High cardiovascular mortality in patients with end-stage renal disease is closely associated with arterial medial calcification (AMC) caused by hyperphosphatemia, the mechanism of which associated hormones (FGF-23, klotho) and osteochondrogenic events is unclear. We examined the effect of Lanthanum carbonate on AMC via regulating the abnormalities in phosphorus metabolism of uremic rats.Main methods:
45 healthy SD rats were randomly divided into 3 groups: Normal group (n = 15), CRF group (n = 15), CRF diet supplemented with 2% La (n = 15). AMC in great arteries were evaluated by VonKossa. Osteochondrogenic specific genes were analyzed by Immunohistochemistry and qRT-PCR. Serum FGF-23 and klotho levels were detected by ELISA kit.Key findings:
Serum phosphate was markedly increased in CRF group (6.94 ± 0.97 mmol/L) and 2%La group (5.12 ± 0.84 mmol/L) at week 4, while the latter became hypophosphatemic (2.92 ± 0.73 mmol/L vs CRF group, p < 0.01) at week 10. Inhibitory effect of 2%La on development of AMC was reflected by downregulated Runx2, Osterix, BSP, Osteocalcin and collagenII and a reduction of FGF-23 at week 4(vs CRF group, p < 0.01) but not week 10.Significance:
Beneficial effects of Lanthanum carbonate on progression of AMC in CRF could be mainly due to the decreased phosphate retention and FGF-23 in early stage and likewise a reduction of bone-associated proteins via osteochondrogenic pathway. Lanthanum carbonate has no effect on soluble klotho and serum FGF-23 in late stage of CRF.