کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2573942 1561239 2016 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Lack of glutathione peroxidase-1 facilitates a pro-inflammatory and activated vascular endothelium
ترجمه فارسی عنوان
کمبود گلوتاتیون پراکسیداز-1 تسهیل کننده اندوتلیوم عروقی طرفدار التهابی و فعال
کلمات کلیدی
موضوعات مرتبط
علوم پزشکی و سلامت پزشکی و دندانپزشکی کاردیولوژی و پزشکی قلب و عروق
چکیده انگلیسی

A critical early event in the pathogenesis of atherosclerosis is vascular inflammation leading to endothelial dysfunction (ED). Reactive oxygen species and inflammation are inextricably linked and declining antioxidant defense is implicated in ED. We have previously shown that Glutathione peroxidase-1 (GPx1) is a crucial antioxidant enzyme in the protection against diabetes-associated atherosclerosis. In this study we aimed to investigate mechanisms by which lack of GPx1 affects pro-inflammatory mediators in primary aortic endothelial cells (PAECs) isolated from GPx1 knockout (GPx1 KO) mice. Herein, we demonstrate that lack of GPx1 prolonged TNF-α induced phosphorylation of P38, ERK and JNK, all of which was reversed upon treatment with the GPx1 mimetic, ebselen. In addition, Akt phosphorylation was reduced in GPx1 KO PAECs, which correlated with decreased nitric oxide (NO) bioavailability as compared to WT PAECs. Furthermore, IκB degradation was prolonged in GPx1 KO PAECS suggesting an augmentation of NF-κB activity. In addition, the expression of vascular cell adhesion molecule (VCAM-1) was significantly increased in GPx1 KO PAECs and aortas. Static and dynamic flow adhesion assays showed significantly increased adhesion of fluorescently labeled leukocytes to GPx1 KO PAECS and aortas respectively, which were significantly reduced by ebselen treatment. Our results suggest that GPx1 plays a critical role in regulating pro-inflammatory pathways, including MAPK and NF-κB, and down-stream mediators such as VCAM-1, in vascular endothelial cells. Lack of GPx1, via effects on p-AKT also affects signaling to eNOS-derived NO. We speculate based on these results that declining antioxidant defenses as seen in cardiovascular diseases, by failing to regulate these pro-inflammatory pathways, facilitates an inflammatory and activated endothelium leading to ED and atherogenesis.

Proposed model demonstrating pathways that lead to endothelial dysfunction in the absence of GPx1. In response to pro-inflammatory cytokines (TNF-α), there is an increase in ROS production in GPx1 KO endothelial cells, which lead to the phosphorylation and activation of MAPK and NFκB pathways and VCAM-1 induction. In addition, Akt phosphorylation, eNOS phosphorylation and subsequently NO bioavailability is reduced. Collectively, this leads to endothelial dysfunction which promotes leukocyte-endothelial interactions.Figure optionsDownload high-quality image (144 K)Download as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Vascular Pharmacology - Volume 79, April 2016, Pages 32–42
نویسندگان
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