Propolis ethanolic extracts reduce adenosine diphosphate induced platelet aggregation determined on whole blood

Abstract

BackgroundPropolis is a well-known bee product containing more than 2000 identified compounds. It has many beneficial effects on human health that include antibacterial, antiviral, anticancer and hepatoprotective justifying its use as a dietary supplement. Platelet aggregation plays crucial role in thrombus formation that can cause stroke or heart attacks. As cardiovascular diseases, including those caused by thrombus formation, are related to 50% of deaths of Western population, the objective of this study was to determine antiaggregatory activity of propolis on platelet aggregation on the whole blood samples.MethodsTwenty one propolis samples from Southeast Europe were characterized by spectrophotometric methods to determine content of the total flavonoids and phenolic acids. High performance liquid chromatography coupled with diode array detection was used to identify and quantify individual polyphenols. Platelet aggregation was tested by impedance aggregometry on the whole blood samples of ten healthy volunteers.ResultsThe mean content of total polyphenols was 136.14 mg/g and ranged from 59.23 to 277.39 mg/g. Content of total flavonoids ranged between 6.83 and 55.44 mg/g with the mean value of 19.28 mg/g. Percentage of total phenolic acids was in the range 8.79 to 45.67% (mean 26.63%). Minimal antiaggregatory concentration, representing the lowest concentration of propolis extract sample that can cause statistically significant reduction of aggregation, ranged from 5 μM to 10.4 mM. Samples of propolis with lower content of luteolin and higher content of pinocembrin-7-methyleter showed better antiplatelet activity i.e. lower values of minimal antiaggregatory concentration.ConclusionsThis is the first study that shows antiaggregatory potential of propolis ethanolic extracts on the whole blood samples in the low micromolar concentrations suggesting that propolis supplementation may influence platelet aggregation and consequently thrombus formation. Further in vivo studies are needed to confirm the beneficial effects in prevention of cardiovascular diseases.

Polyphenols: Modulators of Platelet Function and Platelet Microparticle Generation?

“…The inhibition of the COX-1 pathway appears to be the most common. However, with the study by Bojic et al [71], the inhibition of the P2Y 12 pathway of activation may result in a decrease in the expression of the GPIIb/IIIa receptor which is involved in crosslinking activated platelets to form platelet aggregates [72]. Overall, however, the rich source of flavonoid and phenolic acids together in propolis may highlight a synergistic anti-aggregatory effect.…”

“…Using whole blood impedance, another study evaluated the antiplatelet benefit of polyphenol-rich product propolis. Bojic et al [71] demonstrated that propolis inhibited ADP-induced platelet aggregation in whole blood. The study measured the anti-aggregatory effect of propolis ethanolic extracts in whole blood.…”

“…Randomized single blind study. Evaluation of inhibition of platelet aggregation and ATP release by olive leaf extract polyphenols Agg Significant dose-dependent inhibition of aggregation and ATP release [59] In vitro Grape seed extract 5 healthy subjects TRAP and thrombin-induced activation of gel filtered platelets to compare antiplatelet property of GSE (1.25-50 µg mL −1 ) with pure resveratrol Both Inhibition of TRAP and thrombin-induced P-selectin expression, PMP formation, platelet aggregation, and superoxide anion radicals generated from platelets in a dose-dependent manner [81] In vitro Propolis 10 healthy subjects ADP-induced platelet aggregation to evaluate inhibition 21 propolis polyphenolic extracts Agg Most potent inhibitor of aggregation contained luteolin, apigenin, and chrysin [71] In vitro…”

Insight on Propolis from Mediterranean Countries: Chemical Composition, Biological Activities and Application Fields

“…Other researchers, [235] more recently, checked different propolis samples from Croatia regarding their anti-aggregatory activity on platelet aggregation, and demonstrated that propolis even in low concentrations presented an important anti-aggregatory potential, suggesting that propolis supplementation may influence platelet aggregation, which can play crucial role in thrombus formation responsible of stroke or heart attacks. Moreover, Barbarić et al [68] studied propolis samples from Bosnia and Hercegovina and Croatia regarding its cytotoxic effects on cervical tumor cell line (HeLa), and they found that it exhibited an antiproliferative and cytotoxic effect.…”

Development and validation of a sensitive and specific LC–MS/MS cocktail assay for CYP450 enzymes: Application to study the effect of catechin on rat hepatic CYP activity

“…Research in the past decade has demonstrated several health benefits of flavonoids (Kozłowska & Szostak‐Węgierek, ). The mechanisms underlying these health benefits include, but are not limited to, anti‐inflammation, antioxidation, antimicrobial, and antimutagenic effects (Bojić, Antolić, Tomičić, Debeljak, & Maleš, ). Flavonoids are susceptible to CYP metabolism; however, they can also act as enzyme inhibitors and cause clinically significant interactions (Östlund, ).…”