[Immunonutrition in experimental colitis: beneficial effects of omega-3 fatty acids].
BACKGROUND
Recent data have given emphasis to the benefits of immunonutrition with omega-3 fatty acids (n-3 FA) in various clinical situations. This work presents the results of parenteral administration of different lipid emulsions in experimental acute colitis and reviews the pertinent literature.


METHODS
Seventy-four adult male Wistar rats were randomized in six groups that had 10% acetic acid-induced colitis (except CS). During 7 days, control groups CS (without colitis) and CC (with colitis) received physiological solution and the others received specific lipid emulsion by a central venous catheter (0.5 mL/h). The n-3/n-6 FA ratio and lipidic compositions were: group L--1:7.7 (LCT, n = 12), M--1:7.0 (MCT and LCT, n = 12), LW-3--1:4.5 (LCT plus FO, n = 12) and MW-3--1:3.0 (MCT and LCT plus FO, n = 13). Rats were evaluated to assess abdominal and intestinal alterations, macrophage cellularity and colonic concentrations of LTB4, LTC4, PGE2 and TXB2.


RESULTS
N-3 FA treated rats (LW-3 and MW-3) presented less inflammatory abdominal alterations than CC rats. Mucosal ulcer formation in MW-3 group was the only comparable to CS group. Only CS, M and MW-3 rats presented smaller cellularity than CC group. Comparing to CC group, there were found smaller averages of LTB4 in CS, LW-3 and MW-3 groups, of PGE2 in CS, M and MW-3 groups, and of TXB2 in CS and MW-3 groups. LTC4 averages were not different.


CONCLUSIONS
1) LCT-containing lipid emulsion with low n-3/n-6 ratio do not modify inflammatory colitis derived manifestations; 2) the association of MCT/LCT-containing lipid emulsion with fish oil with high n-3/n-6 ratio impels great beneficial impact, attenuating morphological and inflammatory consequences and decreasing colonic concentrations of proinflammatory mediators.
Departamento de Gastroenterologia, Faculdade de Medicina, Universidade de São Paulo, Laboratório de Metabologia e Nutrição em Cirurgia, Disciplina de Coloproctologia, Faculdade de Medicina, Universidade de São Paulo. fgmcampos@terra.com.br
Fábio Guilherme
FG
Campos
Dan L
DL
Waitzberg
Angela Flávia
AF
Logulo
Raquel Susana
RS
Torrinhas
William Gemio Jacobsen
WG
Teixeira
Angelita
A
Habr-Gama
D000818:Animals; D003092:Colitis / Q000150:complications / Q000473:pathology / Q000628:therapy*; D005217:Fat Emulsions, Intravenous / Q000494:pharmacology*; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology*; D018836:Inflammation Mediators / Q000502:physiology; D008264:Macrophages; D008297:Male; D051381:Rats; D017208:Rats, Wistar
D005217:Fat Emulsions, Intravenous; D015525:Fatty Acids, Omega-3; D018836:Inflammation Mediators