GLI1 and ischemia: The importance of the Hh pathway in the pathophysiology of the EPC compartment has been recently further strengthened by the demonstration that Gli1 and Ptch expression are reduced in the EPCs of streptozotocin (STZ)-induced type 1 diabetic mice and that administration of an Shh pathway receptor agonist (SAG) restores both the number and function of EPCs and increases neovascularization in these mice in response to ischemia [37].