Conferenze
Anti-thrombotic properties of tomatoes
12 giugno 2008
Department of Pharmacological Sciences, Unversity of Milan
Professor Asim K. Duttaroy
Department of Nutrition, Faculty of Medicine,
University of Oslo, Norway
Epidemiological studies have shown that dietary behaviour is an important aetiological factor in various chronic diseases. Tomato contains several antioxidants including lycopene, flavonoids, and trace elements, vitamins beneficial to the cardiovascular system. In addition, the presence of several anti-platelet factors in tomatoes make it ideal cardiovascular food. Modulation of platelet reactivity towards collagen, ADP and thrombin by tomato or tomato products could be of potentially prophylactic and therapeutic benefit in preventing and halting pathologic processes that lead to CVD. The search for alternative anti-platelet drugs, which are devoid of adverse side effects, continues. We investigated inhibitory effect of different fruit extracts on human platelet aggregation in vitro. The maximum inhibitory effect (70-75%) was found to be with tomato and kiwi fruit extracts whereas, apple and pear had very little activity (2-5%). Grapefruit, melon and strawberry had intermediate activities on platelet aggregation (33-44%). Most of the anti-platelet properties of tomatoes reside in the juicy part of the fruit. The anti-platelet potential of the fruits tested appeared to be opposite to that of their antioxidant activity which was reported. Tomato extract used in a dose-dependant manner inhibited ADP-induced platelet aggregation in vitro. However, tomato-derived compounds also inhibit thrombin-induced platelet aggregation.
In a randomized, double-blinded, placebo-controlled crossover a significant reductions in platelet aggregation was observed 3h after supplementation with tomato extract equivalent to two and six tomatoes. Two different extract-supplemented treatment drinks were prepared in 50- and 200-mL volumes. Each treatment drink contained 18 g tomato extract syrup, which is equivalent to the quantity of antiplatelet factors found in 6 fresh tomatoes. Inhibition of aggregation was observed for both ADP- and collagen-mediated aggregation in a dose-dependent manner. Male subjects showed greater sensitivity to the extract, as evidenced by significantly larger reductions in platelet aggregation in response to ADP or collagen, than did the female subjects. No adverse side-effects of the supplementation were reported, and no effects on clotting time variables were detected after supplementation. Our data provides evidence that tomato extracts have great potential for increasing the effectiveness of thrombosis prophylaxis through an oral tomato extract therapy. Modulation of platelet reactivity towards collagen, ADP and thrombin by tomato extract could be of potentially prophylactic and therapeutic benefit in preventing and halting pathologic processes that lead to CVD.
References:
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Duttaroy AK, Crosbie L, Gordon MJ. Effects of tomato extract on human platelet aggregation in vitro. Platelets 2001; 12: 218-27.
O'Kennedy N, Crosbie L, van LM, Broom JI, Webb DJ, Duttaroy AK. Effects of antiplatelet components of tomato extract on platelet function in vitro and ex vivo: a time-course cannulation study in healthy humans. American Journal of Clinical Nutrition 2006; 84: 570-9.
O'Kennedy N, Crosbie L, Whelan S, Luther V, Horgan G, Broom JI et al. Effects of tomato extract on platelet function: a double-blinded crossover study in healthy humans. American Journal of Clinical Nutrition 2006; 84: 561-9.
