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Mechanisms for Arsenic-Induced Vascular Disease

砷诱发血管疾病的机制

基本信息

批准号：
8197518
负责人：
Aaron Barchowsky
金额：
$ 32.88万
依托单位：
UNIVERSITY OF PITTSBURGH AT PITTSBURGH
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-12-14 至 2012-11-30
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): Chronic exposure to trivalent arsenic (As III) is well known to cause cardiovascular diseases. In the human liver, As (III) promotes vascular remodeling, portal fibrosis, and hypertension, but the molecular pathophysiology of these As III-induced vascular changes is unknown. In general, the pathogenesis of As III induced vascular diseases has been understudied, in part, due to a lack of relevant animal models sensitive to chronic low dose As III effects. Our preliminary results show that exposure of intact adult mice to as low as 10 ppb of As III in their drinking water caused defenestration and capillarization of liver sinusoidal endothelium (LSEC). Furthermore, we also show that primary, short term cultures of murine or human LSEC are useful in revealing functional roles for As (III)-stimulated NADPH oxidase (NOX) generation of reactive oxygen species in the early signaling events affecting phenotype (e.g. fenestration) of this important target cell. The objective of the proposed studies is to use these in vivo and ex vivo models to investigate the mechanisms through which As (III) initiates LSEC remodeling and the molecular pathology of As (III)-induced vascular diseases. The global hypothesis for these studies states that As (III) acts at the level of g-protein coupled cell signaling to promote NOX oxidant generation that disrupts maintenance of LSEC fenestrations and suppression of capillarization. Accordingly, the specific aims of this proposal are to determine: I. the molecular mechanism by which As (III) causes liver sinusoidal capillarization and remodeling in intact mice. Wildtype and NOX deficient (p47phox -/-) mice will be exposed to As (III) (10-50 ppb) for 2 weeks and morphometric (light and electron microscopic level) determinants of SEC defenestration and capillarization will be quantified. Pharmacologically (antibodies to vascular endothelial cell growth factor receptor or Pertussis toxin) modified mice will be used to assess the contribution VEGF receptor and Gi-protein linked signaling to As III-induced vascular changes. II. the role of NOX generated superoxide in mediating As III-induced phenotypic conversion of primary murine and human LSEC. LSEC isolated from human liver or wildtype and p47phox -/- mice will be exposed to As (III) ex vivo to demonstrate mechanisms through which an imbalance of reactive oxygen and nitrogen species generation mediates AsIII-dysregulation of VEGF receptor maintained LSEC fenestration. III. if an imbalance in LSEC GT Pase activity mediates As (III) stimulated remodeling of the LSEC. Targeted delivery of RhoA or Rac1-GTPase siRNA and selective GT Pase activity assays will be used to dissect the roles of Rho family members in As (III)-stimulated LSEC capillarization.

描述(由申请人提供)：众所周知，长期接触三价砷(AS III)会导致心血管疾病。在人类肝脏中，As(III)促进血管重塑、门脉纤维化和高血压，但这些As(III)诱导的血管变化的分子病理生理学尚不清楚。总体而言，As III诱导的血管疾病的发病机制一直没有得到充分的研究，部分原因是缺乏对慢性低剂量As III效应敏感的相关动物模型。我们的初步结果显示，正常成年小鼠在饮用水中暴露于低至10 ppb的As III时，可导致肝窦内皮细胞(LSEC)去窗和毛细化。此外，我们还表明，小鼠或人LSEC的原代短期培养有助于揭示As(III)刺激的NADPH氧化酶(NOX)在影响这一重要靶细胞表型(例如窗口)的早期信号事件中的功能作用。本研究的目的是利用这些体内和体外模型来研究As(III)启动LSEC重塑的机制和As(III)诱导的血管疾病的分子病理学。这些研究的全球假说表明，As(III)作用于g蛋白偶联细胞信号水平，促进NOX氧化剂的产生，从而扰乱LSEC窗口的维持和抑制毛细血管形成。因此，这项建议的具体目的是确定：1.砷(III)导致完整小鼠肝窦毛细血管形成和重塑的分子机制。野生型和NOX缺陷(p47Phox-/-)小鼠将暴露于As(III)(10-50 ppb)2周，并将量化SEC窗口和毛细血管形成的形态计量学(光镜和电子显微镜水平)决定因素。药理学上(抗血管内皮细胞生长因子受体抗体或百日咳毒素)修饰的小鼠将被用来评估血管内皮生长因子受体和Gi蛋白在AS III诱导的血管变化中的作用。2.NOX产生的超氧化物在介导AS III诱导原代小鼠和人LSEC表型转换中的作用。从人肝或野生型和p47Phox-/-小鼠分离的LSEC将在体外暴露于As(III)，以揭示活性氧和氮物种生成失衡介导AsIII-维持LSEC窗口的血管内皮生长因子受体调节失调的机制。III.如果LSEC GT Pase活性失衡介导AS(Iii)刺激LSEC重构。RhoA或rac1-GTPase siRNA的靶向传递和选择性GT Pase活性分析将被用来分析Rho家族成员在As(III)刺激的LSEC毛细血管形成中的作用。

项目成果

期刊论文数量（8）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Arsenic induces sustained impairment of skeletal muscle and muscle progenitor cell ultrastructure and bioenergetics.

DOI：
10.1016/j.freeradbiomed.2014.06.012
发表时间：
2014-09
期刊：
FREE RADICAL BIOLOGY AND MEDICINE
影响因子：
7.4
作者：
Ambrosio, Fabrisia;Brown, Elke;Stolz, Donna;Ferrari, Ricardo;Goodpaster, Bret;Deasy, Bridget;Distefano, Giovanna;Roperti, Alexandra;Cheikhi, Amin;Garciafigueroa, Yesica;Barchowsky, Aaron
通讯作者：
Barchowsky, Aaron

Erratum to: Arsenic Promotes NF-Κb-Mediated Fibroblast Dysfunction and Matrix Remodeling to Impair Muscle Stem Cell Function.

勘误表：砷促进 NF-β 介导的成纤维细胞功能障碍和基质重塑，从而损害肌肉干细胞功能。