Abstract: TH-PO427

Restriction of Both P and Caloric Intake Decrease Renal Damage Induced by Cafeteria-Style Diet

Session Information

Category: Nutrition, Inflammation, and Metabolism

  • 1401 Nutrition, Inflammation, Metabolism

Authors

  • Lopez, Ignacio, University of Cordoba, Cordoba, Spain
  • Esquinas, Paula, Universidad Nacional de Colombia, Bogota, Colombia
  • Rios-Varo, Rafael, University of Cordoba, Cordoba, Spain
  • Pineda, Carmen, University of Cordoba, Cordoba, Spain
  • Raya bermudez, Ana isabel, University of Cordoba, Cordoba, Spain
  • Rodriguez, Mariano, Hospital Universitario Reina Sofia, Cordoba, Spain
  • Aguilera-tejero, Escolastico, University of Cordoba, Cordoba, Spain
Background


Energy dense diets, which also tend to be rich in P (cafeteria-style diets), are associated to metabolic syndrome, diabetes and kidney disease. In this study, renal damage after feeding a diet rich in P and calories was investigated. In addition, the influence of P and caloric intake restriction on renal pathology was assessed.

Methods

Wistar rats (n=32) were divided in 4 groups (n=8) and fed either: normocaloric (3518 kcal/kg) with normal P (0.6%) diet (NC-NP), hypercaloric (5241 kcal/kg) with high P (1.2%) diet (HC-HP), HC with low P (0.2%) diet (HC-LP), and hypocaloric (1314 kcal/kg) with HP diet (hC-HP). After 210 days, renal tissue was obtained and processed for optical (OM) and electronic microscopy (TEM). Lesions were graduated with a semi-quantitative scale of 0-3: 0 (absent), 1 (mild), 2 (moderate) and 3 (severe) or in percentage.

Results

The table 1 shows OM scores. Feeding HC-HP diet resulted in significant renal lesions. Both P and caloric restriction attenuated renal damage. P restriction was more effective at preventing nephrocalcinosis while caloric restriction was more effective at preventing glomerular damage.

Ultrastructurally, TEM lesions correlated to OM lesions. The main alterations observed in the HC-HP group by TEM were: hyperactivity of the epithelial and mesangial cells, capillary remodeling, tubular atrophic changes and increased fibroblast and cell inflammatory activity. These lesions were attenuated in the HC-LP and hC-HP groups.


Conclusion

In conclusion, the results suggest a synergistic deleterious effect of high caloric and high phosphorus intake on the kidney. Both P and caloric restriction can attenuate renal damage although their influence on renal pathology show differential characteristics.

Table1
 Glomerular
Retraction (%)
Basal Membrane
Thickness (0-3)
Tubular
Dilatation (0-3)
Tubular
Atrophy (0-3)
Fibrosis
(0-3)
Calcification
(0-3)
NC-NP10,00±3,77a0,00±0,00a0,75±0,46a0,12±0,33a0,00±0,00a0,00±0,00a
HC-HP38,5 ± 4,81b1,88 ± 0,35b2,25 ± 0,70b1,75 ±0,46b2,25 ± 0,70b2,25 ± 0,70b
HC-LP16.5±2,26c1,50±0,53c1,25± 0,46a0,75±0,70c0,75±0,46c0,00±0,00a
hC-HP12,50±3,29a1,12±0,35c1,12±0,83a0,96±0,35c1,12±0,64c0,625±0,51c

Values are mean ±SE; a,b,c For each parameter, data with different superscripts are significantly (P < 0.05) different between diets.

Funding

  • Government Support - Non-U.S.