Figure 2.

Skeletal unloading decreases TGF-β expression and activates the expression of C/EBPα, C/EBPβ, and PPARγ2, resulting in activation of adipocyte gene expression such as adipocytic differentiation-related genes adipocyte binding protein (aP2) and lipoprotein lipase (LPL) in bone marrow stromal cells. Exogenous TGF-β2 (dotted lines) reduces C/EBPα, C/EBPβ, and PPARγ expressions, induces PPARγ phosphorylation (p-PPARγ), and increases Runx2 expression, resulting in decreased adipogenesis, increased osteoblast function, and prevention of bone loss.