Inhibitory action of glucosamine on platelet activation in guinea pigs.

OBJECTIVE

Glucosamine, a naturally occurring amino monosaccharide, has been used to treat or prevent osteoarthritis in humans. Recently, we have revealed that glucosamine inhibits platelet activation in vitro. However, the effect of in vivo administration of glucosamine has not yet been clarified. In this study, we administered glucosamine orally to guinea pigs and examined its effects on platelet functions.

METHODS

Glucosamine hydrochloride solution (0.5%, 5 mg/ml) was administered orally to guinea pigs ad libitum for 22 days, and platelet rich plasma was collected to evaluate platelet functions in vitro. Guinea pigs received an average of 400 mg glucosamine/animal/day.

RESULTS

Glucosamine-administration suppressed platelet aggregation in response to ADP by 51% (p < 0.01), but not platelet aggregation induced by collagen. Furthermore, glucosamine-administration inhibited the ADP-induced extracellular release of ATP and production of thromboxane A(2) by 91% and 96%, respectively (p < 0.001). In contrast, glucosamine did not affect the body-weights, platelet counts and bleeding time in guinea pigs after the administration.

CONCLUSIONS

These observations suggest that glucosamine is likely to exert an inhibitory action on platelets in vivo by suppressing platelet aggregation, ATP release, and thromboxane A(2) production. Thus, glucosamine could be expected as a novel and safe anti-platelet agent.