To Explore The Effects Of Glycyrrhetinic Acid And EGF On The Expression Of MiR-21/PDCD4 In HaCaT Cells

Objective To explore the effect of glycyrrhetinic acid and EGF on the expression of miR-21/PDCD4 in HaCaT cells and the relevance between the signaling pathways of miR-21/PDCD4 and the pathogenesis of psoriasis,To provide some experimental basis for glycyrrhetinic acid developing and appling in psoriasis in the future.Methods 1.MTT assay was used to determine the proliferation of HaCaT cells incubated with different concentrations of EGF(0,5,15,25,50ng/ml).The inhibition effects of 25μmol/L glycyrrhetinic acid on the proliferation of HaCaT cells induced by 25ng/ml EGF were also tested with MTT assay.2.Western-blot was used to determine the protein expression of PDCD4 of HaCaT cells incubated with different concentrations of EGF.The effects of 25μmol/L glycyrrhetinic acid on the protein expression of PDCD4 of HaCaT cells induced by 25ng/ml EGF were also tested with Western-blot.3.Real-timePCR was used to determine the expression of miR-21 of HaCaT cells incubated with different concentrations of EGF.The effects of 25 μmol/L glycyrrhetinic acid on the expression of miR-21 and PDCD4 mRNA of HaCaT cells induced by 25ng/ml EGF were also tested with Real-timePCR.Results 1.In the range of 0～50 ng/ml,EGF promoted the proliferation of HaCaT cells in a dose-dependent manner,25ng/ml EGF played a obvious effect on the proliferation of HaCaT cells,In the range of 0～50 ng/ml,the concentration of EGF was linearly correlated to the proliferation of HaCaT cells(r=0.91,P<0.05).Compared with the blank control group,25μmol/L glycyrrhetinic acid could significantly inhibit the proliferation of HaCaT cells(P<0.01),25μmol/L glycyrrhetinic acid could significantly inhibit the promoting proliferation of 25 ng/ml EGF in HaCaT cells(P<0.01).2.EGF inhibited the expression of PDCD4 with concentration dependence manner in HaCaT cell.25μmol/L glycyrrhetinic acid promoted the expression of PDCD4 and inhibite-d the effect of 25ng/ml EGF on inhibiting expression of PDCD4 in HaCaT cell.3.EGF promoted the expression level of miR-21 with concentration dependence manner in HaCaT cell.25μmol/L glycyrrhetinic acid inhibited the expression of miR-21 and inhibited the effect of 25ng/ml EGF on stimulating expression of miR-21 in HaCaT cell.4.Compared with the blank control group,25ng/ml EGF inhibited the expression level of PDCD4 mRNA and 25μmol/L glycyrrhetinic acid promoted the expression level of PDCD4 mRNA in HaCaT cells,25μmol/L glycyrrhetinic acid inhibited the effect of 25ng/ml EGF on inhibited expression level of PDCD4 mRNA in HaCaT cells.Conclusion 1.EGF can down-regulate the expression level of PDCD4 by up-regulate the expression of miR-21 to promote the proliferation of HaCaT cell,Glycyrrhetinic acid can up-regulate the expression level of PDCD4mRAN by down-regulate the expression miR-21 to inhibite the proliferation of HaCaT cell.2.miR-21 can negatively regulate the expression of PDCD4 involved in the pathogenesis of psoriasis.Glycyrrhetinic acid can inhibit the proliferation of HaCaT cell by regulating the signaling pathways of miR-21/PDCD4.To provide some experimental basis for glycyrrhetic acid developing and appling in the treatment of psoriasis in the future.