摘要
为从化学角度探索单宁酸与牛颈静脉的交联机制,使用5种含有单宁酸不同特征基团的模式分子,分别对戊二醛固定后的牛颈静脉带瓣血管进行交联处理。体内实验采用20只SD大鼠皮下植入处理后的带瓣血管,21和60 d后用原子吸收光谱法测定抗钙化效果,用Masson和EVG染色测定交联程度。体外采用热稳定性和酶解实验检测交联程度,并使用傅里叶变换红外光谱检测带瓣血管化学结构的变化,推测单宁酸与带瓣血管交联作用的类型;进一步在确定交联类型的体系中加入系列浓度梯度(0.1、0.3、0.5、1 M)的尿素,对交联类型使用同样方法进行验证。结果显示,含多酚羟基的单宁酸组带瓣血管交联程度最高,21和60 d钙含量分别为2.25、8.26 mg/g,抗钙化能力最优(P<0.05);傅里叶变换红外光谱图中,单宁酸组带瓣血管有氢键生成。浓度梯度尿素实验表明,随着尿素浓度的增加,单宁酸与牛颈静脉组织交联程度下降(P<0.05),60 d时单宁酸组钙含量为8.10 mg/g,远低于加入0.1 M尿素组的16.83 mg/g和0.5 M尿素组的50.76 mg/g(P<0.001)。研究表明,单宁酸对牛颈静脉带瓣血管的交联作用是由其所含的多酚羟基与组织中蛋白质基团间通过氢键而产生的,为进一步优化单宁酸抗钙化处理流程提供依据。
The aim of this study was to investigate chemical reactions of tannic acid(TA) with bovine jugular vein(BJV). Glutaraldehyde-fixed BJVs were subsequently treated with TA or four substitutional compounds, which contained four characteristic chemical groups of tannic acid. The treated BJVs were implanted subcutaneously into 20 SD rats for 21 and 60 days. The calcium content of the explanted tissues was assessed using atomic absorption spectrometry, and the degree of cross-linking was measured by Masson and EVG staining. In vitro, they were characterized with thermal stability, resistance to enzymatic hydrolysis, mechanical properties. The Fourier transform infrared spectroscopy(FTIS) was employed to inspect the changes of absorption curve. Furthermore, a gradient concentration of urea(0.1, 0.3, 0.5 and 1 M) was used to verify if hydrogen bond was formed. Tannic acid treated BJV, with polyphenolic hydroxyl groups in the compound, showed the best performance among the all BJVs. Which suggested effective cross-linking was formed in the tissue, and the calcium content at 21 d and 60 d was 2.25 mg/g and 8.26 mg/g respectively(P< 0.05). FTIS results indicated that hydrogen bond was formed in TA group and it was confirmed by urea test. The urea test showed that the effect of cross-linking between tissue decreased(P< 0.05) with the increase of urea concentration, and the calcium content of TA group was 8.10 mg/g at 60 d, which was much lower than 16.83 mg/g of the 0.1 M urea group and 50.76 mg/g of the 0.5 M urea group(P < 0.001). Our results demonstrated that the hydrogen bond was formed between polyphenolic hydroxyl groups and proteins in TA treated BJVs. It may provide a clue to improve the stability of the reaction system.
作者
郑晓冰
周建业
王德
戴泽辉
郭宝华
Zheng Xiaobing;Zhou Jianye;Wang De;Dai Zehui;Guo Baohua(State Key Laboratory of Cardiovascular Disease,Fu Wai Hospital,National Center for Cardiovascular Diseases,Chinese Academy of Medical Sciences and Peking Union Medical College,Beijing 100037,China;Key Laboratory of Advanced Materials,Ministry of Education,Department of Chemical Engineering,Tsinghua University,Beijing 100037,China)
出处
《中国生物医学工程学报》
CAS
CSCD
北大核心
2019年第6期733-741,共9页
Chinese Journal of Biomedical Engineering
基金
国家重点研发计划课题(2016YFC1101002)
关键词
牛颈静脉
单宁酸
交联
氢键
钙化
bovine jugular vein
tannic acid
cross-linking
hydrogen bonding
calcification
