Jiang Zhenlin, Wu Zhongshi, Deng Dengpu, Li Jiemin, Qi Xiaoke, Song Mingzhe, Liu Yuhong, Wu Qiying, Xie Xinlong, Chen Zeguo, Tang Zhenjie
Department of Cardiovascular Surgery, The Second Xiangya Hospital, Central South University, Changsha, China.
NHC Key Laboratory of Birth Defect for Research and Prevention, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, China.
Front Bioeng Biotechnol. 2022 May 19;10:844010. doi: 10.3389/fbioe.2022.844010. eCollection 2022.
Bioprosthetic heart valves (BHVs) used in clinics are fabricated via glutaraldehyde (GLUT) crosslinking, which results in cytotoxicity and causes eventual valve calcification after implantation into the human body; therefore, the average lifetime and application of BHVs are limited. To address these issues, the most commonly used method is modification with amino acids, such as glycine (GLY), which is proven to effectively reduce toxicity and calcification. In this study, we used the l-glutathione (GSH) in a new modification treatment based on GLUT-crosslinked bovine pericardium (BP) as the GLUT + GSH group, BPs crosslinked with GLUT as GLUT-BP (control group), and GLY modification based on GLUT-BP as the GLUT + GLY group. We evaluated the characteristics of BPs in different treatment groups in terms of biomechanical properties, cell compatibility, aldehyde group content detection, and the calcification content. Aldehyde group detection tests showed that the GSH can completely neutralize the residual aldehyde group of GLUT-BP. Compared with that of GLUT-BP, the endothelial cell proliferation rate of the GLUT + GSH group increased, while its hemolysis rate and the inflammatory response after implantation into the SD rat were reduced. The results show that GSH can effectively improve the cytocompatibility of the GLUT-BP tissue. In addition, the results of the uniaxial tensile test, thermal shrinkage temperature, histological and SEM evaluation, and enzyme digestion experiments proved that GSH did not affect the ECM stability and biomechanics of the GLUT-BP. The calcification level of GLUT-BP modified using GSH technology decreased by 80%, indicating that GSH can improve the anti-calcification performance of GLUT-BP. Compared with GLUT-GLY, GLUT + GSH yielded a higher cell proliferation rate and lower inflammatory response and calcification level. GSH can be used as a new type of anti-calcification agent in GLUT crosslinking biomaterials and is expected to expand the application domain for BHVs in the future.
临床使用的生物人工心脏瓣膜（BHVs）是通过戊二醛（GLUT）交联制备的，这会导致细胞毒性，并在植入人体后最终引起瓣膜钙化；因此，BHVs的平均使用寿命和应用受到限制。为了解决这些问题，最常用的方法是用氨基酸进行修饰，如甘氨酸（GLY），已证明其能有效降低毒性和钙化。在本研究中，我们在基于GLUT交联牛心包（BP）的新修饰处理中使用了L-谷胱甘肽（GSH）作为GLUT + GSH组，用GLUT交联的BP作为GLUT-BP（对照组），以及基于GLUT-BP的GLY修饰作为GLUT + GLY组。我们从生物力学性能、细胞相容性、醛基含量检测和钙化含量方面评估了不同处理组中BP的特性。醛基检测试验表明，GSH可以完全中和GLUT-BP的残留醛基。与GLUT-BP相比，GLUT + GSH组的内皮细胞增殖率增加，而其溶血率和植入SD大鼠后的炎症反应降低。结果表明，GSH可以有效提高GLUT-BP组织的细胞相容性。此外，单轴拉伸试验、热收缩温度、组织学和扫描电镜评估以及酶消化实验的结果证明，GSH不会影响GLUT-BP的细胞外基质稳定性和生物力学性能。使用GSH技术修饰的GLUT-BP的钙化水平降低了80%，表明GSH可以提高GLUT-BP的抗钙化性能。与GLUT-GLY相比，GLUT + GSH产生了更高的细胞增殖率、更低的炎症反应和钙化水平。GSH可以用作GLUT交联生物材料中的新型抗钙化剂，有望在未来扩大BHVs的应用领域。
