title: Preconditioning of brain slices against hypoxia induced injury by a Gynostemma pentaphyllum extract--stimulation of anti-oxidative enzyme expression.
abstract: A short period of hypoxia/hypoglycaemia (oxygen and glucose deprivation, OGD) induced by perfusion with O(2)/glucose-free medium caused immediate loss and incomplete restoration of evoked field potentials in the CA1 region of transverse hippocampus slices. OGD-dependent decrease in evoked field potentials can be prevented by a proceeding short OGD event (preconditioning). We report about a study investigating the effect of an ethanolic Gynostemma pentaphyllum extract on evoked field potentials when administered before the OGD episode. Using this procedure, the extract completely protected the cells of the slices from functional injury. In an astroglia rich cell culture the ethanolic Gynostemma pentaphyllum extract caused within 48 h of cultivation increased protein and activity levels of the anti-oxidative enzymes manganese superoxide dismutase (Mn-SOD) and glutathione peroxidase (GPx). Consequently, the cellular H(2)O(2) concentration remained at a low level. These data suggest that the Gynostemma pentaphyllum-mediated increase in antioxidative enzyme activities may contribute to the protection of transverse hippocampus slices from OGD induced functional injury. Our results demonstrate that the prophylactic administration of the ethanolic extract from Gynostemma pentaphyllum has a high potential to protect from ischemia/reperfusion injury.
authors.affiliation: Department of Pathological Biochemistry, Otto-von-Guericke-University, Magdeburg D-39120, Germany. lorenz.schild@med.ovgu.de
authors.forename: L
authors.initials: L
authors.lastname: Schild
authors.forename: T
authors.initials: T
authors.lastname: Cotte
authors.forename: G
authors.initials: G
authors.lastname: Keilhoff
authors.forename: R
authors.initials: R
authors.lastname: Brödemann
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000378:metabolism; D001921:Brain / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology*; D004353:Drug Evaluation, Preclinical / Q000379:methods; D005071:Evoked Potentials / Q000187:drug effects; D005947:Glucose / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D029774:Gynostemma / Q000737:chemistry*; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology; D006861:Hydrogen Peroxide / Q000378:metabolism; D000860:Hypoxia / Q000503:physiopathology*; D066298:In Vitro Techniques; D008297:Male; D010936:Plant Extracts / Q000494:pharmacology*; D020011:Protective Agents / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D015427:Reperfusion Injury / Q000503:physiopathology / Q000517:prevention & control*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D010936:Plant Extracts; D020011:Protective Agents; D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005947:Glucose