Roxadustat improves renal osteodystrophy by dual regulation of bone remodeling

Purpose Renal osteodystrophy (ROD), a component of chronic kidney disease-mineral and bone disorder (CKD-MBD) can lead to bone loss increasing fracture risks in CKD patients. Therefore, it is important to prevent and treat ROD. Activation of hypoxia-inducible factor-1 alpha (HIF-1 alpha) signaling was reported to prevent osteoporotic bone loss. Roxadustat, which is used to treat renal anemia in the clinic, is a novel HIF stabilizer. In our study, we aimed to investigate the effects of roxadustat on ROD. Methods We established an adenine-induced CKD rat model. Roxadustat was administered intragastrically to normal and CKD rats for 4 weeks. Hemoglobin concentrations and serum biochemical parameters were tested, and bone histomorphometric analysis was performed. Results CKD rats exhibited impaired renal function with anemia, secondary hyperparathyroidism and high-turnover ROD-induced significant bone loss. Roxadustat ameliorated renal anemia and attenuated the extreme increase in intact parathyroid hormone (iPTH) and fibroblast growth factor 23 (FGF23) in CKD rats. Bone histomorphometric analysis showed that roxadustat significantly alleviated bone loss and bone microarchitecture deterioration in CKD rats by increasing osteoblast activity and inhibiting osteoclast activity. We did not find that roxadustat had significant effects on bone metabolism in normal rats. Conclusion Roxadustat can improve ROD via dual regulation of bone remodeling. The use of roxadustat may be a promising strategy to treat osteoporotic bone disorders, such as ROD.