Objective To investigate the effect of rhGLP-1 on the expression of Akt, a key site of insulin signalling pathway in human hepatocyte line (HL-7702), in order to explore the mechanism by which rhGLP-1 regulates insulin signal pathway PI3K-AKT-mTORC in hepatocytes.Methods HL-7702 cells in the logarithmic growth phase were selected and divided into three treatment groups and one control group. The three treatment groups were respectively treated with different concentrations of rhGLP-1 (7-36) (10, 100, 1000nM) for 24 hours, while the control group was cultured for 24 hours with an equal amount of medium. The expression of Akt protein and its phosphorylation level were detected by Western blot.Results The expression of Akt did not change significantly in any group. so were the levels of phosphorylation of Akt (Ser473). The levels of phosphorylation of Akt (Thr308) in 10 nM treatment group(0.60±0.27 vs 1±0,P<0.05), in 100nM treatment group(0.54±0.15 vs 1±0,P<0.01), and in 1000 nM treatment group(0.61±0.18 vs 1±0,P<0.05)were all significantly lower than that in the control group.Conclusions The decrease of the expression of phosphorylated Akt in rhGLP-1 treated HL-7702 cells indicates that GLP-1 may have inhibitory effect on PI3K-AKT-mTORC pathway, which may be one of the mechanisms by which GLP-1 reduces blood lipids.
Key words
rhGLP-1 /
hepatocyte /
insulin signalling pathway
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