Research Paper Volume 1, Issue 9 pp 771—783
Diet and exercise signals regulate SIRT3 and activate AMPK and PGC-1α in skeletal muscle
Figure 2. Skeletal muscle-specific induction of SIRT3 and associated factors in exercise-trained mice. (A) Triceps or cardiac muscle tissue was homogenized and 50 μg of protein was analyzed by Western blot, using anti-SIRT3 serum (Covance) and α-tubulin control; representative blots are shown here and throughout. SED = sedentary and TRD = trained. (B) Quantification of SIRT3 band intensities using ImageQuant from blots with animals grouped by sex. Males are plotted as clear bars and females as shaded bars. Total number of animals used per cohort and graphed are as follows: sedentary males, N = 7; sedentary females, N = 5; exercised males, N = 8; exercised females, N = 6. (C) Phospho-CREB/Ser133 and total CREB protein. Band intensities of phospho-CREB and CREB were quantified and phospho-CREB content was normalized relative to total CREB content; inset provides sample blots of male triceps tissue. (D) Induction of PGC-1α correlates with enhanced SIRT3 expression in triceps; samples processed and analyzed, as above. Inset blots are of male triceps tissue. (E) Citrate synthase activity was measured as a mitochondrial marker from the same triceps samples, as described previously [