OPG/RANK/RANKL signaling system and its significance in nephrology

Recent years brought the discovery of new members of TNF receptor superfamily - osteoprotegerin/receptor activator of nuclear factor-kappa B and its ligand (OPG/RANK/RANKL) system as regulator of bone remodeling. Further studies showed its involvement in control of vascular and immune system. Animal studies' results confirm the OPG/RANK/RANKL role in pathogenesis of vascular calcifications and osteoporosis. Human studies, especially in patients with chronic kidney disease (CKD), have brought many conflicting data. Understanding of exact contribution of each molecule creating this axis may be crucial for diagnosis and treatment of CKD complications involving renal osteodystrophy and vascular calcification. In this review we try to summarize recent knowledge and OPG/RANK/RANKL role in patient with chronic kidney diseases.