Duicu 2013 Mol Cell Biochem
|Duicu O, Juşcă C, Falniţă L, Mirică S, Maximov D, Firă-Mladinescu O, Muntean D (2013) Substrate-specific impairment of mitochondrial respiration in permeabilized fibers from patients with coronary heart disease versus valvular disease. Mol Cell Biochem 379:229-34.|
Abstract: High-resolution respirometry of permeabilized myocardial fibers offers reliable insights concerning the integrated mitochondrial function while using small amounts of cardiac tissue. The aim of the present study was to assess the respiratory function in permeabilized fibers of human right atrial appendages harvested from patients with coronary heart disease (CHD) (n = 6) versus patients with valvular disease (n = 5) and preserved ejection fraction that underwent non-emergency cardiac surgery. Human bundle samples (1-3 mg wet weight) permeabilized with saponin were transferred into the 2 ml Oxygraph-2 k chambers to measure complex I(CI) and II (CII)-dependent respiration, respectively. The following values (expressed in pmol/s mg) were obtained for CI-dependent respiration: oxidative phosphorylation (OXPHOS), 35.65 ± 1.10 versus 42.43 ± 1.08, electron transport system (ET-pathway), 37.87 ± 1.72 versus. 46.58 ± 1.85, and respiratory control ratio (RCR, calculated as the ratio between OXPHOS and LEAK states), 2.43 ± 0.09 versus 2.73 ± 0.068 (p < 0.05). In conclusion, in patients with CHD we showed a significant decline for the OXPHOS capacity, ET-pathway and RCR for mitochondria energized with CI (but not with CII) substrates. These observations are suggestive for an early impairment of complex I supported respiration in ischemic heart disease, as previously demonstrated in the setting of experimental ischemia/reperfusion in several animal species.
• Keywords: Human atrial permeabilized fibers; High-resolution respirometry; Coronary heart disease; Valvular disease
• O2k-Network Lab: RO Timisoara Muntean DM
Organism: Human Tissue;cell: Heart Preparation: Permeabilized tissue
Pathway: N, S HRR: Oxygraph-2k