Zheng Meng, Guo Jiazhi, Li Qing, Yang Jian, Han Yi, Yang Hongcai, Yu Mali, Zhong Lianmei, Lu Di, Li Limei, Sun Lin
Yunnan Key Laboratory of Stem Cell and Regenerative Medicine, Science and Technology Achievement Incubation Center, Kunming Medical University, Kunming, 650500, China.
Department of Biomedical Engineering, Materials Research Institute, The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, 16802, USA.
Bioact Mater. 2020 Sep 6;6(2):404-419. doi: 10.1016/j.bioactmat.2020.08.008. eCollection 2021 Feb.
Vascular grafts must avoid negative inflammatory responses and thrombogenesis to prohibit fibrotic deposition immediately upon implantation and promote the regeneration of small diameter blood vessels (<6 mm inner diameter). Here, polyurethane (PU) elastomers incorporating anti-coagulative and anti-inflammatory Gastrodin were fabricated. The films had inter-connected pores with porosities equal to or greater than 86% and pore sizes ranging from 250 to 400 μm. Incorporation of Gastrodin into PU films resulted in desirable mechanical properties, hydrophilicity, swelling ratios and degradation rates without collapse. The released Gastrodin maintained bioactivity over 21 days as assessed by its anti-oxidative capability. The Gastrodin/PU had better anti-coagulation response (less observable BSA, fibrinogen and platelet adhesion/activation and suppressed clotting in whole blood). Red blood cell compatibility, measured by hemolysis, was greatly improved with 2Gastrodin/PU compared to other Gastrodin/PU groups. Notably, Gastrodin/PU upregulated anti-oxidant factors Nrf2 and HO-1 expression in HO treated HUVECs, correlated with decreasing pro-inflammatory cytokines TNF-α and IL-1β in RAW 264.7 cells. Upon implantation in a subcutaneous pocket, PU was encapsulated by an obvious fibrous capsule, concurrent with a large amount of inflammatory cell infiltration, while Gastrodin/PU induced a thinner fibrous capsule, especially 2Gastrodin/PU. Further, enhanced adhesion and proliferation of HUVECs seeded onto films demonstrated that 2Gastrodin/PU could help cell recruitment, as evidenced by rapid host cell infiltration and substantial blood vessel formation . These results indicate that 2Gastrodin/PU has the potential to facilitate blood vessel regeneration, thus providing new insight into the development of clinically effective vascular grafts.
血管移植物必须避免负面的炎症反应和血栓形成,以防止植入后立即发生纤维化沉积,并促进小直径血管(内径<6毫米)的再生。在此,制备了含有抗凝和抗炎天麻素的聚氨酯(PU)弹性体。这些薄膜具有相互连接的孔隙,孔隙率等于或大于86%,孔径范围为250至400μm。将天麻素掺入PU薄膜中可获得理想的机械性能、亲水性、溶胀率和降解率,且不会塌陷。通过其抗氧化能力评估,释放的天麻素在21天内保持生物活性。天麻素/PU具有更好的抗凝反应(观察到的牛血清白蛋白、纤维蛋白原和血小板粘附/活化较少,全血凝血受到抑制)。与其他天麻素/PU组相比,通过溶血测量的红细胞相容性在2%天麻素/PU组中有显著改善。值得注意的是,天麻素/PU上调了经HO处理的人脐静脉内皮细胞中抗氧化因子Nrf2和HO-1的表达,这与RAW 264.7细胞中促炎细胞因子TNF-α和IL-1β的减少相关。植入皮下袋后,PU被明显的纤维囊包裹,同时伴有大量炎症细胞浸润,而天麻素/PU诱导形成较薄的纤维囊,尤其是2%天麻素/PU。此外,接种在薄膜上的人脐静脉内皮细胞的粘附和增殖增强,表明2%天麻素/PU有助于细胞募集,快速的宿主细胞浸润和大量血管形成证明了这一点。这些结果表明,2%天麻素/PU有促进血管再生的潜力,从而为临床有效的血管移植物的开发提供了新的见解。