Researchers at the University of Wisconsin-Madison have discovered that a fatty acid found in cows' milk is a natural regulator of the cyclooxygenase 2 (COX-2) protein, which plays a significant role in inflammatory diseases such as arthritis. This acid, called conjugated linoleic acid (CLA), "prevents inflammatory damage resulting from immune response," according to Mark Cook, PhD, a professor of animal science at the university's College of Agricultural and Life Sciences.
Although the amount of the anti-inflammatory isomer of CLA in milk is small in comparison with the amount of other fatty acids, there may still be enough to produce a positive effect in a patient who consumes dairy products daily. Dr. Cook's team is planning a study to determine whether the amount of CLA in milk can be increased by changing the diets of dairy cows.
CLA, which is synthesized by microbial fermentation in the rumen of dairy cows, exists naturally in different forms. Dr. Cook's team found that one of the forms inhibits the COX-2 protein by blocking a key cellular pathway. COX-2 is an important target of many drugs used to treat arthritis, said Dr. Cook.