Arachidonic acid is an omega-6 fatty acid found in a number of foods. I think most Americans consume too much of this fatty acid.
Arachidonic acid and prostate
cancer
Adding arachidonic acid, a common omega-6
polyunsaturated fatty acid, to culture media causes prostate cancer cells to
grow twice as fast. The omega-6
turns on a dozen inflammatory genes that are known to be important in cancer
progression. Arachidonic acid activates these genes
through the "PI3-kinase" pathway, which is known to play a key role in the
pathogenesis of cancer.
Adding a nonsteroidal anti-inflammatory drug or a PI3-kinase inhibitor to the
culture media blocks the arachidonic acid-induced growth of prostate cancer
cells.
Omega-6 versus omega-3 fatty
acids and health effects
Studies indicate that a high intake of omega-6 fatty acids shifts the
physiologic state to one that encourages blood clotting and platelet
aggregation, increases in blood viscosity, spasm of blood vessels, and
vasoconstriction. Omega-3 fatty acids, however, have antiinflammatory,
blood thinning, antiarrhythmic, hypolipidemic, and vasodilatory (blood vessel
dilating) properties.
Avoid arachidonic acid
Corn oil is known to be high in omega-6 fatty acids. Canola oil, olive oil
and flax seed oil are better options.
Pathway in Mast Cells
When activated by diverse stimuli, mast cells mobilize arachidonic acid through
cytosolic phospholipase A2, and rapidly generate both prostaglandin D2 and
leukotriene C4, the parent molecule of the cysteinyl LTs. While initially
recognized for their bronchoconstricting and vasoactive properties, these two
eicosanoids are now known to serve diverse and pivotal functions in effector
cell trafficking, antigen presentation, immune cell activation, matrix
deposition, and fibrosis.
Prostaglandins (PGs) are products of the COX pathway of arachidonic acid metabolism. There are five primary PGs, PGD2, PGE2, PGF2, PGI2 and thromboxane A2, all of which signal through distinct seven transmembrane, G-protein coupled receptors. Some PGs may counteract the actions of others, or even the same PG may have opposing physiologic or immunologic effects, depending on the specific receptor through which it signals.
Arachidonic acid metabolism
The metabolism of arachidonic acid can be catalysed by either one of two
enzyme families: the cyclooxygenases or the lipoxygenases. The lipoxygenase
enzymes are classed into several subcategories including 5-, 12- and
15-lipoxygenases. The 5-lipoxygenase pathway has been the major focus of study
due to the pronounced pro-inflammatory role of leukotrienes and the approval of
5-lipoxygenase inhibitors and leukotriene receptor antagonists for the clinical
treatment of asthma. Although less well characterized, the 12-lipoxygenase as
well as the 15-lipoxygenase pathway may also play an important role in the
progression of human diseases such as cancer, psoriasis and atherosclerosis.