Updated mechanisms of calcification of cardiovascular system and its correction in chronic kidney disease

Abstract

In chronic kidney disease (CKD), progressive decline in kidney function leads to disorders of mineral metabolism, which are usually called secondary hyperparathyroidism. An increase in the serum concentration of the parathyroid hormone is associ­ated with a decrease in the level of calcium and calcitriol and/or an increase in the level of fibroblast growth factor-23 and inorganic phosphate in serum. CKD-related disorders of mineral and bone metabolism are associated with other metabolic disorders, such as acidosis, protein-energy wasting, inflammation, and accumulation of uremic toxins. This contributes to vascular calcification, which is a consequence of an imbalance between numerous inhibitors and promoters of soft tissue min­eralization. Vascular calcification is a degenerative process characterized by the accumulation of calcium and phosphate salts in the artery wall. This is observed in almost all vascular areas and can develop in the media, intima, or both vascular layers of the arteries. Calcification of the intima usually occurs due to atherosclerosis and may be responsible for coronary ischemic events. Conversely, media calcification is non-exclusive and predominantly develops along elastic fibers. As a result, media calcification increases vascular stiffness, aortic pulse wave velocity, systolic and pulse blood pressure, contributing to the de­velopment of left ventricular hypertrophy and heart failure. This review examines the current understanding of the mechanisms that lead to the development of vascular calcification in CKD. The participation of factors such as inflammation, age glycation end products, indoxyl sulfate, and others in calcification processes is discussed. Promising therapeutic goals associated with a new understanding of the mechanisms of cardiovascular calcification in CKD are identified.