Coagulation meets calcification: the vitamin K system.
Morbidity and mortality are massively increased in patients with chronic kidney disease (CKD) and patients with end-stage renale disease (ESRD). Bone disease (renal osteodystrophy) and vascular disease (accelerated arteriosclerosis) are two typical entities contributing to this excess morbidity and mortality. Vitamin K and vitamin K-dependent-proteins play pivotal roles in the physiology of mineralization and in preventing ectopic calcification: two of these vitamin K-dependent-proteins are osteocalcin (regulating bone mineralization) and matrix-Gla protein (MGP, local calcification inhibitor in the vessel wall). Vitamin K deficiency impairs the physiological function of osteocalcin and MGP and, therefore, presumably contributes to bone demineralisation and vascular calcification (the so-called calcification paradox). In this context, the usage of vitamin K antagonists for long-term oral anticoagulation therapy might be risky especially in CKD patients exhibiting a high background level of vascular calcification. We present a summary of data describing the potential role of vitamin K deficiency and supplementation in bone and vascular disease in patients with CKD or ESRD.
Department of Nephrology and Clinical Immunology, University Hospital of the RWTH Aachen, Aachen - Germany.
Thilo
T
Krueger
Ralf
R
Westenfeld
Leon
L
Schurgers
Vincent
V
Brandenburg
D001779:Blood Coagulation Factors / Q000502:physiology; D002114:Calcinosis / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D002135:Calcium-Binding Proteins / Q000502:physiology; D002318:Cardiovascular Diseases / Q000209:etiology* / Q000378:metabolism / Q000517:prevention & control; D016326:Extracellular Matrix Proteins / Q000502:physiology; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications* / Q000378:metabolism / Q000473:pathology; D014812:Vitamin K / Q000502:physiology*; D000097568:Matrix Gla Protein
D001779:Blood Coagulation Factors; D002135:Calcium-Binding Proteins; D016326:Extracellular Matrix Proteins; D014812:Vitamin K; D000097568:Matrix Gla Protein