Figure 7
Hippocampal-specific mitochondrial dysfunction in the young SCA1 mice. (a) Design of a substrate-uncoupler-inhibitor titration protocol for measuring the mitochondrial respiratory capacity. (b) Specific enzymatic activity of citrate synthase in the cerebellar and hippocampal tissues (log 2 [mIU/mg of tissue]). (c) Mitochondrial respiration (pmol O2/s/mg of homogenized tissue) in different states of the substrate-uncoupler-inhibitor protocol, reflecting complex I OXPHOS capacity in the ADP-activated state of oxidative phosphorylation (P I), complex I + II OXPHOS capacity (P I + II), maximum capacity for electron transport (E I + II), complex II uncoupled capacity (E II) and complex IV capacity, separately for the cerebellum (Cb) and the hippocampus (Hp) and for the WT (N = 5) and SCA1 (N = 6) mice (11–13 weeks of age; 4 samples for each mouse and brain structure). Box-whisker plots (b,c) indicating the inter-quartile (IQ) intervals (box), 1.5*IQ range (whiskers) and medians (middle lines). Each point = 1 sample. *P < 0.05, **P < 0.01, ***P < 0.001. n.s. = not significant. P-values were based on the permutational linear mixed-effect models (Suppl. Tables S27) using 4 samples per animal and with the animal identity representing the random-effect factor. See Suppl. Methods for the abbreviations.
