Prevent And Revert Effects Of Immunosuppressants On Epithelial-to-mysenchymal Transtion And Glucocorticoid Resistance In Albumin Overloaded Human Renal Tubular Epithelial Cells

Objective:To investigate the possible effects of Dexamethasone (Dex),Methylpredisolone(MP) and Cyclosporine A(CsA) on epithelial-to-mysenchymal transition(EMT) and the expression of glucocorticoid resistance related factors,P-glyprotein(P-gp) and glucocorticoid receptor-β(GRβ),in the albumin overloaded human renal tubular epithelial cells(HKC).Methods:Two experiments were established in our study.①Prevent experiment:Coadministration of 20mg/ml HSA and 10^-4M Dex, 10^-4M MP,or 200ng/ml CsA on cultured HKC cells for 48 hours to prevent the overloaded HSA induced EMT,respectively.②Revert experiment:HKC were cultured in 20mg/ml HSA for 48 hours,then cocultured with 10^-4M Dex,10^-4M MP,or 200ng/ml CsA,respectively, for another 48 hours.The effects of Dex,MP and CsA on cell morphology and the expression of cytokeratin(CK),vimentin,P-gp and GRβwere studied by phase contrast microscopy and immunocytochemistry assay.Results:①20mg/ml HSA overload could induce HKC cells morphological alteration from ovoid to fusiform in shape,down-regulate expression of CK and up-regulate expression of vimentin,P-gp and GRβin HKC;②In prevent experiment,Dex or MP could prevent HKC cells morphologic alteration,but CsA could promote HKC cells morphologic change induced by HSA overload;Dex or MP could prevent the up-regulated expression of vimentin and down-regulated expression of CK induced by HSA overload markedly;CsA has similar effect but without significatively statistical difference(P＞0.05);Dex and MP could increase the expression of P-gp and GR-βin HSA overload HKC cells, while CsA could inhibit the expression of P-gp and GR-βin HSA overload HKC cells;③In revert experiment,Dex,MP or CsA could help HKC cells to recover from the morphologic alteration,and revert the up-regulated expression of vimentin and down-regulated expression of CK induced by HSA overload.Dex or MP could further promote the increased expression of P-gp and GRβinduced by HSA overload,while CsA could inhibit the increased expression of P-gp and GRβinduced by HSA overload.Conclusion:①Albumin overload could induce HKC cells to EMT.②Dex or MP could either prevent or revert EMT of HKC induced by HSA overload;CsA could only revert EMT of HKC induced by HSA overload.③Dex or MP could neither prevent nor revert the higher expression of P-gp and GRβinduced by HSA overload in HKC,while CsA could prevent and revert the higher expression of P-gp and GRβinduced by HSA overload.