Whereas obesity in childhood has been associated with greater quantitative parameters of bone (i.e., mineral content and density), fracture is overrepresented among obese youth suggesting impairments in bone quality. The association between increased fracture and obesity has been attributed to greater rate of falls due to poor balance, increased impact during falls due to excess weight, abnormal loading of the bones and joints and decreased physical activity impeding growth of skeletal muscle among obese children. While these factors warrant consideration, evaluation of the relationship largely focused on bone mineral content and/or density estimated from assessment of the outer surface of the bone, have failed to delineate a potential causal mechanism. The strength of bone is dependent upon size and structure as well as qualitative aspects, suggesting a need for evaluation of the inner surface of the bone, including the marrow compartment. The marrow compartment is largely comprised of red, hematopoietic marrow and yellow fatty marrow. In aging, the fatty elements in the marrow increase as does the composition of the marrow. A change in composition leads to a change in function. Importantly, the variety of secretory factors synthesized and released by adipocytes within the bone marrow adipose tissue (BMAT), change with aging and in disease states. Thus the marrow compartment represents an auspicious area of investigation underlying long-term bone health.
The historical view of bone marrow adipose tissue (BMAT) as simply a âfillerâ void of function has been reconsidered, with more recent implications suggesting that appearance of adipose within the marrow is a pathogenicconsequence of suppressed (inner) bone formation.As the greatest rate of the natural course of conversion from hematopoietic marrow to BMAT in long bones occurs at the same time bone growth peaks, converging metabolic pathways to optimize skeletal integrity may have the greatest impact on long-term bone health.
Krista Casazza, Bone Marrow Adipose Tissue in Adolescence- Protective or Pathogenic
Last date updated on July, 2014