Tocotrienol enriched palm oil prevents atherosclerosis through modulating the activities of peroxisome proliferators-activated receptors

Palm oil is enriched in vitamin E in the form of alpha-, gamma-, and delta-tocotrienols. Dietary tocotrienol supplements have been shown to prevent atherosclerosis development in patients and preclinical animal models. However, the mechanistic basis for this health beneficial effect is not well established. Peroxisome proliferator-activated receptors alpha, gamma, and delta (PPAR alpha, PPAR gamma, and PPAR delta) are ligand regulated transcription factors that play essential preventive roles in the development of atherosclerosis through regulating energy metabolism and inflammation. In this study, we presented data that the tocotrienol rich fraction (TRF) of palm oil activated PPAR alpha, PPAR gamma, and PPAR delta in reporter based assays. Importantly, TRF attenuated the development of atherosclerosis in ApoE(-/-) mice through inducing PPAR target gene liver X receptor alpha (LXR alpha) and its down-stream target genes apolipoproteins and cholesterol transporters, suggesting that modulating the activities of PPARs is a key aspect of the in vivo action of tocotrienols. (C) 2010 Elsevier Ireland Ltd. All rights reserved.