Fig. 8.

Smad3 regulates TGF- β1 induced upregulation of CCN2, whereas upregulation of MMP-2 is Smad2 dependent, Smad2 and Smad3 both participate in MMP-9 reduction. Porcine bladder UC cells transfected with Smad2 and Smad3 siRNA and incubated for 24 h at 37 ° C. TGF-β1 was added to the culture and further incubated for 24 h. Cells were lysed and silencing of Smads were assessed by Western blotting. a TGF-β1 treatment for 24 h resulted in a significant increase in CTGF/CCN2 expression. Smad2 knockdown resulted in no significant decrease in TGF-β1 mediated CTGF/CCN2 expression (p < 0.01). b TGF-β1 treatment resulted in a significant increase in CTGF/CCN2 expression. Knock down of Smad3 resulted in about 90 % decrease in TGF-β1 mediated CCN2 expression (p < 0.01). c Silencing of Smad2 did cause significant downregulation of MMP-2 and treatment by TGF-β1 prevented the expression of MMP-2 (p < 0.01). d Silencing of Smad3 did not cause significant downregulation in MMP-2 expression. e and f Silencing of Smad2 and Smad3 caused partial abrogation of MMP-9, g Simultaneous knockdown of both Smad2 and Smad3 significantly abrogated MMP-9 expression. Non-targeting scrambled siRNA did not show any effects on CTGF/CCN2, MMP-2 and MMP-9 expression