Leibniz Institute of Plant Biochemistry, Weinberg 3, D-06120 Halle (Saale), Germany.
J Ethnopharmacol. 2011 Apr 12;134(3):781-8. doi: 10.1016/j.jep.2011.01.038. Epub 2011 Feb 1.
For identification of the active constituents we investigated the anticancer activity of cardenolides from Streptocaulon tomentosum Wight & Arn. (Asclepiadaceae) and from Nerium oleander L. (Apocynaceae) which are both used against cancer in the traditional medicine in their region of origin.
MATERIAL, METHODS AND RESULTS: The antiproliferative activity of cardenolides isolated from roots of Streptocaulon tomentosum (IC(50)<1-15.3 μM after 2 days in MCF7) and of cardenolide containing fractions from the cold aqueous extract of Nerium oleander leaves ("Breastin", mean IC(50) 0.85 μg/ml in a panel of 36 human tumor cell lines), their influence on the cellular viability and on the cell cycle (block at the G2/M-phase or at the S-phase in tumor cells, respectively) were determined using different cell lines. The murine cell line L929 and normal non-tumor cells were not affected. Bioactivity guided fractionation of Breastin resulted in the isolation of the monoglycosidic cardenolides oleandrine, oleandrigeninsarmentoside, neritaloside, odoroside H, and odoroside A (IC(50)-values between 0.010 and 0.071 μg/ml).
The observed anticancer activities of extracts and isolated cardenolides are in agreement with the ethnomedicinal use of Streptocaulon tomentosum and Nerium oleander. The most active anticancer compounds from both species are monoglycosidic cardenolides possessing the 3β,14β-dihydroxy-5β-card-20(22)-enolide structure with or without an acetoxy group at C-16. The results indicate that the cytotoxic effects are induced by the inhibition of the plasma membrane bound Na(+)/K(+)-ATPase.
为了鉴定活性成分，我们研究了毛喉鞘蕊花（夹竹桃科）和夹竹桃（夹竹桃科）中的强心苷的抗癌活性，这些植物在其起源地的传统医学中都被用于治疗癌症。
材料、方法和结果：从毛喉鞘蕊花（IC（50）<1-15.3 μM，在 MCF7 中培养 2 天后）和夹竹桃冷水性提取物中分离出的强心苷（“Breastin”，在 36 个人类肿瘤细胞系的面板中平均 IC（50）为 0.85 μg/ml）及其含苷类的部分的细胞增殖活性和细胞周期（在肿瘤细胞中分别在 G2/M 期或 S 期阻滞）用不同的细胞系进行了测定。鼠源细胞系 L929 和正常非肿瘤细胞不受影响。Breastin 的生物活性导向分离得到了单糖苷类强心苷毛喉苷、毛喉苷异戊烯基糖苷、奈替利苷、奥多苷 H 和奥多苷 A（IC（50）值在 0.010 到 0.071 μg/ml 之间）。
提取物和分离出的强心苷的观察到的抗癌活性与毛喉鞘蕊花和夹竹桃的民族医学用途一致。两种植物中最具活性的抗癌化合物是具有 3β,14β-二羟基-5β-卡-20(22)-烯醇内酯结构的单糖苷类强心苷，在 C-16 位上有或没有乙酰氧基。结果表明，细胞毒性作用是通过抑制质膜结合的 Na(+)/K(+)-ATP 酶引起的。
