[Effect of tea polyphenols on expression of nuclear factor kappa B].
OBJECTIVE
To investigate the effect of tea polyphenols (TP) on expression of nuclear factor kappa B (NF-kB) in rats with alcoholic liver diseases and in cells treated with alcohol.


METHODS
22 female Wistar rats were randomly divided into three groups: a control group, an alcohol model group and a TP plus alcohol group. All treatments were injected into stomach through intragastric tube. L02 cells were divided into five groups: a control group, an alcohol treated group, a prevention group (cells were treated with TP for 3 days, and then treated with alcohol), an intervention group (cells treated with TP and alcohol), and a therapeutic group (cells were treated with alcohol for 3 days, and then treated with TP). Histopathology was observed under light microscope (LM); serum MDA, ROS in cells were quantified by optical density measurement; the expression of NF-kB and IkB was determined by RT-PCR; and the activity of NF-kB was checked with Electrophoretic Mobility Shift Assay (EMSA).


RESULTS
LM indicated hepatocytes were injured obviously in the model group. Serum MDA and cells ROS in TP treated groups were significantly lower than the alcohol treated group. The level of NF-kB mRNA expression in TP treated groups(rats: 0.58+/-0.16, cells: 0.60+/-0.03, 0.59+/-0.01, 0.59+/-0.01) were significantly lower than the alcohol treated group (rats: 1.15+/-0.03, cells: 0.76+/-0.03) (P<0.01), the level of IkB mRNA expression in the prevention group, intervention group, and therapeutic group (0.51+/-0.01, 0.50+/-0.01, 0.50+/-0.12) were significantly higher than the alcohol treated group (0.61+/-0.03) (P<0.05), the difference among the three groups was not significant (P>0.05). The activity of NF-kB in TP treated rats(DNA stain: 669.85+/-41.34, Protein stain: 675.35+/-18.27) was significantly lower than the alcohol treated rats(DNA stain: 1410.78+/-22.19, Protein stain:1426.08+/-33.15) (P<0.01); NF-kB activity in cells of the prevention, intervention, therapeutic groups (DNA stain: 713.07+/-11.91, 710.79+/-14.99, 693.45+/-71.69; Protein stain: 758.88+/-34.65, 753.07+/-76.78, 725.77+/-36.09) was significantly lower than the alcohol treated cells (DNA stain: 849.94+/-12.45, Protein stain: 925.96+/-5.78) (P<0.01), the difference among the three TP treated groups was not significant (P>0.01).


CONCLUSIONS
TP can alleviate and prevent alcohol-induced liver injury via inhibiting NF-kB activation.
Tang
Yuan-ting
YT
Department of Pathology, College of Basic Medicine, Chongqing Medical University, Chongqing, 400016, China.
Guan
Xiao-qin
XQ
Liu
Li
L
Liu
Lin
L
Wang
Li-juan
LJ
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D002478:Cells, Cultured; D000431:Ethanol; D005260:Female; D022781:Hepatocytes / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D008108:Liver Diseases, Alcoholic / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D008315:Malondialdehyde / Q000097:blood; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism*; D010636:Phenols / Q000494:pharmacology*; D016133:Polymerase Chain Reaction; D020011:Protective Agents / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013662:Tea / Q000737:chemistry*
D000975:Antioxidants; D016328:NF-kappa B; D010636:Phenols; D020011:Protective Agents; D012333:RNA, Messenger; D013662:Tea; D000431:Ethanol; D008315:Malondialdehyde