6-Hydroxydopamine-induced glutathione alteration occurs via glutathione enzyme system in primary cultured astrocytes  

作　　者：JiZHANG JunHU Jian-huaDING Hong-hongYAO GangHU 

机构地区：[1]DepartmentofPharmacology,NanjingMedicalUniversity,Nanjing210029,China

出　　处：《Acta Pharmacologica Sinica》2005年第7期799-805,共7页中国药理学报（英文版）

基　　金：the National Natural Science Foundation of China(No 39970846).

摘　　要：Aim:To define the role of enzymes involved in glutathione metabolism in 6- hydroxydopamine(6-OHDA)-induced glutathione alteration in primary cultured astrocytes.Methods:Total glutathione(GSx)levels were determined using the modified enzymatic microtiter plate assay.The mRNA levels of γ-glutamylcysteine synthetase(γGCS),γ-glutamyltransferase(γGT),glutathione peroxidase(GPx),GR (glutathione reductase),and glutathione transferases(GST)were determined us- ing RT-PCR.γGT activity was determined using 7GT assay kits.Results:In primary cultured astrocytes,6-OHDA induced a significant elevation of cellular GSx levels after treatment for 24 h.However,the GSx levels decreased after 24 h and the values were even lower than the value in the control group without 6- OHDA at 48 h.RT-PCR data showed that the mRNA levels of γGCS,the rate- limiting enzyme of γ-L-glutamyl-L-cysteinylglycine(GSH)synthesis,were increased by 6-OHDA after treatment for 24 h and 48 h;the mRNA levels of GPx,GR,and GST did not alter in 6-OHDA-treated astrocytes after treatment for 24 h and 48 h;and 6- OHDA increased the mRNA levels and the activity of TGT after treatment for 48 h, which induced a decrease in GSx levels,despite the up-regulation of γCS after exposure to 6-OHDA for 48 h.Conclusion:The change in γGCS correlated with the increase in GSH levels induced by 6-OHDA after treatment for 24 h.GSx levels decreased because of increased γGT mRNA levels and γGT activity induced by 6- OHDA after treatment for 48 h.Aim:To define the role of enzymes involved in glutathione metabolism in 6- hydroxydopamine(6-OHDA)-induced glutathione alteration in primary cultured astrocytes.Methods:Total glutathione(GSx)levels were determined using the modified enzymatic microtiter plate assay.The mRNA levels of γ-glutamylcysteine synthetase(γGCS),γ-glutamyltransferase(γGT),glutathione peroxidase(GPx),GR (glutathione reductase),and glutathione transferases(GST)were determined us- ing RT-PCR.γGT activity was determined using 7GT assay kits.Results:In primary cultured astrocytes,6-OHDA induced a significant elevation of cellular GSx levels after treatment for 24 h.However,the GSx levels decreased after 24 h and the values were even lower than the value in the control group without 6- OHDA at 48 h.RT-PCR data showed that the mRNA levels of γGCS,the rate- limiting enzyme of γ-L-glutamyl-L-cysteinylglycine(GSH)synthesis,were increased by 6-OHDA after treatment for 24 h and 48 h;the mRNA levels of GPx,GR,and GST did not alter in 6-OHDA-treated astrocytes after treatment for 24 h and 48 h;and 6- OHDA increased the mRNA levels and the activity of TGT after treatment for 48 h, which induced a decrease in GSx levels,despite the up-regulation of γCS after exposure to 6-OHDA for 48 h.Conclusion:The change in γGCS correlated with the increase in GSH levels induced by 6-OHDA after treatment for 24 h.GSx levels decreased because of increased γGT mRNA levels and γGT activity induced by 6- OHDA after treatment for 48 h.

关 键 词：6-HYDROXYDOPAMINE GLUTATHIONE oxidative stress glutamate-cysteine ligase gammaglutamyltransferase 

分 类 号：R329.2[医药卫生—人体解剖和组织胚胎学]