College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201602, People \'s Republic of China.
Ruichang Hospital of Traditional Chinese Medicine, Jiujiang 332200, People \'s Republic of China.
Curr Pharm Biotechnol. 2022;23(7):998-1008. doi: 10.2174/1389201022666210602105609.
Topoisomerase I (Topo I) is a key target of many antitumor drugs in vivo. Alkaloids in Sophora alopecuroides L. can reportedly inhibit Topo I activity, but the pharmacodynamic material basis has not yet been determined.
This study aimed to rapidly identify active components which inhibit Topo I in S. alopecuroides L.
Affinity ultrafiltration coupled with ultra-performance liquid chromatography-quadrupole time of flight-mass spectrometry (UF-UPLC-QTOF-MS) screening system based on Topo I protein was established to screen and isolate a total alkaloid fraction in S. alopecuroides L. Topo I inhibitory activity and anti-tumor proliferation activity of the screened components were evaluated, and their molecular mechanisms were studied.
Six compounds that bound specifically to Topo I were obtained. Further screening showed that matrine, cytisine, and sophoridine presented higher inhibitory activity on Topo I and were able to inhibit the proliferation of breast cancer MDA-MB-468 cells with IC50 values of 9.40 ± 1.12 mM, 17.4 ± 2.20 mM, and 10.4 ± 1.37 mM, respectively. To the best of our knowledge, their dual molecular mechanisms against Topo I have not discussed to date. In this study, the following dual mechanisms are reviewed for the first time: (1) stabilization of the Topo I-DNA complex and (2) inhibition or blocking of Topo I binding to DNA.
Matrine, cytisine, and sophoridine from S. alopecuroides L. were defined as the active components possessing Topo I inhibitory activity, and their pharmacological mechanism was confirmed, which provided an important base for further research and development of antitumor components from S. alopecuroides L.
拓扑异构酶 I（Topo I）是许多体内抗肿瘤药物的关键靶标。苦参中的生物碱据称可以抑制 Topo I 活性，但药效物质基础尚未确定。
本研究旨在快速鉴定苦参中抑制 Topo I 的活性成分。
建立基于 Topo I 蛋白的亲和超滤-超高效液相色谱-四极杆飞行时间质谱（UF-UPLC-QTOF-MS）筛选系统，筛选和分离苦参总生物碱部位。评价筛选成分的 Topo I 抑制活性和抗肿瘤增殖活性，并研究其分子机制。
获得了 6 种与 Topo I 特异性结合的化合物。进一步筛选表明，苦参碱、野靛碱和槐定碱对 Topo I 具有更高的抑制活性，能够抑制乳腺癌 MDA-MB-468 细胞的增殖，IC50 值分别为 9.40±1.12 mM、17.4±2.20 mM 和 10.4±1.37 mM。据我们所知，它们针对 Topo I 的双重分子机制迄今尚未讨论。在本研究中，首次综述了以下双重机制：（1）Topo I-DNA 复合物的稳定化，和（2）Topo I 与 DNA 结合的抑制或阻断。
苦参中的苦参碱、野靛碱和槐定碱被定义为具有 Topo I 抑制活性的活性成分，其药理机制得到了证实，为进一步研究和开发苦参抗肿瘤成分提供了重要基础。
