FIG. 15.

A schema illustrating the TBI-induced signaling pathways as well as the formation and metabolic conversions of lipid mediators and their targets in the intestinal epithelium. (A) Production of chemotactic lipid mediator, LTB4, and its appearance in the circulation is essential for the recruitment of polymorphonuclear leukocytes (PMNs) to the site of damage. (B) Intestinal epithelial cells generate free and esterified forms of HXA₃. MRP2 that is highly expressed at the apical surface of the intestinal epithelia pumps out free HXA₃ that acts as a signal for neutrophils guiding their movements through the mucosal layer (1). (C) Finally, the formation of AA-OOH-PE triggers ferroptotic death of epithelial cells. MRP2, multidrug resistance-associated protein 2. To see this illustration in color, the reader is referred to the web version of this article at www.liebertpub.com/ars