Methyltriphenylphosphonium (TPMP) salts have been widely used to measure the mitochondrial membrane potential and the triphenylphosphonium (TPP+) moiety has been attached to many bioactive compounds including antioxidants to target them into mitochondria thanks to their high affinity to accumulate in the mitochondrial matrix. The adverse effects of these compounds on cellular metabolism have been insufficiently studied and are still poorly understood. Micromolar concentrations of TPMP cause a progressive inhibition of cellular respiration in adherent cells without a marked effect on mitochondrial coupling. In permeabilized cells the inhibition was limited to NADH-linked respiration. We found a mixed inhibition of the Krebs cycle enzyme 2-oxoglutarate dehydrogenase complex (OGDHC) with an estimated IC50 3.93 [3.70-4.17] mM, which is pharmacologically plausible since it corresponds to micromolar extracellular concentrations. Increasing the lipophilic character of the used TPP+ compound further potentiates the inhibition of OGDHC activity. This effect of TPMP on the Krebs cycle ought to be taken into account when interpreting observations on cells and mitochondria in the presence of TPP+ derivatives. Compounds based on or similar to TPP+ derivatives may also be used to alter OGDHC activity for experimental or therapeutic purposes.
- MeSH
- buněčné linie MeSH
- citrátový cyklus účinky léků MeSH
- citrátsynthasa účinky léků metabolismus MeSH
- glutamátdehydrogenasa účinky léků metabolismus MeSH
- isocitrátdehydrogenasa účinky léků metabolismus MeSH
- ketoglutarátdehydrogenasový komplex antagonisté a inhibitory metabolismus MeSH
- kosterní svaly enzymologie MeSH
- krysa rodu rattus MeSH
- malátdehydrogenasa účinky léků metabolismus MeSH
- membránový potenciál mitochondrií účinky léků MeSH
- oniové sloučeniny farmakologie MeSH
- potkani Wistar MeSH
- pyruvátdehydrogenasový komplex účinky léků metabolismus MeSH
- svalové mitochondrie účinky léků enzymologie MeSH
- tritylové sloučeniny farmakologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
