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.
Institute of Human Nutrition, University of Southampton, United Kingdom.
F A
FA
Wallace
E A
EA
Miles
C
C
Evans
T E
TE
Stock
P
P
Yaqoob
P C
PC
Calder
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