MtDNA mutator mice have lower body mass and upregulated UCP2 levels.

<p>Body weight (A) and daily food consumption (B) in mtDNA mutator (mut) mice in comparison to littermate controls (wt) (n = 11). (C) Northern blot analyses of <i>Ucp2</i> levels in spleen, heart, brain and liver. (D) Fold change of <i>Ucp2</i> transcript levels in spleen, heart, brain, liver and hypothalamus for wt and mut (n = 4). (E) Western blot analyses of UCP2 in spleen and heart mitochondria of wt, mut and UCP2-deficient (ko) mice. (F) Proton motive force (bars) and mitochondrial matrix volume (lines) in liver and spleen mitochondria (n = 3). (G) Mean lifespan of wt, mut, ko and dm mice. All analyses were performed on 25-week-old mice. Bars indicate mean level ± standard error of the mean (S.E.M.). Asterisks indicate level of statistical significance (*p<0.05 **p<0.01 ***p<0.001, Student's <i>t</i>-test).