The Effect Of Resveratrol On The Cell Proliferation,S100B Secretion And The Function Of Glutamate Metabolism In Primary Cortical Astrocytes Cultures Of Rats

Objective (1)To investigate the effect of different concentrations of resveratrol on the cell proliferation,glutamate uptake,glutamate transporters, glutamine synthetase and glutathione content in primary cortical astrocytes of rats and the possible mechanism. (2) To investigate the effect of different concentrations of resveratrol on the S100B transcription and secretion.Then to further discuss the mechanism of protection of resveratrol to nerve cells, and provide theory reference of clinical treatment.Methods Astrocyte cultures were prepared of cerebral cortex from neonate SD rats. Morphology was evaluated by phase-contrast microscopy and immunocytochemistry for GFAP. Astrocytes were incubated for 24h in DMEM without serum in the absence or presence of resveratrol at concentrations of 1,10,25,50,100 and 250μmol/L.The proliferation was measured by the incorporation of BrdU; Glutamate uptake was measured using H3-glutamate ;the content and activity of glutamine synthetase , content of glutathione and S100B secretion were measured by ELISA. The GLAST mRNA and GLT-1 mRNA was measured by real time fluorescent quantitation PCR.Results The purity of the astrocytes was more than 95%.The proliferation was decreased,and followed by the concentration and time.At concentration of 25μmol/L and 50μmol/L, resveratrol was able to increase glutamate uptake and glutathione content(P<0.05),but more than 250μmol/L, they decreased.But at this high concentration , glutamine synthetase activity and content were increased(P<0.05). At 0-100μmol/L there were no significant changes(P>0.05).The GLAST mRNA and GLT-1 mRNA didn,t change when the concentration was less than 50μM,whereas they decreased at the concentration more than 100μM.The secretion of S100B was increased significantly at 50μmol/L,100μmol/L,250μmol/L(P<0.05),the mRNA was increased significantly at the same concentrations(P<0.05).But at 10μmol/L and 25μmol/L ,the S100B mRNA didn't change significantly(P>0.05).Conclusion The resveratrol can inhibit cell roliferation;and it has dual effect on glutamate uptake, depending on its concentration.At low concentration it has antioxidant properties ,so it can promote the glutamate uptake ,increase GSH and S100B.It can protect the nerve cell from injuries, particularly those involving glutamate toxicity.The high concentration is opposite.