title: Effects of d-α-tocopherol supplements on lipid metabolism in a high-fat diet-fed animal model.
abstract: High-fat diet up-regulates either insulin resistance or triglycerides, which is assumed to be related to the expression of peroxisome proliferator-activated receptor (PPAR)-α and PPAR-γ. The beneficial effects of vitamin E on insulin resistance are well known; however, it is not clear if vitamin E with a high-fat diet alters the expression of PPAR-α and PPAR-γ. We investigated the effects of d-α-tocopherol supplementation on insulin sensitivity, blood lipid profiles, lipid peroxidation, and the expression of PPAR-α and PPAR-γ in a high-fat (HF) diet-fed male C57BL/6J model of insulin resistance. The animals were given a regular diet (CON; 10% fat), a HF diet containing 45% fat, or a HF diet plus d-α-tocopherol (HF-E) for a period of 20 weeks. The results showed that the HF diet induced insulin resistance and altered the lipid profile, specifically the triglyceride (TG) and total cholesterol (TC) levels (P < 0.05). In this animal model, supplementation with d-α-tocopherol improved insulin resistance as well as the serum levels of TG and very-low-density lipoprotein-cholesterol (VLDL-C) (P < 0.05). Moreover, the treatment decreased the levels of malondialdehyde (MDA) in the serum and liver while increasing hepatic PPAR-α expression and decreasing PPAR-γ expression. In conclusion, the oral administration of d-α-tocopherol with a high-fat diet had positive effects on insulin resistance, lipid profiles, and oxidative stress through the expression of PPAR-α and PPAR-γ in a high-fat diet-fed male mice.
authors.affiliation: Department of Medical Nutrition, Graduate School of East-West Medical Science, Kyung Hee University, 1732 Deogyeong-daero, Giheung-gu, Yongin, Gyeonggi 446-701, Korea. ; Research Institute of Medical Nutrition, Kyung Hee University, Seoul 130-701, Korea.
authors.forename: Do Yeon
authors.initials: DY
authors.lastname: Kim
authors.affiliation: Department of Medical Nutrition, Graduate School of East-West Medical Science, Kyung Hee University, 1732 Deogyeong-daero, Giheung-gu, Yongin, Gyeonggi 446-701, Korea.
authors.forename: Jinkyung
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Medical Nutrition, Graduate School of East-West Medical Science, Kyung Hee University, 1732 Deogyeong-daero, Giheung-gu, Yongin, Gyeonggi 446-701, Korea.
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Ham
authors.affiliation: Department of Medical Nutrition, Graduate School of East-West Medical Science, Kyung Hee University, 1732 Deogyeong-daero, Giheung-gu, Yongin, Gyeonggi 446-701, Korea. ; Research Institute of Medical Nutrition, Kyung Hee University, Seoul 130-701, Korea.
authors.forename: Ryowon
authors.initials: R
authors.lastname: Choue
keywords: High fat diet; d-α-tocopherol; insulin resistance; supplementation