Quality of Indoor Environment, University Centre for Energy Efficient Buildings, Czech Technical University in Prague, Bustehrad, Czech Republic.
Department of Biophysics, Second Medical Faculty, Charles University in Prague, Prague, Czech Republic.
Int J Nanomedicine. 2022 Dec 14;17:6335-6345. doi: 10.2147/IJN.S364888. eCollection 2022.
A current topic of ma jor interest in regenerative medicine is the development of novel materials for accelerated healing of sutures, and nanofibers seem to be suitable materials for this purpose. As various studies have shown, nanofibers are able to partially substitute missing extracellular matrix and to stimulate cell proliferation and differentiation in sutures. Therefore, we tested nanofibrous membranes and cryogenically fractionalized nanofibers as potential materials for support of the healing of intestinal anastomoses in a rabbit model.
We compared cryogenically fractionalized chitosan and PVA nanofibers with chitosan and PVA nanofiber membranes designed for intestine anastomosis healing in a rabbit animal model. The anastomoses were biomechanically and histologically tested.
In strong contrast to nanofibrous membranes, the fractionalized nanofibers did show positive effects on the healing of intestinal anastomoses in rabbits. The fractionalized nanofibers were able to reach deep layers that are key to increased mechanical strength of the intestine. Moreover, fractionalized nanofibers led to the formation of collagen-rich 3D tissue significantly exceeding the healing effects of the 2D flat nanofiber membranes. In addition, the fractionalized chitosan nanofibers eliminated peritonitis, significantly stimulated anastomosis healing and led to a higher density of microvessels, in addition to a larger fraction of myofibroblasts and collagen type I and III. Biomechanical tests supported these histological findings.
We concluded that the fractionalized chitosan nanofibers led to accelerated healing for rabbit colorectal anastomoses by the targeted stimulation of collagen-producing cells in the intestine, the smooth muscle cells and the fibroblasts. We believe that the collagen-producing cells were stimulated both directly due to the presence of a biocompatible scaffold providing cell adhesion, and indirectly, by a proper stimulation of immunocytes in the suture.
再生医学领域的一个当前热门话题是开发新型材料以加速缝合线的愈合，而纳米纤维似乎是为此目的的合适材料。正如各种研究表明的那样，纳米纤维能够部分替代缺失的细胞外基质，并刺激缝合线中的细胞增殖和分化。因此，我们在兔模型中测试了纳米纤维膜和冷冻分级纳米纤维作为支持肠吻合愈合的潜在材料。
我们比较了冷冻分级壳聚糖和 PVA 纳米纤维与设计用于兔动物模型肠吻合愈合的壳聚糖和 PVA 纳米纤维膜。对吻合进行了生物力学和组织学测试。
与纳米纤维膜形成鲜明对比的是，分级纳米纤维确实对兔肠吻合的愈合有积极影响。分级纳米纤维能够到达深层，这对增加肠的机械强度至关重要。此外，分级纳米纤维导致富含胶原蛋白的 3D 组织的形成，明显超过了 2D 平纳米纤维膜的愈合效果。此外，分级壳聚糖纳米纤维消除了腹膜炎，显著刺激了吻合口的愈合，并导致微血管密度增加，以及更多的肌成纤维细胞和胶原蛋白 I 和 III。生物力学测试支持这些组织学发现。
我们得出结论，分级壳聚糖纳米纤维通过靶向刺激肠内产生胶原蛋白的细胞、平滑肌细胞和成纤维细胞，加速了兔结直肠吻合的愈合。我们认为，由于存在提供细胞黏附的生物相容性支架，胶原蛋白产生细胞直接受到刺激，并且通过缝合处免疫细胞的适当刺激间接受到刺激。
