Long-term aerobic swimming training by rats reduces the number of aberrant crypt foci in 1,2-dimethylhydrazine-induced colon cancer

Abstract

We determined the effect of long-term aerobic swimming training regimens of different intensities on colonic carcinogenesis in rats. Male Wistar rats (11 weeks old) were given 4 subcutaneous injections (40 mg/kg body weight each) of 1,2-dimethylhydrazine (DMH, dissolved in 0.9% NaCl containing 1.5% EDTA, pH 6.5), at 3-day intervals and divided into three exercise groups that swam with 0% body weight (EG1, N = 11), 2% body weight (EG2, N = 11), and 4% body weight of load (EG3, N = 10), 20 min/day, 5 days/week for 35 weeks, and one sedentary control group (CG, N = 10). At sacrifice, the colon was removed and counted for tumors and aberrant crypt foci. Tumor size was measured and intra-abdominal fat was weighed. The mean number of aberrant crypt foci was reduced only for EG2 compared to CG (26.21 ± 2.99 vs 36.40 ± 1.53 crypts; P < 0.05).

Fish oil ingestion reduces the number of aberrant crypt foci and adenoma in 1,2-dimethylhydrazine-induced colon cancer in rats

“…Aberrant crypt foci (ACF) are considered to be putative preneoplastic colon lesions that may be early indicators of colon carcinogenesis (3,4). ACF and tumors can be chemically induced by administering chemical carcinogens to experimental animals, among them, 1,2-dimethylhydrazine (DMH) or azoxymethane (5,6). DMH is one of the agents most frequently used in experimental models of colon carcinogenesis in rodents (6,7).…”

“…ACF and tumors can be chemically induced by administering chemical carcinogens to experimental animals, among them, 1,2-dimethylhydrazine (DMH) or azoxymethane (5,6). DMH is one of the agents most frequently used in experimental models of colon carcinogenesis in rodents (6,7).…”

Effects of a probiotic in combination with prebiotics on intestinal lactobacilli and coliforms and activities of bacterial enzymes in 1,2-dimethylhydrazine exposed rats

“…Some studies showed that a high fat diet increased the risk of colon cancer (Meyerhardt et al, 2007). 1,2-DMH is a common colon carcinogen often used in developing CRC in various experimental animals (Fukui et al, 2001;Lunz et al, 2008).…”

Colon cancer and swimming exercise: effect on wistar rat testes

“…Colon cancer was induced by the application of four subcutaneous injections of 1,2-dimethylhydrazine (DMH, Sigma, USA) as previously described by Lunz et al (2008). Two injections were given in the first week and the others in the second week on nonconsecutive days.…”

“…Several risk factors are associated with the development of colon cancer, which include the family history of colon cancer, smoking, excessive alcohol ingestion and sedentarism (Friedenreich and Orenstein 2002;Harriss et al 2009). Many studies have shown the influence of physical exercise on the decrease of colon cancer incidence (Friedenreich and Orenstein 2002;Demarzo et al 2008;Lunz et al 2008). Demarzo et al (2008) showed that moderate chronic swimming exercise was antiproliferative and antinflammatory for the rat colon cells.…”