The Effect of Calcium Deficiency on Bone Properties in Growing Rats

Background: In this work, the study of the physicochemical properties of the rat bones that were fed under severe and moderate calcium depletion was carried out. Calcium depletion is a common problem in the diet of the third world. Objective: Three calcium levels: 5000, 2500, and 1039 mg/kg, were used in the diets to evaluate the influence of calcium deficiency on the bone quality by post-mortem tests. Methods: Inductive Coupled Plasma was used to study the elemental chemical composition of the bones; X-ray diffraction evaluated the bone structure and crystallinity; the microstructure and architecture were investigated using scanning electron microscopy; thermogravimetric analysis assessed the ratio between organic and inorganic phases of bones. All of these results were correlated with flexion and compression test determining the biomechanical properties to evaluate the bone quality. Results: The results showed that severe calcium depletion (75% depletion, 1039 mg/kg) was a critical factor in the unsuitable mineralization process responsible for the deterioration of bone quality. Bone architecture with delicate trabeculae caused the poor mechanical response. For moderate calcium depletion (50% of the request, 2500 mg/kg), the bone quality and its mechanical behavior showed less deterioration in comparison with bones of severe calcium depletion diet. Conclusion: By using this animal model, the effect of calcium depletion in bone mineralization in rats was understood and can be extrapolated for humans.