Effects of tomato extract on platelet function: a double-blinded crossover study in healthy humans.
BACKGROUND
Aqueous extracts from tomatoes display a range of antiplatelet activities in vitro. We previously showed that the active components also alter ex vivo platelet function in persons with a high response to ADP agonist.


OBJECTIVE
The objective was to evaluate the suitability of a tomato extract for use as a dietary supplement to prevent platelet activation.


METHODS
A randomized, double-blinded, placebo-controlled crossover study was conducted in 90 healthy human subjects selected for normal platelet function. Changes from baseline hemostatic function were measured 3 h after consumption of extract-enriched or control supplements.


RESULTS
Significant reductions in ex vivo platelet aggregation induced by ADP and collagen were observed 3 h after supplementation with doses of tomato extract equivalent to 6 (6TE) and 2 (2TE) tomatoes [3 micromol ADP/L: 6TE (high dose), -21.3%; 2TE (low dose), -12.7%; P < 0.001; 7.5 micromol ADP/L: 6TE, -7.8%, 2TE, -7.6%; P < 0.001; 3 mg collagen/L: 6TE, -17.5%; 2TE, -14.6%; P = 0.007]. No significant effects were observed for control supplements. A dose response to tomato extract was found at low levels of platelet stimulation. Inhibition of platelet function was greatest in a subgroup with the highest plasma homocysteine (P < 0.05) and C-reactive protein concentrations (P < 0.001).


CONCLUSIONS
As a functional food or dietary supplement, tomato extract may have a role in primary prevention of cardiovascular disease by reducing platelet activation, which could contribute to a reduction in thrombotic events.
O'Kennedy
Niamh
N
Provexis plc, The Rowett Research Institute, Aberdeen, United Kingdom. niamh.okennedy@provexis.com
Crosbie
Lynn
L
Whelan
Stuart
S
Luther
Vanessa
V
Horgan
Graham
G
Broom
John I
JI
Webb
David J
DJ
Duttaroy
Asim K
AK
D000368:Aged; D001792:Blood Platelets / Q000187:drug effects / Q000502:physiology*; D002318:Cardiovascular Diseases / Q000097:blood / Q000517:prevention & control; D018592:Cross-Over Studies; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D005343:Fibrinolytic Agents / Q000494:pharmacology*; D006801:Humans; D018551:Solanum lycopersicum / Q000737:chemistry*; D008297:Male; D008875:Middle Aged; D010936:Plant Extracts / Q000494:pharmacology; D015539:Platelet Activation / Q000187:drug effects* / Q000502:physiology; D010974:Platelet Aggregation / Q000187:drug effects* / Q000502:physiology; D010979:Platelet Function Tests; D013927:Thrombosis / Q000097:blood / Q000517:prevention & control; D013997:Time Factors
D005343:Fibrinolytic Agents; D010936:Plant Extracts