(A) Response surfaces showing the effect of dietary macronutrients on mitochondrial state IVo respiration with pyruvate as substrate (pmol O2 consumed/min/U of citrate synthase) in the liver at 15 months. Surfaces are shown for diet-based data (top), intake-based data (middle), and intake-based data adjusted to lean body mass (bottom). The highest activity is indicated in red (low-protein diets), and the lowest is indicated in blue.
(B) Response surfaces showing the effect of dietary macronutrients on mitochondrial state IVo respiration with palmitoyl carnitine as substrate (pmol O2 consumed/min/U of citrate synthase) in the liver at 15 months. Surfaces are shown for diet-based data (top), intake-based data (middle), and intake-based data adjusted to lean body mass (bottom). The highest activity is indicated in red (high-fat diets), and the lowest is indicated in blue. See also Figure S4 and Tables S6 and S7.