Effect of Withanolide A on 7-Ketocholesterol Induced Cytotoxicity in hCMEC/D3 Brain Endothelial Cells

Abstract

Withanolide A is a naturally occurring phytochemical that is found in Ashwagandha (Withania somnifera, 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.

Targeting 7KCh-Induced Cell Death Response Mediated by p38, P2X7 and GSDME in Retinal Pigment Epithelium Cells with Sterculic Acid

“…First of all, we evaluated the role of apoptosis in the cytotoxic response of 7KCh. Apoptosis and oxyapoptophagy are the main cell death mechanisms described for 7KCh, and, in general, for oxysterols [25,29,[46][47][48][49][50][51][52][53][54][55][56]. Oxyapoptophagy is a type of cell death characteristic of oxysterols that combines the activation of apoptosis and autophagy [25,29,[49][50][51][52]54,56].…”

“…Apoptosis and oxyapoptophagy are the main cell death mechanisms described for 7KCh, and, in general, for oxysterols [25,29,[46][47][48][49][50][51][52][53][54][55][56]. Oxyapoptophagy is a type of cell death characteristic of oxysterols that combines the activation of apoptosis and autophagy [25,29,[49][50][51][52]54,56]. In our previous work, we showed alterations in the expression of several genes associated with apoptosis with 7KCh-treatment in mRPE cells, such as APAF1, GADD45A, PMAIP1 and TP53I3 [34], suggesting that apoptosis is induced in response to 7KCh in these cells.…”

Expression of anti and pro‐inflammatory genes in human endothelial cells activated by 25‐hydroxycholesterol: A comparison of rivaroxaban and dabigatran

“…Moreover, dabigatran was able to completely repair the DNA SSBs induced by 25‐OHC. Soh et al 24 showed that endothelial cells that had been treated with 7‐ketocholesterol showed a 4.6‐fold increase in eNOS mRNA expression, and a larger 10.4‐fold increase in inducible NO synthase (iNOS) mRNA expression. Dabigatran was found to significantly enhance catalase and superoxide dismutase activity and suppress iNOS in a rabbit model of acute myocardial infarction, 14 also rivaroxaban reduced iNOS, MCP‐1 and VCAM‐1 expression in vascular endothelium inducted by LPS 13 …”

Chantriolides F–P, Highly Oxidized Withanolides with Hepatoprotective Activity from Tacca chantrieri

“…In addition, withanolides were reported from the Taccaceae, Myrtaceae, Labiataem, Dioscoreaceae, and Asteraceae families, and from the soft corals (marine source) as well. Due to their unique structures [ 1 , 2 , 3 , 4 , 5 ] and diverse biological activities [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 ], withanolides have captured extensive attention, and over the past decade, more than 500 new withanolides of natural origin have been discovered [ 14 , 15 , 16 ].…”