9(E),11(E)-Octadecadienoic acid

9(E),11(E)-Octadecadienoic acid is a conjugated linoleic acid (CLA), an isomer of linoleic acid. CLA is found mostly in lipids originating in ruminant animals including dairy products. It has several biological properties including anticarcinogenic activity, suppressing in vitro growth of human melanoma, colorectal, and breast cancer cells, and exhibiting anti-atherogenic activity.1 It is thought that CLA itself may not have anti-oxidant capabilities but may produce substances which protect cells from the detrimental effects of peroxides. 9(E),11(E)-CLA is a minor component in natural sources of CLA and is used as a marker for free radical activity. Also, due to its being a minor component it is very helpful as a comparison to the major isomers 9(Z),11(E)-CLA and 10(E),12(Z)-CLA. 9(E),11(E)-CLA can exert anti-inflammatory effects by increasing an endogenous repressor of IL-1 signaling2. It can induce expression of genes involved in lipid metabolism of human macrophages and is a dietary occurring agonist of liver X receptor alpha.3