15-Lipoxygenase eicosanoids are the putative ligands for vanilloid receptors and peroxisome proliferator-activated receptors (PPARs)

Abstract

We read the article by Zhao et al. (1), which showed that epithelial 15-lipoxygenase 1 (15LO1) and its product 15-hydroxyeicosatetraenoic acid phosphatidylethanolamine interact with phosphatidylethanolamine-binding protein (PEBP1) to enhance MAPK signaling (ERK activation) in human airway epithelia. This can then be seen as an internal mechanism in airway epithelium for adjusting the gain settings of critical inflammatory pathways integral to asthma pathogenesis. However, this model rests critically on three assumptions: (i) Epithelial 15LO1 is the major form of 15LO1 and the source of 15S-hydroxyeicosatetraenoic acid (15S-HETE), (ii) metabolites or eicosanoids of 15LO1 such as 15S-HETE are not released extracellularly, and (iii) these eicosanoids do not influence MAPK .