The effect of ascorbate on essential fatty acid composition in B16 melanoma cells.

Ascorbate has been shown to be involved in essential fatty acid (EFA) metabolism, resulting in the suggestion that the effect of ascorbate on cell growth may be mediated through an influence on the metabolism of these FAs. This study examined the effect of ascorbate, supplemented over the nutritional concentration range of 0-100 micrograms/ml, on the in vitro cell growth of non-malignant LLCMK (monkey kidney) cells and malignant B16 murine melanoma cells. The effect of ascorbate on EFA composition was also investigated, and involved the determination of the levels of linoleic acid (LA), gamma-linoleic acid (GLA), dihomogammalinolenic acid (DGLA) and arachidonic acid (AA) present in the stroma and membrane of the two cell types. Ascorbate had no significant inhibitory or stimulatory effect on the growth of either the LLCMK or B16 cells. EFA levels detected in the LLCMK cells were generally higher than those detected in the B16 cells. The % composition of the various EFAs in the stroma fractions of the two cell types were higher than the level of the corresponding EFAs in the membrane fractions. GLA levels were not detectable in the membrane fractions of the B16 cells. AA % composition determined in both cell types, was greater than that of any other EFA % composition.