The effect of Leonurus cardiaca herb extract and some of its flavonoids on mitochondrial oxidative phosphorylation in the heart.
Level 5 - mechanism / opinion, no new human data
In vitro laboratory experiment on isolated cardiac mitochondria
PubMed 24841965 · doi:10.1055/s-0034-1368426
What was done
Ethanolic extract of Leonurus cardiaca (motherwort) aerial parts was analyzed by HPLC to determine polyphenol constituents (chlorogenic acid, orientin, quercetin, hyperoside, rutin). The extract and constituents were evaluated for effects on cardiac mitochondrial respiration rates using a Clark-type oxygen electrode and on mitochondrial reactive oxygen species (ROS) production fluorimetrically using Amplex Red and horseradish peroxidase.
What was found
Constituents of L. cardiaca herb extract uncoupled mitochondrial oxidation from phosphorylation by 20% to 90%, partially inhibited the mitochondrial respiratory chain by ~40% during both pyruvate/malate and succinate oxidation, and attenuated mitochondrial free radical generation.
Why it matters
This study provides an in vitro mechanistic basis (partial mitochondrial uncoupling, mild respiratory inhibition, and ROS reduction) that may explain the cardioprotective actions attributed to motherwort extract.
Limits
The study is entirely in vitro on isolated mitochondria, with no in vivo pharmacokinetic, bioavailability, or clinical validation. Sample sizes, biological replicates, and the donor species for cardiac mitochondria are not specified in the abstract.
Cited by
- supports Polyphenols act as mitochondrial uncouplers.