Accumulation of overoxidized Peroxiredoxin III in aged rat liver mitochondria.
Overoxidation and subsequent inactivation of Peroxiredoxin III (PrxIII), a mitochondrial H(2)O(2) scavenging enzyme, have been reported in oxidative stress conditions. No data are available in the literature about the presence of overoxidized forms of PrxIII in aged tissues. Liver mitochondria from 12-month-old rats and 28-month-old rats were here analyzed by two-dimensional gel electrophoresis. A spot corresponding to the native form of PrxIII was present in adult and old rats with the same volume, whereas an additional, more acidic spot, of the same molecular weight of the native form, accumulated only in old rats. The acidic spot was identified, by MALDI-MS analysis, as a form of PrxIII bearing the cysteine of the catalytic site overoxidized to sulphonic acid. This modified PrxIII form corresponds to the irreversibly inactivated enzyme, here reported, for the first time, in aging. Three groups of 28-month-old rats treated with acetyl-l-carnitine were also examined. Reduced accumulation of the overoxidized PrxIII form was found in all ALCAR-treated groups.
Musicco
Clara
C
Institute of Biomembranes and Bioenergetics, Consiglio Nazionale delle Ricerche (CNR), Bari, Italy.
Capelli
Valentina
V
Pesce
Vito
V
Timperio
Anna Maria
AM
Calvani
Menotti
M
Mosconi
Luigi
L
Zolla
Lello
L
Cantatore
Palmiro
P
Gadaleta
Maria Nicola
MN
D000108:Acetylcarnitine / Q000494:pharmacology; D000375:Aging; D000818:Animals; D003545:Cysteine / Q000737:chemistry / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D008297:Male; D013058:Mass Spectrometry; D008930:Mitochondria, Liver / Q000378:metabolism*; D008970:Molecular Weight; D018697:Nootropic Agents / Q000494:pharmacology; D010084:Oxidation-Reduction; D054464:Peroxiredoxins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D011916:Rats, Inbred F344; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D018697:Nootropic Agents; D000108:Acetylcarnitine; D054464:Peroxiredoxins; D003545:Cysteine