Fatty Acid Oxidation and Mitochondrial Morphology Changes as Key Modulators of the Affinity for ADP in Rat Heart Mitochondria.
Adolfas ToleikisSonata TrumbeckaiteJulius LiobikasNeringa PauzieneLolita KursvietieneDalia Marija KopustinskienePublished in: Cells (2020)
Fatty acids are the main respiratory substrates important for cardiac function, and their oxidation is altered during various chronic disorders. We investigated the mechanism of fatty acid-oxidation-induced changes and their relations with mitochondrial morphology and ADP/ATP carrier conformation on the kinetics of the regulation of mitochondrial respiration in rat skinned cardiac fibers. Saturated and unsaturated, activated and not activated, long and medium chain, fatty acids similarly decreased the apparent KmADP. Addition of 5% dextran T-70 to mimic the oncotic pressure of the cellular cytoplasm markedly increased the low apparent KmADP value of mitochondria in cardiac fibers respiring on palmitoyl-l-carnitine or octanoyl-l-carnitine, but did not affect the high apparent KmADP of mitochondria respiring on pyruvate and malate. Electron microscopy revealed that palmitoyl-l-carnitine oxidation-induced changes in the mitochondrial ultrastructure (preventable by dextran) are similar to those induced by carboxyatractyloside. Our data suggest that a fatty acid oxidation-induced conformational change of the adenosine diphosphate (ADP)/adenosine triphosphate (ATP) carrier (M-state to C-state, condensed to orthodox mitochondria) may affect the oxidative phosphorylation affinity for ADP.
Keyphrases
- fatty acid
- oxidative stress
- diabetic rats
- hydrogen peroxide
- cell death
- electron microscopy
- reactive oxygen species
- endoplasmic reticulum
- high glucose
- diffusion weighted imaging
- left ventricular
- drug induced
- electron transfer
- protein kinase
- heart failure
- molecular dynamics simulations
- visible light
- single molecule
- electronic health record
- magnetic resonance
- atrial fibrillation
- single cell
- molecular dynamics
- mass spectrometry
- deep learning
- machine learning
- big data
- adverse drug
- stress induced
- artificial intelligence