title: Neuroprotection against neuroblastoma cell death induced by depletion of mitochondrial glutathione.
abstract: Mitochondrial glutathione pool is vital in protecting cells against oxidative stress as the majority of the cellular reactive oxygen species are generated in mitochondria. Oxidative stress is implicated as a causative factor in neuronal death in neurodegenerative disorders. We hypothesized that depletion of mitochondrial glutathione leads to mitochondrial dysfunction and apoptotic death of SK-N-SH (human neuroblastoma) cells and investigated the neuroprotective strategies against GSH depletion. SK-N-SH cells were treated with two distinct inhibitors of glutathione metabolism: L-buthionine-(S, R)-sulfoximine (BSO) and ethacrynic acid (EA). EA treatment caused depletion of both the total and mitochondrial glutathione (while BSO had no effect on mitochondrial glutathione), enhanced rotenone-induced ROS production, and reduced the viability of SK-N-SH cells. Glutathione depletion by BSO or EA demonstrated positive features of mitochondria-mediated apoptosis in neuroblastoma cell death. Prevention of apoptosis by Bcl2 overexpression or use of antioxidant ebselen did not confer neuroprotection. Co-culture with U-87 (human glioblastoma) cells protected SK-N-SH cells from the cell death. Our data suggest that depletion of mitochondrial glutathione leads to mitochondrial dysfunction and apoptosis. The study indicates that preventing mitochondrial glutathione depletion could become a novel strategy for the development of neuroprotective therapeutics in neurodegenerative disorders.
authors.affiliation: Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, Division of Health Sciences and Biomedical Research Institute, Idaho State University, Pocatello, ID 83209-8334, USA. v.dukhande@uky.edu
authors.forename: Vikas V
authors.initials: VV
authors.lastname: Dukhande
authors.forename: Ivana
authors.initials: I
authors.lastname: Kawikova
authors.forename: Alfred L M
authors.initials: AL
authors.lastname: Bothwell
authors.forename: James C K
authors.initials: JC
authors.lastname: Lai
mesh_terms: D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology; D001393:Azoles / Q000494:pharmacology; D019328:Buthionine Sulfoximine / Q000494:pharmacology; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D018920:Coculture Techniques; D045304:Cytochromes c / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D004976:Ethacrynic Acid / Q000494:pharmacology; D005909:Glioblastoma / Q000378:metabolism / Q000473:pathology; D005978:Glutathione / Q000378:metabolism*; D006801:Humans; D054833:Isoindoles; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism; D009447:Neuroblastoma / Q000378:metabolism / Q000473:pathology; D009474:Neurons / Q000502:physiology*; D016566:Organoselenium Compounds / Q000494:pharmacology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D001393:Azoles; D054833:Isoindoles; D016566:Organoselenium Compounds; D019253:Proto-Oncogene Proteins c-bcl-2; D017382:Reactive Oxygen Species; D051028:bcl-2-Associated X Protein; C042986:ebselen; D019328:Buthionine Sulfoximine; D045304:Cytochromes c; D005978:Glutathione; D004976:Ethacrynic Acid