European Journal of Scientific Research (ISSN: 1450 ... - EuroJournals

© European Journal of Scientific Research, Vol 7, No 5, 2005
CYP4F2 also proved to be involved in vitamin E metabolisme (28). But the degradation
activity of vitamin E by CYP2E1 is yet to be confirmed.
There are other study that reported vitamin E activated pregnane X receptor (PXR) which
involved in CYP P450 genes regulation. γ-Tocotrienol is the form that binds effectively
to the receptor (29). Enhanced activity of CYP2E1 through PXR may results in enhanced
lipid peroxidation, thus reduce the effect of γ-tocotrienol in E47 cells.
CONCLUSION
Hep G2 cells that express human CYP2E1 enzyme showed higher lipid peroxidation after
ethanol induction. α-Tocopherol (ATF) and γ-tocotrienol (GTT) reduced the level of lipid
peroxidation in Hep G2 cell line (C34 cells). However in Hep G2 cell line transfected
with CYP2E1 gene (E47 cells), only α-tocopherol treatment at 150, 200 and 300 µM
reduced the level of lipid peroxidation but γ-tocotrienol treatment did not show
significant effect. Thus we concluded that the presence of CYP2E1 gene affects the level
of lipid peroxidation with ethanol induction and vitamin E treatment protects against lipid
peroxidation with α-tocopherol possessed higher antioxidant activity.
ACKNOWLEDGEMENTS
We would like to thank Prof. A.I. Cederbaum from Mount Sinai School of Medicine,
New York for kindly providing the E47 and C34 cell lines and Mr. Gapor Md. Top for
providing the palm oil vitamin E isomers.
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