(±)12(13)-DiHOME is the diol form of (±)12(13)-EpOME , a cytochrome P450-derived epoxide of linoleic acid also known as isoleukotoxin. [1] It is formed from 12(13)-EpOME by solubleepoxidehydrolase (sEH) in neutrophils. [2] 12(13)-DiHOME is toxic to Sf21 cells expressing sEH and to lacZ-expressing control cells, unlike isoleukotoxin, which is only toxic to cells containing sEH.[1] [2] Levels of 12(13)-DiHOME are increased in rat spinal cord following burn injury, and it enhances cold tolerance, increases fatty acid uptake into brown adipocytes, and decreases serum triglyceride levels in mice. Levels are also elevated in bronchoalveolar lavage fluid (BALF) in humans following exposure to biodiesel exhaust and in exhaled breath condensate in patients with allergic asthma following allergen exposure.[5] [6] Plasma levels of 12(13)-DiHOME are increased immediately following moderate-intensity exercise in mice and humans, an effect that can be prevented by brown adipose tissue removal in the mouse.[7]
Cytochrome P450 metabolism of polyunsaturated fatty acids produces numerous bioactive epoxide regioisomers. (±)10(11)-EpDPA is a docosahexaenoic acid epoxygenase metabolite, derived via epoxidation of the 10,11-double bond of DHA. It has been detected in rat brain and spinal cord, as well as human serum, and acts as a substrate for solubleepoxidehydrolase with a Km value of 5.1 μM. (±)10(11)-EpDPA and other epoxy metabolites of DHA are reported to demonstrate antihyperalgesic activity in inflammatory and neuropathic pain models and to potently inhibit angiogenesis and tumor growth in in vitro assays.
Cytochrome P450 metabolism of polyunsaturated fatty acids produces numerous bioactive epoxide regioisomers. (±)13(14)-EpDPA is a docosahexaenoic acid epoxygenase metabolite, derived via epoxidation of the 13,14-double bond of DHA. It has been detected in rat brain and spinal cord and is a preferred substrate for solubleepoxidehydrolase with a Km value of 3.2 μM. (±)13(14)-EpDPA demonstrates antihyperalgesic activity in inflammatory and neuropathic pain models. (±)13(14)-EpDPA and other epoxy metabolites of DHA are also reported to potently inhibit angiogenesis and tumor growth in in vitro assays.
Docosahexaenoic acid is the most abundant ω-3 fatty acid in neural tissues, especially in the brain and retina. (±)7(8)-EpDPA is an epoxide derivative of DHA that is generated by the action of cytochrome P450 epoxygenases. It is naturally occurring in plasma and brain and spinal cord tissues and is increased following dietary supplementation with ω-3 fatty acids. (±)7(8)-EpDPA and other epoxy metabolites of DHA modulate receptor and channel activities to evoke diverse effects, such as promoting vasodilation, inhibiting angiogenesis, and decreasing inflammatory and neuropathic pain. (±)7(8)-EpDPA is a substrate of solubleepoxidehydrolase (KM = 15 μM), which converts it to the corresponding diol.