Abstract 14817: Iron Restricted Pair Feeding Attenuates Hypertension and Renal Damage in a Rat Model of Chronic Kidney Disease
Introduction: Iron is associated with the pathogenesis of chronic kidney disease (CKD). We have previously shown that dietary iron restriction prevented the development of renal damage in a rat model of CKD. Meanwhile, iron deficiency is associated with appetite loss. In addition, it is reported that calorie restriction prevented the development of end-stage renal pathology in a rat model of CKD. Thus, it is concerned that beneficial effects of iron restriction on renal damage may depend on calorie restriction. Here, we investigate the effects of pair-feeding iron restriction on renal damage in a rat model of CKD.
Methods: First, to determine the food intake, Sprague-Dawley (SD) rats were randomly given an ad libitum normal diet or an iron-restricted diet for 16 weeks, and the food intake were measured every 1 week. Second, CKD was induced by 5/6 nephrectomy in SD rats, and CKD rats were given either pair-feeding normal or iron-restricted diet for 16 weeks.
Results: The food intake was fewer in the iron-restricted diet group compared with the normal diet group for 16 weeks in SD rats (mean food intake: 20g/day vs 25g/day in the iron-restricted diet group vs the normal diet group, p<0.05). Based on the first experiments, we gave CKD rats either pair-feeding normal or iron-restricted diet (20g/day) for 16 weeks. Importantly, pair-feeding iron-restricted diet prevented the development of proteinuria, glomerulosclerosis, tubulointerstitinal damage, and podocyte injury in CKD rats. Of interest, pair-feeding iron-restricted diet led to increased urinary sodium/potassium exertion ratios and attenuated renal expression of nuclear mineralocorticoid receptor (MR) and SGK1, a key downstream effector of MR signaling. Moreover, CKD rats developed hypertension, whereas pair-feeding iron-restriction suppressed the development of hypertension.
Conclusions: Iron restricted pair feeding attenuates the development of hypertension and renal damage in CKD rats. These results indicate that beneficial effects of iron restriction on renal damage in CKD rats are dependent of iron restriction itself.
Author Disclosures: Y. Naito: None. H. Sawada: None. M. Oboshi: None. A. Fujii: None. M. Hosokawa: None. T. Iwasaku: None. Y. Okuhara: None. D. Morisawa: None. A. Eguchi: None. S. Hirotani: None. T. Mano: None. T. Tsujino: None. T. Masuyama: None.
- © 2014 by American Heart Association, Inc.