Peroxide, NO and Iron Signaling in Endothelial Damage

内皮损伤中的过氧化物、NO 和铁信号传导

• 批准号: 7024476
• 负责人: BALARAMAN KALYANARAMAN
• 金额: $ 29.3万
• 依托单位: MEDICAL COLLEGE OF WISCONSIN
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-03-17 至 2008-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7024476
• 关键词: antioxidants; apoptosis; cardiovascular injury; cell line; enzyme inhibitors; fluorescent dye /probe; glutathione; immunologic assay /test; iron metabolism; lipid peroxides; nitric oxide; nitric oxide synthase; oxidative stress; oxidized lipid; peroxides; receptor expression; tissue /cell culture; transferrin receptor; vascular endothelium

DESCRIPTION (provided by applicant): Long-term goal: The long-term goal of this proposal is to unravel the role of oxidant-induced iron signaling mechanism in endothelial cell apoptosis. Emerging studies indicate that the cellular oxidative damage caused by reactive oxygen and nitrogen species (ROS/RNS) is critically controlled by cellular iron homeostasis. Hypothesis: The general hypotheses to be tested are that (i) peroxide (e.g., H2O2, lipid hydroperoxide)-induced endothelial oxidative damage and apoptosis are mediated by transferrin receptor (TfR)-dependent uptake of transferrin (Tf)-iron and that the TfR is an effective "gatekeeper" and modulator of oxidant-induced apoptosis in endothelial cells, and (ii) nitric oxide (NO) and antioxidants mitigate peroxide-induced endothelial damage by inhibiting iron signaling mechanism. Specific aims: First, we will investigate the effect of extracellular and intracellular hydroperoxides on endothelial iron signaling and apoptosis. Next, we will investigate the effect of cell-permeable esterase-specific NO donors and NO synthase inhibitors on peroxide-induced iron signaling and apoptosis. The objective here will be to establish the link between iron, oxidative/nitrosative stress, and peroxide-induced endothelial toxicity. Finally, we will investigate the effect of antioxidant (enzyme) supplementation on peroxide-induced intracellular oxidative stress, iron signaling, and apoptosis. Methods: We will use the bovine aortic endothelial cells (BAEC) and human aortic endothelial cells (HAEC). The following redox- parameters will be measured: GSH and lipid peroxides; aconitase and iron-regulatory protein activities; TfR expression, 55Fe uptake; caspase signaling, and apoptosis. Superoxide and hydroxyl radicals will be determined by fluorescence and novel spin-trapping (immunoassay) techniques. Significance: Endothelial cell injury is an early oxidative insult in many cardiovascular diseases. Several clinical and basic research studies implicated a role for oxidant-induced iron signaling in vascular oxidative damage. Novelty: This proposal presents a new insight on peroxide-induced iron signaling in endothelial apoptosis and on the role of NO and antioxidants in mitigating these effects.

描述（由申请人提供）：长期目标：本提案的长期目标是阐明氧化诱导的铁信号机制在内皮细胞凋亡中的作用。新的研究表明，活性氧和活性氮（ROS/RNS）引起的细胞氧化损伤是由细胞铁稳态控制的。假设：需要验证的一般假设是：(i)过氧化氢（如H2O2、脂质氢过氧化氢）诱导的内皮细胞氧化损伤和凋亡是由转铁蛋白受体（TfR）依赖的转铁蛋白（Tf）铁摄取介导的，TfR是氧化诱导的内皮细胞凋亡的有效“守门者”和调节剂；（ii）一氧化氮（NO）和抗氧化剂通过抑制铁信号传导机制减轻过氧化氢诱导的内皮细胞损伤。具体目的：首先，我们将研究细胞外和细胞内氢过氧化物对内皮铁信号传导和细胞凋亡的影响。接下来，我们将研究细胞渗透性酯酶特异性NO供体和NO合酶抑制剂对过氧化物诱导的铁信号传导和细胞凋亡的影响。这里的目的将是建立铁，氧化/亚硝化应激和过氧化物诱导的内皮毒性之间的联系。最后，我们将探讨补充抗氧化剂（酶）对过氧化物诱导的细胞内氧化应激、铁信号传导和细胞凋亡的影响。方法：采用牛主动脉内皮细胞（BAEC）和人主动脉内皮细胞（HAEC）。测量以下氧化还原参数：谷胱甘肽和脂质过氧化物；乌头酶和铁调节蛋白活性；TfR表达，55Fe摄取；Caspase信号和细胞凋亡。超氧化物和羟基自由基将通过荧光和新的自旋捕获（免疫测定）技术来测定。意义：内皮细胞损伤是许多心血管疾病的早期氧化损伤。一些临床和基础研究暗示了氧化诱导的铁信号在血管氧化损伤中的作用。新颖性：这一提议提出了一个新的见解，在内皮细胞凋亡和一氧化氮和抗氧化剂在减轻这些影响中的作用的过氧化物诱导铁信号。