Age-related changes in activity of catalase in selected bovine muscles

ABSTRACT

Background: The unavoidable consequence of ageing process is oxidative stress which is harmful to cells. Muscles asa post-mitotic cells are especially susceptible for it. They are protected by antioxidants. One of the main antioxidantenzymes is catalase (CAT). Although muscles were extensively examined for antioxidant defense, there is a lack of comparative study regarding CAT activity in skeletal muscles, heart muscle and diaphragm in cows. The aim of present studywas investigate the link between age related alterations and antioxidant defense system and confirmation that CAT activitydepends on age and type of muscle tissue dependent on metabolic rate.Materials, Methods & Results: Samples of skeletal muscles, heart and diaphragm were collected from healthy HolsteinFriesian cows aged between 14 and 27 months (n = 12; sexually mature) and female calves aged between 2 weeks and 2months (n = 9; sexually immature) in slaughterhouse. The enzyme activity was measured by spectrophotometric method.Additionally the presence of CAT was confirmed by SDS-PAGE separation and detected by zymography. In current investigation CAT activity in heart and diaphragm showed significantly higher (P < 0.05) values than in skeletal muscles.Moreover, CAT activity was higher in cows than in calves in heart (0.28 ± 0.044 U /mg protein vs. 0.4 ± 0.035) as well asin diaphragm (0.27 ± 0.047 vs 0.37 ± 0.077), however in skeleton muscles there were no significant differences betweenexamined animals (0.076 ± 0.016 vs 0.084 ± 0.0197). According to received results CAT activity increased during agingin heart and diaphragm while in skeleton muscles age-related changes were not observed.Discussion: Skeletal muscles are particularly vulnerable to oxidative stress because...