12(S)-HETE is a product of arachidonic acid metabolism through the 12-lipoxygenase pathway. It is primarily found in platelets, leukocytes, and to a lesser extent in smooth muscle cells. It enhances tumor cell adhesion to endothelial cells, fibronectin, and the subendothelial matrix. tetranor-12(S)-HETE is the major β-oxidation product resulting from peroxisomal metabolism of 12(S)-HETE in numerous tissues, and Lewis lung carcinoma cells. No biological function has yet been determined for tetranor-12(S)-HETE. Some data indicate it may play a role in controlling the inflammatory response in injured corneas. In some diseases (e.g., Zellweger's Syndrome) peroxisomal abnormalities result in the inability of cells to metabolize 12(S)-HETE, which may be responsible for symptoms of the disease. The tetranor derivative of 12(S)-HETE is available as a research tool for the elucidation of the metabolic fate of its parent compound.

12(S)-HETE is the predominant lipoxygenase product of mammalian platelets. [1] It enhances tumor cell adhesion to endothelial cells, fibronectin, and the subendothelial matrix at 0.1μM181M.[2][3]

12-OxoETE is synthesized by human platelets and Aplysia nervous tissue after incubation with arachidonic acid. Microsomal fractions of various tissues will reduce 12-oxoETE to 12(S)-HETE or a mixture of 12(S)- and 12(R)-HETE. 12-OxoETE induces a rapid, dose dependent increase of cytoplasmic free calcium via a leukotriene B4 receptor or a common activation sequence.

(±)12-HEPE is produced by non-enzymatic oxidation of EPA. It contains equal amounts of 12(S)-HEPE and 12(R)-HEPE. The biological activity of (±)12-HEPE is likely mediated by one of the individual isomers, most commonly the 12(S) isomer in mammalian systems. 12-HEPE inhibits platelet aggregation with the same potency as 12-HETE, exhibiting IC50 values of 24 and 25 µM, respectively. [1] These compounds are also equipotent as inhibitors of U46619-induced contraction of rat aorta (IC50s = 8.6-8.8 µM).[2]

5(S),12(S)-DiHETE is a natural bioactive lipid derived from arachidonic acid . It is synthesized by glycogen-induced rabbit peritoneal polymorphonuclear leukocytes (PMNLs) incubated with AA. 5(S),12(S)-DiHETE can be produced by successive oxygenation of AA by 5-lipoxygenase (5-LO) in platelets and 12-LO in leukocytes. It can also be synthesized from 12(S)-HETE by 5-LO, in the presence of 5-LO activating protein (FLAP), activated with calcium ionophore. 5(S),12(S)-DiHETE is an epimer of leukotriene B4 that is weakly chemotactic for PMNL.

N-Arachidonoyl taurine is an arachidonoyl amino acid. It is oxygenated by 12(S)- and 15(S)-lipoxygenase and is converted to 12-HETE-taurine (12-HETE-T) in murine resident peritoneal macrophages. N-Arachidonoyl taurine is an activator of the transient receptor potential vanilloid (TRPV) channels TRPV1 and TRPV4 (EC50s = 28 and 21 μM, respectively). It increases calcium flux in HIT-T15 pancreatic β-cells and INS-1 rat islet cells when used at a concentration of 10 μM and increases insulin secretion from 832/13 INS-1 pancreatic β-cells. The levels of N-arachidonoyl taurine are changed in mouse brain following administration of δ9-tetrahydrocannabinol (δ9-THC).

Lobaric acid is a depsidone metabolite that has been isolated from Stereocaulon lichen species with antioxidant, antiproliferative, antiviral, and enzyme inhibitory activites. It scavenges superoxide radicals in a cell-free assay (IC50 = 97.9 μmol) and inhibits proliferation in a panel of leukemia, colorectal, gastric, breast, ovarian, prostate, pancreatic, and lung cancer cell lines (EC50s = 15.2-63.9 μg/ml). Lobaric acid inhibits protein tyrosine phosphatase 1B (PTP1B; IC50 = 0.87 μM for the human recombinant enzyme) and production of 12(S)-HETE (Item No. 34570) by 12(S)-lipoxygenase (IC50 = 28.5 μM). In vivo, lobaric acid (250 μM) decreases lesion number, but not lesion diameter, in tobacco leaves infected with tobacco mosaic virus (TMV).

15(S)-HpETE is a monohydroperoxy polyunsaturated fatty acid (PUFA) produced by the action of 15-lipoxygenase (15-LO) on arachidonic acid. It is either metabolized to 14,15-leukotriene A4 [1] or reduced to 15(S)-HETE by peroxidases.[2] [1] 15(S)-HpETE mediates a number of biological functions including the induction of c-fos and c-jun, and activation of AP-1. [3] 15(S)-HpETE inhibits prostacyclin synthesis in porcine aortic microsomes and bovine endothelial cells, and can cause the suicide inactivation of porcine 12-LO.[2][4][5]

12(S)-HpETE is a monohydroperoxy polyunsaturated fatty acid (PUFA) produced by the action of platelet or leukocyte 12-lipoxygenase (12-LO) on arachidonic acid. It activates human blood leukocyte 5-LO, resulting in the synthesis of 5(S)-HETE, leukotriene B4 (LTB4), and 5(S),12(S)-DiHETE. Rat lung metabolizes 12(S)-HpETE to 8,11,12- and 10,11,12-trihydroxyeicostrienoic acids. 12(S)-HpETE is the mediator of many biological functions, including induction of c-fos and c-jun, activation of AP-1, and endothelium-dependent vasoconstriction. It mediates the inhibitory synaptic response to FMRF-amide in Aplysia sensory neurons and inhibits Ca2+/calmodulin-dependent protein kinase II from rat brain cortex.

9(S)-HETE is an enantiomer which makes up 50% of (±)9-HETE . There are no reports of 9(S)-HETE occurring as an enzymatic lipoxygenation product. Whereas 12(S)-HETE promotes adhesion of several cell lines to endothelial cell monolayes, 9(S)-HETE and other positional HETEs are without effect. Stereochemical assignment of the (S) enantiomer is based on comparison of chiral HPLC retention times to published results.

12(R)-HEPE, a monohydroxy fatty acid derived from EPA in the eggs of the sea urchin S. purpuratus, has a biological activity that, while not extensively documented, may resemble that of 12(R)-HETE (Catalog No.34560).