| Objective To explore the effect and mechanism of glycyrrhetinic acid on proliferation of HaCaT cells induced by epidermal growth factor (EGF) and lay an experimental basis for glycyrrhetinic acid applied in the treatment of psoriasis.Methods MTT assay was used to determine the proliferation of HaCaT cells incubated with different concentrations of EGF (0,1,5,10,25,50,100μg/L) and glycyrrhetinic acid (0,0.1,1.0,10,25,50,100μmol/L). The inhibition effects of25μmol/L glycyrrhetinic acid and10μmol/L MEK1/2inhibitor (U0126) on the proliferation of HaCaT cells induced by25μg/L EGF were also tested with MTT assay. Western-blot was applied to measure the protein expression of proliferating cell nuclear antigen (PCNA), Notch-1, ERK1/2and phospho-ERK1/2of HaCaT cells incubated with EGF, or added with25μmol/L glycyrrhetinic acid or10μmol/L U0126.Results In the range of0～100μg/L, EGF promoted the proliferation of HaCaT cells in a dose-dependent manner (r=0.798, P<0.05). In the range of0～50μg/L, the concentration of EGF was linearly correlated to the proliferation of HaCaT cells (r=0.859, P<0.05), while in the range of10-100μmol/L, glycyrrhetinic acid played an inhibition role in a dose-dependent manner (r=-0.945, P<0.01),10μmol/L glycyrrhetinic acid could inhibit the proliferation of HaCaT cells (P<0.01),25μmol/L glycyrrhetinic acid could further inhibit the proliferation of HaCaT cells (P<0.01).25μmol/L glycyrrhetinic acid or10μmol/L U0126could effectively inhibit the rate of cell proliferation, phosphorylation of ERK1/2, PCNAand Notch-1expression induced by25μg/L EGF.Conclusion Glycyrrhetinic acid inhibits the proliferation of HaCaT cells induced by EGF, and the mechanism may be related to inhibit the activation of ERK1/2signaling pathway. |
