[Molecular mechanism of berberine in improving insulin resistance induced by free fatty acid through inhibiting nuclear trascription factor-kappaB p65 in 3T3-L1 adipocytes].
OBJECTIVE
To investigate the effect of berberine on nuclear transcription factor kappaB (NF-kappaB p65) expression and translocation in insulin resistant 3T3-L1 adipocytes induced by free fatty acid (FFA) and its possible molecular mechanism.


METHODS
3T3-L1 adipocytes were treated with palmic acid (0.5 mmol/L) to induce insulin resistance and intervened with berberine. Controlled with aspirin, the glucose consumption in the medium was determined by glucose oxidase method; glucose transportation by 2-deoxy-[3H]-D-glucose method; protein expression of NF-kappaB p65 in adopocytes by Western blot; and the distribution of NF-kappaB p65 was displayed by confocal laser scanning microscope (CLSM).


RESULTS
Treatment with 0.5 mmol/L of palmic acid for 24 h made glucose consumption of 3T3-L1 adipocytes decrease by 41%; the insulin-stimulated glucose transportation inhibited by 67%; nuclear NF-kappaB p65 protein expression and nuclear translocation of NF-kappaB p65 significantly increased. These changes were reversed by prior treatment with berberine or aspirin. But total NF-kappaB p65 protein expression was not responded to palmic acid, berberine and aspirin.


CONCLUSIONS
Berberine significantly improve the insulin resistance induced by FFA in 3T3-L1 adipocytes, its molecular mechanism might through inhibiting the activation and translocation related gene expression of NF-kappaB.
Yi
Ping
P
Department of Integrated Traditional Chinese and Western Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan.
Lu
Fu-Er
FE
Chen
Guang
G
D041721:3T3-L1 Cells; D017667:Adipocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D000818:Animals; D001599:Berberine / Q000494:pharmacology*; D015153:Blotting, Western; D005230:Fatty Acids, Nonesterified / Q000494:pharmacology*; D005947:Glucose / Q000378:metabolism / Q000493:pharmacokinetics; D007328:Insulin / Q000494:pharmacology; D007333:Insulin Resistance; D051379:Mice; D018613:Microscopy, Confocal; D051996:Transcription Factor RelA / Q000378:metabolism*
D005230:Fatty Acids, Nonesterified; D007328:Insulin; D051996:Transcription Factor RelA; D001599:Berberine; D005947:Glucose