FIGURE 7.

Catalase is uniquely up-regulated by fasting. Cardiac catalase protein concentration, activity, and mRNA levels were determined in mice either fed low fat control diet or fasted for 1 day. A, quantitative mass spectrometric analysis of antioxidant protein expression in mice fasted for 1 day relative to low fat-fed controls (dashed line). The abbreviations used are: aldo-keto reductase family 1 member B1 (Akr1b1), aldehyde dehydrogenase (Aldh2), catalase (Cat), glutathione peroxidase (Gpx), methionine sulfoxide reductase A (Mrsa), prohibitin (Phb), peroxiredoxin (Prdx), superoxide dismutase (Sod), thioredoxin (Txn), thioredoxin reductase (Txnrd). B, total catalase activity (H₂O₂ consumed per mg of total protein) in low fat-fed control mice (open bar) compared with mice fasted for 1 day (closed bar). C, catalase mRNA levels in mice maintained on low fat control diet or fasted for 1 day. D, ACOX1 protein concentration determined by quantitative mass spectrometry in mice fed low fat control diet or fasted for 1 day. Values are presented as the mean ± S.E. (catalase mRNA, Bio-Rad CFX manager software version 2.1) or mean ± S.D. (protein concentration and activity, 2-tailed t test), where * indicates a significant difference between low fat-fed and fasted mice (p < 0.05, n = 5).