Interleukin-1 and tumor necrosis factor synthesis by mouse peritoneal macrophages is enhanced by dietary n-3 polyunsaturated fatty acids.

The peritoneal macrophages from mice maintained for 16 days on a diet containing (10%) menhaden oil contained less arachidonic acid and more n-3 polyunsaturated fatty acids (n-3 PUFA) than those maintained on diets containing an equivalent amount of corn oil. Following stimulation with lipopolysaccharide, the production of PGE2, interleukin-1 (IL-1) and tumor necrosis factor (TNF) was 2.1 vs. 5.3 ng PGE2/micrograms DNA; 685 vs. 30 units IL-1/micrograms DNA and 14 vs. less than 4 units TNF by macrophages from mice consuming menhaden and corn oil, respectively. Macrophages from animals on diets containing olive oil generated intermediate amounts of PGE2 and equivalent amounts of IL-1 and TNF to those on corn oil. The data indicate that dietary n-3 PUFA at specific intake levels relative to n-6 PUFA may enhance cytokine generation by reducing PGE2 synthesis.