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

© European Journal of Scientific Research, Vol 7, No 5, 2005
COMPARATIVE EFFECTS OF α-TOCOPHEROL AND γ-TOCOTRIENOL ON
LIPID PEROXIDATION STATUS IN HEP G2 CELL LINE TRANSFECTED
WITH CYP2E1 GENE
Suzana Makpol a (PhD), Suhana Mamat a (BSc), Zalinah Ahmad a (PhD), Gapor Md. Top b
(MSc) and Wan Zurinah Wan Ngah a (PhD)
a
Department of Biochemistry, Faculty of Medicine, Universiti Kebangsaan Malaysia,
Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Malaysia and b Dept. of Chemistry,
Malaysian Palm Oil Board, 43500 Bangi, Selangor, Malaysia.
ABSTRACT
Hepatic cytochrome P450 2E1 (CYP2E1) is a xenobiotic-metabolizing enzyme which is
ethanol-inducible and actives in catalyzing lipid peroxidation than several other forms of
cytochrome P450 enzymes. Vitamin E is well known for its antioxidative properties
which protects against oxidative damage in cells. The objective of the study is to
investigate the effect of palm oil vitamin E on lipid peroxidation status in Hep G2 cells
transfected with CYP2E1 gene. Two cell lines were used as study model ie. E47
(transfected Hep G2 cell line that expresses human CYP2E1) and C34 (Hep G2 cell line
which does not express CYP2E1 enzyme) as control. Both cells were treated with 75 µM
ethanol and palm oil α-tocopherol and γ-tocotrienol. Five doses of α-tocopherol and γtocotrienol
ie. 50, 100, 150, 200 and 300 µM were used. Lipid peroxidation status was
determined by measuring the level of total malondialdehyde (MDA) and 4hydroxynonenal
(4HNE) using lipid peroxidation assay kit. Results showed that in C34
cells, ethanol did not cause any changes to the status of lipid peroxidation in the cells.
However in E47 cells, the status of lipid peroxidation was significantly higher (p