Figure 1.

3 days of high-fat feeding lowered lipid substrate contribution to respiration and stimulated reactive oxygen species production. Mitochondrial respiration of isolated mitochondria from quadriceps muscle during sequential additions of substrates and inhibitors. (A) Rates of oxygen consumption expressed relative to protein content (pmol O₂/μg protein/sec) from mice fed low-fat or high-fat diet for 3 days. (B) Rates of oxygen consumption expressed relative to protein content (pmol O₂/μg protein/sec) from mice fed low-fat or high-fat diet for 7 days. (C) Contribution of lipid-supported oxidation expressed as a percentage of maximal respiration measured after FCCP. (D) Electron leak to H₂O₂ calculated from H₂O₂ emission during lipid-supported oxidative phosphorylation and expressed as a percentage of oxygen consumption. Data are means ± SD; n=4-5. Repeated measures ANOVA with Tukey’s post-hoc tests were used to analyze data in (A, B). Two-way ANOVA was used to test for effects of diet and time in (C, D). P values are main effects.