Abstract
Vitamin E has an important role for prevention against lipid peroxidation in several pathological conditions. α-Tocopherol transfer protein (α-TTP) binds selectively α-tocopherol, and regulates α-tocopherol levels in the plasma. Moreover, α-TTP is known to play a critical role in the maintenance of pregnancy and in protecting against lipid peroxidation in the central nervous system. However, there are few reports regarding the regulation of α-TTP expression. We have conducted the promoter analysis of human α-TTP gene, and have examined vitamin E status and α-TTP expression in several pathological conditions including type 2 diabetes and nonalcoholic fatty liver disease (NAFLD). Human α-TTP gene is transcriptionally regulated through liver X receptor (LXR) signaling, which is a member of nuclear receptor superfamily and modulates lipid metabolism and energy metabolism. Hepatic α-TTP expression was altered in pathological conditions including type 2 diabetes and NAFLD, and might affect α-tocopherol status. Investigation of the regulation of α-TTP expression may contribute to further clarification of vitamin E status in pathological conditions and further understanding of the antioxidant mechanisms of vitamin E.
