The long-term goal of this investigation is to elucidate the mechanisms by which molecular oxidative damage causes losses in cellular functions during the aging process. In the current view, age-related attenuation in physiological functions is due to the accumulation of randomly- inflicted molecular oxidative damage. The proposed study will test an alternate hypothesis that """"""""senescence-associated losses in cellular functions are due to the accrual of oxidative damage to specific proteins."""""""" The validity of this hypothesis will be tested in different tissues of the mouse by determining whether an age-associated increase in oxidative damage and a loss in catalytic activity involve only a limited number of proteins and whether the amount of such damage and loss of protein function are related to the life expectancy of the animals. Life expectancy of the mice will be experimentally varied by caloric restriction. Protein oxidation will be detected by the presence of carbonyl groups.
Specific aims are: (1) Immunochemically detect carbonylated proteins in mitochondrial, microsomal and cytosolic fractions of various tissues in aged (24-month old) mice. (2) Quantify the age-associated increase in carbonylation of specific proteins in ad libitum-fed (AL) and calorically restricted (CR) mice. Select the proteins showing attenuation of carbonylation by CR (referred to here as 'CR-sensitive carbonylated proteins'.) (3) Purify and identify by microsequencing the 'CR-sensitive carbonylated proteins'. (4) Determine if carbonylated proteins lose catalytic activity during aging. (5) Elucidate mechanisms of carbonylation and loss of catalytic activity by determining the source of carbonylation and its effect on catalytic activity of the proteins. Results of this study should provide significant new information by indicating how oxidative molecular damage to specific proteins is mechanistically linked to senescence-associated losses in cellular functions. Results will also provide a test of the validity of oxidative stress hypothesis of aging.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Research Project (R01)
Project #
5R01AG013563-08
Application #
6509799
Study Section
Special Emphasis Panel (ZRG1-SSS-G (05))
Program Officer
Finkelstein, David B
Project Start
1996-04-01
Project End
2003-07-31
Budget Start
2002-04-01
Budget End
2003-07-31
Support Year
8
Fiscal Year
2002
Total Cost
$272,603
Indirect Cost
Name
University of Southern California
Department
Pharmacology
Type
Schools of Pharmacy
DUNS #
041544081
City
Los Angeles
State
CA
Country
United States
Zip Code
90089
Sohal, Rajindar S; Forster, Michael J (2014) Caloric restriction and the aging process: a critique. Free Radic Biol Med 73:366-82
Orr, William C; Radyuk, Svetlana N; Sohal, Rajindar S (2013) Involvement of redox state in the aging of Drosophila melanogaster. Antioxid Redox Signal 19:788-803
Sohal, Rajindar S; Orr, William C (2012) The redox stress hypothesis of aging. Free Radic Biol Med 52:539-555
Li, Xiao-Dong; Rebrin, Igor; Forster, Michael J et al. (2012) Effects of age and caloric restriction on mitochondrial protein oxidative damage in mice. Mech Ageing Dev 133:30-6
Rebrin, Igor; Forster, Michael J; Sohal, Rajindar S (2011) Association between life-span extension by caloric restriction and thiol redox state in two different strains of mice. Free Radic Biol Med 51:225-33
Bregere, Catherine; Rebrin, Igor; Gallaher, Timothy K et al. (2010) Effects of age and calorie restriction on tryptophan nitration, protein content, and activity of succinyl-CoA:3-ketoacid CoA transferase in rat kidney mitochondria. Free Radic Biol Med 48:609-18
Sohal, Rajindar S; Ferguson, Melissa; Sohal, Barbara H et al. (2009) Life span extension in mice by food restriction depends on an energy imbalance. J Nutr 139:533-9
Bregere, Catherine; Rebrin, Igor; Sohal, Rajindar S (2008) Detection and characterization of in vivo nitration and oxidation of tryptophan residues in proteins. Methods Enzymol 441:339-49
Rebrin, Igor; Bregere, Catherine; Gallaher, Timothy K et al. (2008) Detection and characterization of peroxynitrite-induced modifications of tyrosine, tryptophan, and methionine residues by tandem mass spectrometry. Methods Enzymol 441:283-94
Rebrin, Igor; Sohal, Rajindar S (2008) Pro-oxidant shift in glutathione redox state during aging. Adv Drug Deliv Rev 60:1545-52

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