Notoginsenoside R1 alleviates oxidized low-density lipoprotein-induced apoptosis, inflammatory response, and oxidative stress in HUVECS through modulation of XIST/miR-221-3p/TRAF6 axis

Abstract

Background:Atherosclerosis is a common reason for acute cardio-cerebral vascular diseases. The purpose of this study was to clarify the functional effects of Notoginsenoside R1 (NGR1) on atherosclerosis. MethodsHUVECS were exposed to oxidized low-density lipoprotein (ox-LDL) in the current study. The proliferation ability of HUVECS was measured by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-2H-tetrazol-3-ium bromide (MTT). Flow cytometry assays were performed to evaluate the apoptosis of HUVECS. Ox-LDL caused inflammatory response and oxidative stress were assessed by checking pro-inflammatory cytokines and intracellular reactive oxygen species (ROS), malondialdehyde (MDA), and superoxide dismutase (SOD). The regulatory roles of NGR1 in HUVECs were measured by real-time quantitative polymerase chain reaction (RT-qPCR) and western blot assays. The interaction relationship between miR-221-3p and X-inactive specific transcript (XIST) or TNF-receptor-associated factor 6 (TRAF6) was predicted by bioinformatics tools. Dual-luciferase reporter and RNA pull-down assays were used to confirm the interaction relationship. ResultsCurrently, ox-LDL inhibited proliferation and induced apoptosis, inflammatory response, and oxidative stress in HUVECs, which were alleviated by treatment with NGR1. Importantly, the increase of XIST in ox-LDL-induced HUVECs was abolished by NGR1. In addition, the gain-of-functional experiment suggested that the upregulation of XIST neutralized the protection effects of NGR1 in HUVECs treated with ox-LDL. In addition, miR-221-3p was a target of XIST in HUVECs as confirmed by dual-luciferase reporter and RNA pull-down assays. Furthermore, miR-221-3p interacted with TRAF6, and NGR1 regulated proliferation, apoptosis, inflammatory response, and oxidative stress in HUVECs exposed to ox-LDL by regulation of the XIST/miR-221-3p/TRAF6 axis through Nuclear Factor Kappa B (NF-κB) pathway. ConclusionNGR1 could exert regulatory functions in ox-LDL-induced HUVECS by regulation of XIST/miR-221-3p/TRAF6 axis, which provided valuable insights into the development of potential therapeutic strategy for atherosclerosis.