University of Wisconsin-Madison researchers have discovered that one of the isomers in conjugated linoleic acid is a natural regulator of the COX-2 protein which plays a significant role in inflammatory disease such as arthritis and cancer.

"It's clear from previous research that conjugated linoleic acid, or CLA, prevents inflammatory damage resulting from immune response," says Mark Cook, a professor of animal science in UW-Madison's College of Agricultural and Life Sciences.  "We've identified the biochemical mechanism by which this occurs."

CLA, which is synthesized by microbial fermentation in the rumen of dairy cows, exists naturally in a number of structural forms. Cook's team determined that one of the variants inhibits the COX-2 protein by blocking a key cellular pathway.  The COX-2 protein is known to play a significant role in many inflammatory diseases and is an important drug target for treating arthritis and cancer, Cook says.

While the amount of the anti-inflammatory isomer of CLA in milk is small relative to other fatty acids in milk, there may still be enough to elicit an effect if someone consumes dairy products every day, says Cook.  He is planning a study, in collaboration with researchers in the dairy science and food science departments, to determine whether the amount of anti-inflammatory CLA in milk can be increased by changing dairy cow diets.

The work was funded by a Thomsen Wisconsin Distinguished Graduate Fellowship, the College of Agricultural and Life Sciences, the University of Wisconsin-Madison, the Wisconsin Alumni Research Foundation, and by BASF and Natural Lipids, Inc.

University of Wisconsin - Madison