Effect of 8 weeks high-intensity interval training (HIIT) with and without caloric restriction on gene expression of myocardial Bax and Bcl2 in mice

Apoptosis is the physiological cell death that in natural conditions leads to the elimination of old, damaged, waste, and harmful cells. The aim of this study was the effect of eight weeks of high-intensity interval training (HIIT) with and without caloric restriction on gene expression of myocardial Bax and Bcl2 in mice.

Present study was an experimental multi-group design with a control group conducted on 30 two-month old male mice. Subjects were divided into five homogenous groups including base control, control, caloric restriction, interval exercise training, and caloric restriction + interval exercise training. Training groups participated in interval exercise training five sessions per week for 8 weeks. The level of gene expression of myocardial Bax and Bcl2 was evaluated by real-time PCR. Data were analyzed using the one-way ANOVA at the level of (P<0.05).

The results showed that the training group had a significant increase in gene expression of myocardial Bcl2 in comparison with caloric restriction + exercise training (P<0.05) and a significant decrease in gene expression of myocardial Bax compared to the caloric restriction group (P<0.05). Also, exercise training and exercise training + caloric restriction significantly increased the gene expression of myocardial Bcl2 and significantly decreased Bax/Bcl2 ratio compared to caloric restriction, base control, and control (P< 0.05).

It seems that high-intensity interval training without caloric restriction would provide a suitable environment for increasing the integrity of the mitochondrial membrane of myocardial cells and possibly apoptosis.