Obesity and the relationship between somatotrophic axis and bone tissue

In postmenopausal obese women often is observed increase bone mineral density in relation to slim women. Dominate the view that positive influence of adipose tissue on state of skeleton in postmenopausal women can be consequence of the boost to load carrying bone, may also result from the role of adipose tissue as endocrine organ. Interaction existence between somatotrophic axis and bone tissue suggests that revealing itself changes of constituents concentration of this axis in obesity individuals may have significance in bone tissue remodeling modification after menopause. It has been demonstrated that GH and IGF-I secretion decrease with age and this changes are major in obesity persons, particularly in women, and they depend on BMI and the percentage of body fat content. GH as well as IGF-I may directly and indirectly modulate bone remodeling, stimulating both bone formation and bone resorption. In the light of latest data this last effect is realized through their influence on expression of OPG and/or RANKL, cytokines belonging to the family of tumor necrosis factor-alpha, which provide important controlling process element of the numbers of activated osteoclasts through osteoblasts. (Pol J Endocrinol 2009; 60 (4): 302-309)