Fig. 1
From: RANKL system in vascular and valve calcification with aging
Scheme of vascular calcification through the RANK/RANKL/OPG axis. In vascular cells, RANK is expressed in both ECs and smooth muscle cells (VSMCs), and RANKL is primarily expressed in VSMCs. RANKL directly stimulates osteogenic differentiation of VSMCs via a decrease in MGP and indirectly promotes osteogenesis via BMP2, which is part of the TGF-β superfamily, from ECs. Promoting osteogenic differentiation by RANKL in VSMCs leads to synthesis of bone proteins and matrix calcification within the arterial vessel