Background: There is a high risk of mortality from cardiovascular diseases among women with breast cancer. Aerobic exercise training is effective in preventing and survival of these diseases as well as prevention and treatment of breast cancer. This study aimed to investigate the effects of exercise preconditioning on the levels of interleukin 6 (IL-6) and 10 (IL-10) in cardiac tissue in mice with breast cancer.

Materials and methods: The study was conducted on 56 BALB/c mice (female and 3-5 weeks old) with an average weight of 15-20 g which randomly divided into two groups of active and inactive ones. The active group swam for three weeks, three days a week and 30 minutes daily, in a water tank. After three weeks, a million tumor cells were injected into them. Both groups were separately divided into four subgroups: A) continued training group, B) stop exercise group, C) chemotherapy with doxorubicin, and D) exercise –doxorubicin group. Finally, the levels of IL-6 and 10 of cardiac tissue were determined as inflammatory and anti-inflammatory markers.

Results: Findings showed a significant increase of IL-10 in the active group (in subgroups A and B (none-chemotherapy groups) compared to the passive group, while this difference did not exist between two main groups in subgroups C and D (chemotherapy groups). Despite the lack of a significant difference in training-chemotherapy subgroups (D), a greater increase of IL-10 among them than the group of chemotherapy alone was observed. Also, there was a significant reduction of IL-6 in the active group compared to the inactive which was observed in all subgroups.

Conclusion: The results of this study showed that eight weeks of endurance swimming training before cancer may result in reducing inflammatory complications of cancer in mice with breast cancer with increase and decrease in the levels of IL-10 and IL-6 in cardiac tissue, respectively.