PHYLLOQUINONE TRANSPORT AND ITS INFLUENCE ON GAMMA-CARBOXYGLUTAMATE RESIDUES OF OSTEOCALCIN IN PATIENTS ON MAINTENANCE HEMODIALYSIS

Plasma concentrations of phylloquinone in 42 fasting hemodialysis pati ents showed a much wider range than in healthy adults. Phylloquinone c oncentrations were best predicted by the concentration ratio of beta-v ery-low-density-lipoprotein to low-density-lipoprotein cholesterol (r = 0.71), which is closely related to chylomicron-remnant clearance. Ph ylloquinone concentrations in plasma were related to apolipoprotein E genotype in the order E2 > E3 > E4. The percentage of carboxylated ost eocalcin (HBC) was related to the plasma concentration of phylloquinon e in patients with the apolipoprotein E genotype E3/3 (r = 0.52, P < 0 .05), and in patients with the genotypes E2/3 and E2/2 (r = 0.23, P < 0.1). Overall, plasma triglyceride concentration was a better predicto r for HBC than was the plasma concentration of phylloquinone. These re sults point to the overriding importance of chylomicrons for the trans port of phylloquinone to liver and bone. Delivery to osteocalcin-produ cing osteoblasts seemed impaired in patients with the low receptor-aff inity apolipoprotein variant E2, suggesting a major role of receptor-m ediated chylomicron-remnant uptake in the transport of phylloquinone t o bone.