Regulation of blood-retina barrier by placental growth factor

胎盘生长因子对血视网膜屏障的调节

基本信息

批准号：
10133079
负责人：
Hu Huang
金额：
$ 35.84万
依托单位：
UNIVERSITY OF MISSOURI-COLUMBIA
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-04-01 至 2022-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10133079
关键词：
ANGPT1 gene Address Adhesions Angiopoietin-2 Antibodies Antioxidants Apoptosis Background Diabetic Retinopathy Binding Blindness Blood Glucose Blood-Retinal Barrier Cattle Cell Culture Techniques Cells Clinical Research Complications of Diabetes Mellitus Conditioned Culture Media Diabetes Mellitus Diabetic Retinopathy Diabetic mouse Dimerization Dominant-Negative Mutation Electrical Resistance Endothelial Cells Endothelial Growth Factors Receptor Equilibrium Event Extravasation Family Functional disorder Gene Silencing Glucose Glutathione S-Transferase P Growth Factor Gene Growth Factor Inhibition Heterodimerization Human Hypoglycemia Immunoglobulin G In Vitro Incubated Insulin KDR gene Knockout Mice Ligands Mannitol Measurement Measures Mediating Monoclonal Antibodies Mus NF-kappa B Nuclear Oxidative Stress PF4 Gene PGF gene Pathologic Patients Pericytes Permeability Pharmaceutical Preparations Phosphorylation Point Mutation Pregnancy Proteins Production Property Proteins Receptor Signaling Regulation Retina Role SHH gene Signal Transduction Site-Directed Mutagenesis Small Interfering RNA Testing Time Tyrosine Up-Regulation Variant Vascular Endothelial Growth Factor B Vascular Endothelial Growth Factors Visual impairment activating transcription factor adeno-associated viral vector base cadherin 5 cell type cytokine design diabetic dimer electric impedance fluorescein isothiocyanate dextran in vivo intravitreal injection macular edema member monolayer oxidative damage paracrine peroxiredoxin prevent protein expression receptor function receptor-mediated signaling small hairpin RNA success

项目摘要

Project Summary Diabetic retinopathy (DR) is a leading cause of vision loss and impairment worldwide. Diabetic macular edema (DME) as a result of blood-retinal barrier (BRB) breakdown is a major complication of DR leading to blindness. Despite the success of anti-vascular endothelial growth factor (VEGF) therapy on DME, little is known about placental growth factor (PlGF)'s functional role in BRB breakdown in DR. PlGF, a member of the VEGF sub- family, is a multifunctional cytokine with pathological angiogenic properties. Recent studies highlight PlGF's role in BRB breakdown in DME. We recently showed that PlGF knockout (KO) mice were protected from diabetes- caused BRB breakdown by upregulating several protective proteins. Emerging clinical studies showed that the drug aflibercept, which blocks both PlGF and VEGF, prevented BRB breakdown in DME patients. Despite these recent advances several questions remain to be addressed. 1) Is selective PlGF inhibition sufficient to prevent diabetes-caused BRB breakdown? 2) What is the cell type-specific effect on BRB function by targeting PlGF? 3) Does PlGF regulate BRB by mechanisms distinct from VEGF? 4) Are there interactions between PlGF and VEGF (PlGF-VEGF heterodimers) that together contribute to BRB breakdown in DR? 5) What is the role of VEGF receptor (VEGFR1) signaling in the regulation of human retinal endothelial cell (HREC) barrier function? The answers to these important questions will better define PlGF's causal role in diabetes-induced BRB breakdown that will lead to the design of better precision-targeted treatments for DME patients. Therefore, the objective of this proposal is to address these questions. Our overall hypothesis is that targeting PlGF prevents diabetes-caused BRB breakdown via upregulation of protective proteins, disruption of PlGF-VEGF dimers, and inactivation of VEGFR1 in pericyte. Three specific aims are proposed to test the hypothesis. Aim-1 is to determine the role of key survival or antioxidant proteins in BRB protection by targeting PlGF in DR. Small hairpin (sh) RNA and monoclonal antibody will silence or block PlGF in vivo or in vitro. The BRB protection by survival or antioxidant proteins will be elucidated with HREC culture. Aim-2 is to determine the contribution of PlGF-VEGF heterodimers on BRB breakdown in DR. PlGF KO mice will be used to determine if PlGF is essential for DR-like features by VEGF. Insulin will treat diabetic mice to determine if hypoglycemia induces PlGF-VEGF dimerization. A dominant-negative PlGF variant, which can heterodimerize with VEGF but not bind VEGFR1, will determine the role of PlGF-VEGF in diabetes-induced BRB breakdown. Aim-3 is to determine the role of VEGFR1 signaling in pericyte and its role in paracrine regulation of BRB function. The proposed paracrine mechanism(s) will be deciphered: pericyte VEGFR1 signaling cascades triggered by high glucose (HG) leads to upregulation of VEGF, PlGF, and/or VEGF-B expression and induction of VEGFR1 phosphorylation or activation events that mediate HG-induced pericyte apoptosis (via nuclear factor (NF)-ĸB). The damaged pericytes contribute to retinal EC barrier dysfunction by disrupting the balance between Angiopoietin (Ang)-1 and Ang-2.

