Effects of high intensity interval training and aging on cardiac muscle apoptosis markers in C57BL/6 Mice

Background Apoptosis is a specific form of programmed cell death that plays an important role in tissue homeostasis and also occurs during aging. In addition, exercise training may alter apoptosis-related signaling in muscles, including the cardiac muscle. However, the effects of high-intensity interval training (HIIT) on apoptosis markers in the heart have not yet been studied . Thus, the aim of the present study was to investigate the effects of HIIT on Bcl-2 and Bax expression protein levels in young and old cardiac muscles. Methods Four and 24-month old C57BL/6J mice were used as our young adult and old groups, respectively. Animals were randomly assigned to four groups: young control (YC), young trained (YT), old control (OC), and old trained (OT). The trained groups performed HIIT 5 sessions per week for 4 weeks. RNA extraction and synthesis of cDNA was performed, and Bax and Bcl2 heart gene levels were determined by RT-PCR analysis. Results Training induced significant increases in Bcl-2 gene expression in YT group comparing to the YC group ( p = 0.010) and in OT group comparing to OC group ( p = 0.002). Training induced non-significant decrease ( p > 0.05) in Bax gene expression and in Bax/Bcl-2 ratio in YT group comparing to the YC group and in OT group comparing to OC group. Aging showed no significant effect in Bcl-2 gene expression, Bax gene expression, and Bax/Bcl-2 ratio in CY group comparing to the OC group and in YT group comparing to OT group ( p > 0.05). Conclusion In conclusion, 4 weeks of HIIT increased Bcl-2 level for young and old heart muscles, and no effect of aging was revealed, indicating that HIIT ameliorated anti-apoptotic signaling in the young and old heart of mice.