The XXXX of bone.

@entity172 @entity174 @entity28 @entity170 @entity342 @entity1096 @entity413
UNASSIGNED: During the last decades, @entity28 and @entity170 have become important global health problems, and the belief that @entity28 is protective against @entity170 has recently come into question. In fact, some recent epidemiologic and clinical studies have shown that a high level of fat mass might be a risk factor for @entity170 and @entity174 . Several potential mechanisms have been proposed to explain the complex relationship between adipose tissue and bone. Indeed, adipose tissue secretes various molecules, named adipokines, which are thought to have effects on metabolic, skeletal and cardiovascular systems. Moreover, fat tissue is one of the major sources of aromatase, an enzyme that synthesizes @entity172 from @entity342 precursors, hormones that play a pivotal role in the maintenance of skeletal homeostasis, protecting against @entity170 . Moreover, bone cells express several specific hormone receptors and recent observations have shown that bone-derived factors, such as osteocalcin and @entity1096 , affect body weight control and @entity413 homeostasis. Thus, the skeleton is considered an endocrine target organ and an endocrine organ itself, likely influencing other organs as well. Finally, adipocytes and osteoblasts originate from a common progenitor, a pluripotential mesenchymal stem cell, which has an equal propensity for differentiation into adipocytes or osteoblasts (or other lines) under the influence of several cell-derived transcription factors. This review will highlight recent insights into the relationship between fat and bone, evaluating both potential positive and negative influences between adipose and bone tissue. It will also focus on the hypothesis that @entity170 might be considered the @entity28 of bone.
