ABSTRACT
Aim To investigate glutamate-induced [ Ca2 + ] i changes in cultured rat neonatal cortical astrocytes after hypoxia/reoxygenation, H2O2 or high concentration of L-glutamate injury. In the meantime, the effects of Gingko biloba extract (GbE) were examined. Methods [ Ca2+ ]i changes in astrocytes were monitored by laser scanning confocal microscopy with the Ca2+ sensitive fluorescent probe [ Ca2 + ] i, but decrease by ( 3.3 ± 1.6) %, (81 ± 11 ) % and ( 81 ± 7 ) %, respectively. Pretreatment with H2O2 or high concentration of L-glutamate injury were ( 135 ± 98 ) %, ( 117 ± 93 ) % and ( 89 ± 36) %,different injury. Conclusion Hypoxia/reoxygenation, H2O2 and high concentration of L-glutamate impaired astrocytes' response to exogenous L-glutamate, and then bidirectional communication between astrocytes and neurons could not take place. GbE could improve the abnormal responses and maintain the normal function of astroglical network. These effects support that GbE has potential beneficial actions against brain injury.
ABSTRACT
PURPOSE: Gingko biloba extract (GBE), a natural product extracted from Gingko leaves, is known to increase the radiosensitivity of tumors. This radiosensitization probably arises from the increase in the peripheral blood flow by decreasing the blood viscosity and relaxing the vasospasm. The influence of a GBE on the metabolic status in fibrosarcoma II (FSaII) of a C3H mouse was investigated using 31P magnetic resonance spectroscopy (MRS). MATERIALS AND METHODS: Eighteen C3H mice with fibrosarcoma II (from 100 mm3 to 130 mm3) were prepared for this experiment. The mice were divided into 2 groups; one (9 mice) without a priming dose, and the other (9 mice) with a priming dose of GBE. The GBE priming dose (100 mg/kg) was administered by an intraperitoneal (i.p.) injection 24 hours prior to the measurement. First 31P MRS spectra were measured in the mice from each group as a baseline and test dose of GBE (100 mg/kg) was then administered to each group. One hour later, the 31P MRS spectra were measured again to evaluate the change in the energy metabolic status. RESULTS: In the group without the priming dose, the mean pH, PCr/Pi, PME/ATP, Pi/ATP, PCr/(Pi+ME) values 1 hour after the test dose were not changed significantly compared to the values at the baseline. However, in the group with the priming dose, the mean PCr/Pi, Pi/ATP, PCr/(Pi+PME) values 1 hour after the test dose changed from the baseline values of 0.49, 0.77, 0.17 to 0.74, 0.57, 0.28 respectively. According to the paired t-test, the differences were statistically significant. CONCLUSION: The above findings suggest that the metabolic status is significantly improved after administering GBE if the priming dose is given 24 hours earlier. This shows that the radiosensitizing effect of GBE is based on the increase of tumor blood flow and the improvement in the metabolic status.
Subject(s)
Animals , Mice , Blood Viscosity , Energy Metabolism , Fibrosarcoma , Ginkgo biloba , Hydrogen-Ion Concentration , Magnetic Resonance Spectroscopy , Mice, Inbred C3H , Radiation Tolerance , Radiation-Sensitizing AgentsABSTRACT
Objective To investigate the protective effect of Gingko Biloba extract (GBE) on acute lung hemorrhage induced by Lipopolysaccharide(LPS) in newborn rats. Methods 1. Acute lung hemorrhage models were reproduced by intraperitoneal injection with LPS (5 mg/kg). 2. Thirty two rats were randomly divided into 4 groups,GBE groups (4 mg/kg,8 mg/kg, 16 mg/kg) and LPS group 5 mg/kg. Results In group LPS, extensive lung hemorrhage was observed after 4 hours of injection . TNF - ? iung content was obvious in LPS group. The expression of lung nuclear factor(NF-kB )immunohistochemistry wasobvious. While the parameters were obviously attenuated by GBE before LPS. Conclusion GBE may be useful in the treatment of acute pulmonary inflammatory disease.