Effects of Systemic PPARγ Inhibition on Bone and Immune Cells in Aged Female Mice.

This study investigates the effects of peroxisome proliferator-activated receptor gamma (PPARγ) inhibition on bone and immune cell profile in aged female mice, as well as in vitro stromal stem cell (SSC) osteogenic differentiation and inflammation gene expression. The hypothesis was that inhibition of PPARγwould increase bone mass and alter immune and other cellular functions. Our results showed that treatment with PPARγantagonist GW9662 for six weeks reduced bone volume and trabecular number and increased trabecular spacing. However, inhibition of PPARγhad no significant effect on marrow and spleen immune cell composition in aged female mice. In vitro experiments indicated that GW9662 treatment increased the expression of osteogenic genes but did not affect adipogenic genes. Additionally, GW9662 treatment decreased the expression of several inflammation related genes. Overall, these findings suggest that PPARγinhibition may have adverse effects on bone in aged female mice.