Antithrombotic effect of onion in streptozotocin-induced diabetic rat

In the present study, we investigated whether onion has antithrombotic effect in streptozotocin (STZ)-induced diabetic rats. In diabetic rats, serum thromboxane B2 (TXB2) level was elevated compared to that in normal, and this elevation in diabetes was significantly inhibited by treatment with onion (0.5 g/ml/kg/day, i.p.) for 4 weeks. In normal rats, the serum TXB2 level remained unaltered after the treatment with onion. To investigate in vitro effect of onion, we examined its effect on TXB2 formation, platelet aggregation and arachidonic acid (AA)-release in platelets from diabetic and normal rats. Onion showed a significant inhibitory effect on collagen- or AA-induced TXB2 formation with greater potency in diabetic platelets than in normal. Similarly, more potent inhibitory effects of onion in diabetes were observed in collagen- or AA-induced platelet aggregation and collagen-induced AA release response. In conclusion, these results suggest that onion can produce more beneficial antithrombotic effect in diabetes.