Lipids

, Volume 47, Issue 5, pp 471–481

Tocotrienol Attenuates Triglyceride Accumulation in HepG2 Cells and F344 Rats

  • Gregor Carpentero Burdeos
  • Kiyotaka Nakagawa
  • Fumiko Kimura
  • Teruo Miyazawa
Original Article

DOI: 10.1007/s11745-012-3659-0

Cite this article as:
Burdeos, G.C., Nakagawa, K., Kimura, F. et al. Lipids (2012) 47: 471. doi:10.1007/s11745-012-3659-0

Abstract

Tocotrienol (T3) is an important phytonutrient found in rice bran and palm oil. T3 has gained much interest for lipid lowering effects, especially for cholesterol (Cho) by inhibiting 3-hydroxy-3-methylglutaryl-coenzyme A reductase. Also, usefulness of T3 in improving triglyceride (TG) profiles has been suggested, but its efficacy and mechanism have been unclear. We investigated how T3 decreases TG concentration in cultured cells and animals. In a cell culture study, human hepatoma cells (HepG2) were incubated in a control or a fat (1 mM oleic acid)-loaded medium containing γ-T3 for 24 h. We found that 10–15 μM γ-T3 inhibited cellular TG accumulation significantly, especially in the fat-loaded medium. This manifestation was supported by mRNA and protein expressions of fatty acid synthase, carnitine palmitoyltransferase 1, and cytochrome P450 3A4. In concordance with these results, rice bran T3 supplementation to F344 rats (5 or 10 mg T3/day/rat) receiving a high fat diet for 3 weeks significantly reduced TG and the oxidative stress marker (phospholipid hydroperoxides, PLOOH) in the liver and blood plasma. T3 supplementation did not show changes in the Cho level. These results provided new information and the mechanism of the TG-lowering effect of T3. The lipid lowering effects of dietary T3 might be mediated by the reduction of TG synthesis.

Keywords

Fatty acid synthase Tocotrienol Triglyceride β-Oxidation Antioxidant 

Abbreviations

BSA

Bovine serum albumin

CL

Chemiluminescence

Cho

Cholesterol

CPT1A

Carnitine palmitoyltransferase 1

CYP3A4

Cytochrome P450 3A4

FASN

Fatty acid synthase

FBS

Fetal bovine serum

HepG2

Human hepatoma cells

HMG-CoAR

3-Hydroxy-3-methylglutaryl-coenzyme A reductase

PCOOH

Phosphatidylcholine hydroperoxide

PEOOH

Phosphatidylethanolamine hydroperoxide

PL

Phospholipid

PLOOH

Phospholipid hydroperoxides

RBT3

Rice bran tocotrienol

RT-PCR

Real-time quantitative reverse transcription-PCR

T-Cho

Total cholesterol

TG

Triglyceride

Toc

Tocopherol

T3

Tocotrienol

Supplementary material

11745_2012_3659_MOESM1_ESM.pdf (61 kb)
Supplementary material 1 (PDF 61 kb)

Copyright information

© AOCS 2012

Authors and Affiliations

  • Gregor Carpentero Burdeos
    • 1
  • Kiyotaka Nakagawa
    • 1
  • Fumiko Kimura
    • 1
  • Teruo Miyazawa
    • 1
  1. 1.Food and Biodynamic Chemistry Laboratory, Graduate School of Agricultural ScienceTohoku UniversitySendaiJapan

Personalised recommendations