Docosahexaenoic acid is neither synthesized nor retroconverted by the normal and tumor mouse mammary epithelial cells in primary culture.
Metabolism of 1-14C-[18:3(n-3)] and 1-14C-[22:6(n-3)] were investigated in the primary cultures of normal and tumor mouse mammary epithelial cells. Analysis of endogenous fatty acid composition indicated a decreased proportion of total (n-6) PUFA in the cultured tumor cells compared to normal cells. These cells can synthesize significant amount of 20:5 (n-3) and 22:5 (n-3) but not 22:6 (n-3), from 18:3 (n-3). There was very little or no retroconversion of 22:6 (n-3) by these cells. It has been concluded that mammary epithelial cells may be deficient in 4-desaturase activity and also that exogenous 22:6 (n-3), instead of serving as a source of 20:5 (n-3), may actually counter the effects of both 20:4 (n-6) and 20:5 (n-3) in the mammary tissue.
Bandyopadhyay
G K
GK
Cancer Research Laboratory, University of California, Berkeley 94720.
Mckenzie
K E
KE
Imagawa
W
W
Nandi
S
S
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004041:Dietary Fats / Q000378:metabolism; D004281:Docosahexaenoic Acids / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism; D044943:Fatty Acid Desaturases / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000378:metabolism; D008321:Mammary Glands, Animal / Q000378:metabolism*; D008325:Mammary Neoplasms, Experimental / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D004041:Dietary Fats; D005231:Fatty Acids, Unsaturated; D004281:Docosahexaenoic Acids; D044943:Fatty Acid Desaturases