ABSTRACT
A standardized aqueous extract of Panax ginseng radix was tested for its antioxidant effect on primary astrocytes culture on an oxidant stress model generated by H(2)O(2). The results indicated that this extract had a significant effect on the reduction of astrocytic death induced by H(2)O(2). Dose-response experiments revealed that this ginseng extract increased cell viability at a wide range of concentrations. Therefore, we investigated the effects of this extract on antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), glutathione peroxidases (GPx) and glutathione reductase (GR), on glutathione content (reduced and oxidized forms and red/ox index) and on the intracellular reactive oxygen species (ROS) formation. Exposure of astrocytes to H(2)O(2) decreased the activities of antioxidant enzymes, and increased ROS formation. Ginseng root extract reversed the effect of almost all of these parameters in H(2)O(2)-injured primary cultures of rat astrocytes.
Subject(s)
Astrocytes/drug effects , Neuroprotective Agents , Panax/chemistry , Animals , Animals, Newborn , Antioxidants/metabolism , Ascorbic Acid/metabolism , Biological Transport, Active/drug effects , Cell Survival/drug effects , Cells, Cultured , Glucose/metabolism , Glutathione/metabolism , Hydrogen Peroxide/pharmacology , Lactic Acid/metabolism , Nerve Tissue Proteins/metabolism , Oxidants/pharmacology , Oxidative Stress/drug effects , Plant Extracts/pharmacology , Plant Roots/chemistry , Rats , Rats, Wistar , Reactive Oxygen Species/metabolismABSTRACT
The present research describes a reversed-phase high-performance liquid chromatographic (RP-HPLC) method that allows the determination of several amino acids in primary cultured cortical neurons of rats. The concentration of amino acids was determined by using pre-column derivatization with dansyl chloride and UV-diode array detection. Data show that Panax ginseng radix extract (GS) can modulate amino acid release in neurons. The levels of glutamate (Glu), aspartate (Asp), gamma-aminobutyric acid (GABA) and glycine (Gly) in the GS-treated groups were higher than in the non-treated groups dose-dependentwise. In this case, Glu and GABA were the most released amino acids (74.43% +/- 0.97 and 88.41% +/- 4.12 at ginseng dose 0.01 mg/ml after 1h from treatment, respectively). The values obtained in the determination of the analytical parameters (linearity, precision, limit of detection and accuracy) confirm the quality of the method. The average recoveries for intra and inter-day assay (n = 5) were 101.18 and 102.38 for Asp, 99.35 and 98.44 for Glu, 99.59 and 99.66 for Gly, and 100.06 and 100.37 for GABA. These data proved that the method yields accurate results, with RSD lower than 2.2%. The precision of the method was estimated on the basis of RSD of six injections at two different concentrations of amino acids. This technique is useful in studying the GS-mediated modulation of the dynamic equilibrium of amino acids and neurotransmission in neurons.