Bioactive LbL-assembled multilayer nanofilms upregulate tenogenesis and angiogenesis enabling robust healing of degenerative rotator cuff tendons in vivo
Bioactive LbL-assembled multilayer nanofilms upregulate tenogenesis and angiogenesis enabling robust healing of degenerative rotator cuff tendons in vivo
复制标题
生物活性 LbL 组装的多层纳米膜可上调肌腱生成和血管生成，从而实现体内退变肩袖肌腱的稳健愈合
DOI：
10.1039/c9bm00413k
复制
发表时间：
2019
影响因子：
6.6
通讯作者：
Peng Zhao
中科院分区：
文献类型：
--
作者：
Fei Han;Peng Zhang;Xuejun Wen;Chao Lin;Peng Zhao
肩袖肌腱的退行性变化通常在老年患者中被诊断出来。由于缺乏合适的微环境供肌腱干细胞分化和血管化，退化肌腱的自发愈合是相当低效的。本文中，通过逐层组装方法将多层透明质酸/壳聚糖（HA/CS）纳米膜组装到排列的聚（ε-己内酯）（PCL）纳米纤维上以用于愈合退行性肌腱。材料测试表明，HA/CS纳米膜的层数可以调节纳米纤维膜的亲水性和润湿性。在体外，最佳的8层（称为8LP）膜提供了对齐的肌腱干/祖细胞（TSPC）的形态和上调的肌腱标记物（SCX，BGN）的mRNA表达。在具有紊乱的肩袖肌腱的兔模型中，与天然PCL组相比，8LP组在术后6周而非12周上调胶原蛋白I/III和腱生蛋白（TNC）的mRNA水平。接着，制备负载血管内皮生长因子的8LP（称为8LP-V）。与8LP相比，8LP-V在术后6或12周在肌腱中产生更高水平的血管生成，从而提供内源性肌腱前生长因子（TGF-β，IGF-1）以进一步增强肌腱生成转录因子。因此，与8LP和临床心包补片组相比，8LP-V产生了更厚的胶原纤维和/或更高的肌腱刚度。本研究强调了LBL组装的多层HA/CS膜的合理设计，以上调肌腱生成，从而使退行性肩袖肌腱稳健愈合。
Degenerative changes to rotator cuff tendons are often diagnosed in elderly patients. Spontaneous healing of degenerative tendons is rather inefficient as a result of the lack of a suitable microenvironment for tendon stem cell differentiation and vascularization. Herein, multilayer hyaluronic acid/chitosan (HA/CS) nanofilms were assembled by a layer-by-layer assembly method onto aligned poly(ε-caprolactone) (PCL) nanofibers for use in healing degenerative tendons. Materials testing showed that the number of layers of HA/CS nanofilms could adjust the hydrophilicity and wettability of the nanofibrous membranes. In vitro, the optimal 8-layer (termed as 8LP) membrane afforded aligned morphology of tendon stem/progenitor cells (TSPCs) and up-regulated mRNA expression of tenogenic markers (SCX, BGN). In a rabbit model with disorganized rotator cuff tendons, the 8LP group up-regulated mRNA levels of collagen I/III and tenascin (TNC) at 6 weeks, but not 12 weeks, post-surgery as compared to the native PCL group. Next, vascular endothelial growth factor-loaded 8LP (termed as 8LP-V) was prepared. Compared to 8LP, 8LP-V produced higher levels of angiogenesis in the tendons at 6 or 12 weeks post-surgery, thus supplying endogenous pre-tendon growth factors (TGF-β, IGF-1) to further enhance tenogenic transcriptional factors. As a result, 8LP-V yielded thicker collagen fibers and/or higher tendon stiffness as compared to the 8LP and clinical pericardial patch groups. This study highlights the rational design of LbL-assembled multilayer HA/CS films to upregulate tenogenesis for robust healing of degenerative rotator cuff tendons.