Testing mitochondrial metabolic competence by cytochrome oxidase preferential cytochemistry versus immunoreactivity of subunits I and IV.
Cytochemically evidenced COX activity was compared with levels of immunohistochemically stained mitochondrial- and nuclear-encoded subunits (CO I and CO IV) in the dentate gyrus outer molecular layer (OML) and cerebellar granular layer (GL) of adult and old rats. COX activity decreased significantly in aging, whereas CO I and CO IV levels were significantly increased both in GL and OML of old animals. These findings suggest that the age-related decay of the mitochondrial metabolic competence is not caused by a reduction of COX subunits levels, but causal events affecting mitochondria as discrete morphofunctional units of the cellular bioenergetic machinery.
Fattoretti
Patrizia
P
Neurobiology of Aging Laboratory, INRCA Research Department, Ancona, Italy. p.fattoretti@inrca.it
Balietti
Marta
M
Giorgetti
Belinda
B
Grossi
Yessica
Y
Casoli
Tiziana
T
Di Stefano
Giuseppina
G
Bertoni-Freddari
Carlo
C
D000375:Aging / Q000502:physiology*; D000818:Animals; D002467:Cell Nucleus; D002531:Cerebellum / Q000201:enzymology; D003576:Electron Transport Complex IV / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D006624:Hippocampus / Q000201:enzymology; D006651:Histocytochemistry; D008928:Mitochondria / Q000201:enzymology* / Q000235:genetics; D009474:Neurons / Q000201:enzymology*; D051381:Rats; D017208:Rats, Wistar
D003576:Electron Transport Complex IV