Antiplatelet activity of a Korean red ginseng–derived saponin fraction and its inhibition of influenza A virus–induced thrombosis

Abstract

Background

Platelets play a central role in thrombus formation, which is a major cause of morbidity and mortality worldwide. Viral infections have been reported to further promote thrombus formation, posing a critical risk in unpredictable pandemic situations. Therefore, we evaluated whether a Korean red ginseng–derived saponin fraction could serve as a safe and effective antithrombotic agent by assessing its inhibitory effects.

Methods

Human platelets were examined using an aggregometer, flow cytometry, fluorescence assays, ELISA kits, and western blotting to assess cGMP, intracellular Ca²⁺ levels, fibrinogen binding, granule secretion (ATP and serotonin), and phosphorylation of IP₃R, VASP, MAPKs, PI3K/Akt, and cPLA₂. Thrombin-induced clot retraction was quantified. The in vivo effects were further evaluated in influenza A virus (IAV)-infected mice using a FeCl₃-induced carotid artery thrombosis model, where thrombus formation and blood flow were monitored.

Results

The saponin fraction markedly inhibited platelet aggregation, enhanced cGMP production, and increased phosphorylation of IP₃R and VASP Ser²³⁹. Conversely, it suppressed phosphorylation of MAPKs (JNK and p38), PI3K/Akt, and cPLA₂, thereby blocking downstream signaling pathways. In vivo, IAV infection accelerated thrombus formation and reduced blood flow, whereas administration of the saponin fraction significantly attenuated these pathological changes.

Conclusion

The saponin fraction effectively suppressed platelet activation in vitro and thrombus formation in vivo, even under virus-induced prothrombotic conditions. These findings suggest that the saponin fraction has potential as a safe and effective natural antithrombotic agent.