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.
目的：研究重组人骨形态发生蛋白7( rhBMP-7)对尿道瘢痕成纤维细胞增殖、细胞外基质分泌的影响。 方法：用不同浓度的rhBMP-7处理由尿道瘢痕提取并培养至第4代的成纤维细胞；采用CCK-8法测定细胞增殖速率，并用逆转录聚合酶链式反应(RT-PCR)检测各组α-平滑肌肌动蛋白(α-SMA)及Ⅰ型胶原蛋白(COL-1) mRNA的变化；使用Western印迹测定α-SMA的表达及rhBMP-7对成纤维细胞信号通路的影响。 结果：同一时间点，随着rhBMP-7浓度增加，尿道瘢痕成纤维细胞增殖速率下降；高于20 ng/ml的rhBMP-7处理的成纤维细胞时，COL-1及α-SMA的mRNA显著降低，差异具有统计学意义(P<0.05)，并呈现剂量依赖性。Western印迹实验表明rhBMP-7能抑制转化生长因子-β1(TGF-β1)介导的p-smad2/3和a-SMA的过表达。 结论： rhBMP-7通过调节TGF-β1信号通路，可抑制尿道瘢痕成纤维细胞增殖及COL-1、α-SMA基因表达。.
Keywords: Bone Morphogenetic Protein 7; Fibroblasts; Keloid; Transforming Growth Factor beta1.