Effect of Ginkgo biloba extract on anticoagulation of 4 new oral anticoagulants

To explore the effect of Ginkgo biloba extract (GBE) on anticoagulation of 4 new oral anticoagulants (NOACs), dabigatran, apixaban, rivaroxaban and edoxaban in vitro, thrombin time (TT), prothrombin time (PT), activated partial thrombin time (APTT) and the activity of coagulation factor Xa (FXa) of rat plasma were measured at different concentrations of NOACs, GBE or NOACs combined with GBE, respectively. The results showed that TT, PT and APTT were prolonged with the increase of NOACs concentration in the range of 0-500 ng/mL; that except for TT of rivaroxaban, other results showed a good linear correlation with NOACs concentration (r²= 0.78-0.98); and that FXa activity decreased with increased concentration of FXa inhibitors (apixaban, rivaroxaban and edoxaban), with a good linear correlation with concentration of FXa inhibitors in the range of 0-250 ng/mL (r²= 0.85-0.94). GBE had no significant effect on TT, PT and APTT (P>0.05) in the concentration range of 0-500 μg/mL, but FXa activity had a positive linear correlation with GBE concentration (r²= 0.840 4). TT was prolonged with increasing GBE concentration when dabigatran was combined with GBE. When the above FXa inhibitors were combined with GBE, TT shortened and FXa activity increased with rising GBE concentration. There were no significant changes in PT and APTT (P>0.05) when NOACs were combined with GBE. The study results suggest that GBE may synergize with the anticoagulant activity of dabigatran and antagonize the anticoagulant activity of FXa inhibitors, possibly due to its role in increasing FXa activity.