A comparison of dietary fish oil and corn oil in experimental colorectal carcinogenesis.
Rats fed either fish oil (n = 16) or corn oil (n = 16) in calorically and nutritionally balanced diets were injected with 1,2-dimethylhydrazine, which is a colorectal specific carcinogen; differential colorectal tumor induction was then measured. In addition, plasma peroxide concentrations were measured in rats in each dietary group as well as in a group receiving a low-fat diet, either with or without prior carcinogen treatment (n = 3 for each of the 6 groups). Tumor incidence did not differ between groups fed corn oil and fish oil. Tumor yield in the left colon was significantly lower in rats fed fish oil (p = 0.0499). Total colorectal tumors induced were also fewer in the rats fed fish oil (p = 0.065). Plasma peroxide concentrations were difficult to interpret because of the wide variation within groups. The data on tumor yield in the left colon support the hypothesis that a diet rich in n-3 fatty acids, which are found in fish oil, may be less supportive of colorectal tumor development than a diet rich in n-6 fatty acids, which is found in corn oil. However, the mechanism by which fish oil decreases tumor induction is still unknown.
Nelson
R L
RL
Department of Surgery, University of Illinois, Chicago 60612.
Tanure
J C
JC
Andrianopoulos
G
G
Souza
G
G
Lands
W E
WE
D019813:1,2-Dimethylhydrazine; D000818:Animals; D015179:Colorectal Neoplasms / Q000097:blood / Q000139:chemically induced / Q000517:prevention & control*; D003314:Corn Oil / Q000008:administration & dosage*; D004127:Dimethylhydrazines; D005395:Fish Oils / Q000008:administration & dosage*; D008297:Male; D010545:Peroxides / Q000097:blood; D010938:Plant Oils / Q000008:administration & dosage*; D051381:Rats; D011919:Rats, Inbred Strains
D004127:Dimethylhydrazines; D005395:Fish Oils; D010545:Peroxides; D010938:Plant Oils; D003314:Corn Oil; D019813:1,2-Dimethylhydrazine