Age-related modifications of egr1 expression and ubiquitin-proteasome components in pet dog hippocampus.
In this paper we examined the impact of age on cognitive functions and the age-related modifications of egr1 expression, an inducible transcription factor with a confirmed role in synaptic plasticity and regulation of the proteasome activity, on pet dogs. Additionally, we examined the age-related changes of some elements of the ubiquitin-proteasome system, which is the apparatus that prevents the intracellular accumulation of abnormal proteins. The results of behavioral analysis revealed that old/senior dogs (9-16-year-old) had impaired cognitive performance compared to young/middle-aged dogs (2-8-year-old) in the Reversal Learning task. Taken togheter, the results (age-related decline of Psmd4, Psmb8, CHIP, and egr1 expression; increase of Psmb9 and Hsp90 expression) suggest that the activity of the ubiquitin-proteasome system in the dog hippocampus is a multi-step process, in which abnormal proteins destined for degradation are recognized and destroyed, and shows an age-related decline. The consequent failure of the "protein quality control system" might have detrimental effects on cell physiology and lead to a progressive impairment of cognitive functions.
Dipartimento di Anatomia, Farmacologia e Medicina Legale, Università degli Studi di Torino, C.so Raffaello 33, 10125 Torino, Italy. piera.ghi@unito.it
Piera
P
Ghi
Fabio
F
Di Brisco
Dario
D
Dallorto
Maria Cristina
MC
Osella
Marco
M
Orsetti
D000367:Age Factors; D000818:Animals; D001522:Behavior, Animal; D002415:Cats; D003071:Cognition; D051766:Early Growth Response Protein 1 / Q000096:biosynthesis*; D005260:Female; D018841:HSP90 Heat-Shock Proteins / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism*; D008297:Male; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D025801:Ubiquitin / Q000378:metabolism*
D051766:Early Growth Response Protein 1; D018841:HSP90 Heat-Shock Proteins; D025801:Ubiquitin; D046988:Proteasome Endopeptidase Complex