目的:心肌梗死(MI)是导致不可逆的功能性心脏组织损失的主要原因,需要新的再生策略。这项研究评估了再细胞化心脏贴片的潜在治疗效果,将胎儿心肌支架与大鼠胎儿心肌细胞和脱细胞人羊膜相结合,在成年Wistar大鼠模型中。
方法:从已经流产的14至16周龄的人胎儿获得脱细胞心肌组织。使用化学洗涤剂(0.1%EDTA和0.2%十二烷基硫酸钠)制备胎儿细胞外基质(ECM),通过扫描电子显微镜(SEM)和MTT法表征了生物支架的微观结构和生物相容性,分别。从一天大的Wistar大鼠的心室中提取新生心肌细胞,并通过针对Connexin-43和α-平滑肌肌动蛋白的免疫染色进行表征。将分离的细胞接种到去细胞化的组织上并用去细胞化的羊膜覆盖。16只健康成年Wistar大鼠被系统地分配到对照组和MI组。MI是通过动脉结扎诱导的。手术后14天,MI组接受了工程化贴剂.植入后两周,动物被安乐死,并收获心脏进行移植物评估。
结果:组织学分析,DAPI染色,超结构检查证实了细胞元素的成功消耗,同时保持胎儿ECM和结构的完整性。随后的组织学和免疫组织化学(IHC)评估证实了心肌细胞在支架上的有效接种。这些工程补丁在MI模型中的应用导致血管生成增加,减少纤维化,并限制了瘢痕组织的形成,植入的心肌细胞在移植部位保持存活,表明预期的体内细胞活力。
结论:这项研究表明,多层再细胞化心脏补片是心肌梗死的一种有前途的手术干预措施,通过促进血管生成展示了巨大的潜力,减轻纤维化,减少MI模型中的瘢痕组织形成。这些特征对于增强MI患者的治疗效果至关重要,关注梗死后心肌结构和功能的恢复。
OBJECTIVE: Myocardial infarction (MI) is a leading cause of irreversible functional cardiac tissue loss, requiring novel regenerative strategies. This study assessed the potential therapeutic efficacy of recellularized cardiac patches, incorporating fetal myocardial scaffolds with rat fetal cardiomyocytes and acellular human amniotic membrane, in adult Wistar rat models of MI.
METHODS: Decellularized myocardial tissue was obtained from 14 to 16 week-old human fetuses that had been aborted. Chemical detergents (0.1% EDTA and 0.2% sodium dodecyl sulfate) were used to prepare the fetal extracellular matrix (ECM), which was characterized for bio-scaffold microstructure and biocompatibility via scanning electron microscopy (SEM) and MTT assay, respectively. Neonatal cardiomyocytes were extracted from the ventricles of one-day-old Wistar rats\' littermates and characterized through immunostaining against Connexin-43 and α-smooth muscle actin. The isolated cells were seeded onto decellularized tissues and covered with decellularized amniotic membrane. Sixteen healthy adult Wistar rats were systematically allocated to control and MI groups. MI was induced via arterial ligation. Fourteen days post-operation, the MI group was received the engineered patches. Following a two-week post-implantation period, the animals were euthanized, and the hearts were harvested for the graft evaluation.
RESULTS: Histological analysis, DAPI staining, and ultra-structural examination corroborated the successful depletion of cellular elements, while maintaining the integrity of the fetal ECM and architecture. Subsequent histological and immunohistochemichal (IHC) evaluations confirmed effective
cardiomyocyte seeding on the scaffolds. The application of these engineered patches in MI models resulted in increased angiogenesis, reduced fibrosis, and restricted scar tissue formation, with the implanted cardiomyocytes remaining viable at graft sites, indicating prospective in vivo cell viability.
CONCLUSIONS: This study suggests that multi-layered recellularized cardiac patches are a promising surgical intervention for myocardial infarction, showcasing significant potential by promoting angiogenesis, mitigating fibrosis, and minimizing scar tissue formation in MI models. These features are pivotal for enhancing the therapeutic outcomes in MI patients, focusing on the restoration of the myocardial structure and function post-infarction.