Fatty acid compositions of lipids in mesenteric adipose tissue and lymphoid cells in patients with and without Crohn's disease and their therapeutic implications.
BACKGROUND
The physiological bases for roles of adipose tissue and fatty acids in the symptoms and dietary treatments of Crohn's disease (CD) are poorly understood. The hypothesis developed from experiments on rodents that perinodal adipocytes are specialized to provision adjacent lymphoid tissues was tested by comparing the composition of triacylglycerol and phospholipid fatty acids in homologous samples of mesenteric adipose tissue and lymph nodes from patients with or without CD.


METHODS
Mesenteric perinodal and other adipose tissue and lymph nodes were collected during elective surgery for CD and other conditions. Fatty acids were extracted, identified, and quantified by thin-layer and gas-liquid chromatography.


RESULTS
Perinodal adipose tissue contained more unsaturated fatty acids than other adipose tissue in controls, as reported for other mammals, but site-specific differences were absent in CD. Lipids from adipose and lymphoid tissues had more saturated fatty acids but fewer polyunsaturates in patients with CD than controls. In adipose tissue samples, depletion of n-3 polyunsaturates was greatest, but n-6 polyunsaturates, particularly arachidonic acid, were preferentially reduced in lymphoid cells. Ratios of n-6/n-3 polyunsaturates were higher in adipose tissue but lower in lymphoid cells in patients with CD than in controls.


CONCLUSIONS
Site-specific differences in fatty acid composition in normal human mesentery are consistent with local interactions between lymph node lymphoid cells and adjacent adipose tissue. These site-specific properties are absent in CD, causing anomalies in composition of lymphoid cell fatty acids, which may explain the efficacy of elemental diets containing oils rich in n-6 polyunsaturates.
Westcott
Edward
E
Antigen Presentation Research Group, Imperial College, London, United Kingdom.
Windsor
Alastair
A
Mattacks
Christine
C
Pond
Caroline
C
Knight
Stella
S
D000273:Adipose Tissue / Q000737:chemistry*; D000328:Adult; D016022:Case-Control Studies; D002849:Chromatography, Gas; D002853:Chromatography, Liquid; D002855:Chromatography, Thin Layer; D003424:Crohn Disease / Q000503:physiopathology*; D005227:Fatty Acids / Q000032:analysis*; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000737:chemistry*; D008297:Male; D008643:Mesentery; D008875:Middle Aged
D005227:Fatty Acids