The Effect of Alpha-Linolenic Acid-Rich Emulsion on Fatty Acid Metabolism and Leukotriene Generation of the Colon in a Rat Model with Inflammatory Bowel Disease.
The Effect of Alpha-Linolenic Acid-Rich Emulsion on Fatty Acid Metabolism and Leukotriene Generation of the Colon in a Rat Model with Inflammatory Bowel Disease.
Year: 1996
Authors: K Inui, Y Fukuta, A Ikeda, H Kameda, Y Kokuba, M Sato.
Publication Name: Nutr. Metab.
Publication Details: Volume 40; Number 3; 175.
Abstract:
This paper is a continuation of earlier work (Inui, et al. 1996. Ann. Nutr. Metab. 40:227 in which the authors were interested in determining the anti-inflammatory effects of a perilla oil emulsion high in ALA. A rat model of inflammatory bowel disease (IBD) was used in this initial study to determine whether ALA could improve nutritional status and alleviate inflammation. The results showed improvement in disease damage to the colon following the POE diet. Better weight gains and reduced inflammation were also noted. However, in this study the generation of the eicosanoid LTB4 was not measured so it was difficult to determine the mechanisms potentially responsible for the beneficial effects of ALA. LTB4 is both a powerful pro-inflammatory eicosanoid and a potent chemoattractant for neutrophils. The synthesis of LTB4 has been found to be elevated at the site of inflammatory lesions in patients with IBD. In the present study, a perilla oil emulsion (POE) was again compared to a soybean oil emulsion (SOE) in a rat model with trinitrobenzensulfonic acid (TNB)-induced IBD. The SOE and POE were infused for 14 days after instillation of TNB. After infusion, TC and PL concentrations in the plasma in the POE group were significantly decreased compared with the SOE group. In untreated animals with IBD, AA synthesis was enhanced as was the generation of LTB4. AA levels in colonic PLs were significantly decreased and EPA levels were significantly increased in the POE group compared with the SOE group. Thickness, damage score and LTB4 generation in the colon of the POE group were significantly lower in comparison to the SOE group. These results suggest that ALA suppresses the synthesis of LTB4 in the colon through modifications of the FA composition of colonic PLs. The results confirmed the observations of the earlier study and indicate that ALA appears to be an effective treatment for inflammation in the colon associated with IBD. In addition, ALA is an effective inhibitor of n-6 PUFA metabolism as well as the synthesis of LTB4 at the site of inflammatory lesions in the colon.
