Abstract： Objective To investigate the effect of berberine on glucose absorption and mRNA expression of 11 β-hydroxysteroid dehydrogenase type 1 ( 11β-HSD1 ) in insulin-resistant HepG2 cell model.Methods HepG2 cells were incubated with high-concentration insulin for 24 hours to build insulin-resistant cell model.In order to evaluate the cells for insulin resistance,the cells were cultured with different concentrations of insulin for 24 hours.The insulin-resistant cells were treated with different concentrations of berberine and insulin for 24 hours and the non insulin-resistant cells were used as a control.The glucose concentration in culture medium was detected by the method of glucose oxidase-peroxidase (GOD-POD).According to the glucose concentrations in blank medium and those in the medium of culturing cells 24 hours later,the rate of absorpting glucose by the cells was calculated.The mRNA expression of 11β-HSD1 in the insulin-resistant cells was detected by the reverse transcription polymerase chain reaction (RT-PCR).Results Incubated with 10-7mol/L insulin for 24 h,the insulin-resistant cell model had been built.The rate of glucose absorption of the model cell treated with high concentration berberine ( 10 μmol/L) was significantly improved [(42.53 ±1.99)％ vs (28.16±1.99)％,t =12.9457,P ＜0.01].High-concentration berberine showed a strong synergy with insulin on glucose absorption of the model cells.As the cells became resistant to insulin,the mRNA expression of 11β-HSD1 increased significantly compared to non insulin-resistant cells( relative expression quantity was (4.60 ±0.96 vs 0.67 ±0.42,t =4.9476,P ＜0.05 ).While the mRNA expression of 11β-HSD1 reduced in the insulin-resistant cells after treated with high-concentration berberine,and the relative expression quantity was not significantly different with non insulin-resistant cells ( 1.12 ±0.35 vs 0.67 ±0.42,P ＞0.05).However,low-concentration ( 1 μmol/L) of berberine had not the same role.Conclusions It is concluded that one of the acting mechanism of berberine improving the insulin sensitivity may be that the mRNA expression of 11β-HSD1 is downregulated in the insulin-resist-ant liver cell model depending on concentration.