Carbonyl-modified proteins are considered markers of oxidative damage caused by oxidative stress, aging, and disease. Here we use a previously developed capillary electrophoretic method for detecting femtomole (10 -15 mole) carbonyl levels in mitochondrial proteins that are size separated and profiled. For protein labeling, carbonyls were tagged with Alexa 488 hydrazine and amine groups in proteins with 3-(2-furoyl)quinoline-2- carboxaldehyde. Total mitochondrial protein carbonyl levels were statistically higher in fast- than in slow-twitch muscle of young Fischer 344 rats, and statistically higher in old than in young slow-twitch muscle. Even when some statistical comparisons of the total protein carbonyl levels would not reveal differences, principal component analysis (PCA) classified the carbonyl profiles into four distinct sample groups of different age and muscle types. In addition, PCA was used to predict that most age- related or muscle-type-related changes in carbonyl levels occur in proteins with a molecular weight between 9.8 and 11.7 kD.
|Original language||English (US)|
|Number of pages||12|
|Journal||Journals of Gerontology - Series A Biological Sciences and Medical Sciences|
|State||Published - Dec 2008|
Bibliographical noteFunding Information:
ACKNOWLEDGMENTS This work was supported by the National Institutes of Health (AG025371). E.A.A. acknowledges the support of the NIH by a Career Award (1K02-AG21453).
- Capillary electrophoresis
- principal component analysis