BoneKEy Reports | BoneKEy Watch
Exploring interactions between dietary calcium, genetics and bone remodeling
DOI:10.1038/bonekey.2014.2
The interactions between diet, calcium metabolism and genetics are not well understood. Replogle et al. provided 11 different inbred mouse strains, all genetically diverse, fed on either an adequate calcium diet (0.5%) or a low calcium diet (0.25%).
The mouse strains showed significant variation in terms of their efficiency of intestinal Ca absorption and their ability to adapt Ca absorption and bone parameters in response to a low Ca diet. Ca absorption efficiency was shown to correlate directly with bone mineral density, an effect, the authors propose, that was due to a beneficial impact on trabecular bone.
Two of the inbred mouse lines fed the low Ca diet showed a proportional increase in Ca absorption from the intestine, with a resultant increase in serum Ca levels. Other lines were classed as hyper-responders because the increase in intestinal Ca absorption was high in relation to the rise in serum Ca levels. Two lines showed greater Ca absorption from the intestine but no change in serum concentration.
Editor’s comment: Among several intestinal proteins proposed to mediate Ca absorption, the mRNA levels of transient receptor potential vanilloid member 6 (TRPV6), calbindin D9k (CaBPD9k) and plasma membrane Ca ATPase 1b (PMCA1b) were indeed related to dietary Ca. However, a significant amount of the variation in Ca absorption is not explained by the proposed model.
This work is licensed under a
Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States License.