Nutrition-Related Peptides and Bone Homeostasis

Abstract

THE SKELETON SERVES two main functions. First, it has a structural role, to support, protect, and facilitate the function of the soft tissues. Second, it is a mineral reservoir, which can be drawn on when dietary intake is inadequate to meet the body’s needs. Optimal function in each of these roles requires regulation of skeletal mass and function in relation to the demands being placed on it. From the structural perspective, the size and strength of the skeleton should be proportional to the mass of soft tissue that it supports, so that the skeleton is structurally adequate without being larger or heavier than necessary. To function as an effective mineral reservoir, there must be a mechanism by which mineral release from the skeleton can occur during times of privation and its replacement be affected when there is dietary abundance. Both the structural and reservoir roles of the skeleton suggest that skeletal homeostasis should be regulated by factors that reflect soft tissue mass on the one hand and nutritional status on the other. Because soft tissue mass and nutrition are themselves linked, there is the possibility of a complex interaction of regulatory factors that act across these two dimensions. Recent research indicates that this is the case, and this Perspective will review our current understanding of this relatively new area of bone science.