semmelweis university - Faculty of Physical Education and Sport ...

Orsolya Marton
Semmelweis University, Faculty of P. E. and Sport Sciences (TF), Budapest, Hungary
Supervisor: Dr. Zsolt Radák, professor
Consultant: Erika Koltai, PhD student
The Effect of Aging and Exercise on Acetylation of Proteins in Cerebellum of Rats: Role
of Sirtuins
Introduction: Aging is an unavoidable process, in which sirtuins are playing important role.
Sirtuins have got seven classes in mammals and are NAD + dependent protein deacetylases.
Moreover, sirtuins suggested regulators of fat and sugar metabolisms, brain function, DNA
repair, mitochondrial biogenesis, inflammation, apoptosis and fiber type differentiation of
skeletal muscle. In the present study the effects of sirtuins on proteins in cerebellum by aging
and mild exercise were tested.
Hypothesis: Our hypothesis is that exercise training prevents the age-associated decrease in
the level and activity of SIRT1 in the cerebellum. Furthermore, we suggested that NAMPT
level also decreasing with aging, since this enzyme plays a crucial role in the biosynthesis of
NAD + . Aging is associated with decreases in protein turnover and increases the half-life of
proteins. We hypothesized that acetylation of lysine residues could curb the ubiquitination,
hence aging increases the level of acetylation, which results in increases in the half life of
proteins.
Methods: Twelwe young (6 mo) and ten old (30 mo) male Wistar rats were selected for the
study and divided into young control (YC), young exercised (YE), old control (OC) and old
exercise (OE) groups. The exercise program was moderate running on treadmill for four
weeks, four time a week with the gradually increasing duration with the starting from 20 min
on the first week and 40 min on the last week. The running intensity was set at 60% of the
VO2 max (ranged between 10-20 m/min). The brain function was evaluated by Morris-maze
test. The strength of forelimb of the animals was assessed by gripping test on pole. The
biochemical analysis was assessed by Western-blot and fluorometric methods. Statistical
significance was assessed by one-way ANOVA, followed by Tukey‘s post hoc test and
correlation. The significance level was set at p