Fig. 4.

CLA isomers differently affect coupling efficiency in the liver mitochondria of L-fed rats. The liver mitochondrial respiration rates were evaluated in the presence of succinate (A) or palmitoyl-carnitine (B) as substrates. CS activity was measured in the liver homogenate and mitochondrial fractions of differently treated rats; the mitochondrial protein mass was then calculated as the ratio between CS activity in the homogenate and isolated mitochondria (C). The basal and palmitate-induced proton leak from L (black), L9 (green), L10 (blue), or CD animals (red) (D, E) were measured in isolated hepatic mitochondria. Representative immunoblot of cytochrome C and UCP2 levels in liver mitochondria (C and F, insert, respectively) from differently treated rats; the bands were quantified using densitometric analysis from triplicate experiments, and the values were expressed as average fold increase (± SD) as compared with CD (F). The CPT activity (G), intracellular H₂O₂ yield (H), and basal aconitase/total aconitase ratios were reported (I). The results are expressed as the means ± SD from triplicate analyses from n = 7 animals/group. Differing superscript letters indicate statistically significant differences (P < 0.05).