a1 Program in Integrative Nutrition and Complex Diseases, Texas A&M University, College Station, TX, USA
a2 Vegetable Fruit Improvement Center, Texas A&M University, College Station, TX, USA
a3 Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX, USA
a4 Center for Environmental and Rural Health, Texas A&M University, College Station, TX 77843-2253, USA
a5 Department of Mathematics and Informatics, Sofia University “Kl. Ohrdiski”, Sofia, Bulgaria
a6 Department of Microbial and Molecular Pathogenesis, Texas A&M University Health Science Center, College Station, TX 77840, USA
a7 Department of Veterinary Pathobiology, Texas A&M University, College Station, TX, USA
a8 Department of Statistics, Texas A&M University, College Station, TX, USA
Abstract
Both fish oil (FO) and curcumin have potential as anti-tumour and anti-inflammatory agents. To further explore their combined effects on dextran sodium sulphate (DSS)-induced colitis, C57BL/6 mice were randomised to four diets (2 × 2 design) differing in fatty acid content with or without curcumin supplementation (FO, FO+2 % curcumin, maize oil (control, MO) or MO+2 % curcumin). Mice were exposed to one or two cycles of DSS in the drinking-water to induce either acute or chronic intestinal inflammation, respectively. FO-fed mice exposed to the single-cycle DSS treatment exhibited the highest mortality (40 %, seventeen of forty-three) compared with MO with the lowest mortality (3 %, one of twenty-nine) (P = 0·0008). Addition of curcumin to MO increased (P = 0·003) mortality to 37 % compared with the control. Consistent with animal survival data, following the one- or two-cycle DSS treatment, both dietary FO and curcumin promoted mucosal injury/ulceration compared with MO. In contrast, compared with other diets, combined FO and curcumin feeding enhanced the resolution of chronic inflammation and suppressed (P < 0·05) a key inflammatory mediator, NF-κB, in the colon mucosa. Mucosal microarray analysis revealed that dietary FO, curcumin and FO plus curcumin combination differentially modulated the expression of genes induced by DSS treatment. These results suggest that dietary lipids and curcumin interact to regulate mucosal homeostasis and the resolution of chronic inflammation in the colon.
(Received October 25 2010)
(Revised January 10 2011)
(Accepted January 11 2011)
(Online publication March 15 2011)
Key Words:
Correspondence:
c1 Corresponding author: Dr R. S. Chapkin, fax +1 979 862 2378, email r-chapkin@tamu.edu
Footnotes
Abbreviations: COX, cyclo-oxygenase; DSS, dextran sodium sulphate; FO, fish oil; FO-cur, fish oil plus curcumin; IBD, inflammatory bowel diseases; iNOS, inducible nitric oxide synthase; MO, maize oil; MO-cur, maize oil plus curcumin; TUNEL, terminal deoxynucleotidyl transferase-mediated uridine 5′triphosphate-biotin nick-end labelling