The increase of adipose tissue changes the inflammatory status. Several studies suggest that low level of chronic inflammation increase the risk of cancer development. Scientific evidences suggest
that the moderate physical exercise can be used to modulate the control of inflammation. Therefore, we want to analyze how the moderate physical exercise can modulate macrophage profile in the tumor
microenviroment in C57BL-6 mice with melanoma and submitted to high-fat diet.
22 female mice C57BL-6 were divided in four groups: Normolipidic Diet Melanoma (NM) High-fat Melanoma (HM), Normolipidic Exercise Melanoma (NEM) and High-fat Exercise Melanoma (HEM). All mice were
treated during eight weeks with normolipidic diet (4%fat) or high-fat diet (40%fat) and the exercise groups trained 5 days per week, 60 minutes per day between 50 to 65% maximal velocity in treadmill.
After, the animals received 1x106 B16F10 cells and were accompanied by two weeks. We analyze the tumor growth, percentage of cells macrophages , Treg and Th17 cells in tumor microenviroment using flow
cytometry. Differences between groups were detected by Anova Two Way, and Bonferroni post hoc test (p<0,05) performed by Graph Pad Prism 5.0.
The physical exercise improved maximal velocity in treadmill in NEM and HEM groups compared to baseline (NEM increased 9,0 ± 2,0 m/min and HEM 3,0 ± 1,9 m/min, respectively). On the other hand,
control group decreased performance (NM decresed 1,28 ± 2,23 m/min and HM 4,50 ± 2,49 m/min). Mice submitted to high-fat diets developed higher body weight gain (HM 8,22 ± 1,05 g, and HEM 8,63 ± 1,48
g higher when compared to the respective normolipidic group. The tumor weight was higher in high-fat groups (HM 1,29 ± 0,46 g, and HEM 1,04 ± 0,44 g higher values) when compared with their
respective normolipidic groups. We -observed that M1macrophage percentage was higher in HM than in the others groups (HM 24,8 ± 4,13% and 25,35 ± 4,46% more cells than NM and HEM groups,
respectively). It was not observed differences in M2, Treg and Th17 cells.
In conclusion these results show that moderate physical exercise can decrease inflammatory response associated with M1 macrophages in tumor microenviroment leading to a lower tumor growth in obese