Immune regulation leukotrienes

Lewis, R. A. Interactions of eicosanoids and cytokines in immune regulation. Adv. Prostaglandin, Thromboxane, Leukotriene Res. 20, 170-178 (1990). 

Although it appears that severe IL-4-regulated enteropathy is not required for immune expulsion of T. spiralis, it is still possible that Th2 cytokines can act in a direct fashion to create an environment unfavourable for intestinal parasites. It remains to be shown directly whether these effects are sufficient to expel parasites. Indeed, there is considerable evidence to support a variety of pathophysiological effects of IL-4 and/or TNF on the gut. These effects may be mediated by factors including cytokines and mast-cell products (e.g. leukotrienes and 5-hydroxytryptamine). 7. spiralis infections result in increased fluid and mucus secretion into the lumen as well as increased intestinal propulsive activity and more rapid intestinal transit (Castro et al, 1979 Russell, 1986 Vermillion and Collins, 1988 Vermillion et al., 1991 Weisbrodt et al, 1994 Barbara et al, 1997). The increased contractility of radial and longitudinal muscle is greater in high-... 

Regulation of dendritic cell migration and adaptive immune response by leukotriene B4 receptors a role for LTB4 in up-regulation of CCR7 expression and function. Blood 2007 109 ... 

The alteration of lipid mediators by PUFA has been reviewed in great detail (Stulnig, 2003) and is mentioned only briefly here. The function of cells of the immune system can be exquisitely sensitive to lipid mediators such as prostaglandins and leukotrienes. Those mediators are normally produced by the action of specific enzyme systems on the AA substrate that is released from membrane phospholipids pools. Thus, cyclooxygenase (COX-1 or COX-2) converts AA to prostaglandins, and lipoxygenase (e.g., 5-LOX) converts AA to HETEs and leukotrienes. The amount of substrate, the activity of the enzymes, and the amount and potency of the lipid mediators appear to be regulated by FA composition and, thus, the dietary intake of PUFA. Specifically, EPA is and DHA is not a substrate for COX and LOX and can competitively inhibit AA metabolism. In addition, DHA can inhibit... 

Eicosanoids Hormone-like compounds, including prostaglandins, thromboxanes, lipoxins, and leukotrienes, which are involved in many important biological processes in the human body (i.e., central nervous funchon, regulation of blood pressure, regulation of other hormones, inhammatory reactions, and immune response). They are produced mainly through the metabohsm of arachidonic acid and eicosapentaenoic acid,although other fatty acids may also be similarly metabolized. 

Previous investigation (3) indicated that tl0,cl2 CLA reduced lipid accumulation in adipocytes in part by inhibiting heparin-releasable lipoprotdn lipase (LPL) activity. CLA was also known to affect eicosanoid-regulated immune system effects, presumably by regulating the levels of inducible prostanoids and leukotrienes (7-9). Accordingly we investigated the possibility of a link between the effects of tl0,cl2 CLA and the regulation of LOX pathways. 

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