Table 1.

Summary of the metabolites from essential PUFAs involved in the inflammatory processes in the skin

Metabolite	Pathway	Receptors	Main Biological Effects	Cellular Origin in the Skin
PGE2	COX	EP1, EP2, EP3, and EP4	Vasodilatation, chemotaxis, cell proliferation, and modulation of immune response	Epidermal keratinocytes and dermal fibroblasts
PGD2	COX	CRTH2, DP2 or GPR44	Immunomodulation (platelet aggregation)	Epidermal keratinocytes, mast cells, and Langerhans cells
PGI2	COX	IP	Vasodilatation and inhibition of platelet aggregation	Dermal fibroblasts
TXA2	COX	TP	Vasoconstriction and platelet aggregation	Epidermal keratinocytes
LTB4	5-LOX	BLT1 and BLT2	Chemotaxis	Infiltrating neutrophils and epidermal keratinocytes (lower levels)
12-HETE	12-LOX	12-HETER	Chemotaxis, leucocyte migration, cell proliferation	Epidermal keratinocytes and dermal fibroblasts
15-HETE	15-LOX	PPAR-γ	Counteract 12-HETE and LTB4 effects, reduces polymorphonuclear leukocytes infiltration, and act as biochemical precursor of LXA4	Epidermal keratinocytes, and dermal fibroblasts