title: EPA, but not DHA, decreases mean platelet volume in normal subjects.
abstract: The first indication of platelet activation is an increase in mean platelet volume (MPV). n-3 FA are known to inhibit platelet function and to reduce the risk for coronary heart disease. The purpose of this study was to determine the effects of EPA and DHA on MPV. Healthy subjects received olive oil placebo for 4 wk and then were randomly assigned to receive 4 g of ethyl esters of either safflower oil (n = 11), EPA (n = 10), or DHA (n = 12) for 4 wk. At the end of placebo run-in and treatment periods, MPV (fL; mean +/- SEM) and platelet count (PLT-CT; 10(3)/microL blood) were measured in the basal state and after ex vivo stimulation with collagen (10 microg/mL), cold (4 degrees C), and heat (37 degrees C). Unlike DHA, EPA lowered MPV as compared with safflower oil (7.2 +/- 0.1 vs. 7.5 +/- 0.1 fL; P < 0.05) and raised PLT-CT (211 +/- 18 vs.192 +/- 18 10(3)/microL; P < 0.05) in the fasting state. Collagen and cold significantly increased MPV whereas heat lowered MPV regardless of treatment. All stimuli decreased PLT-CT. EPA significantly increased platelet EPA (0.2 +/- 0.1 vs. 3.3 +/- 0.4%) and docosapentaenoic acid (DPA; 2.2 +/- 0.3 vs. 2.9 +/- 0.3%) concentrations, but not DHA. DHA treatment significantly increased DHA (1.4 +/- 0.2 vs. 4.1 +/- 0.5%) and DPA (2.0 +/- 0.4 vs. 3.0 +/- 0.4%) concentrations, but not EPA. In conclusion, EPA, but not DHA, reduces platelet activation, an early step in platelet aggregation.
authors.affiliation: Department of Medicine, University of Missouri-Kansas City, Missouri 64108, USA.
authors.forename: Yongsoon
authors.initials: Y
authors.lastname: Park
authors.forename: William
authors.initials: W
authors.lastname: Harris
mesh_terms: D000284:Administration, Oral; D000328:Adult; D001792:Blood Platelets / Q000166:cytology / Q000187:drug effects*; D001810:Blood Volume / Q000187:drug effects*; D003094:Collagen / Q000494:pharmacology; D004281:Docosahexaenoic Acids / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D015118:Eicosapentaenoic Acid / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008297:Male; D010938:Plant Oils / Q000494:pharmacology; D015539:Platelet Activation / Q000187:drug effects; D016037:Single-Blind Method; D013696:Temperature; D013997:Time Factors
chemical_list: D010938:Plant Oils; D004281:Docosahexaenoic Acids; D003094:Collagen; D015118:Eicosapentaenoic Acid