Fig. 5.

Hfd increases mitochondrial H₂O₂ production and catalase activity with no effect of fish oil. H₂O₂ production was measured in isolated mitochondria under state 4 conditions by spectrofluorometer, expressed relative to tissue wet weight (A) and relative to mitochondrial protein content (B). H₂O₂ emission was measured in permeabilized muscle fibers during a stepwise increase in succinate under state 4 conditions. Gene transcript levels (D) of superoxide dismutase-1 (SOD1), superoxide dismutase-2 (SOD2), catalase (CAT), and glutathione peroxidase (GPX1) were measured in muscle tissue at 10 wk. Activity of catalase (E) and total SOD (F) were measured spectrophotometrically. Skeletal muscle oxidative damage (G) was determined from 8-oxo-2′-deoxyguanosine (8-oxo-dG), a major product of DNA oxidation measured by mass spectrometry. Bars represent means ± SE for NFD, HFD, and HFD+FO. *Significant statistical differences from NFD; #significantly different from HFD (P < 0.05, Tukey's HSD).