Research Paper Volume 6, Issue 4 pp 296—310

Figure 2. Mitochondria from LLI are defective but maintain a high bioenergetic efficiency. The olygomycin-sensitive ATP synthesis rate (nmol/min/10⁶ cells) was measured in permeabilized cells energized with either glutamate-malate (A) or succinate (C). To correct for mitochondrial mass, the citrate synthase activity was used to normalize the OXPHOS rate obtained in the presence of either glutamate-malate (B) or succinate (D). Data are presented as the mean value ± SD. Two independent experiments were performed on DFs of each donor. The histograms show the mean value ± SD of two independent experiments. *p<0.05 LLI vs both Young and Old. (E) Representative dot plots for the analysis of MMP of DFs from Young, Old, or LLI, by using JC-1. In all the three cases, the percentage of cells with depolarized mitochondria (JC-1 monomers, right to the red bar) is less than 1%. Flow cytometric analysis of intracellular O₂⁻ (F), GSH (G) and H₂O₂ content (H). Each histogram represents a sample of DFs from Young, Old or LLI. No difference was observed in O₂⁻ and GSH levels; H₂O₂ content was higher in three out of four assayed LLI. (I) Intracellular ATP content expressed as nmol/10⁶ cells. Data are presented as the mean value ± SD. Two independent experiments were performed on DFs of each donor. *p<0.05 LLI vs Old and **p<0.01 LLI vs Young.