Effects of a high fat or a balanced omega 3/omega 6 diet on cytokines levels and DNA damage in experimental colitis.
OBJECTIVE
High-fat diets have been shown to be a risk factor for ulcerative colitis (UC). Omega-6 polyunsaturated fatty acids are considered to increase lipid peroxidation, while the omega-3 polyunsaturated fatty acid exerts a chemopreventative effect. We evaluated the effect of high-fat diets (20%) enriched with fish or soybean oil on colonic inflammation and DNA damage in dextran sulfate sodium-induced colitis.


METHODS
Male Wistar rats (28-30 days) were fed an American Institute of Nutrition (AIN)-93 diet for 47 days and divided into five groups: control normal fat non-colitic (C) or control colitis (CC), high soybean fat group (HS) colitis, high fish fat group colitis, or high-fat soybean plus fish oil colitis. UC was induced from day 35 until day 41 by 3% dextran sulfate sodium. On day 47, the rats were anesthetized; blood samples collected for corticosterone determination, and the distal colon was excised to quantify interleukin-4 (IL-4), IL-10, and interferon-gamma levels, myeloperoxidase activity, histological analyses, and DNA damage. The disease activity index was recorded daily.


RESULTS
The disease activity index, histological analysis, myeloperoxidase activity, IL-4, interferon-gamma, and corticosterone levels did not differ among the colitic groups. IL-10 was significantly increased by the high fish fat group diet in relation to HS, but only the high soybean-fish fat diet increased the IL-10/IL-4 ratio (anti-inflammatory/pro-inflammatory) to levels closer to the C group and reduced DNA damage compared to the HS group (P<0.05).


CONCLUSIONS
The data show that high-fat diets did not exacerbate UC and suggest that the soybean and fish oil mixture, more than the fish oil alone, could be a complementary therapy to achieve a cytokine balance in UC.
Vieira de Barros
Karina
K
Department of Physiology, Federal University of São Paulo, São Paulo, SP, Brazil.
Gomes de Abreu
Gilclay
G
Xavier
Roberta Araujo Navarro
RA
Real Martinez
Carlos Augusto
CA
Ribeiro
Marcelo Lima
ML
Gambero
Alessandra
A
de Oliveira Carvalho
Patrícia
P
Silveira
Vera Lúcia Flor
VL
D000818:Animals; D003093:Colitis, Ulcerative / Q000139:chemically induced*; D003106:Colon / Q000473:pathology; D004249:DNA Damage; D016264:Dextran Sulfate / Q000633:toxicity; D004032:Diet; D004041:Dietary Fats / Q000008:administration & dosage*; D004195:Disease Models, Animal; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage*; D043371:Fatty Acids, Omega-6 / Q000008:administration & dosage*; D005395:Fish Oils / Q000494:pharmacology; D007371:Interferon-gamma / Q000097:blood; D016753:Interleukin-10 / Q000097:blood; D015847:Interleukin-4 / Q000097:blood; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012307:Risk Factors; D013024:Soybean Oil / Q000494:pharmacology
D004041:Dietary Fats; D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D005395:Fish Oils; D016753:Interleukin-10; D015847:Interleukin-4; D013024:Soybean Oil; D007371:Interferon-gamma; D016264:Dextran Sulfate