Bioactive Botanical Research Laboratory, Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, RI 02881, USA.
Food Chem Toxicol. 2012 May;50(5):1369-76. doi: 10.1016/j.fct.2012.02.031. Epub 2012 Feb 23.
Maplexins A-I are a series of structurally related gallotannins recently isolated from the red maple (Acer rubrum) species. They differ in number and location of galloyl derivatives attached to 1,5-anhydro-glucitol. Here, maplexins A-I were evaluated for anticancer effects against human tumorigenic (colon, HCT-116; breast, MCF-7) and non-tumorigenic (colon, CCD-18Co) cell lines. The maplexins which contained two (maplexins C-D) or three (maplexins E-I) galloyl derivatives each, inhibited cancer cell growth while those with only one galloyl group (maplexins A-B) did not. Moreover, maplexins C-D showed greater antiproliferative effects than maplexins E-I (IC(50)=59.8-67.9 and 95.5-108.5 μM vs. 73.7-165.2 and 115.5-182.5 μM against HCT-116 and MCF-7 cells, respectively). Notably, the cancer cells were up to 2.5-fold more sensitive to the maplexins than the normal cells. In further mechanistic studies, maplexins C-D (at 75 μM concentrations) induced apoptosis and arrested cell cycle (in the S-phase) of the cancer cells. These results suggest that the number of galloyl groups attached to the 1,5-anhydro-glucitol moiety in these gallotannins are important for antiproliferative activity. Also, this is the first in vitro anticancer study of maplexins.
Maplexins A-I 是一类结构相关的鞣花单宁，最近从红枫（Acer rubrum）物种中分离得到。它们在与 1,5-脱水葡萄糖结合的没食子酰基衍生物的数量和位置上有所不同。在这里，对 maplexins A-I 进行了抗癌活性评价，针对人肿瘤发生（结肠，HCT-116；乳腺，MCF-7）和非肿瘤发生（结肠，CCD-18Co）细胞系。含有两个（maplexins C-D）或三个（maplexins E-I）没食子酰基衍生物的 maplexins 抑制癌细胞生长，而仅含有一个没食子酰基的 maplexins（maplexins A-B）则没有。此外，maplexins C-D 比 maplexins E-I 显示出更强的抗增殖作用（IC50=59.8-67.9 和 95.5-108.5 μM 与 HCT-116 和 MCF-7 细胞分别为 73.7-165.2 和 115.5-182.5 μM）。值得注意的是，癌细胞对 maplexins 的敏感性比正常细胞高 2.5 倍。在进一步的机制研究中，maplexins C-D（在 75 μM 浓度下）诱导癌细胞凋亡并使细胞周期（在 S 期）停滞。这些结果表明，这些鞣花单宁中与 1,5-脱水葡萄糖结合的没食子酰基基团的数量对其抗增殖活性很重要。此外，这是 maplexins 的首次体外抗癌研究。
