Abnormal expression of oxylipins and related synthesizing/signaling pathways in inflammatory bowel diseases.

We investigated selected oxylipins and related synthesizing/signaling pathways in 28 patients with Crohn's disease (CD), 19 patients with ulcerative colitis (UC), and 39 controls. Plasma and mucosal PUFA/oxylipin profiles were analyzed by LC-MS/MS. mRNA expression of 5, 12 and 15-lipooxygenases, FPR2/ALXR, FFAR4/GPR120, annexin A1, and interleukin-10 were analyzed by qRT-PCR. Oxylipin profile and related metabolic pathways were altered in both CD and UC patients. The patterns were characterized by increased prostaglandins, leukotrienes, and lipoxins and overexpression of 5-lipoxygenase, FPR2/ALXR, annexin A1, and interleukin-10 genes, but decreased n-3 PUFAs and 18-hydroxyeisapentaenoic acid. The gene of 15-lipoxygenase was under-expressed mainly in UC patients. CD and UC are associated with unbalanced n-6 ​​and n-3 derivatives and pro-inflammatory and anti-inflammatory/pro-resolving mediators favoring the former compounds. The findings suggest that oxylipins engage in the pathophysiology of the diseases. Targeting oxylipin's metabolic pathways would be a promising therapy for inflammatory bowel diseases.

Altered mucosal and plasma polyunsaturated fatty acids, oxylipins, and endocannabinoids profiles in Crohn's disease.

Selected mucosal and plasma polyunsaturated fatty acids (PUFAs) and related oxylipins and endocannabinoids were determined in 28 Crohn's disease (CD) patients and 39 controls. Fasting blood and colonic biopsies were collected in all participants, during a disease flare for the patients. Thirty-two lipid mediators including PUFAs, oxylipins, and endocannabinoids were assessed by LC-MS/MS. The pattern of lipid mediators in CD patients is characterized by an increase in arachidonic acid-derived oxylipins and endocannabinoids and a decrease in n-3 PUFAs and related endocannabinoids. A model combining increased 6-epi-lipoxin A4 and 2-arachidonyl glycerol with decreased docoasapentaenoic acid in plasma fairly discriminates patients from controls and may represent a lipidomic signature for CD flare. The study findings suggest that lipid mediators are involved in CD pathophysiology and may serve as biomarkers for disease flare. Further research is required to confirm the role of these bioactive lipids and test their therapeutic potential in CD.