Subacute administration of Astaxanthin inhibits vitamin K-dependent clotting factors in rats.

This study investigated the effect of Astaxanthin (ASTX) on levels and activities of the clotting factors in control rats. Untreated or ASTX-treated rats (10 mg/kg, dissolved in DMSO) were used in this study. ASTX treatment was conducted for 10 days daily. ASTX significantly decreased the platelet count and prolonged values of prothrombin and activated partial thromboplastin time (PT and aPTT, respectively). Besides, it significantly reduced serum levels of vitamin K and the plasma activities and hepatic expression of vitamin K-dependent factors (FII, FVII, FIX, and FX) without altering the activities or levels of all other clotting factors nor plasma levels of fibrinogen or von Willebrand Factor. These effects were associated with a reduction in serum and fecal levels of cholesterol and triglycerides and lower serum levels of LDL-c. In conclusion, ASTX exerts an in vivo hypocoagulant effects mediated by the inhibition of vitamin K-dependent factors. PRACTICAL APPLICATIONS: The findings presented here are the first that show the ability of Astaxanthin (ASTX) to inhibit coagulation in rats by suppressing the circulatory levels of Vitamin K and decrease the synthesis and release of all Vitamin-K dependent factor (FII, FVII, FIX, and FX). Since some synthetic anti-coagulants had side effects, these findings may illustrate ASTX as a natural anti-coagulant with fewer side effects that require further investigation in more clinical trials. Besides, awareness should be established for those individuals with some bleeding disorders who are being treated with ASTX for other beneficial effects.