ABSTRACT
Objective To investigate the expression of Paxillin (Pax) in human kidney proximal tubular epithelial cell line (HKC) induced by transforming growth factor ?1(TGF?1). Methods HKC cells cultured in vitro were divided into three groups at random: control group(C): cultured with free serum medium(FSM), TGF?1-treated groups (T1 and T2): cultured with FSM containing different concentrations of TGF?1 (T1: 5 ng/ml, T2: 10 ng/ml). After 48-hour treatment, the expression of Pax mRNA and protein was detected by reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemical staining in HKC cells respectively. Results In Group C, the expression of Pax mRNA and protein in HKC cells was elementary. However, in T1 and T2 groups , the expression of Pax mRNA and protein in HKC cells was greatly increased, especially in T2 group which was more significantly increased than T1 group (P
ABSTRACT
Objective To investigate the effect of activated PI3-K on epithelial-mesenchymal transdifferentiation of HKCs induced by transforming growth factor?1 (TGF-?1). Methods The human kidney proximal tubular epithelial cells (HKCs) cultured on plastic plates were divided into following groups: cultured with free serum medium (FSM); culture in the different concentrations of TGF-?1; cultured in the presence of recombinant human TGF-?1 and PI3-K inhibitor Wortmannin. The expression of total and phosphor-Akt (t-Akt and p-Akt) was assessed at different time points by Western blot,? smooth muscle actin(?-SMA) and E-cadherin were detected by Western blot. Results A marked increase in p-Akt was seen in HKC at 1h after being induced by TGF-?1, and its protein level was enhanced in a TGF-?1 concentration-dependent manner. Protein level of ?-SMA was increased markedly at 48 hours after the treatment of TGF-?1, but protein level of E-cadherin was decreased 48 hours after treatment of TGF-?1. Addition of PI3-K inhibitor Wortmannin (10nmol/L) largely abrogated the effect of TGF-?1. Wortmannin was showed to down-regulate ?-SMA and p-Akt expression and in response to TGF-?1 and up-regulate E-cadherin expression. Conclusion PI3-K was activated in epithelial-mesenchymal trans-differentiation of HKCs promoted by TGF-?1, and PI3-K inhibitor Wortmannin can significantly inhibit TGF-?1 induction of EMT.