MGP and chronic kidney disease: An imbalance between factors that promote calcification (e.g., bone morphogenetic protein (BMP)-2, 4, and 6; osteocalcin; bone sialoprotein; alkaline phosphatase; calcium; phosphate) and those that inhibit it (e.g., carboxylated MGP, osteopontin, osteoprotegerin, fetuin A, pyrophosphate, klotho, vitamin K and magnesium) in CKD could lead to the development of vascular calcification [26,27].