XXII. BIOCHEMICKÝ ZJAZD - Jesseniova lekárska fakulta

Posters
93.
AGE-RELATED CHANGES IN ACTIVITIES OF MITOCHONDRIAL ELECTRON
TraNSPORT CHAIN COMPLEXES IN THE raT HEarT.
Stanislav Kuka, Zuzana Tatarková, Peter Račay, Ján Lehotský,
Dušan Dobrota and Peter Kaplán
Department of Medical Biochemistry Jessenius Faculty of Medicine,
Comenius University, Martin
Oxidative damage of tissues by reactive oxygen species (ROS) has been implicated to be
a major factor of aging process. Mitochondria are considered to be the main intracellular
sources of ROS as well as the major target for their damaging effects.
In our study we examined age-related changes in activities of electron transport chain
complexes in cardiac mitochondria of adult (6 months), old (15 months) and senescent
(26 months) male Wistar rats. Our results display non-uniform changes in activities of
particular ETC complexes. While old rats showed no significant changes in activities of
complexes I and II compared with adult control rats, in senescent rats the activities of
both complexes were significantly decreased (P < 0.01). On the other hand, complex III
activity was significantly lower already at 15 months (P < 0.05) and further decreased at
age of 26 months (P < 0.01). The most pronounced age-related changes were observed
in complex IV activity. Compared to adult, complex IV activity decreased by 21% (P <
0.01) at old age and by 37% (P