Zhejiang Key Laboratory for Agro-Food Processing, Department of Food Science and Nutrition, Fuli Institute of Food Science, Zhejiang University, Hangzhou 310058, China.
Institute of Health Products, Chiatai Qingchunbao Pharmaceutical Co., Ltd., Hangzhou 310023, China.
Int J Biol Macromol. 2019 Jul 15;133:101-109. doi: 10.1016/j.ijbiomac.2019.04.019. Epub 2019 Apr 4.
Low molecular weight heparins (LMWHs) are currently used as an anticoagulant agent since unfractionated heparin (UFH) can cause serious adverse drug reactions. LMWHs are commercially prepared using different methods such as nitrous acid cleavage and β-elimination under strong reaction conditions or with harsh chemicals, which may cause the saccharide units within the polysaccharide backbone to be decomposed and noticeably modified. This study demonstrates an effective method for depolymerizing heparin via the production of large amounts of free radicals from HO/ascorbic acid and ultrasonic power; this results in highly pure products because ascorbic acid can decompose during the reaction, which is different from the previously reported HO/Cu method. The reaction conditions-including concentration of ascorbic acid, reaction temperature and intensity of ultrasonic power-were investigated and optimized. We found that the degradation behavior of heparin in this combined physicochemical process conformed to first-order reaction kinetics. The chemical composition and structures of different LMWHs were analyzed. The results showed the primary structure and sulfate esters were well preserved after the depolymerization, the major repeat units are (1-4)-linked glucosamine and iduronic acid. The further in vitro assays indicated that the LMWHs produced by HO/ascorbic acid with ultrasonic power have an anti-metastatic effect in A549 cells, which suggested the LMWHs rapidly prepared in this physicochemical way have a potential for anti-tumor metastatic function.
低分子量肝素（LMWHs）目前被用作抗凝剂，因为未分级肝素（UFH）会引起严重的药物不良反应。LMWHs 是通过不同的方法商业制备的，例如在强烈的反应条件下使用亚硝酸裂解和β消除，或者使用苛刻的化学物质，这可能导致多糖主链内的糖单位分解和明显修饰。本研究展示了一种通过 HO/抗坏血酸和超声功率产生大量自由基来解聚肝素的有效方法；这导致了高纯度的产物，因为抗坏血酸在反应过程中会分解，这与之前报道的 HO/Cu 方法不同。研究了并优化了包括抗坏血酸浓度、反应温度和超声功率强度在内的反应条件。我们发现，肝素在这种组合物理化学过程中的降解行为符合一级反应动力学。分析了不同 LMWHs 的化学成分和结构。结果表明，在解聚后，其一级结构和硫酸酯基得到了很好的保留，主要重复单元为（1-4）-连接的葡萄糖胺和艾杜糖醛酸。进一步的体外试验表明，HO/抗坏血酸与超声功率产生的 LMWHs 在 A549 细胞中具有抗转移作用，这表明通过这种物理化学方法快速制备的 LMWHs 具有抗肿瘤转移功能的潜力。
