摘要
目的研究壳聚糖在朋．腱损伤修复术后抑制成纤维细胞生长的分子机制。方法对跟腱损伤大鼠在术中给予壳聚糖处理，8周后检测肌腱滑动距离和总胶原含量。同时分离修复后肌腱组织中的成纤维细胞，给予不同浓度壳聚糖处理，检测细胞成活率、凋亡和细胞周期。此外，RT-PCR检测肌腱组织和成纤维细胞中miRNAs，Westernblot检测TGF-β1、Smad3和P21蛋白的表达。结果壳聚糖可以增加大鼠术后肌腱滑动距离并降低胶原纤维的含量，抑制成纤维细胞生长并使其停留在生长周期的G1期。此外，在修复后的肌腱组织和体外成纤维细胞中均发现壳聚糖显著上调miR-29b的表达，同时显著增加P21蛋白表达，而下调TGF-β1和Smad3的蛋白表达。在成纤维细胞中，miR-29b抑制剂可逆转壳聚糖引起miR-29b、TGF-β1、Smad3和P21表达的改变。结论壳聚糖能促进大鼠跟腱损伤术后的肌腱修复，miR-29b通过下调TG-β1、Smad3、上调P21表达促使成纤维细胞停留在G1期，这可能是壳聚糖在修复损伤肌腱过程中发挥积极作用的机制之一。
Objective To study the molecular mechanism of chitosan inhibiting fibroblast growth after tendon repair. Methods The rats with Achilles tendon injury were treated with chitosan during operation, and the sliding distance and total collagen content were examined 8 weeks postoperatively. Simultaneously, the fibroblasts in the repaired tendon tissue were separated and treated with different concentrations of chitosan. The survival rate, apoptosis and cell cycle of the cells were examined. In addition, the expression of miRNAs was quantifed by real-time PCR and expression of TGF-131, Smad3 and P21were quantified by westem blot. Results Chitosan can increase the tendon gliding distance, reduce the content of collagen fibers, inhibit the growth of fibroblasts and arrest cells in G1 phase of the growth cycle. Chitosan also up-regulated the expression of miR-29b and P21 but down-regulated the levels of TGF-I3t and Smad3 in repaired tendon tissue and in vitro fibroblasts. In fibroblasts, miR-29b inhibitor can reverse the expression changes ofmiR-29b, TGF-131, Smad3 and P21 induced by chitosan. Conclusion Chitosan can promote the repair of Achilles tendon injury in rats. miR-29b causes fibroblasts staying at G1 phase by down-regulating the expression of TGF-β1 and Smad3 and up-regulating the expression of P21. It mav be one of the mechanisms of chitosan plaving a positive role in the process of tendon repair.
出处
《中华手外科杂志》
CSCD
北大核心
2017年第6期464-467,共4页
Chinese Journal of Hand Surgery
基金
浙江省医药卫生科技项目资助（2016KYB093）
浙江省中医药科学研究基金项目（2016ZAl24）
