Figure 3.
Decreased mitochondrial oxidative phosphorylation-OXPHOS complex I+II-linked respiration rate and maximal oxidative capacity in peripheral blood mononuclear cells of prostate cancer patients undergoing radiation therapy (n=15).
Notes: The X-axis indicates time points – day 0 (prior to radiation therapy) and day 21 (during radiation therapy); the Y-axis represents cell respiration rate (pmol O2/sec/106 cells). OXPHOS was measured as the ADP-stimulated respiration with malate, pyruvate, glutamate, and succinate as substrates, reflecting the convergence of complex I and II. OXPHOS-complex I+II-linked oxidation rate was significantly decreased at day 21 of radiation therapy (13.55 pmol O2/sec/106 cells, P=0.05) from day 0 of treatment (17.55 pmol O2/sec/106 cells). Uncoupled_FCCP1, uncoupled respiration rate – the maximal oxidative capacity was measured after the addition of an uncoupler-FCCP. Maximal uncoupled oxidation rate was decreased at day 21 of XRT (18.9 pmol O2/sec/106 cells, P=0.057) compared to prior treatment (16.3 pmol O2/sec/106 cells).
Abbreviations: ADP, adenosine diphosphate; FCCP, carbonylcyanide-p-trifluoromethoxyphenylhydrazone; OXPHOS, oxidative phosphorylation; XRT, radiation therapy.