[Effects of tea polyphenols and tea pigments on apoptosis in HepG2 cell line].
OBJECTIVE
To investigate the effect of tea polyphenols and tea pigments on apoptosis in HepG2 cells.


METHODS
HepG2 cells were seeded at a density of 5 x 10(5)/well in six-well culture dishes. The cells were then treated with 50 or 100 mg/L tea pigments and harvested at 48h by trypsinization. Agrose electrophoresis was applied to investigate DNA-LADDER, Bcl-2 and Bax protein expression were detected by Western blot.


RESULTS
Tea polyphenols and tea pigments induced the appearance of DNA-LADDER; Western blot analysis demonstrated that Bcl-2 expression was significantly inhibited and the expression of Bax was significantly induced by tea polyphenols and tea pigments.


CONCLUSIONS
Induction of apoptosis may be an important mechanism of cancer chemoprevention by tea.
Jia
Xu-Dong
XD
Institute of Nutrition and Food Safety, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
Han
Chi
C
Chen
Jun-Shi
JS
D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D006528:Carcinoma, Hepatocellular / Q000473:pathology; D045744:Cell Line, Tumor; D005419:Flavonoids / Q000494:pharmacology*; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology*; D010636:Phenols / Q000494:pharmacology*; D010860:Pigments, Biological / Q000494:pharmacology*; D059808:Polyphenols; D013662:Tea / Q000737:chemistry
D000972:Antineoplastic Agents, Phytogenic; D005419:Flavonoids; D010636:Phenols; D010860:Pigments, Biological; D059808:Polyphenols; D013662:Tea