trans-10,cis-12 Conjugated linoleic acid specifically increases tissue α-tocopherol mediated by PPARγ inhibition in mice

C57BL/6J mice were divided into control group (C), CLA, c9t11, or t10c12 groups. CLA and t10c12 significantly increased α-tocopherol levels in the plasma and various tissues in experiment 1. The CLA and t10c12 groups also showed a significant increase in hepatic α-tocopherol transfer protein (α-TTP) levels. In experiment 2, mice were divided into control, CLA, R (rosiglitazone, a PPARγ agonist), or CLA+R groups. Vitamin E levels in the liver, epididymal fat pad, kidney, and plasma were increased by CLA, and this effect was reduced in the CLA+R group. t10,c12-CLA is the most active isomer in the CLA mixture in the regulation of tissue vitamin E status and α-TTP protein levels in mice. The increase in liver vitamin E status in CLA-fed mice is mainly due to the effect of PPARγ inhibition.