Kidney Week

Abstract: SA-PO239

Impact of Phosphate Binders on Bone Histomorphometry in Rats Submitted to Diets with Different Concentrations of Phosphorus

Session Information

• CKD-MBD: Basic and Translational
  October 26, 2024 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Bone and Mineral Metabolism

• 501 Bone and Mineral Metabolism: Basic

Authors

• Truyts, Tânia Priante de Oliveira Madid, Laboratório de Fisiopatologia Renal, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil

Tânia Priante de Oliveira Madid Truyts

• Ferreira, Juliana Cunha, Laboratório de Fisiopatologia Renal, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil

Juliana Cunha Ferreira, MD

• Neves, Katia R., Laboratório de Fisiopatologia Renal, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil

Katia R. Neves, MD, PhD

• Dominguez, Wagner, Laboratório de Fisiopatologia Renal, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil

Wagner Dominguez, MBChB

• Elias, Rosilene M., Laboratório de Fisiopatologia Renal, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil

Rosilene M. Elias, MD, PhD

• Jorgetti, Vanda, Laboratório de Fisiopatologia Renal, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil

Vanda Jorgetti, MD, PhD

• Moyses, Rosa M.A., Laboratório de Fisiopatologia Renal, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil

Rosa M.A. Moyses, MD, PhD

• dos Reis, Luciene, Laboratório de Fisiopatologia Renal, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, São Paulo, São Paulo, Brazil

Luciene dos Reis, PhD

Background

Managing hyperphosphatemia is important in treating chronic kidney disease (CKD) to prevent bone and cardiovascular complications. Phosphate (P) binders play a fundamental role in this control. This study evaluated the impact of calcium carbonate (CaCO3) and sevelamer carbonate (Sev) on bone tissue in nephrectomized (Nx) and parathyroidectomized (PTx) rats fed normal and high-phosphorus diets.

Methods

Wistar rats underwent 5/6 nephrectomy (Nx) and parathyroidectomy (PTx) and were fed diets with different P concentrations (0.6% and 1.2%). The animals were divided according to diet and treatment with the binders. Biochemical analyses and bone histomorphometry were performed on all animals. Statistical analysis using ANOVA General Linear Model was applied to study the effects of diet and treatment on bone tissue.

Results

Table 1 describes the interaction between different P concentrations in the diet and the effects of both treatments on biochemical analysis and bone histomorphometry. Post-test analysis showed that P excretion fraction and ionized calcium (Cai) were influenced by both different diets and CaCO3 and sevelamer. Also showed that formation parameters were influenced by P and treatment, significantly high in the rats treated with CaCO3. Resorption parameters were influenced by treatment but not by P, although no interaction was observed.

Conclusion

Our results demonstrated that, although CaCO3 was effective in reducing serum P, it significantly altered bone formation and resorption parameters, possibly due to calcium overload. In contrast, the use of sevelamer did not alter bone parameters. These findings reinforce the importance of considering the side effects related to calcium load when choosing phosphate binders. The study suggests that sevelamer may be a safer alternative to preserve bone health and control hyperphosphatemia in these experimental model.

Table 1.