Effect of dietary conjugated linoleic acid on the in vivo growth of rat hepatoma dRLh-84.
We examined the effect of dietary conjugated linoleic acid (CLA) on the growth of injected hepatoma dRLh-84 in Donryu rats. After experimental diets containing 0% or 2% CLA were given to male Donryu rats for 3 wk, dRLh-84 cells were injected into the left lobe of the hepatic capsule, and the experimental diet was continued. The cells formed a solid tumor > or = 1 wk after the injection, and thereafter the tumor grew with feeding duration. In a morphological study, this tumor appeared to be a low-differentiated hepatoma, and there was no remarkable difference in the morphology of the tumor between 0% and 2% CLA groups. Tumor weight was significantly higher in the 2% CLA group than in the 0% CLA group throughout the feeding period after the injection. Serum glutamic-oxaloacetic transaminase and glutamic-pyruvic transaminase activities were significantly higher in 2% CLA-injected rats than in 0% CLA-injected rats at 3 wk after the injection. CLA upregulated acyl-CoA oxidase activity, especially 1 wk after the injection. However, dietary CLA did not activate carnitine palmitoyl transferase II, which is a rate-limiting enzyme in the mitochondrial beta-oxidation pathway. Natural killer cell activity in the spleen tended to be higher in injected rats, but a significant effect of dietary CLA was not recognized. Serum interferon-gamma and tumor necrosis factor-alpha levels were higher in injected than in sham rats. Moreover, these levels were higher in 2% CLA groups than in the respective 0% CLA groups.
Yamasaki
M
M
Laboratory of Food Chemistry, Division of Applied Biological Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan.
Ikeda
A
A
Hirao
A
A
Tanaka
Y
Y
Miyazaki
Y
Y
Rikimaru
T
T
Shimada
M
M
Sugimachi
K
K
Tachibana
H
H
Yamada
K
K
D000273:Adipose Tissue / Q000473:pathology; D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D001219:Aspartate Aminotransferases / Q000097:blood; D002455:Cell Division; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage*; D007371:Interferon-gamma / Q000097:blood; D007694:Killer Cells, Natural / Q000276:immunology; D019787:Linoleic Acid / Q000008:administration & dosage*; D008099:Liver / Q000378:metabolism; D008114:Liver Neoplasms, Experimental / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D008297:Male; D009929:Organ Size; D010084:Oxidation-Reduction; D051381:Rats; D012450:Safflower Oil / Q000008:administration & dosage; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
D004042:Dietary Fats, Unsaturated; D014409:Tumor Necrosis Factor-alpha; D012450:Safflower Oil; D007371:Interferon-gamma; D019787:Linoleic Acid; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase