EFFECT OF THE SPIN-TRAPPING COMPOUND N-TERT-BUTYL-ALPHA-PHENYLNITRONEON PROTEIN OXIDATION AND LIFE-SPAN

N-tert-Butyl-alpha-phenylnitrone (PBN), a lipophilic spin-trapping com pound, has been reported to decrease the concentration of protein carb onyls, the products of protein oxidation, in the brain of old gerbils to virtually the level found in the young gerbils (Carney, J. M., ct a l. (1991) Proc. Natl. Acad. Sci. USA 88, 3633-3636), The validity of t his finding as well as that of the commonly used 2,4-dinitrophenylhydr azine procedure for the measurement of protein carbonyls was recently called into question by Cao and Cutler ((1995) Arch. Biochem. Biophys. 320, 106-114), The objective of the present study was to examine some of the relevant issues such as (a) whether the original findings on t he effects of PEN can be confirmed, (b) whether similar effects of PEN occur in other species and tissues, and (c) whether PEN affects the l ife span of animals. Results of this study provide confirmation of the original finding that PEN indeed causes a decrease in protein carbony l content in the gerbil brain cortex. However, a similar effect is not observed in the gerbil heart or the mouse brain cortex. Effects of PE N on protein carbonyls are thus variable depending upon tissue and spe cies. PEN administration did not extend the life span of houseflies an d at relatively high concentrations it was found to be toxic. (C) 1995 Academic Press, Inc.