Role of the Wnt/β-Catenin Pathway in Renal Osteodystrophy

Figure 1

Mineral and bone disorders in chronic kidney disease (CKD). Elevated phosphorus (P), low calcium (Ca), and 1,25 (OH)₂D (vitD) stimulate parathyroid hormone (PTH) production by the parathyroid glands, which leads to increased bone turnover and P excretion by the kidneys. High PTH and P also seem to either directly or indirectly stimulate fibroblast growth factor 23 (FGF23) production by osteoblasts and osteocytes, though this seems at least partly mediated by an upregulation of vitD by high PTH, which in turn activates FGF23 production. While FGF23 stimulates P excretion, it further suppresses vitD production. Suppression of PTH levels may arise from Ca and vitD supplements or treatment with calcimimetics in CKD. Suppressed PTH levels will lead to decreased bone turnover.