Transplacental effects of a 15% olive-oil diet on chemically-induced tumorigenesis in offspring.
We evaluated whether feeding pregnant female rats a diet high in olive-oil, that showed a tumor-preventive effect in adults, has a similar preventive effect on chemically-induced cancer in offspring (i.e. mammary glands and colon cancer in rats). The control group was fed the same 7% corn-oil diet as their mothers. Experimental group I was fed a 7% corn-oil diet while their mothers received a 15% olive-oil diet. Experimental group II was fed the same 15% olive-oil diet as their mothers. Female offspring were twice administered 7,12-dimethylbenz(a)antracene (DMBA) in doses of 10 mg/rat. Male offspring were injected 6 times with 1, 2-dimethylhydrazine (DMH) in doses of 20 mg/kg body weight. Effect of DMBA was manifested in a high rate of tumorigenesis: the number of tumor-bearing rats in control offspring reached 52.0%. This effect increased to 60.6% among offspring of experimental group II and to 67.7% in offspring of experimental group I. The mean tumor size increased significantly in control offspring. Following administration of DMH number of tumor-bearing rats was similar in all groups of offspring: 36.7%, 40.7% and 42.8%. Tumor types differed: the majority of tumors in the control group were benign polyps and adenomas (72.1%) and the number of adenocarcinomas was low (27.9%). The number of malignant tumors increased to 37.5% in offspring of experimental group II and to 45.5% in offspring of experimental group I. In control group offspring, a distinct tendency to increased body weight and a significant increase in spleen weight were seen. The findings indicate that feeding mothers a diet high in fat concentrations, even those with known tumor preventive significance in adults, lose this cancer-inhibiting role in offspring.
Kossoy
G
G
Koret School of Veterinary Medicine, Hebrew University of Jerusalem, Rehovot, Israel.
Yarden
G
G
Benhur
H
H
Sandler
B
B
Zusman
I I
II
Stark
A
A
Madar
Z
Z
D019813:1,2-Dimethylhydrazine; D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D016588:Anticarcinogenic Agents / Q000008:administration & dosage*; D002273:Carcinogens; D003110:Colonic Neoplasms / Q000139:chemically induced / Q000178:diet therapy / Q000517:prevention & control*; D004032:Diet; D005260:Female; D008297:Male; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced / Q000178:diet therapy / Q000517:prevention & control*; D008431:Maternal-Fetal Exchange / Q000502:physiology*; D000069463:Olive Oil; D010938:Plant Oils / Q000008:administration & dosage*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D051381:Rats; D017207:Rats, Sprague-Dawley
D016588:Anticarcinogenic Agents; D002273:Carcinogens; D000069463:Olive Oil; D010938:Plant Oils; D015127:9,10-Dimethyl-1,2-benzanthracene; D019813:1,2-Dimethylhydrazine