Protective Effects of Oxymatrine on Vascular Endothelial Cells from High-Glucose-Induced Cytotoxicity by Inhibiting the Expression of A2B Receptor

Abstract

Background/Aims: Diabetes mellitus (DM) has become an increasingly epidemic metabolic disease. Vascular endothelial cells play a key role in developing the cardiovascular complications of DM. The A 2B receptor is expressed in vascular endothelial cells, and may help regulate the function of endothelial cells. The aim of this study was to investigate the protective effects of oxymatrine (OMT) on human umbilical vein endothelial cells (HUVECs) from high glucoseinduced cytotoxicity. Methods: Homology modeling and molecular docking analysis were used to detect the binding sites between the adenosine A 2B receptor and OMT. HUVECs were cultured with control (5.5 mM) or elevated glucose (22.2 mM) in the presence or absence of 3 µM OMT or A 2B siRNA for 3 days. The MTS cell viability assay was used to measure the toxicity of high glucose on HUVECs and the protective effect of OMT or A 2B siRNA. The expression of the adenosine A 2B receptor and CCL5 in HUVECs was detected with real-time quantitative PCR (qPCR) and Western blotting methods in each group. Levels of IL-1β and TNF-α were measured using an enzyme-linked immunosorbent assay (ELISA) kit, and the concentration of NO was detected with the nitrate reductase method. Monocyte chemotactic activity in each group was detected using Transwell chambers. Furthermore, the phosphorylation of p38 and ERK1/2 in each group was observed through the Western blotting method. Results: Homology modeling and molecular docking analysis showed that OMT contains well-fitted binding sites to the A 2B receptor. After chronic culture at high glucose, the rate of cell viability was significantly lower than that of the control group. After co-treatment with OMT or A 2B siRNA, cell viability was significantly increased compared with the high-glucose group. The results from real-time quantitative RT-PCR (qRT-PCR) and Western blotting indicated that high glucose could increase the expression of A 2B receptors in HUVECs, an effect that was inhibited by OMT. In addition, the results revealed that the expression of CCL5, IL-1β and TNF-α was increased in the high-glucose group, and that the NO produced by HUVECs decreased due to hyperglycemia; however, co-culture with OMT or A 2B siRNA abolished these effects. Meanwhile, the chemotaxis activity of monocytes to HUVECs cultured in high-glucose medium was enhanced 2.59-fold compared to the control cells. However, the inflammatory reactions in HUVECs were completely relieved by co-treatment with OMT or A 2B siRNA. Moreover, the phosphorylation of p38 and ERK1/2 in HUVECs in the high-glucose group was significantly higher than that of the control group; these effects were reversed after co-treatment with OMT or A 2B siRNA. Conclusion: OMT may protect the HUVECs from high glucose-induced cytotoxicity through inhibitting the expression of A 2B receptor and inflammatory factors as well as decreasing the phosphorylation of p38 and ERK1/2.

Keap1-Nrf2 signaling activation by Bardoxolone-methyl ameliorates high glucose-induced oxidative injury in human umbilical vein endothelial cells

“…High glucose (HG) treatment in HUVECs can induce robust oxidative injury, responsible for following cell death and apoptosis [ 8 , 28 – 31 ]. Contrarily, antioxidant agents or genetic strategies suppressing oxidative injury can protect HUVECs from HG [ 8 , 28 , 31 ].…”

“…High glucose (HG) treatment in HUVECs can induce robust oxidative injury, responsible for following cell death and apoptosis [ 8 , 28 – 31 ]. Contrarily, antioxidant agents or genetic strategies suppressing oxidative injury can protect HUVECs from HG [ 8 , 28 , 31 ]. We here also found that HG induced potent oxidative stress in HUVECs, leading to superoxide accumulation ( Figure 2A ), GSH reduction (a GSH/GSSG ratio decrease, Figure 2B ) and significant mitochondrial depolarization (green JC-1 monomers accumulation, Figure 2C ), which were largely attenuated by pretreatment of BARD (50 nM, 1h) ( Figure 2A – 2C ).…”

Reduced Growth of Staphylococcus aureus Under High Glucose Conditions Is Associated With Decreased Pentaglycine Expression

“…These data indicate that glucose is essential for the growth of S. aureus. However, high glucose usually induces endothelial and renal cytotoxicity in diabetic patients (Gao et al, 2015;Yi et al, 2018;Liu et al, 2020). S. aureus is the most frequent pathogen isolated from diabetic foot ulcers, but the properties of this bacterium under high glucose conditions remain unclear.…”

Oxymatrine inhibits the pyroptosis in rat insulinoma cells by affecting nuclear factor kappa B and nuclear factor (erythroid-derived 2)-like 2 protein/heme oxygenase-1 pathways

“…Recent studies have demonstrated that oxymatrine is helpful for the treatment of diabetes. In umbilical vein endothelial cells, oxymatrine alleviates high glucose-induced endothelial toxicity by inhibiting ROS production [ 17 , 18 ]. Oxymatrine can reduce the levels of advanced glycation end products, ROS, and inflammatory cytokines in the kidney of diabetic rats [ 19 ].…”