睡茄内酯代表了一类重要的具有甾体内酯核心的天然产物。其中许多含有 α,β-不饱和羰基部分，对巯基（包括蛋白质半胱氨酸硫醇）具有高反应性。具有显着抗肿瘤和抗炎作用的不同茄内酯已被证明可与致癌激酶（BTK、IKKβ、Zap70）、代谢酶（Prdx-1/6、Pin1、PHGDH）活性位点中暴露的半胱氨酸形成稳定的共价复合物、转录因子（Nrf2、NFκB、C/EBPβ）和其他结构和信号分子（GFAP、β-微管蛋白、p97、Hsp90、波形蛋白、Mpro、IPO5、NEMO...）。本综述分析了六种主要醉茄内酯（醉茄素 A、酸浆素 A、醉茄素 A、4β-羟基醉茄内酯 E、醉茄酮和 Tubocapsanolide A）与约 20 种蛋白质的关键半胱氨酸残基之间通过迈克尔加成烷基化反应形成的共价复合物以及由此产生的生物效应。醉茄内酯的 α,β-不饱和羰基系统与反应性蛋白硫醇的共价缀合可以与大量可溶性蛋白和膜蛋白发生。它指出了一种一般机制，已用主要天然产物醉茄素 A 进行了很好的描述，但对于大多数含有反应性（亲电子）烯酮部分的醉茄内酯可能有效，该部分易于与蛋白质的半胱氨酰残基发生共价反应。在研究新的茄内酯的作用机制时，应考虑反应蛋白的多样性。应进行蛋白质组学和网络分析来捕获和比较主要茄内酯的半胱氨酸共价结合图，以便在其活性和/或不良作用的起源处识别蛋白质靶点。半胱氨酸的筛选将有助于了解作用机制并设计半胱氨酸反应性亲电候选药物。版权所有 © 2024 作者。由爱思唯尔公司出版。保留所有权利。

Withanolides represent an important category of natural products with a steroidal lactone core. Many of them contain an α,β-unsaturated carbonyl moiety with a high reactivity toward sulfhydryl groups, including protein cysteine thiols. Different withanolides endowed with marked antitumor and anti-inflammatory have been shown to form stable covalent complexes with exposed cysteines present in the active site of oncogenic kinases (BTK, IKKβ, Zap70), metabolism enzymes (Prdx-1/6, Pin1, PHGDH), transcription factors (Nrf2, NFκB, C/EBPβ) and other structural and signaling molecules (GFAP, β-tubulin, p97, Hsp90, vimentin, Mpro, IPO5, NEMO, …). The present review analyzed the covalent complexes formed through Michael addition alkylation reactions between six major withanolides (withaferin A, physalin A, withangulatin A, 4β-hydroxywithanolide E, withanone and tubocapsanolide A) and key cysteine residues of about 20 proteins and the resulting biological effects. The covalent conjugation of the α,β-unsaturated carbonyl system of withanolides with reactive protein thiols can occur with a large set of soluble and membrane proteins. It points to a general mechanism, well described with the leading natural product withaferin A, but likely valid for most withanolides harboring a reactive (electrophilic) enone moiety susceptible to react covalently with cysteinyl residues of proteins. The multiplicity of reactive proteins should be taken into account when studying the mechanism of action of new withanolides. Proteomic and network analyses shall be implemented to capture and compare the cysteine covalent-binding map for the major withanolides, so as to identify the protein targets at the origin of their activity and/or unwanted effects. Screening of the cysteinome will help understanding the mechanism of action and designing cysteine-reactive electrophilic drug candidates.Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.