Receptor signaling saturable effect

Both EPA and C14-S-acetic acid are converted to their respective CoA esters in mitochondria. Furthermore, in contrast to DHA-CoA, EPA-CoA and C14-S-acetyl-CoA are easily transferred into the mitochondria by the CAT system. EPA is more difficult to oxidize than saturated and monounsaturated fatty acids, due to the double bonds and C14-S-acetic acid is non-oxidizable by P-oxidation,due to the sulfur atom in 3-position. Thus, accumulation of their respective CoA esters in the mitochondria might give an fatty acid overload signal leading to inaeased mitochondrial fatty acid oxidation. C14-S-acetic acid mimics the effects of peroxisome proliferators such as the fibrates and it was recently shown that it may be a ligand for the peroxisome proliferating activated receptor (PPAR) a. As administration of the 3-thia fatty acids seem to force EPA to the mitochondria, an additional fish oil effect might be seen. 

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