Aging Clin Exp Res. 2010 Aug 27. [Epub ahead of print]
Effect of Ginkgo biloba extract (EGb 761) on parameters of oxidative stress in different regions of aging rat brain after acute hypoxia.
Institute of Laboratory Medicine, Clinical Chemistry, and Molecular Diagnostics, Department of Medicine, University of Leipzig.
Background and aims:
Neurodegenerative processes of aging shall be associated with oxidative stress by reactive oxygen species (ROS).
This study investigates the influence of age and of acute respiratoric hypoxia on parameters of oxidative stress in different brain regions of Wistar rats, and protective effects of Ginkgo extract (EGb 761) as radical scavenger.
Methods: Biopsies of frontal and temporal cortices, cerebellum and brainstem of young and old rats (each group n= 6-8 : normoxic-hypoxic; unprotected -EGb-protected) were analyzed for malondialdehyd (MDA) level, superoxid dismutase (SOD) activity, glutathion (GSH) content, and creatin kinase (CK) activity.
Experimental hypoxia: downregulation of oxygen partial pressure to 5 vol. % for 20 minutes. EGb application: daily 100 mg/kg b.w. in drinking water for 3 months. Results: Effects of age: In temporal cortex, cerebellum and brainstem most of the oxidative stress parameters are increased but not in frontal cortex; after additional hypoxia SOD and GSH are diminished in old temporal cortex and brainstem.
EGb-treatment causes contradictory alterations in young, old and hypoxic brain regions. Minor effects are seen in old hypoxic brain, some protective effects in old normoxic brainstem and cerebellum.
Conclusions: The old brain appears to be well adapted to chronic oxidative stress, but shows a sufficient adaptation to the specific conditions of short hypoxia, too. The EGb (Ginkgo extract) protecting effect is especially remarkable in brainstem and cerebellum.
PMID: 20802257 [PubMed - as supplied by publisher]