Vitamin E potentiates the antiplatelet activity of aspirin in collagen-stimulated platelets.
OBJECTIVE
The combination of vitamin E with aspirin is becoming an attractive therapeutic approach to prevent thrombotic vascular accidents. In this study we investigated the capacity of vitamin E (50 and 100 M) to enhance the antiplatelet effect of aspirin.


METHODS
The dose-response curves of platelet aggregation, dense body secretion, phospholipase C activation and calcium mobilization were measured in aspirin-treated platelets with and without added vitamin E (50 and 100 M). The role of vitamin E in reducing platelet adhesion to collagen was also studied.


RESULTS
We demonstrated that, in platelets incubated with 100 M vitamin E, collagen-concentration ( g/mL) able to induce 50% of the maximal platelet aggregation and of the calcium mobilization was higher than in controls (11.6 versus 3.8 and 21.3 versus 9.8, respectively). Furthermore, 50 M vitamin E reduced platelet adhesion to collagen by about 80%.


CONCLUSIONS
These data demonstrate that vitamin E can potentiate the antiplatelet activity of aspirin by inhibiting the early events of platelet activation pathways induced by collagen. This finding provides a rationale for combining aspirin and vitamin E to prevent thrombotic complications in atherosclerotic patients.
Celestini
Andrea
A
Dept. of Experimental Medicine and Pathology, University La Sapienza, Rome, Italy.
Pulcinelli
Fabio M
FM
Pignatelli
Pasquale
P
Lenti
Luisa
L
Frati
Giacomo
G
Gazzaniga
Pier Paolo
PP
Violi
Francesco
F
D001241:Aspirin / Q000494:pharmacology*; D001792:Blood Platelets / Q000166:cytology / Q000187:drug effects; D003094:Collagen / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D006801:Humans; D015539:Platelet Activation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D014810:Vitamin E / Q000494:pharmacology*
D010975:Platelet Aggregation Inhibitors; D014810:Vitamin E; D003094:Collagen; D001241:Aspirin