Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Gachibowli, Telangana, India.
PLoS One. 2018 Nov 7;13(11):e0200053. doi: 10.1371/journal.pone.0200053. eCollection 2018.
Withania somnifera (Ashwagandha) is an efficient medicinal plant known in Ayurveda and Chinese medicine since ancient times, whose extracts are consumed orally as food supplement or as a health tonic owing to its several restorative properties for various CNS disorders, inflammation, tumour, stress, rheumatism etc. In this study, we have analyzed the binding interaction of four derivatives of Withania somnifera (Withanolide A, Withanolide B, Withanoside IV and Withanoside V) with HSA because of their important pharmacological properties. To unravel the binding between derivatives of Withania somnifera and HSA, fluorescence spectroscopy was used. Binding studies were further studied by molecular docking and dynamics and results confirmed greater stability upon binding of derivatives with HSA. Circular dichroism data illustrated change in the secondary structure of protein upon interaction with these derivatives, particularly the helical structure was increased and β-sheets and random coils were decreased. Furthermore, morphological and topological changes were observed using AFM and TEM upon binding of ligands with HSA indicating that HSA-withnoside/withanolide complexes were formed. All the results cumulatively demonstrate strong binding of withanosides and withanolides derivatives with serum albumin, which should further be explored to study the pharmacokinetics and pharmacodynamics of these derivatives.
睡茄（印度人参）是一种有效的药用植物，在古印度阿育吠陀和中医药中就已为人所知，其提取物因其对各种中枢神经系统疾病、炎症、肿瘤、应激、风湿等的多种恢复特性，被作为食品补充剂或健康补品口服。在这项研究中，我们分析了睡茄的四种衍生物（睡茄苷 A、睡茄苷 B、醉茄苷 IV 和醉茄苷 V）与 HSA 的结合相互作用，因为它们具有重要的药理学特性。为了揭示睡茄衍生物与 HSA 之间的结合，我们使用荧光光谱法。通过分子对接和动力学进一步研究了结合研究，结果证实衍生物与 HSA 的结合更稳定。圆二色性数据表明，在与这些衍生物相互作用时，蛋白质的二级结构发生变化，特别是螺旋结构增加，β-折叠和无规卷曲减少。此外，在配体与 HSA 结合时，使用 AFM 和 TEM 观察到形态和拓扑变化，表明形成了 HSA-醉茄/睡茄复合物。所有结果都证明了与血清白蛋白的强烈结合，这应该进一步研究以研究这些衍生物的药代动力学和药效学。
