Direct Effects of (−)‎-Epicatechin and Procyanidin B2 on the Respiration of Rat Heart Mitochondria

الملخص EN

Flavonol (−)-epicatechin and its derived dimer procyanidin B2, present in high amounts in cocoa products, have been shown to exert beneficial effects on the heart and cardiovascular system; however, their mechanism of action has not been fully elucidated.

We studied effects of (−)-epicatechin and procyanidin B2 on the oxidative phosphorylation of isolated rat heart mitochondria.

(−)-Epicatechin and procyanidin B2 had stimulating effect (up to 30% compared to control) on substrate-driven (State 2) mitochondrial respiration.

Their effect was dependent on the respiratory substrates used.

(−)-Epicatechin at higher concentrations (from 0.27 µg/mL) significantly decreased (up to 15%) substrate- and ADP-driven (State 3) mitochondrial respiration in case of pyruvate and malate oxidation only.

Procyanidin B2 (0.7–17.9 ng/mL) inhibited State 3 respiration rate up to 19%, the most profound effect being expressed with succinate as the substrate.

(−)-Epicatechin at concentrations of 0.23 µg/mL and 0.46 µg/mL prevented loss of the cytochrome c from mitochondria when substrate was succinate, supporting the evidence of membrane stabilizing properties of this flavonol.

Thus, both (−)-epicatechin and procyanidin B2 directly influenced mitochondrial functions and the observed effects could help to explain cardiometabolic risk reduction ascribed to the consumption of modest amounts of cocoa products.