A soybean and ﬁsh oil mixture modulates the inﬂammatory reaction
In some recent research, a group of researchers from across Taiwan investigated the impact of different ratios of soybean and fish oil mixtures upon inflammatory reactions in mice with dextran sulfate sodium-induced acute colitis.
Team: Cyoung-Huei Huang, Yu-Chen Hou, Chiu-Li Yeh, Sung-Ling Yeh
Background & aims
Inﬂammatory bowel disease is a recurrent disease of the gastrointestinal tract. n-3 polyunsaturated fatty acids (PUFAs) are proved to have anti-inﬂammatory and immunomodulatory properties. This study evaluated the effects of different dietary n-6/n-3 PUFA ratios on the mechanism of alleviating the inﬂammatory response in mice with dextran sulfate sodium (DSS)-induced colitis.
Mice were randomly assigned to 6 groups including 3 non-colitis groups (C, LF, and HF) and 3 colitis groups (DC, DLF, and DHF). Mice in the C and DC groups were fed a common semipuriﬁed diet with soybean oil as the fat source. The other groups received an identical component except that part of the soybean oil was replaced by different amounts of ﬁsh oil. The n-6/n-3 PUFA ratio of the LF and DLF groups was 4:1, the ratio of the HF and DHF groups was 2:1. After feeding the respective diets for 2 weeks, the colitis groups were given distilled water containing 2% DSS, while the non-colitis groups were given distilled water for 5 days. After that, all mice were sacriﬁced at the recovery phase after drinking distilled water for another 5 days.
Colitis resulted in higher expressions of colonic inﬂammatory mediators in colon tissues and colon lavage ﬂuid. Also, colonic peroxisome proliferator-activated receptor (PPAR)-g and the IkBa/nuclear factor (NF)-kB p65 ratio were lower than those of the non-colitis groups. Compared to the DC group, ﬁsh oil-enriched colitis groups had lower inﬂammatory mediator expressions and higher PPAR-g protein levels and IkBa/NF-kB p65 ratios in colon tissues. The DHF group had even lower colonic inﬂammatory gene and higher PPAR-g protein expressions than did the DLF group. Conclusions: These ﬁndings suggest that diets enriched with ﬁsh oil upregulated PPAR-g and decreased NF-kB activation that may consequently have reduced luminal inﬂammatory mediator production. Compared to a n-6/n-3 PUFA ratio 4:1, a ratio of 2:1 was more effective in reducing inﬂammatory re- actions in DSS-induced colitis.