Figure 2. Age-related alterations in expression of mitochondrial and anti-oxidative enzymes. Expression of proteins related to mitochondrial function in non-diseased hearts in young and old men (m) and women (w). Western blot analysis and statistical analysis of (A) TFAM, (B) PGC1-α, (C) TOM40, (D) Sirt3, (E) SOD2 and (F) catalase protein expression. Proteins were normalized to tubulin or actin. Data are shown as the mean ± SEM (n= 6-9/group). Representative imaging of western blot analysis; the lanes were run on the same gel. All data were normalized to the corresponding control and expressed in relative units (r.u.).