[Recombinant human bone morphogenetic protein 7 inhibits the proliferation and extracellular matrix secretion of fibroblast of urethral scars].

Objective: To study the effect and its mechanism of recombinant human bone morphogenetic protein 7 (rhBMP-7) on urethral keloid fibroblast. Methods: Urethral fibroblasts were extracted and cultured, and the fourth-generation fibroblasts were used for experiment. Urethral fibroblasts were treated with rhBMP-7. Proliferation rate was detected by CCK-8 method. RT-PCR was applied to test changes of mRNA in α smooth muscle actin (α-SMA) and type Ⅰ collagen protein (COL-1) of each group. Western blot was used to measure α-SMA protein expression and the effect of rhBMP-7 on signaling pathway of urethral keloid fibroblasts. Results: With the increase of rhBMP-7 concentrations, the proliferation rate of urethral keloid fibroblast was generally decreased. Cells kept proliferating with time at the same concentration of rhBMP-7. mRNA level of COL-1 and α-SMA in rhBMP-7-treated (>20 ng/ml) urethral keloid fibroblasts was greatly reduced with statistical significance (P<0.05) and dose dependency. It was found rhBMP-7 inhibited the overexpression of p-smad2/3 and α-SMA mediated by transforming growth factor beta 1 (TGF-β(1)) signaling pathway. Conclusion: rhBMP-7 could adjust TGF-β(1) signaling pathway to inhibit gene expression of COL-1 and a-SMA in urethral keloid fibroblast, which provided evidences for further animal experiments or clinical trials.