College of Pharmacy, Yeungnam University, Gyeongsan, Gyeongbuk 712-749, Korea.
Phytother Res. 2010 Nov;24(11):1716-9. doi: 10.1002/ptr.3203.
During the screening effort to discover new types of protein tyrosine phosphatase 1B (PTP1B) inhibitors, it was found that a MeOH extract of the leaves and stems of Weigela subsessilis (Caprifoliaceae) inhibited the enzyme activity. By means of an in vitro bioassay-guided fractionation on the MeOH extract, two 24-norursane triterpenes, ilekudinol A (1) and ilekudinol B (2), were isolated as active metabolites. Compounds 1 and 2 inhibited PTP1B with IC(50) values of 29.1 ± 2.8 and 5.3 ± 0.5 μM, respectively. Kinetic studies suggest that both 1 and 2 are non-competitive inhibitors of PTP1B. The findings indicate that the free carboxyl group at C-28 in this type of triterpenes plays a critical role in the inhibition of PTP1B.
在筛选新型蛋白酪氨酸磷酸酶 1B（PTP1B）抑制剂的过程中，发现薇甘菊（忍冬科）叶和茎的甲醇提取物抑制了该酶的活性。通过对甲醇提取物进行体外生物测定指导的分离，分离出两种 24-降齐墩果烷型三萜，ilekudinol A（1）和 ilekudinol B（2），作为活性代谢物。化合物 1 和 2 对 PTP1B 的抑制作用的 IC50 值分别为 29.1 ± 2.8 和 5.3 ± 0.5 μM。动力学研究表明，1 和 2 均为 PTP1B 的非竞争性抑制剂。研究结果表明，此类三萜中 C-28 位的游离羧基在抑制 PTP1B 中起着关键作用。
