CASP3 and Friedreich ataxia: Our present study is the first one to demonstrate that injection of hUC-MSCs can improve renal function in NOD-SCID mice suffering from FA-induced AKI by modulating the mitochondrial and common pathways of apoptosis (reducing caspase-3 and -9, but not caspase-8), as well as promoting proliferation and decreasing apoptosis of renal tubular cells.