Targeting peptide Lv and its downstream signaling against ocular neovascularization

靶向肽 Lv 及其下游信号对抗眼部新生血管形成

基本信息

批准号：
10407598
负责人：
GLADYS Y KO
金额：
$ 21.62万
依托单位：
TEXAS A&M UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-06-01 至 2024-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10407598
关键词：
Age related macular degeneration Angiogenic Factor Angiogenic Peptides Animal Model Antibodies Binding Biological Assay Blindness Blood Vessels Blood flow Calcium Cell Proliferation Choroidal Neovascularization Chronic Clinical Data Development Disease Endothelial Cells Endothelial Growth Factors Receptor Endothelium Extravasation Family Future Genetic Goals In Vitro Incidence KDR gene Knock-out Knowledge L-Type Calcium Channels Lasers Lead Mediating Messenger RNA Mission Molecular Mus Muscle Cells Nitric Oxide Nitric Oxide Synthetase Inhibitor Oxygen Pathogenesis Pathologic Pathologic Neovascularization Patients Peptides Pharmacology Photoreceptors Pilot Projects Potassium Channel Prevention Property Recurrence Research Resistance Retina Retinal Detachment Retinal Diseases Role Sequence Homology Signal Transduction Smooth Muscle Testing Therapeutic Treatment Factor United States National Institutes of Health Vascular Diseases Vascular Endothelial Cell Vascular Endothelial Growth Factors Vascular Permeabilities Vasodilation Vasodilator Agents Veins angiogenesis arteriole combat in vivo member migration mouse model mutant neovascular neovascularization novel ocular angiogenesis ocular neovascularization proliferative diabetic retinopathy protein expression resistance mechanism side effect tool

项目摘要

Project Summary Anti-vascular endothelial growth factor (VEGF) therapies are widely used for treating ocular diseases with neovascularization, but nearly 30% of afflicted patients are non-responders to anti-VEGF agents. In addition, repetitive anti-VEGF treatments that are needed to block the recurring neovascularization often lead to unintended side-effects including retinal detachment and even blindness. Thus, searching for VEGF-independent angiogenic factors and unveiling their underlying mechanisms become an imperative clinical need to help combat the recurrence of neovascularization and the resistance to anti-VEGFs in these diseases. Peptide Lv is a newly discovered angiogenic peptide that is upregulated in the retinas of patients with early proliferative diabetic retinopathy (PDR) and of mice subjected to oxygen-induced retinopathy (OIR), featuring ocular pathological neovascularization. Although it has no sequence homology to members of the VEGF family and VEGF receptors (VEGFRs), peptide Lv promotes angiogenesis in vitro and in vivo. An antibody against peptide Lv, anti-Lv, not only dampens VEGF- elicited endothelial cell proliferation, it also effectively blocks pathological neovascularization in mice with OIR, as well as laser-induced choroidal neovascularization. Furthermore, peptide Lv not only cooperatively promotes VEGF-induced angiogenesis, but also elicits VEGF/VEGFR2/nitric oxide-independent vasodilation. Chronic vasodilation of existing vessels causes increased vascular permeability, stimulates angiogenesis, and promotes neovascularization. Vasodilators are associated with a ~70% increased incidence of early age-related macular degeneration (AMD). Thus, peptide Lv might be involved in the pathogenesis of PDR and wet AMD via promoting both VEGF/VEGFR2-dependent and -independent angiogenesis and vasodilation. However, the mechanistic role of peptide Lv in mediating VEGF-independent angiogenesis and vasodilation is completely unknown. Peptide Lv is able to augment the protein expression of intermediate conductance calcium-dependent potassium channels (IKCa) in cultured endothelial cells. Activation of K+ channels in the endothelium, especially IKCa, is important in angiogenesis that can be VEGF/VEGFR2-independent. Opening these K+ channels can also lead to VEGF-independent vasodilation. Herein, the objective is to unveil novel cellular mechanisms of peptide Lv in VEGF/VEGFR2- independent angiogenesis and vasodilation. The central hypothesis is that peptide Lv activates and augments IKCa in retinal endothelial cells that consequently leads to VEGF/VEGFR2-independent angiogenesis and vasodilation, the underlying mechanism of resistance to anti-VEGFs. Two Aims combining in vitro, ex vivo, and in vivo approaches to decipher peptide Lv-IKCa axis in VEGF/VEGFR2-independent angiogenesis and vasodilation will be carried out by using peptide Lv null (peptide Lv-/-), IKCa null (Kcnn4-/-), and vascular endothelial cell-specific knockout of VEGFR2 (VEGFR2iΔEC) mice. Completion of the proposed research will unveil new mechanisms of peptide Lv in VEGF/ VEGFR2-independent angiogenesis and vasodilation, which will have a direct impact on the future development of blocking peptide Lv-downstream targets as a therapeutic tool against ocular pathological neovascularization.

项目摘要抗血管内皮生长因子（VEGF）疗法广泛用于治疗眼部疾病新血管形成，但近30％的患者是抗VEGF药物的无反应者。此外，阻止重复发生的新生血管形成所需的重复抗VEGF治疗通常会导致意外副作用，包括残留分离甚至失明。那是寻找独立于VEGF的血管生成的因素并揭示其潜在机制成为有助于应对复发的急需临床需求这些疾病中的新血管形成和对抗VEGF的抗性。肽LV是新发现的早期增殖性视网膜病（PDR）患者的视网膜中上调的血管生成胡椒以及受氧诱导的视网膜病变（OIR）的小鼠，具有眼病理新生血管形成。尽管它与VEGF家族和VEGF受体（VEGFRS）的成员没有序列同源性，但Peppered LV 在体外和体内促进血管生成。抗肽LV抗LV的抗体，不仅会抑制VEGF- 引起内皮细胞增殖，它还有效地阻止了OIR小鼠的病理新生血管化，以及激光诱导的脉络膜新血管形成。此外，胡椒LV不仅合作促进 VEGF诱导的血管生成，但也引起VEGF/VEGFR2/一氧化氮非依赖性血管舒张。慢性的现有血管的血管舒张会导致血管通透性增加，刺激血管生成并促进新血管形成。血管扩张剂与早年相关黄斑的发病率增加约70％变性（AMD）。这是通过促进参与PDR和湿AMD的发病机理的辣椒lv VEGF/VEGFR2依赖性和非依赖性血管生成和血管舒张。但是，机械作用介导不依赖VEGF的血管生成和血管舒张中的肽LV是完全未知的。肽LV是可以增加中间电导钙依赖性钾通道（IKCA）的蛋白质表达在培养的内皮细胞中。内皮中K+通道的激活，尤其是IKCA，在血管生成中很重要这可以是vegf/vegfr2无关的。打开这些K+通道也可能导致无关紧要的血管舒张。在此，目的是揭示VEGF/VEGFR2-肽LV的新型细胞机制独立的血管生成和血管舒张。中心假设是肽LV激活和增强IKCA 在永久性内皮细胞中，导致VEGF/VEGFR2独立的血管生成和血管舒张，对抗VEGF的抗性的基本机制。两个目的在体外结合，离体和体内方法在VEGF/VEGFFR2非依赖性的血管生成和血管舒张中，将通过肽LV-IKCA轴破译。使用Pepperide LV Null（肽LV-/ - ），IKCA NULL（KCNN4 - / - ）和VEGFR2的血管内皮细胞特异性敲除（VEGFR2IΔEC）小鼠。拟议研究的完成将揭示VEGF/肽LV的新机制无关VEGFR2的血管生成和血管舒张，这将直接影响未来的发展阻止肽LV下游靶标作为针对眼病理新生血管形成的治疗工具。