Ginger (Zingiber officinale Roscoe)-derived natural compounds inhibit vitamin K-dependent carboxylation: a novel possibility for traditional Chinese medicine-induced bleeding risk.

BACKGROUND: While bleeding associated with anticoagulants is often predictable and manageable, non-anticoagulant induced bleeding poses greater clinical challenges due to unclear mechanisms. These disorders primarily arise from coagulation factor dysfunction, with emerging evidence implicating off-target disruption of the vitamin K cycle. However, existing research on Traditional Chinese Medicines (TCMs) has largely focused on their antiplatelet effects and direct inhibition of coagulation proteases. Given the complex, multi-component nature of TCMs, a comprehensive evaluation of their potential to interfere with vitamin K cycle remains critically needed.

PURPOSE: This study aims to systematically investigate TCM-derived compounds that interfere with the vitamin K cycle, thereby elucidating novel mechanisms underlying TCM-induced coagulopathy and informing their safety assessment.

STUDY DESIGN: A high-throughput vitamin K-dependent (VKD) carboxylation assay was employed to screen 1931 pharmacologically characterized bioactive compounds derived from TCMs. Lead candidates were further validated through in vivo mouse experiments.

METHODS: The VKD carboxylation assay quantified compound-induced inhibition of γ-carboxylation. Positive hits were evaluated for dose-dependent effects, and mechanism of potential inhibitors were investigated using vitamin K recue assay and molecular docking analysis. Their anticoagulant activity was validated in vivo in mice following oral administration.

RESULTS: Screening identified two ginger (Zingiber officinale Roscoe)-derived compounds-6-paradol and 10-gingerol-as first-in-class natural vitamin K antagonists that inhibited γ-carboxylation in a dose-dependent manner. Vitamin K rescue assays and molecular docking analyses demonstrated that both compounds directly target vitamin K epoxide reductase (VKOR), thereby disrupting the vitamin K cycle. Oral administration in mice significantly prolonged prothrombin and tail bleeding times, confirming their anticoagulant effects.

CONCLUSION: Our study establishes 6-paradol and 10-gingerol, derived from ginger, as the first natural inhibitors of VKOR. This finding provides a novel mechanistic basis for understanding bleeding risks associated with TCMs, thereby highlighting the "double-edged sword" nature of their bioactive components. Consequently, this study underscores the critical need to balance the exploration of TCM's therapeutic potential with rigorous safety assessments, including the specific evaluation of VKOR inhibition.