Relationships between maximal mitochondrial oxidative phosphorylation, HO-1 expression, and AMPK activation. Maximal oxidative phosphorylation plotted as a function of HO-1 expression (A) and of AMPK activation (B), and HO-1 expression plotted as a function of AMPK activation (C). Hyperglycemic animals (squares) are shown on the left, normoglycemic mice (circles) on the right panels each; vehicle-treated mice are represented by open symbols and EMD008-treated animals by black symbols. Overall correlation between mitochondrial oxidative phosphorylation, HO-1 expression, and AMPK activation was r = 0.15 (p = 0.47) and r = 0.2 (p = 0.31), respectively. Overall correlation between HO-1 expression and AMPK activation was r = 0.33 (p = 0.098). Due to technical difficulties, the number of observations was reduced in the normoglycemic groups, which limits the statistical reliability of the evaluation.