School of Pharmaceutical Sciences, Zhejiang University, Zijingang Campus, No. 866 Yuhangtang Road, Hangzhou 310058, PR China.
Steroids. 2013 Sep;78(9):860-5. doi: 10.1016/j.steroids.2013.05.008. Epub 2013 May 16.
In the present study, it was demonstrated that the dichloromethane extract of Physalis pubescens L. (DEPP) had weak potential quinone reductase (QR) inducing activity, but an UPLC-ESI-MS method with glutathione (GSH) as the substrate revealed that the DEPP had electrophiles (with an α,β-unsaturated ketone moiety). These electrophiles could induce quinone reductase (QR) activity, which might be attributed to the modification of the highly reactive cysteine residues in Keap1. Herein, four withanolides, including three new compounds physapubescin B (2), physapubescin C (3), physapubescin D (4), together with one known steroidal compound physapubescin (1) were isolated. Structures of these compounds were determined by spectroscopic analysis and that of physapubescin C (3) was confirmed by a combination of molecular modeling and quantum chemical DFT-GIAO calculations. Evaluation of the QR inducing activities of all withanolides indicated potent activities of compounds 1 and 2, which had a common α,β-unsaturated ketone moiety.
在本研究中，表明酸浆属植物Physalis pubescens L. 的二氯甲烷提取物（DEPP）具有较弱的醌还原酶（QR）诱导活性，但使用谷胱甘肽（GSH）作为底物的 UPLC-ESI-MS 方法表明，DEPP 具有亲电试剂（具有α,β-不饱和酮部分）。这些亲电试剂可以诱导醌还原酶（QR）活性，这可能归因于 Keap1 中高反应性半胱氨酸残基的修饰。在此，分离得到了四种羽扇豆烷类化合物，包括三种新化合物 physapubescin B（2）、physapubescin C（3）、physapubescin D（4），以及一种已知的甾体化合物 physapubescin（1）。通过光谱分析确定了这些化合物的结构，并且 physapubescin C（3）的结构通过分子建模和量子化学 DFT-GIAO 计算的组合得到了证实。对所有羽扇豆烷类化合物的 QR 诱导活性的评估表明，具有共同的α,β-不饱和酮部分的化合物 1 和 2 具有很强的活性。
