Phosphorus restriction does not prevent the increase in fibroblast growth factor 23 elicited by high fat diet
Pineda Martos, Carmen María
Muñoz-Castañeda, Juan R.
Aguilera Tejero, Escolástico
Raya, Ana I.
PublisherPublic Library of Science
METS:Mostrar el registro METS
PREMIS:Mostrar el registro PREMIS
MetadataShow full item record
This study was designed to evaluate the influence of phosphorus (P) restriction on the dele- terious effects of high fat diets on mineral metabolism. Twenty-four rats were allotted to 3 groups (n = 8 each) that were fed different diets for 7 months. Rats in group 1 were fed nor- mal fat-normal P (0.6%) diet (NF-NP), rats in group 2 were fed high fat- normal P diet (HF- NP) and rats in group 3 were fed high fat-low P (0.2%) diet (HF-LP). Blood, urine and tissues were collected at the end of the experiments. When compared with the control group (NF- NP), rats fed HF diets showed increases in body weight, and in plasma concentrations of tri- glycerides and leptin, and decreased plasma calcitriol concentrations. In rats fed HF-NP plasma fibroblast growth factor 23 (FGF23) was higher (279.6 ± 39.4 pg/ml vs 160.6 ± 25.0 pg/ml, p = 0.018) and renal klotho (ratio klotho/GAPDH) was lower (0.75 ± 0.06 vs 1.06 ± 0.08, p < 0.01) than in rats fed NF-NP. Phosphorus restriction did not normalize plasma FGF23 or renal klotho; in fact, rats fed HF-LP, that only ingested an average of 22.9 mg/day of P, had higher FGF23 (214.7 ± 32.4 pg/ml) concentratio ns than rats fed NF-NP (160.6 ± 25. 0 pg/ml), that ingested and average of 74.4 mg/day of P over a 7 month period. In conclusion, our results demonstrate that severe P restriction over a prolonged period of time (7 months) does not normalize the increase in circulating FGF23 induced by HF diets. These data indi- cate that the deleterious effects of high fat diet on the FGF23/klotho axis are not eliminated by reduced P intake.