Investigating the effect of exercise training in different periods of growth on protein synthesis (4E-BP1) and proliferation of cardiac cells (S6K1) in male rats

Document Type : Original Article


1 Professor of Exercise Physiology, University Of Guilan, Rasht, Iran

2 PhD Student of Exercise Physiology, University Of Guilan, Rasht, Iran

3 Assistant Professor, Department of Physical Education, Faculty of Humanities, Islamic Azad University, Rasht Branch, Rasht, Iran.


We investigate the effect of exercise training in different stages of growth on protein synthesis (4E-BP1) and proliferation of heart cells (S6K1) in male rats. 30 male Wistar rats were prepared in three age groups of 2 weeks, 8 weeks, and 90 weeks (10 in each group), and each age group was divided into two control and training groups (5 in each group). In the exercise training group, the animals performed the resistance and aerobic training program every day (interval). The amount of overload for the resistance-training program was determined based on the body weight of the animals. For the aerobic training group, the training intensity increased from 50% of maximum speed in the first week to 80% in the last week. The results showed that there is no significant difference between the control and training groups in each age, as well as between the training groups in the three age (p>0.05). In contrast, the 2-week exercise groups (p=0.022) showed a significant increase and the 90 weeks control group (p=0.002) showed a significant decrease in S6K1 protein in cardiac tissue compared to the 2-week control groups. In the analysis of gene expression, it was also found that the 2-week training group showed a significant increase in S6K1 gene expression compared to the 2-week control group (p=0.018). It seems that doing combined exercise at different ages, especially childhood, has a greater effect on the proliferation index of heart cells (S6K1). However, studies with longer training durations should also be considered.

What is already known on this subject?

At early stages of life, cardiac myocytes exit the cell cycle in the perinatal period. Subsequent maturation or adaptive (hypertrophic) growth in the heart results from an increase in cell size. Cardiac hypertrophy is also affected by exercise training.


What this study adds?

combined exercise at different ages, especially early stage of life has a greater effect on the proliferation of heart cells (S6K1).


Main Subjects





Compliance with ethical standards

Conflict of interest The authors declare that they have no conflict of interest.

Ethical approval Animals had free access to standard food and water. All stages of keeping and slaughtering rats were carried out according to the rules of the Animal Ethics Committee of Islamic Azad University, Rasht Branch (ethical code: IR.IAU.RASHT.REC.1399.024).

Informed consent Animal study.

Author contributions

Conceptualization: B.M., H.G.A.; Methodology: MR.FC.; Software: B>M.; Validation: H.G.A.; Formal analysis: MR.FC.; Investigation: .B.M.; Resources: H.G.A.; Data curation: H.G.A., B.M.; Writing - original draft: MR.FC.; Writing – review & editing: B.M.; Visualization: B.M., H.G.A.; Supervision: MR.FC.; Project administration: B.M., H.G.A.; Funding acquisition: MR.FC. 

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