Kidney Week

Abstract: PO0527

Assessment of Vascular Calcification Using Micro-CT Quantification in a Vitamin D Rat Model

Session Information

• Bone and Mineral Metabolism: Causes and Consequences
  November 04, 2021 | Location: On-Demand, Virtual Only
  Abstract Time: 10:00 AM - 12:00 PM

Category: Bone and Mineral Metabolism

• 401 Bone and Mineral Metabolism: Basic

Authors

• Bassissi, Firas, Sanifit Therapeutics, Palma, Balearic Islands, Spain

Firas Bassissi, PhD

• Sabador, David, Centro Nacional de Investigaciones Oncologicas, Madrid, Madrid, Spain

David Sabador,

• Blasco Ferrer, Marc, Sanifit Therapeutics, Palma, Balearic Islands, Spain

Marc Blasco Ferrer,

• Garaulet Perez, Guillermo, Centro Nacional de Investigaciones Oncologicas, Madrid, Madrid, Spain

Guillermo Garaulet Perez,

• Perez, Maria del mar, Sanifit Therapeutics, Palma, Balearic Islands, Spain

Maria del mar Perez,

• Ferrer, Miquel D., Sanifit Therapeutics, Palma, Balearic Islands, Spain

Miquel D. Ferrer,

• Mulero, Francisca, Centro Nacional de Investigaciones Oncologicas, Madrid, Madrid, Spain

Francisca Mulero,

• Salcedo, Carolina, Sanifit Therapeutics, Palma, Balearic Islands, Spain

Carolina Salcedo,

Background

Micro-computed tomography (micro-CT) scanning could be an alternative technique of both visualization and quantification of calcium content in vessels. Our aim was to standardize the micro-CT calcium quantification methodology and evaluate its reliability in a rat model of calcification.

Methods

Six Sprague-Dawley rats were induced by three consecutively daily subcutaneous administrations of 150 klU/kg vitamin D3 and sacrificed 5 days after induction. Three of the rats were subcutaneously treated with 60 mg/kg SNF472 (G1), an inhibitor of calcification, and the rest were treated with saline (G2). One additional rat was not induced nor treated and served as negative control. Micro-CT was performed in aorta and femoral arteries with an isotropic resolution of 45 µm, 400 projections collected in one full rotation of the gantry in 10 min, x-ray tube at 80 kV and 150 µA. A phantom made of a laser cut aluminum skeleton was scanned with the same protocol to simulate bone. After the image analysis, the vessel samples were digested (1:1 HNO₃:HClO₄) and total calcium was quantified using an inductively coupled plasma atomic emission spectrometry (ICP-AES).

Results

The threshold for calcium detection was established at 153.8 Hounsfield Units (HU). Rats treated with vitamin D presented more calcium deposits than the control and SNF472 treated rats (7.6 ± 6.1 HU in G2 vs 3.3 ± 3.2 HU in G1). The volume of calcium deposits in femoral samples was similar between groups. The quantification of calcium by ICP-AES brought similar results in aorta (>50% inhibition with SNF472 treatment) but not in femoral samples, as in this tissue increased calcium content was quantified in vitamin D-treated rats when compared to the control rat. A significant correlation was obtained between the calcium deposits quantified by micro-CT and the total calcium quantified by ICP-AES.

Conclusion

The threshold-based quantification method by micro-CT can be a useful and reliable tool to evaluate vascular calcification and the efficacy of inhibitors of vascular calcification in rat models, especially in large-diameter vessels such as aorta.

Funding

• Commercial Support – Sanifit Therapeutics