L. leaves was used. The active phenolic compounds in this extract are part of the secoiridoid family, known for their capacity to scavenge H 2 O 2 . The results from this study will help to improve our understanding of effects of polyphenol antioxidants in olive leaf extract on platelet function. Methods: Full blood examination (FBE), platelet aggregation, and ATP release were performed on samples from fasting, normal, healthy male subjects. Platelet function at increasing concentrations of oleuropein was investigated through measures of platelet aggregation and ATP release from activated platelets. Results: Blood analysis (n [ 11) revealed a significant dose-dependant reduction in platelet activity with olive extract concentrations of 1.0% v/v (P < 0.001). ATP Release showed a similar pattern (P [ 0.02). Conclusions: Olive leaf polyphenols derived from O. europaea L. leaves inhibited in vitro platelet activation in healthy, non-smoking males. Further bioavailability studies need to be undertaken to determine the in vivo effect of extract on platelet function and to validate the present results. ª
p-Coumaric acid, a common dietary phenol, inhibits platelet activity in vitro and in vivo
British Journal of Nutrition, 2007
p-Coumaric acid (3-(4-hydroxyphenyl)-2-propenoic acid; 4CA), is a ubiquitous plant metabolite with antioxidant and anti-inflammatory properties. The antiplatelet activity of this compound was analysed both ex vivo and in vitro. 4-CA, administered to rabbits for 2 weeks at the dose of 5 mg/kg, mixed with food, inhibited ADP-induced platelet aggregation without affecting blood coagulation. This effect was associated with a marked increase in plasma antioxidant activity, measured as ferric reducing ability of plasma, and with the reduction of thromboxane B 2 production. The antiplatelet effect was confirmed by in vitro experiments on human blood: 4CA (500 mM and 1 mM) reduced ADP-induced platelet aggregation (55·2 (SE 4·01) % and 35·6 (SE 2·35) % relative to basal level, respectively). 4CA was able to modify platelet function, measured with PFA-100e, a shear-inducing device that simulates primary haemostasis. 4CA interfered also with arachidonic acid cascade, reducing thromboxane B 2 production and lipopolysaccharide-induced prostaglandin E 2 generation (IC 50 371 and 126 mM, respectively). The data show that 4CA is an antioxidant compound with good antiplatelet activity at doses that can be obtained with dietary intervention, suggesting possible applications for primary prevention of vascular disease.
American Journal of Therapeutics, 2016
The purpose of this study was to evaluate the effect of the consumption of seed oils from Vitis vinifera and Arachis hypogaea in platelet aggregation. The initial hypothesis suggested that subjects who have consumed these seed oils undergo modified platelet aggregation. This study was performed using a pre-post test design, with a control group, and double blind. The effects of the consumption of grape seed and peanut oils were measured for platelet aggregation in clinical and laboratory tests in 30 healthy subjects. In addition to this group, a control group of 4 health subjects received no treatment with oils, just 500 mg oral administration acetylsalicylic acid for 7 days. Platelet aggregation was assessed by the Born turbidimetric method, using 3 different concentrations of adenosine diphosphate as agonists (2, 54; 1, 17; and 0, 58 mM). The study subjects had very similar results; both oils were shown to have a significant reduction in platelet aggregation. Grape seed oil showed a decrease of 8.4 6 1% in aggregation, compared with peanut oil, which decreased aggregation by 10.4 6 1%. The control group, taking 500 mg OD aspirin for 7 days, showed a significant decrease in platelet aggregation, similar to that of oil ingestion. Each of the oils was analyzed for fatty acids, to determine which particular acids were presents in greater levels, which could explain the reduction in platelet aggregation. The oil found to be most abundant in grape seeds was linoleic acid (omega-6), and in peanuts, it was oleic acid (omega-9). However, in fact, both acids reduced platelet aggregation. Consumption of plant oils from grape seeds and peanuts had a lowering effect on platelet aggregation, in addition to containing a high content of unsaturated fatty acids. However, omega-3, omega-6, and omega-9 fatty acids were not specifically responsible for the reductions mentioned above.