Vitamin K2 Supplementation to Activate Matrix Gla Protein (MGP) as Endogenous Inhibitor of Vascular Calcification in Hemodialysis Patients

Vascular calcification (VC) is a predictor of cardiovascular morbidity and mortality. Hemodialysis (HD) patients suffer from severe vascular calcifications. Matrix Gla protein (MGP) is a central calcification inhibitor of the arterial wall and its activity depends on vitamin K-dependent γ-glutamate carboxylation. Noncarboxylated MGP, formed as a result of vitamin K deficiency, is associated with cardiovascular disease. Recent studies pointed towards poor vitamin K status in HD patients. We therefore aim to investigate whether daily vitamin K2 (MK-7) supplementation improves the bioactivity of vitamin K-dependent proteins in HD patients as assessed by circulating dephospho-noncarboxylated MGP (dp-ucMGP), noncarboxylated osteocalcin (ucOC) and noncarboxylated prothrombin (ucFII; PIVKA-II).