PPARGC1A and Friedreich ataxia: We have observed up-regulation of the phosphorylated active form of both p38 MAPK and AMPK kinases in fibroblasts from FRDA 1 and FRDA 2 patients but not in FRDA 3 cells or control cell lines, indicating that it is a feasible phenomenon involved in the activation of PGC-1α (Figure 5A).