High fat mixed lipid diet modifies protective effects of exercise on 1,2 dimethylhydrazine induced colon cancer in...

The aim of the present study was to evaluate the effect of long-term swimming exercise in conjunction with a high fat mixed lipid (HFML) diet on colon cancer (CC) development and lipid peroxidation in the large bowel. We used forty male Wistar rats, which were randomly divided into one control group and four cancer groups: sedentary and swimming groups fed a standard diet (LFCO) and sedentary and swimming groups fed an HFML diet. Corticosterone was determined during the experiment. After 6 months of swimming, the rats were sacrificed and blood, heart, liver, muscle and large bowel were taken for determining the activity of serum enzymes, antioxidant capacity and CC development. The results demonstrate that exercise has a protective role in CC development. Attenuated development of CC and increased levels of malondialdehyde (MDA) in the large bowel of exercised rats show that one of the protective effects of exercise on developing CC is induction of oxidative stress. However, in terms of the combined effects of dietary fat and exercise, our results indicate that the protective role of exercise on CC development is significantly depressed by an HFML diet. An HFML diet significantly reduced the protective influence of exercise on colon carcinogenesis in rats and affected the degree of peroxidation in the large bowel during exercise, as well as concentrations of serum enzymes (LDH, α-HBDH, CK, ALT and AST). Our results indicate that an HFML diet, which reflects the composition of a Western style diet, is a significant modifier of the protective effects of exercise on CC development in rats.