The influence of Rubus idaeus and Rubus caesius leaf extracts on platelet aggregation in whole blood. Cross-talk of platelets and neutrophils

Abstract

Recently, polyphenols have gained attention as potential natural cardioprotective therapeutics, due to their antiplatelet, anti-inflammatory and anticoagulant activity. Species belonging to the genus Rubus sp. have been reported to be a source of polyphenolic compounds with antioxidative proprieties and beneficial biological activities. This study investigates the effects of leaf extracts obtained from red raspberry (Rubus idaeus L.) and European dewberry (Rubus caesius L.) on the reactivity of blood platelets.

In ADP-stimulated blood, raspberry and dewberry extracts (15 µg/ml) markedly decreased platelet surface membrane expression of activated GPIIbIIIa receptor by 16% and 21%, respectively (P < 0.01) and significantly inhibited platelet aggregation (by 31–41% for raspberry and by 38–55% for dewberry, P < 0.01). In platelet-rich plasma (PRP), the extracts had no effect on ADP-induced platelet aggregation.

The effectiveness of the extracts in whole blood and the lack of their activity in PRP indicate that leukocytes are likely to participate in the platelet response to the extracts. Our experiments show that the extracts significantly reduced the amount of free radicals released by activated neutrophils in whole blood (P < 0.001), as well as in suspensions of isolated neutrophils (P < 0.05). Moreover, the reduced number of neutrophils leads to the decreased efficiency of the extracts in the inhibition of platelet aggregation. In summary, our findings show that the raspberry and dewberry leaf extracts considerably modulated blood platelet reactivity in whole blood: they influenced blood platelet aggregation, possibly via the modulation of the redox status dependent on the oxidative activity of neutrophils.

Keywords:

• Neutrophils
• plant extracts
• platelets
• platelet aggregation
• Rubus caesius
• Rubus idaeus

Acknowledgements

We are greatly indebted to Professor Zofia Sulowska from the Institute of Medical Biology PAS (Poland) for her valuable critical reading of the manuscript and Dr Joanna Rywaniak from Medical University of Lodz (Poland) for her technical support.

Declaration of interest

This work was supported by Medical University of Lodz grant no. 502-03/6-020-01/502-64-047 and the grant “Production of polyphenol extracts of plant origin with antiplatelet and cardioprotective properties – FLAWOPIRYNA” UDA-POIG.01.03.01-10-129/08-00, co-financed by the European Union from the European Regional Development Fund within the framework of the Innovative Economy Operational Programme.

On behalf of all authors, the corresponding author states that there is no conflict of interest.

Supplemental material

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