Assessment of stress and anxiety in mice with colorectal cancer submitted to physical exercise

Purpose:  To evaluate the effect of physical exercise on the behavior of rodents with colorectal cancer induced through the use of elevated plus maze.

Methods:  We used 40 male hairless mice induced to colorectal cancer, divided into five groups: G1) submitted to pre- and post-induction swimming; G2) pre- and post-induction ladder; G3) post-induction swimming; G4) post-induction ladder; G5) sedentary. At the end of the 14th week, the animals were submitted to the plus maze test.

Results:  The mean length of stay in the open arm for G1 was 4.17 ± 6.50; G2 37.52 ± 40.7; G3 85.84 ± 42.5; G4 32.92 ± 23.17; and G5 4.09 ± 4.43. In the closed arm, it was 264 ± 23.43 in G1, 187.60 ± 47.73 in G2, 147.50 ± 40.03 in G3, 182.00 ± 40.40 in G4, and in G5 235.36 ± 14.28. In the center, G1 remained 31.86 ± 20.18, G2 74.85 ± 28.37, G3 66.69 ± 19.53, G4 60.55 ± 10.46, and G5 60.55 ± 23.65.

Conclusions:  Aerobic exercise for seven weeks after tumor induction showed less impact on the behavior of the animals. On the other hand, it significantly increased the animals’ stress level when applied for 14 weeks before and after tumor induction.

Key words
Models, Animal; Colitis-Associated Neoplasms; Elevated Plus Maze Test; Exercise