Safety Study of Vitamin K2 During Anticoagulation in Human Volunteers

Safety Study of Vitamin K2 During Anticoagulation in Human Volunteers

Oral anticoagulants that are widely used for the treatment of thrombo-embolic disease exert their effect by blocking the recycling of vitamin K. Vitamin K acts as a co-factor in the posttranslational carboxylation of vitamin K-dependent proteins such as osteocalcin and matrix-gla protein. It is important to quantify the dose-response relationship of the interaction between vitamin K and oral anticoagulants and to investigate at what dosage vitamin K will interfere with oral anticoagulants in a clinically relevant way.

From all K-vitamins, menaquinone-7 has been identified as the most effective cofactor for the carboxylation reaction of Gla-proteins. In this respect it is important to quantify the dose-response relationship of the interaction between oral anticoagulants and menaquinone-7. The primary objective of the study is to demonstrate at what menaquinone-7 intake the vitamin will interfere with oral anticoagulants in a clinically relevant way. Clinically relevant is defined as a decrease in level of anticoagulation that would require a change in oral anticoagulant treatment in order to stay within target levels. Secondary objective of the study is to investigate changes in carboxylation level of osteocalcin and matrix-gla protein after menaquinone-7 supplementation during the oral anticoagulation treatment period. This will demonstrate whether during oral anticoagulation menaquinone-7 will be transported preferentially to the liver or to other target tissues.

Inclusion Criteria:

• Healthy male and female adults between 18 and 45 years of age.
• Subjects of normal body weight and height according to BMI < 30
• Subject has given written consent to take part in the study

Exclusion Criteria:

• Subjects with (a history of) of coagulation disorders
• Subjects with (a history of) metabolic or gastrointestinal disease
• Subjects using (multi)-vitamin supplements containing vitamin K
• Subjects presenting chronic inflammatory diseases
• Subjects using any medication 3 months prior to the study (e.g. corticoϊd treatment, oral anticoagulants)
• Subjects using oral anticonception
• Subject with (a history of) soy allergy