Incorporation of dietary trans monounsaturated fatty acids into tissues of Walker 256 tumor-bearing rats.
The correlation between dietary trans fatty acids and neoplasia was examined in the present study. Walker 256 tumor-bearing and control rats were fed a trans monounsaturated fatty acid (MUFA)-rich diet for 8 weeks and the incorporation of trans fatty acids by tumor tissue was examined. Also, the effect of tumor growth on trans fatty acid composition of plasma and liver, and the content of thiobarbituric acid-reactive substances (TBARS) was determined. Walker 256 tumor cells presented both trans and cis MUFAs given in the diet. The equivalent diet proportions were 0.66 for trans and 1.14 for cis. Taking into consideration the proportion of trans MUFAs in plasma (11.47%), the tumor incorporated these fatty acids in a more efficient manner (18.27%) than the liver (9.34%). Therefore, the dietary trans fatty acids present in the diet are actively incorporated by the tumor. Tumor growth itself caused marked changes in the proportion of polyunsaturated fatty acids in the plasma and liver but provoked only slight modifications in both trans and cis MUFAs. Tumor growth also reduced the unsaturation index in both plasma and liver, from 97.79 to 86.83 and from 77.51 to 69.64, respectively. This effect was partially related to an increase in the occurrence of the lipid oxidation/peroxidation process of TBARS content which was increased in both plasma (from 0.428 to 0.505) and liver (from 9.425 to 127.792) due to tumor growth.
Moreira
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Departamento de Alimentos e Nutrição Experimental, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, Av. Professor Lineu Prestes, 580, 05508-900 São Paulo, SP, Brazil.
Curi
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Padovese
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Mancini-Filho
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D000818:Animals; D002279:Carcinoma 256, Walker / Q000378:metabolism*; D004041:Dietary Fats / Q000009:adverse effects; D004042:Dietary Fats, Unsaturated / Q000378:metabolism*; D005227:Fatty Acids / Q000032:analysis / Q000097:blood / Q000378:metabolism; D005229:Fatty Acids, Monounsaturated / Q000032:analysis / Q000097:blood / Q000378:metabolism*; D015227:Lipid Peroxidation; D008099:Liver / Q000737:chemistry; D008297:Male; D008325:Mammary Neoplasms, Experimental / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
D004041:Dietary Fats; D004042:Dietary Fats, Unsaturated; D005227:Fatty Acids; D005229:Fatty Acids, Monounsaturated