Glutathione (GSH) and its associated enzymes comprise a major antioxidant system in brain. Neurodegenerative disease; including Parkinson's, ALS, Alzheimer's and Friedreich's ataxia involve oxidative damage and mitochondrial deficits. It is therefore, essential to develop an understanding of the roles served by GSH during mitochondrial impairment and oxidative insult. One little studied role for GSH is in protein-glutathione-mixed disulfide (PrSSG) formation, but has become of increasing interest as a mechanism for modulation of damage during oxidative stress. Previous work by us showed that during mitochondrial inhibition or oxidative stress, GSH is incorporated into protein to form PrSSG, a reversible reaction catalyzed by glutaredoxin (Grx). Importantly, we identified in brain mitochondria, functional Grx, an enzyme that could play a role in mitochondrial function or dysfunction during oxidative stress. A cytosolic form of Grx has been found in neurons. The overall objective of the current project is to expand our knowledge of the role and mechanism of protein thiolation and dethiolation during acute and chronic oxidative stress. The hypothesis to be examined is that during acute oxidative stress, PrSSG formation serves a reversible and protective function. In contrast, chronic long-term exposure to oxidative stress can result in impaired dethiolation that can contribute to neuronal damage.
Aim 1 will investigate cellular Grx and PrSSG formation during acute and chronic mitochondrial inhibition to determine if dethiolation is altered and if so, the underlying mechanism, and if enhancing Grx activity modulates neuronal viability during mitochondria inhibition. GSH and PrSSG have been linked to the ubiquitin proteasomal pathway.
This aim will also examine the effects of graded GSH depletion on this pathway under basal or oxidatively challenged conditions. Proteomics will be used to identify the major cellular proteins glutathionylated during oxidative stress Aim 2 will investigate mitochondrial Grx 8 PrSSG formation during mitochondrial impairment. We will expand on previous work during the past funding period to further examine the functional consequences of PrSSG formation in mitochondria and to determine in vivo the consequences of mitochondrial impairmenton mitochondrial Grx activity and PrSSG formation. Proteomics will be used to identify mitochondrial proteins that are glutathionylated during oxidative stress. Little is know regarding Grx in brain.
Aim 3 will characterize cytosolic Smitochondrial Grx and PrSSG levels with respect to age, gender and region and will determine i there are differences in Grx activity between synaptic and nonsynaptic mitochondria. Grx has not been identified in astrocytes.
This aim will also determine if astrocytes contain Grx or are capable of carrying out thiolation and dethiolation o proteins during oxidative stress. Overall, the project will generate novel information about a little studied role o GSH and its importance during mitochondrial impairment or oxidative stress. The studies will have relevance to neurodegenerative conditions or pathophysiological situations in which metabolism is compromised.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS036157-07
Application #
7013105
Study Section
Special Emphasis Panel (ZRG1-CDIN (01))
Program Officer
Sutherland, Margaret L
Project Start
1998-05-01
Project End
2009-03-31
Budget Start
2006-04-01
Budget End
2007-03-31
Support Year
7
Fiscal Year
2006
Total Cost
$303,496
Indirect Cost
Name
University of Medicine & Dentistry of NJ
Department
Neurology
Type
Schools of Medicine
DUNS #
617022384
City
Piscataway
State
NJ
Country
United States
Zip Code
08854
Gautam, Alpa H; Zeevalk, Gail D (2011) Characterization of reduced and oxidized dopamine and 3,4-dihydrophenylacetic acid, on brain mitochondrial electron transport chain activities. Biochim Biophys Acta 1807:819-28
Zeevalk, Gail D; Bernard, Laura P; Guilford, F T (2010) Liposomal-glutathione provides maintenance of intracellular glutathione and neuroprotection in mesencephalic neuronal cells. Neurochem Res 35:1575-87
Sonsalla, Patricia K; Zeevalk, Gail D; German, Dwight C (2008) Chronic intraventricular administration of 1-methyl-4-phenylpyridinium as a progressive model of Parkinson's disease. Parkinsonism Relat Disord 14 Suppl 2:S116-8
Zeevalk, Gail D; Razmpour, Roozbeh; Bernard, Laura P (2008) Glutathione and Parkinson's disease: is this the elephant in the room? Biomed Pharmacother 62:236-49
Domico, Lisa M; Cooper, Keith R; Bernard, Laura P et al. (2007) Reactive oxygen species generation by the ethylene-bis-dithiocarbamate (EBDC) fungicide mancozeb and its contribution to neuronal toxicity in mesencephalic cells. Neurotoxicology 28:1079-91
Zeevalk, G D; Manzino, L; Sonsalla, P K et al. (2007) Characterization of intracellular elevation of glutathione (GSH) with glutathione monoethyl ester and GSH in brain and neuronal cultures: relevance to Parkinson's disease. Exp Neurol 203:512-20
Yazdani, U; German, D C; Liang, C-L et al. (2006) Rat model of Parkinson's disease: chronic central delivery of 1-methyl-4-phenylpyridinium (MPP+). Exp Neurol 200:172-83
Zeevalk, Gail D; Bernard, Laura P (2005) Energy status, ubiquitin proteasomal function, and oxidative stress during chronic and acute complex I inhibition with rotenone in mesencephalic cultures. Antioxid Redox Signal 7:662-72
Gluck, Martin R; Zeevalk, Gail D (2004) Inhibition of brain mitochondrial respiration by dopamine and its metabolites: implications for Parkinson's disease and catecholamine-associated diseases. J Neurochem 91:788-95
Ehrhart, Julie; Zeevalk, Gail D (2003) Cooperative interaction between ascorbate and glutathione during mitochondrial impairment in mesencephalic cultures. J Neurochem 86:1487-97

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