Effects of selenium supplementation on the muscle contractile properties, fatigue and antioxidant enzymes activities of gastrocnemius muscles in trained and untrained rats

Abstract

Selenium (Se) is an important component of cellular seleno

â€Âcompounds and

an integral component of glutathione Peroxidase (GPx), which catalyzes the

reduction of harmful radicals produced during muscular exercise. The current

study was carried out to evaluate the muscle contractile properties and

fatigue resistance of gastrocnemius muscle under selenium supplementation

schemes in sedentary and exercise protocols as well as measure the antioxidant

enzymes activity and lipid peroxidation. Rats were divided into four

groups; sedentary Selenium supplementation (S), exercise Selenium (SE)

groups, sedentary control (SC) and exercise control (EC) groups. The rats

were fed with 80 μg/kg body weights selenium for six weeks. The exercise

protocol consisted the 40 jumps up to the height of 40 cm for 6

â€Âweek. The

muscle fatigue protocol consisted the trains of pulses of 40 Hz at every second

for at least 2 min. Significant (P<0.05) increase was observed in treated

groups than control in the muscle contractile properties like twitch tension

(Pt), contraction time (CT) and twitch/tetanic tension Ratio (Pt/Po Ratio),

tetanic tension (Po) and EMG amplitude. Decreased EMG failure and increased

fatigue index were observed in ES group. Moreover, a significant

(P<0.05) increase and decrease in the GPx activity and lipid peroxidation respectively

was also reported than SC and EC group. While there were no

changes reported in the activity of CAT and SOD enzymes. This study revealed

that the Se with jumping exercise induces muscle contractile properties

and decreases the muscular fatigue.