Hydroxyeicosatetraenoic acids
Hydroxyeicosatetraenoic acids (HETEs) regulate vasoconstriction in many tissues. Alterations in HETEs have been associated with vascular diseases including ischemia and hypertension, indicating that these eicosanoids are important in cardiovascular function (Miyata & Roman, 2005).
They may also play a role in cancer biology (Panigraphy et al., 2010).Platelet activating factor
When phospholipase A2 cleaves AA from phospholipids, platelet activating factor (PAF) is formed. PAF is produced by leukocytes, platelets, and vascular endothelium. It causes platelets and leukocytes to aggregate and adhere to vascular endothelium, inducing leukocytes to marginate and become pavemented to the endothelial surface. PAF causes leukocytes to release enzymes and free radicals. It also has a role in increasing vascular permeability (Uhlig et al., 2005).
Reactive oxygen species
Reactive oxygen species are by-products of oxidative metabolism and are produced by nearly all cells. Reactive oxygen intermediates (ROIs) include O2 − and OH− (free radicals), which cause harmful effects to cells through DNA damage, lipid peroxidation, the oxidation of proteins, the oxidation of enzymatic co-factors, and the release of inflammatory cytokines. Cells have several defenses against ROIs. Superoxide dismutases, catalase, glutathione peroxidase, lactoperoxidase, peroxiredoxins, and α1-microglobulin enzymatically reduce ROIs and prevent oxidative damage to cells (Bartz & Piantadosi, 2010). Other antioxidants in the body include vitamins C and E, uric acid, glutathione, and polyphenol antioxidants, which neutralize harmful free radicals.