title: 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.
authors.affiliation: a Department of Haemostasis and Haemostatic Disorders , Medical University of Lodz , Lodz , Poland.
authors.forename: Dominika
authors.initials: D
authors.lastname: Dudzinska
authors.affiliation: b Laboratory of Experimental Immunology, Institute of Medical Biology, Polish Academy of Sciences , Lodz , Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Bednarska
authors.affiliation: a Department of Haemostasis and Haemostatic Disorders , Medical University of Lodz , Lodz , Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Boncler
authors.affiliation: a Department of Haemostasis and Haemostatic Disorders , Medical University of Lodz , Lodz , Poland.
authors.forename: Boguslawa
authors.initials: B
authors.lastname: Luzak
authors.affiliation: a Department of Haemostasis and Haemostatic Disorders , Medical University of Lodz , Lodz , Poland.
authors.forename: Cezary
authors.initials: C
authors.lastname: Watala
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D015415:Biomarkers; D001792:Blood Platelets / Q000187:drug effects* / Q000378:metabolism*; D002450:Cell Communication / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D007958:Leukocyte Count; D009504:Neutrophils / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D010766:Phosphorylation; D010936:Plant Extracts / Q000494:pharmacology*; D015539:Platelet Activation / Q000187:drug effects; D010974:Platelet Aggregation / Q000187:drug effects*; D017382:Reactive Oxygen Species / Q000378:metabolism; D016897:Respiratory Burst / Q000187:drug effects / Q000276:immunology; D065856:Rubus / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D010936:Plant Extracts; D017382:Reactive Oxygen Species
keywords: Neutrophils; Rubus caesius; Rubus idaeus; plant extracts; platelet aggregation; platelets