Modulation of cytokine production in vivo by dietary essential fatty acids in patients with colorectal cancer.
1. The effects of essential fatty acids (gamma-linolenic acid, eicosapentaenoic acid, docosahexaenoic acid), at a dose of 4.8 g/day, given in combination as dietary supplements, on cytokine production were investigated in patients with colorectal cancer. 2. Total serum cytokines--interleukin (interleukin-1 beta, 2, 4 and 6), tumour necrosis factor-alpha and interferon-gamma--were analysed using the enzyme-linked immunosorbent assay technique at different time intervals during the course of essential fatty acid supplementation. 3. Fatty acid uptake and patient compliance were confirmed by a significant increase in serum levels of gamma-linolenic acid, eicosapentaenoic acid and docosahexaenoic acid in all three fractions: tricylglycerol, cholesterol and phospholipid. 4. There was no significant alteration in total serum cytokine concentration/levels in the first 2 months of essential fatty acid ingestion, but the levels of serum cytokines steadily declined thereafter, reaching minimum levels after 6 months of essential fatty acid supplementation. 5. Essential fatty acids, at the dose and duration (6 months) used in this study, reduced total serum interleukin-1 beta levels by 61% (P = 0.044), interleukin-2 by 63% (P = 0.05), interleukin-4 by 69% (P = 0.025), interleukin-6 by 83% (P = 0.030), tumour necrosis factor-alpha by 73% (P = 0.040) and interferon-gamma by 67% (P = 0.050). 6. Three months after cessation of essential fatty acid intake, however, these cytokine levels returned to presupplementation values. 7. This present study has shown that long-term n-3 and n-6 EFA ingestion results in a significant reduction in circulating key cytokines. The precise mechanism of this reduction is unclear.
Purasiri
P
P
Department of Surgery, Medical School, Aberdeen University, U.K.
Murray
A
A
Richardson
S
S
Heys
S D
SD
Horrobin
D
D
Eremin
O
O
D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000178:diet therapy / Q000276:immunology / Q000378:metabolism*; D016207:Cytokines / Q000378:metabolism*; D004281:Docosahexaenoic Acids / Q000008:administration & dosage; D015118:Eicosapentaenoic Acid / Q000008:administration & dosage; D004797:Enzyme-Linked Immunosorbent Assay; D005228:Fatty Acids, Essential / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D007375:Interleukin-1 / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D015847:Interleukin-4 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D017965:gamma-Linolenic Acid / Q000008:administration & dosage
D016207:Cytokines; D005228:Fatty Acids, Essential; D007375:Interleukin-1; D007376:Interleukin-2; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D015847:Interleukin-4; D004281:Docosahexaenoic Acids; D017965:gamma-Linolenic Acid; D007371:Interferon-gamma; D015118:Eicosapentaenoic Acid