Abstract: FR-PO1187
Plasma Calciprotein Particles and Calcification Propensity in Cats with CKD Stabilized on a Phosphate-Restricted Diet
Session Information
- CKD: Mechanisms - 2
October 25, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: CKD (Non-Dialysis)
- 2303 CKD (Non-Dialysis): Mechanisms
Authors
- Tang, Pak Kan, The Royal Veterinary College Department of Comparative Biomedical Sciences, London, London, United Kingdom
- Kuro-o, Makoto, Jichi Medical University Center for Molecular Medicine, Shimotsuke, Tochigi, Japan
- Tsuchida, Miki, Jichi Medical University Center for Molecular Medicine, Shimotsuke, Tochigi, Japan
- Geddes, Rebecca, The Royal Veterinary College Department of Clinical Science and Services, Hatfield, Hertfordshire, United Kingdom
- Jepson, Rosanne E., The Royal Veterinary College Department of Clinical Science and Services, Hatfield, Hertfordshire, United Kingdom
- Chang, Yu-Mei, The Royal Veterinary College Department of Comparative Biomedical Sciences, London, London, United Kingdom
- Elliott, Jonathan, The Royal Veterinary College Department of Comparative Biomedical Sciences, London, London, United Kingdom
Background
Fetuin-A aggregates with calcium and phosphate ions to form calciprotein monomers, preventing precipitation (low-density calciprotein particles [L-CPP]). Consolidation of L-CPP with further protein leads to amorphous CPP which transform spontaneously into pro-inflammatory crystalline CPP over time (high-density CPP [H-CPP]). The transition time (T50) from amorphous to crystalline CPP indicates the calcification propensity. This study evaluated relationships between CPP levels, T50 and CKD-MBD parameters in cats with azotemic CKD.
Methods
Cross-sectional study: Frozen heparinized fasted plasma samples from cats with naturally occurring CKD stabilized on a phosphate-restricted diet (forming ≥50% of diet consumed) were retrospectively identified for CPP and calcification propensity (T50) assessment. Total CPP (T-CPP), L-CPP and H-CPP were measured by an infrared fluorescent bisphosphonate (OsteoSense), in conjunction with gel filtration. Associations between CPP, T50 and CKD-MBD parameters were evaluated by Spearman or Pearson correlations and linear regression models.
Results
38 euthyroid client-owned cats with International Renal Interest Society (IRIS) stage 2–3 azotemic CKD were enrolled. Moderate negative correlations were found between T-CPP, L-CPP and H-CPP with T50 (Table 1). FGF-23 correlated positively with T-CPP, L-CPP (Table 1) and total calcium (r=0.41; P=0.011), and negatively with T50 (r=-0.44; P=0.006) and total magnesium (r=-0.42; P=0.011). FGF-23 was a significant predictor of T-CPP and L-CPP.
Conclusion
Plasma FGF-23 was a major determinant of T-CPP and L-CPP in fasted samples obtained from CKD cats stabilized on restricted phosphate diets. Comparable findings were reported in human patients with CKD, suggesting a similar relationship between FGF-23 and CPP in both species. Like humans, cats spontaneously develop CKD and FGF-23 is predictive of progression, therefore, studying cats could provide additional insights into the pathophysiology underlying CPP and CKD progression for humans.
Funding
- Commercial Support – Royal Canin SAS