Journal
FREE RADICAL RESEARCH
Volume 37, Issue 5, Pages 543-553Publisher
TAYLOR & FRANCIS LTD
DOI: 10.1080/1071576031000083206
Keywords
melatonin; enzyme modification; free radicals; AAPH; peroxyl radicals; catalase
Categories
Funding
- NIA NIH HHS [T32AG00165-13] Funding Source: Medline
Ask authors/readers for more resources
Thermal decomposition by the azo initiator 2,2' azobis(2-amidinopropane) dihydrochloride (AAPH) has been widely used as a water-soluble source of free radical initiators capable of inducing lipid peroxidation and protein damage. Here, in a lipid-free system, AAPH alone (40 mM) rapidly induced protein modification and inactivation of the enzyme catalase (EC 1.11.1.6). Using SDS-PAGE, it was shown that protein band intensity is dramatically reduced after 4 h of incubation with AAPH, leading to protein aggregation. Several antioxidants including melatonin, glutathione (GSH) and trolox prevented catalase modification when used at a 250 muM concentration whereas ascorbate was only effective at 1 mM concentration. All the antioxidants tested reduced carbonyl formation although melatonin was the most effective in this regard. Enzyme inactivation caused by AAPH was also significantly reduced by the antioxidants and again melatonin was more efficient than the other antioxidants used in this study. Results shown here demonstrate that alkyl peroxyl radicals inactivate catalase and reduce the effectiveness of cells to defend against free radical damage; the damage to catalase can be prevented by antioxidants, especially melatonin.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available