[Do thiazolidinediones harm skeletal integrity?]

Thiazolidinediones (TZDs) , a class of drugs that potentiate insulin actions, are widely prescribed to patients with type 2 diabetes mellitus. TZDs are able to bind to and activate PPAR-gamma, a member of nuclear transcription factors, and have been found to be involved in differentiation of many types of cells in addition to improve glucose metabolism. In particular, TZDs possibly reduce bone formation in vivo , since they have been reported to stimulate adipogenesis but inhibit osteoblastogenesis of bone marrow stromal cells. Recently, it has been reported that female patients with type 2 diabetes who were treated with rosiglitazone, a member of TZDs, had higher fracture incident than those with metformin. These observations make us seriously consider if it is good or not to prescribe TZDs to patients with type 2 diabetes, especially older women who have multiple fracture risks.