Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9038662 | Toxicology in Vitro | 2005 | 9 Pages |
Abstract
SH-SY5Y human neuroblastoma cells were incubated with 6-hydroxydopamine (6-OHDA) for 4 and 24 h to examine the mechanism of cell death and to determine the time-dependent effects of 6-OHDA on cellular glutathione status. After 4 h, 6-OHDA significantly depleted cellular ATP and GSH concentrations with only slight increases in cell death. GSH:GSSG ratios and mitochondrial membrane potential (ÎÏm) were significantly decreased during 4 h incubations with 6-OHDA. High concentrations of 6-OHDA (⩾100 μM) induced oxidative stress and mitochondrial dysfunction in SH-SY5Y cells within 4 h leading to cell death. In 24 h incubations, 25 and 50 μM 6-OHDA significantly decreased ATP concentrations; however, significant increases in cell death were only observed with 50 μM 6-OHDA. 6-OHDA induced a concentration-dependent increase in GSH and total glutathione concentrations after 24 h. After exposure to 50 μM 6-OHDA, GSH concentrations were increased up to 12-fold after 24 h with no change in the GSH:GSSG ratio. Gene analysis suggests that the increase in GSH concentration was due to increased expression of the GSH synthesis genes glutamate cysteine ligase modifier and catalytic subunits. Our results suggest that 6-OHDA induces oxidative stress in SH-SY5Y cells resulting in an adaptive increase in cellular GSH concentrations.
Keywords
ROS reactive oxygen speciesDMEM, Dulbecco’s minimum essential mediumCCCP, carbonylcyanide-m-chlorophenylhydrazone6-HydroxydopamineGSS, glutathione synthetaseGsr, glutathione reductaseGCLC, glutamate cysteine ligase catalytic subunit6-OHDA, 6-hydroxydopamineGCL, glutamate cysteine ligaseOxidative stressLDH, lactate dehydrogenaseglutamate cysteine ligasePBS, phosphate buffered salinePotentialMitochondrial membrane potentialGlutathioneGPX, glutathione peroxidase
Related Topics
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Authors
Mark A. Tirmenstein, Catherine X. Hu, Marshall S. Scicchitano, Padma K. Narayanan, David C. McFarland, Heath C. Thomas, Lester W. Schwartz,