Research On The Co-modulation Effects Of Integrin And Voltage-dependent Ca2+ Channels On The Transition Of Tubular Epithelial To Myofibroblast

Objective Using transforming growth factor(TGF-β1) to induce the tubular epithelial to myofibroblast transdifferentiation(EMT) of HK-2 so as to explore the possible mechanism of molecular signal transduction during the EMT process; to explore the effect of SA-B on the transition of tubular epithelial to myofibroblast.Methods HK-2 were stimulated with TGF-β1, and then were handled with PD98059(25μmol/L),Nifedipine(10μmolol/L)and salvianolic acid-B(SA-B). Considering the E-Cadherin andα-SMA as the indicator of EMT, and using immunohistochemistry and Western-blot to observe the expression of FAK and phospho-FAK(Tyr397) and immunoflourescence for that of the Integrin-β1Results1. Compared with the control group, the expression of E-Cadherin mRNA decreased gradually while theα-SMA mRNA increased in the TGF-β1 group;2. The phosphorylation effects of FAK-Tyr397 enhanced after 15min of the TGF-β1 stimulation, and it reached to a peak after 60min. Contrasted to the TGF-β1 group, PD98059 reduced the phosphorylation effects of FAK-Tyr397(P<0.05)while Nifedipine didn't show obvious inhibitor effect on it(P>0.05), PD98059 and Nifedipine had synergistic effects for the phosphorylation level(P<0.01),as well SA-B(P<0.01);3. Contrasted to the TGF-β1 group, PD98059 caused a time-dependent reduction of the expression of FAK protein(P<0.05), while Nifedipine didn't show obvious inhibitor effect on it(P>0.05), and they had synergistic effects (P<0.01). SA-B caused a time-dependent reduction of the expression of FAK protein as well(P<0.01);4. Both of PD98059 and Nifedipine had a time-dependent inhibiting effects on theβ1-Integrin's expression(P<0.05), and their synergistic effect was much stronger(P<0.01);SA-B also has a strong effects on theβ1-Integrin's expression(P<0.01)Conclusions During the transition process of tubular epithelial to myofibroblast, The signal transduction between TGF-β1 and Integrin interacted through ERK/FAK, calcium channels co-modulated the activation of FAK as well as the expression of FAK andβ1-Integrin. SA-B has effects on the EMT process of HK-2 through such these signal transduction ways.