项目概要糖尿病视网膜病变 (DR) 是全世界视力丧失和损害的主要原因。血视网膜屏障 (BRB) 破坏导致的 DME（DME）是 DR 导致失明的主要并发症。尽管抗血管内皮生长因子 (VEGF) 治疗 DME 取得了成功，但人们对它知之甚少。胎盘生长因子 (PlGF) 在 DR 中 BRB 分解中的功能作用，PlGF 是 VEGF 亚组的成员。 PlGF 家族是一种具有病理性血管生成特性的多功能细胞因子。在 DME 中的 BRB 分解中，我们最近表明 PlGF 敲除 (KO) 小鼠可以免受糖尿病的侵害。新兴的临床研究表明，通过上调几种保护性蛋白导致 BRB 分解。药物阿柏西普可阻断 PlGF 和 VEGF，防止 DME 患者的 BRB 分解。这些最新进展仍有几个问题有待解决：1) 选择性 PlGF 抑制是否足以解决这一问题。预防糖尿病引起的 BRB 分解？ 2) 通过靶向作用对 BRB 功能的细胞类型特异性影响是什么？ PlGF？3) PlGF 是否通过与 VEGF 不同的机制调节 BRB？ PlGF 和 VEGF（PlGF-VEGF 异二聚体）共同导致 DR 中的 BRB 分解？ VEGF 受体 (VEGFR1) 信号在人视网膜内皮细胞 (HREC) 屏障调节中的作用这些重要问题的答案将更好地确定 PlGF 在糖尿病诱发中的因果作用 BRB 的分解将导致为 DME 患者设计更好的精准靶向治疗。该提案的目的是解决这些问题，我们的总体假设是针对 PlGF。通过上调保护性蛋白、破坏 PlGF-VEGF 来预防糖尿病引起的 BRB 分解提出了三个具体目标来检验 Aim-1 的假设。旨在通过靶向 DR Small 中的 PlGF 来确定关键存活蛋白或抗氧化蛋白在 BRB 保护中的作用。发夹（sh）RNA和单克隆抗体会在体内或体外沉默或阻断PlGF对BRB的保护。存活或抗氧化蛋白将通过 HREC 培养来阐明，目的是确定 Aim-2 的贡献。 PlGF KO 小鼠中 BRB 分解的 PlGF-VEGF 异二聚体将用于确定 PlGF 是否有效。 VEGF 的 DR 样特征至关重要。胰岛素将治疗糖尿病小鼠，以确定是否会诱发低血糖。 PlGF-VEGF 二聚化。显性失活的 PlGF 变体，可以与 VEGF 异二聚化，但不结合。 VEGFR1 将确定 PlGF-VEGF 在糖尿病诱导的 BRB 分解中的作用 Aim-3 是确定的。 VEGFR1 信号在周细胞中的作用及其在 BRB 功能旁分泌调节中的作用。旁分泌机制将被破译：高葡萄糖触发周细胞 VEGFR1 信号级联 (HG) 导致 VEGF、PlGF 和/或 VEGF-B 表达上调并诱导 VEGFR1 介导 HG 诱导的周细胞凋亡的磷酸化或激活事件（通过核因子 (NF)-ĸB）。受损的周细胞会破坏视网膜 EC 屏障之间的平衡，从而导致视网膜 EC 屏障功能障碍。血管生成素 (Ang)-1 和 Ang-2。