Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119260, Singapore.
Neurobiology Research Programme, Life Sciences Institute, National University of Singapore, Singapore 119260, Singapore.
Cells. 2022 Jan 28;11(3):457. doi: 10.3390/cells11030457.
Withanolide A is a naturally occurring phytochemical that is found in Ashwagandha (, fam. Solanaceae) or Indian Ginseng. In the current study, we elucidated the effect of withanolide A on 7-ketocholesterol (7KC) induced injury in hCMEC/D3 human brain endothelial cells. 7KC is a cholesterol oxidation product or oxysterol that is present in atherosclerotic plaques and is elevated in the plasma of patients with hypercholesterolemia and/or diabetes mellitus. Results showed that withanolide A significantly reduced the effects of 7KC, which include loss of endothelial cell viability, increase in expression of pro-inflammatory genes-IL-1β, IL-6, IL-8, TNF-α, cyclooxygenase-2 (COX-2), increased COX-2 enzyme activity, increased ROS formation, increased expression of inducible nitric oxide synthase and genes associated with blood clotting, including Factor 2/thrombin, Factor 8, von Willebrand factor, and thromboxane A synthase, and increased human thrombin enzyme activity. Some of the above effects of withanolide A on 7KC were reduced in the presence of the glucocorticoid receptor antagonist, mifepristone (RU486). These findings suggest that the glucocorticoid receptor could play a role in the cytoprotective, antioxidant, and anti-clotting effects of withanolide A against 7KC. Further studies are necessary to elucidate the detailed mechanisms of action of withanolide A against oxysterol-induced injury.
Withanolide A 是一种天然存在的植物化学物质,存在于 Ashwagandha(茄科)或印度人参中。在目前的研究中,我们阐明了 withanolide A 对 7-酮胆固醇(7KC)诱导的 hCMEC/D3 人脑血管内皮细胞损伤的影响。7KC 是一种胆固醇氧化产物或氧化固醇,存在于动脉粥样硬化斑块中,并且在高胆固醇血症和/或糖尿病患者的血浆中升高。结果表明,withanolide A 可显著降低 7KC 的作用,包括内皮细胞活力丧失、促炎基因-IL-1β、IL-6、IL-8、TNF-α、环氧化酶-2(COX-2)的表达增加、COX-2 酶活性增加、ROS 形成增加、诱导型一氧化氮合酶表达增加以及与血液凝结相关的基因,包括因子 2/凝血酶、因子 8、血管性血友病因子和血栓烷 A 合酶,以及人凝血酶酶活性增加。在存在糖皮质激素受体拮抗剂米非司酮(RU486)的情况下,withanolide A 对 7KC 的上述一些作用会降低。这些发现表明,糖皮质激素受体可能在 withanolide A 对 7KC 的细胞保护、抗氧化和抗凝血作用中发挥作用。需要进一步研究阐明 withanolide A 对抗氧化固醇诱导损伤的详细作用机制。