Evidence that the trans-10,cis-12 isomer of conjugated linoleic acid induces body composition changes in mice

We investigated the effects of conjugated linoleic acid (CLA) preparations, which were enriched for the cis-9, trans-11 CLA isomer or the trans-10,cis -12 CLA isomer, on body composition in mice. Body composition changes (redu ced body fat, enhanced body water, enhanced body protein, and enhanced body ash) were associated with feeding the trans-10,cis-12 CLA isomer. In cultu red 3T3-L1 adipocytes, the trans-10,cis-12 isomer reduced lipoprotein lipas e activity, intracellular triacylglycerol and glycerol, and enhanced glycer ol release into the medium. By contrast, the cis-9,trans-11 and trans-9,tra ns-11 CLA isomers did not affect these biochemical activities. We conclude that CLA-associated body composition change results from feeding the trans- 10, cis-12 isomer.