Effects of different frequencies of physical training on electron transport chain and oxidative damage in healthy mice

Luciano A Silva,Paulo Cesar Loock Silveira,Ramiro Doyenart,Camila B Tromm,Ricardo Aurinho Pinho,Anand Thirupathi

doi:10.1590/s1980-6574201800040008

Abstract

Abstract Aims: The present study investigated the effect of different frequencies (three and five times a week) on electron transport chain and oxidative stress after 8 weeks of run training. Methods: Eighteen male mice (CF1, 30-35g) were distributed into the following groups (n=6): untrained (UT); trained three-time per week (T3) and trained five- time per week (T5). All training sessions were at the same intensity and duration (45min/day) in a treadmill for small animals. Forty-eight hours after the last training session, the animals were killed by decapitation and quadriceps (red portion) was removed and stored at -70oC. Succinate dehydrogenase (SDH), complexes I, II, II-III, IV and hydroperoxides were measured. Results: Training sessions for five times per week were more effective in increasing the mitochondrial respiratory chain enzyme activities (SDH, complexes I, II, II-III, IV) as well as in decreasing the formation hydroperoxides than sessions performed for three times training per week (p<0.05). Conclusion: Our findings clearly showed that a higher the frequency of training session promotes a greater activity of the electron transport chain and consequently reduces the oxidative stress in healthy animals.

Highlights

Mitochondrial oxygen flux enhances the ATP production in the skeletal muscle during physical exercise.[1,2,3] It is well known that muscle adaptation to regular exercise involves mitochondrial biogenesis and regulate respiratory chain activities to compensate for energy demands.[4]The beneficial effects of regular moderate exercise have been consistently reported in human and animal studies
Succinate Dehydrogenase (SDH): Figure 1 shows a significant increase in SDH in both trained groups (T3: 69.6 ± 6 and T5: 116.4± 16 nmol/min/mg protein) when compared with UT group (27.3±4.6 nmol/min/mg protein) that was dependent of the training frequency.(p
Mitochondrial respiratory chain enzyme activities: Regarding Complex I, our findings show an increase in the NADH dehydrogenase activities in both trained groups (T3: 255 ± 19 and T5: 444±55 nmol/min/mg protein) when compared with UT group (104± 19 nmol/min/mg protein)

Summary

Introduction

Mitochondrial oxygen flux enhances the ATP production in the skeletal muscle during physical exercise.[1,2,3] It is well known that muscle adaptation to regular exercise involves mitochondrial biogenesis and regulate respiratory chain activities to compensate for energy demands.[4]. Several studies have been carried out in the skeletal muscles of rats to determine the influence of exercise on the mitochondrial enzyme adaptation.[2,3,5,6]. Regular moderate exercise exhibited a beneficial effect in preventing the age-associated decline by a maintenance of the activities of mitochondrial complexes IV and I.7. It is important to develop a research to detecting if a different frequency of exercise sessions would reduce the oxidative damages due to electron transport chain. No studies examined the effects of different frequencies (threeor five- time a week) on electron transport chain and oxidative stress. The present study investigated the effect of different frequencies of run training (three or five times a week) on electron transport chain activity and oxidative damages in healthy mice. We hypothesized that physical training induces changes in muscle oxidative metabolism in a frequency-dependent manner in rats

Materials and Methods

Results

Discussion