Premium
In vivo visualization of cortical porosity development in an animal model of progressive chronic kidney disease
Author(s) -
Buening Dorothy T,
Allen Matthew,
McNerny Erin
Publication year - 2017
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.31.1_supplement.lb25
Subject(s) - porosity , kidney disease , tibia , medicine , cortical bone , x ray microtomography , anatomy , biology , materials science , radiology , composite material
The effects of chronic kidney disease (CKD) on bone composition and structure is of interest due to the increased skeletal fracture risk observed in patients with CKD. The Cy/+ rat model of progressive polycystic kidney disease closely mimics the cortical bone loss and porosity observed in CKD patients. Our previous studies have shown increased and highly variable cortical porosity at 35 weeks of age in male Cy/+ rats, but the timing of the porosity's onset and its rate of progression were unknown. This study tested the feasibility of tracking the progression of CKD‐related bone porosity using longitudinal in vivo micro‐computed tomography (microCT) scans. MicroCT images of the distal tibia of normal and Cy/+ male rats were collected at 25, 30, and 35 weeks of age in order to visualize and quantify the developing porosity (Bruker Skyscan 1176, 9 micron resolution). A 1 mm volume of interest located 4 mm distal to the tibia‐fibula junction was chosen for analysis. Scans from 25, 30, and 35 weeks were 3D registered using SkyScan DataViewer preceding computational analysis allowing for a means to see and quantify the exact same locations and patterns of the porosity at various time points of the study. There was no significant difference in porosity between normal and CKD at either 25 or 30 weeks of age. At 35 weeks, CKD animals had significantly higher (11‐fold) cortical porosity compared to normal animals. A severe increase in cortical bone porosity was observed in the CKD animal model (see Figure 1). Although cortical bone loss occurred throughout the duration of the study, the majority of this bone loss occurred between 30 and 35 weeks (see Table 1). This experiment successfully applied in vivo microCT to monitor progressive bone loss in a CKD rat model, and it revealed that the severe but variable porosity previously observed in the Cy/+ rat appears after 30 weeks of age. Support or Funding Information Funding for this research was provided by the NIH F32DK108554 grant for Dr. Erin McNerny's post‐doctoral fellow research. Support for this project was received from Dr. John Davis at Alma College and Dr. Matthew Allen at Indiana University School of Medicine who established this summer internship exchange. 1 Cortical porosity of the distal tibia.Time Phenotype Count Mean Porosity (%) Standard Deviation25 weeks CKD 10 0.42 0.29 Normal 8 0.40 0.26 30 weeks CKD 11 0.50 0.47 Normal 16 0.36 0.15 35 weeks CKD 13 2.51 3.24 Normal 18 0.23 0.08