Role of Vitamin k 2 on Matrix Gla Protein and Vascular Stiffness in Hemodialysis Patients

Abstract

Background: Matrix Gla protein (MGP) acts as a potent local inhibitor of vascular
calcification. However, to be active, MGP must be phosphorylated and carboxylated; such
carboxylation is vitamin K-dependent, and phosphorylation is necessary for the secretion of
MGP. This study aimed to investigated the effect of vitamin K2 on MGP levels after 3
months’ supplementation and the relationship between MGP level and vascular stiffness in
hemodialysis patients. Patients and methods: This interventional, double armed, clinical trial
(Single-blinded) study was conducted in the dialysis Unit in Al-Ahrar Teaching Hospital,
Sharkia on 48 end-stage renal disease (ESRD) patients on regular hemodialysis divided into 2
groups; 24 patients receiving Mk -7 as 90 mcg/day and 24 patients receiving placebo. Carotid
duplex ultrasound for right and left common carotid arteries was done to assess Peak Wave
Velocity (PWV) and the presence or absence of atheromatous plaques, prior to administering
MK-7 and again after 3 months, for both groups. Results: There was statistically nonsignificant difference between the studied groups regarding hemoglobin, serum calcium,
phosphorus, potassium, sodium, alkaline phosphatase, Ktv and parathyroid hormone. There
was statistically non-significant difference between the studied groups regarding baseline
matrix Gla protein. There was statistically significant difference between the studied groups
regarding matrix Gla protein after 3 months of administration of vitamin k2 supplementation
and placebo within intervention and placebo groups respectively. Conclusions: Vitamin k2
supplementation to hemodialysis patients will reduce ucMGP, which in turn reduces
calcification and stiffness of blood vessels and cardiovascular system which in turn reduces
cardiovascular morbidity and mortality.