title: Anti-platelet effects of olive oil extract: in vitro functional and proteomic studies.
abstract: OBJECTIVE
  Platelets play a key role in haemostasis and wound healing, contributing to formation of vascular plugs. They are also involved in formation of atherosclerosic plaques. Some traditional diets, like the Mediterranean diet, are associated with a lower risk of cardiovascular disease. Components in these diets may have anti-platelet functions contributing to their health benefits.
  
  
  METHODS
  We studied the effects of alperujo extract, an olive oil production waste product containing the majority of polyphenols found in olive fruits, through measurement of effects on platelet aggregation and activation in isolated human platelets, and through identification of changes in the platelet proteome.
  
  
  RESULTS
  Alperujo extract (40 mg/L) significantly decreased in vitro ADP- (p = 0.002) and TRAP- (p = 0.02) induced platelet activation as measured by the flow cytometry using the antibody for p-selectin (CD62p), but it did not affect the conformation of the fibrinogen receptor as measured by flow cytometry using the antibodies for anti-fibrinogen, CD42a and CD42b. Alperujo extract (100 mg/L) inhibited both collagen- and TRAP-induced platelet aggregation by 5% (p < 0.05), and a combination of hydroxytyrosol and 3,4-dihydroxyphenylglycol were, at least partly, responsible for this effect. Proteomic analysis identified nine proteins that were differentially regulated by the alperujo extract upon ADP-induced platelet aggregation. These proteins represent important mechanisms that may underlie the anti-platelet effects of this extract: regulation of platelet structure and aggregation, coagulation and apoptosis, and signalling by integrin αIIb/β3.
  
  
  CONCLUSIONS
  Alperujo extract may protect against platelet activation, platelet adhesion and possibly have anti-inflammatory properties.
authors.affiliation: Rowett Institute of Nutrition & Health, University of Aberdeen, Greenburn Road, Bucksburn, Aberdeen, AB21 9SB, UK. b.deroos@abdn.ac.uk
authors.forename: Baukje
authors.initials: B
authors.lastname: de Roos
authors.forename: Xuguang
authors.initials: X
authors.lastname: Zhang
authors.forename: Guillermo
authors.initials: G
authors.lastname: Rodriguez Gutierrez
authors.forename: Sharon
authors.initials: S
authors.lastname: Wood
authors.forename: Garry J
authors.initials: GJ
authors.lastname: Rucklidge
authors.forename: Martin D
authors.initials: MD
authors.lastname: Reid
authors.forename: Gary J
authors.initials: GJ
authors.lastname: Duncan
authors.forename: Louise L
authors.initials: LL
authors.lastname: Cantlay
authors.forename: Garry G
authors.initials: GG
authors.lastname: Duthie
authors.forename: Niamh
authors.initials: N
authors.lastname: O'Kennedy
mesh_terms: D000906:Antibodies; D001777:Blood Coagulation / Q000187:drug effects; D001792:Blood Platelets / Q000187:drug effects*; D003094:Collagen / Q000378:metabolism; D005260:Female; D005340:Fibrinogen / Q000187:drug effects; D006801:Humans; D008297:Male; D008734:Methoxyhydroxyphenylglycol / Q000031:analogs & derivatives / Q000378:metabolism; D000069463:Olive Oil; D019007:P-Selectin / Q000187:drug effects; D010626:Phenylethyl Alcohol / Q000031:analogs & derivatives / Q000378:metabolism; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology*; D010938:Plant Oils / Q000494:pharmacology*; D010973:Platelet Adhesiveness / Q000187:drug effects; D010974:Platelet Aggregation / Q000187:drug effects; D019038:Platelet Glycoprotein GPIb-IX Complex / Q000378:metabolism; D059808:Polyphenols / Q000494:pharmacology*; D040901:Proteomics / Q000379:methods*
chemical_list: D000906:Antibodies; D000069463:Olive Oil; D019007:P-Selectin; D010936:Plant Extracts; D010938:Plant Oils; D019038:Platelet Glycoprotein GPIb-IX Complex; D059808:Polyphenols; C005975:3,4-dihydroxyphenylethanol; D008734:Methoxyhydroxyphenylglycol; D005340:Fibrinogen; D003094:Collagen; D010626:Phenylethyl Alcohol; C010117:3,4-dihydroxyphenylglycol