The Effect of Ginkgo biloba extract on mitochondrial oxidative phosphorylation in the normal and ischemic rat heart

Jurga Bernatoniene (1) , Daiva Majiene (2) , Rimantas Peciura (2) , Ale Laukeviciene (2) , Ruta Bernatoniene (2) , Dalia Kopustinskiene (2) , Tauras Mekas (3) , Arturas Kasauskas (4)

1 department of Drug Technology and Pharmaceutical Management
2 Kaunas University of Medicine
3 Department of Drug Technology and Social Pharmacy
4 Department of Biochemisty

Free radicals-induced myocardial damage and impairment of vascular endothelium-dependent relaxation are amongst the most important mechanisms responsible for the ischemic heart injury. Ginkgo biloba leaf extract (GE) has been reported to improve blood circulation in the brain and have beneficial impact on the cardiovascular system but its cardioprotective effects have not been elucidated yet. Therefore, in this study we investigated the influence of GE in 70% ethanol (1:5) administered orally to rats on the functions of isolated heart mitochondria under normal and ischemic conditions. Wistar rats were given GE or ethanol (solvent control) at a dosage of 0.32 mL/kg in drinking water for 10 and 18 days, while control animals received untreated drinking water. Mitochondrial respiration rates were determined oxygraphically. Pyruvate and malate, succinate or palmitoyl-L-carnitine and malate were used as substrates. GE treatment partially uncoupled mitochondrial oxidation from phosphorylation, reduced generation of free radicals in the mitochondria, diminished ischemia-induced V3 decrease and the degree of respiration stimulation by exogenous cytochrome c. Thus, these results indicate that GE exerts cardioprotective effects reducing ischemia-caused impairment of the functions of heart mitochondria.

Mots clés: Life Sciences

Jurga Bernatoniene, Daiva Majiene, Rimantas Peciura, Ale Laukeviciene, Ruta Bernatoniene, et al.. The Effect of Ginkgo biloba extract on mitochondrial oxidative phosphorylation in the normal and ischemic rat heart. Phytotherapy Research, 2011, ⟨10.1002/ptr.3399⟩. ⟨hal-00613791⟩