EGb 761 protects liver mitochondria against injury induced by in vitro anoxia/reoxygenation.
The present study investigated the protective effects of Ginkgo biloba extract (EGb 761) on rat liver mitochondrial damage induced by in vitro anoxia/reoxygenation. Anoxia/reoxygenation was known to impair respiratory activities and mitochondrial oxidative phosphorylation efficiency. ADP/O (2.57 +/- 0.11) decreased after anoxia/reoxygenation (1.75 +/- 0.09, p < .01), as well as state 3 and uncoupled respiration (-20%, p < .01), but state 4 respiration increased (p < .01). EGb 761 (50-200 microg/ml) had no effect on mitochondrial functions before anoxia, but had a specific dose-dependent protective effect after anoxia/reoxygenation. When mitochondria were incubated with 200 microg/ml EGb 761, they showed an increase in ADP/O (2.09 +/- 0.14, p < .05) and a decrease in state 4 respiration (-22%) after anoxia/reoxygenation. In EPR spin-trapping measurement, EGb 761 decreased the EPR signal of superoxide anion produced during reoxygenation. In conclusion, EGb 761 specially protects mitochondrial ATP synthesis against anoxia/reoxygenation injury by scavenging the superoxide anion generated by mitochondria.
Du
G
G
Laboratory of Bioenergetics, Institute of Chemistry (B6C), University of Liège, Belgium.
Willet
K
K
Mouithys-Mickalad
A
A
Sluse-Goffart
C M
CM
Droy-Lefaix
M T
MT
Sluse
F E
FE
D000255:Adenosine Triphosphate / Q000096:biosynthesis; D000818:Animals; D004578:Electron Spin Resonance Spectroscopy; D005419:Flavonoids / Q000494:pharmacology*; D016166:Free Radical Scavengers / Q000494:pharmacology; D020441:Ginkgo biloba / Q000627:therapeutic use; D000860:Hypoxia / Q000473:pathology; D008297:Male; D008930:Mitochondria, Liver / Q000187:drug effects* / Q000473:pathology; D010085:Oxidative Phosphorylation / Q000187:drug effects; D010100:Oxygen / Q000494:pharmacology*; D010101:Oxygen Consumption / Q000187:drug effects; D008517:Phytotherapy; D010936:Plant Extracts; D010946:Plants, Medicinal; D051381:Rats; D017208:Rats, Wistar; D013113:Spin Labels; D013481:Superoxides / Q000494:pharmacology; D014969:Xanthine Oxidase; D000096983:Ginkgo Extract
D000255:Adenosine Triphosphate; D005419:Flavonoids; D016166:Free Radical Scavengers; D010100:Oxygen; D010936:Plant Extracts; D013113:Spin Labels; D013481:Superoxides; D014969:Xanthine Oxidase; C063170:Ginkgo biloba extract; D000096983:Ginkgo Extract