Dietary fatty acids influence the production of Th1- but not Th2-type cytokines.
C57B16 mice were fed for 6 weeks on a low-fat diet or on high-fat diets containing coconut oil (rich in saturated fatty acids), safflower oil [rich in n-6 polyunsaturated fatty acids (PUFAs)], or fish oil (rich in n-3 PUFAs) as the main fat sources. The fatty acid composition of the spleen lymphocytes was influenced by that of the diet fed. Thymidine incorporation into concanavalin A-stimulated spleen lymphocytes and interleukin (IL)-2 production were highest after feeding the coconut oil diet. Interferon (IFN)-gamma production was decreased by safflower oil or fish oil feeding. IL-4 production was not significantly affected by diet, although production was lowest by lymphocytes from fish oil-fed mice. The ratio of production of Th1- to Th2-type cytokines (determined as the IFN-gamma/IL-4 ratio) was lower for lymphocytes from mice fed the safflower oil or fish oil diets. After 4 h of culture, IL-2 mRNA levels were higher in cells from mice fed coconut oil, and IFN-gamma mRNA levels were higher in cells from mice fed coconut oil or safflower oil. After 8 h of culture, IL-2, IFN-gamma, and IL-4 mRNA levels were lowest in cells from mice fed fish oil. The ratio of the relative levels of IFN-gamma mRNA to IL-4 mRNA was highest in cells from mice fed coconut oil and was lowest in cells of mice fed fish oil. The influence of individual fatty acids on IL-2 production by murine spleen lymphocytes was examined in vitro. Although all fatty acids decreased IL-2 production in a concentration-dependent manner, saturated fatty acids were the least potent and n-3 PUFAs the most potent inhibitors, with n-6 PUFAs falling in between in terms of potency. It is concluded that saturated fatty acids have minimal effects on cytokine production. In contrast, PUFAs act to inhibit production of Th1-type cytokines with little effect on Th2-type cytokines; n-3 PUFAs are particularly potent. The effects of fatty acids on cytokine production appear to be exerted at the level of gene expression.
Wallace
F A
FA
Institute of Human Nutrition, University of Southampton, United Kingdom.
Miles
E A
EA
Evans
C
C
Stock
T E
TE
Yaqoob
P
P
Calder
P C
PC
D000818:Animals; D000074263:Coconut Oil; D003208:Concanavalin A / Q000494:pharmacology; D004041:Dietary Fats / Q000494:pharmacology*; D005395:Fish Oils / Q000494:pharmacology; D007371:Interferon-gamma / Q000096:biosynthesis* / Q000235:genetics; D007376:Interleukin-2 / Q000096:biosynthesis* / Q000235:genetics; D015847:Interleukin-4 / Q000096:biosynthesis* / Q000235:genetics; D008213:Lymphocyte Activation / Q000187:drug effects; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010938:Plant Oils / Q000494:pharmacology; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D012450:Safflower Oil / Q000494:pharmacology; D013154:Spleen / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D018417:Th1 Cells / Q000276:immunology / Q000378:metabolism*; D018418:Th2 Cells / Q000276:immunology / Q000378:metabolism*
D004041:Dietary Fats; D005395:Fish Oils; D007376:Interleukin-2; D010938:Plant Oils; D012333:RNA, Messenger; D003208:Concanavalin A; D015847:Interleukin-4; D012450:Safflower Oil; D007371:Interferon-gamma; D000074263:Coconut Oil