Attenuation of colonic inflammation by partial replacement of dietary linoleic acid with α-linolenic acid in a rat model of inflammatory bowel disease.

Abstract

Increasing prevalence of inflammatory bowel disease may be due to imbalance in the intake of n-6 and n-3 PUFA in the diet. This study investigates the impact of varying ratios of dietary linoleic acid (LA, 18 : 2n-6) to α-linolenic acid (ALA, 18 : 3n-3) on the inflammatory response in dextran sulphate sodium (DSS)-induced colitis. Weanling male Sprague-Dawley rats were divided into five groups: a non-colitic group with a LA:ALA ratio of 215 (CON-215), and colitic groups with LA:ALA ratios of 215 (DSS-215), 50 (DSS-50), 10 (DSS-10) and 2 (DSS-2). Blends of groundnut, palmolein and linseed oils were used to provide varying LA:ALA ratios. All the rats were fed the respective experimental isoenergetic diets containing 10 % fat for 90 d and DSS was administered during the last 11 d. Colonic inflammation was evaluated by clinical, biochemical and histological parameters. The results showed attenuation of colitis in the DSS-2 group as evidenced by significant reductions in disease activity index, mucosal myeloperoxidase activity (P < 0·05), alkaline phosphatase activity (P < 0·01) and increase in colon length (P < 0·01) compared to the groups fed with higher ratios (DSS-215). This was accompanied by significant reductions in mucosal proinflammatory cytokines TNF-α (P < 0·01) and IL-1β (P < 0·01) and improvement in the histological score. Further, ALA supplementation increased long-chain (LC) n-3 PUFA and decreased LC n-6 PUFA in colon structural lipids. These data suggest that substitution of one-third of LA with ALA (LA:ALA ratio 2) mitigates experimental colitis by down-regulating proinflammatory mediators.

• Authors: Anupama Tyagi, Uday Kumar, Suryam Reddy, Vadakattu S Santosh, Saazida B Mohammed, Nasreen Z Ehtesham, Ahamed Ibrahim
• Journal: The British journal of nutrition (Br J Nutr) Vol. 108 Issue 9 Pg. 1612-22 (Nov 14 2012) ISSN: 1475-2662 [Electronic] England
• PMID: 22243775 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Anti-Inflammatory Agents, Non-Steroidal
• Biomarkers
• Cytokines
• Fatty Acids, Omega-3
• Fatty Acids, Omega-6
• alpha-Linolenic Acid
• Dextran Sulfate
• Linoleic Acid

Topics

• Animals
• Anti-Inflammatory Agents, Non-Steroidal (administration & dosage, therapeutic use)
• Biomarkers (metabolism)
• Colitis (immunology, pathology, physiopathology, prevention & control)
• Colon (growth & development, immunology, metabolism, pathology)
• Cytokines (metabolism)
• Dextran Sulfate
• Dietary Supplements
• Disease Models, Animal
• Fatty Acids, Omega-3 (metabolism)
• Fatty Acids, Omega-6 (metabolism)
• Inflammatory Bowel Diseases (immunology, pathology, physiopathology, prevention & control)
• Intestinal Mucosa (growth & development, immunology, metabolism, pathology)
• Linoleic Acid (administration & dosage)
• Male
• Neutrophil Infiltration
• Random Allocation
• Rats
• Rats, Sprague-Dawley
• Severity of Illness Index
• Weaning
• alpha-Linolenic Acid (administration & dosage, therapeutic use)