Modulation of retinoid reactivity and pathological signaling in retinal therapeutics

视网膜治疗中类维生素A反应性和病理信号的调节

• 批准号: 10618853
• 负责人: Philip David Kiser
• 金额: --
• 依托单位: VETERANS HEALTH ADMINISTRATION
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10618853
• 关键词: 11-cis-Retinol; Age; Age related macular degeneration; Alcohols; Aldehydes; Anabolism; Animal Model; Apoptotic; Binding; Biochemical; Biological; Biology; Blindness; Cell Death; Cells; Ceramides; Chemically Induced Toxicity; Chemicals; Color; Color Visions; Cone; Data; Development; Disease; Disease Progression; Dissociation; Dose; Drug Modulation; Elderly; Enzymes; Esterification; Exhibits; Exposure to; Funding; G Protein-Coupled Receptor Signaling; G-Protein-Coupled Receptors; Goals; Hand; Health; Health Care Costs; Healthcare Systems; High Prevalence; Hour; Human; Image; Imaging Techniques; Individual; Knock-in Mouse; Knock-out; Lead; Light; Link; Lipofuscin; LoxP-flanked allele; Mediating; Mediator; Metabolism; Modeling; Modernization; Muller' s cell; Mus; Natural regeneration; Nonexudative age-related macular degeneration; Opsin; Pathogenesis; Pathologic; Pathway interactions; Pharmaceutical Preparations; Pharmacodynamics; Phosphodiesterase Inhibitors; Photoreceptors; Play; Predisposition; Process; Production; Property; Proteins; RPE65 protein; Reaction; Research; Retina; Retinal Cone; Retinal Diseases; Retinal Pigments; Retinaldehyde; Retinoids; Role; Signal Transduction; Site; Structure; Structure of retinal pigment epithelium; System; Testing; Therapeutic; Therapeutic Agents; Tissues; Toxic effect; Transgenic Mice; Translating; Veterans; Vision; Visual; Visual Perception; Visual impairment; Vitamin A; absorption; adduct; central visual field; chromophore; cis trans isomerization; clinical application; conditional knockout; desaturase; design; dihydroceramide; disability; effective therapy; geographic atrophy; human old age (65+); in vitro testing; in vivo; inhibitor; loss of function; military veteran; mouse model; next generation; novel; novel therapeutics; pharmacologic; phosphoric diester hydrolase; protective effect; rational design; retinol isomerase; single-cell RNA sequencing; small molecule; visual cycle

Project Summary Age-related macular degeneration is a principal cause of vision loss in individuals over the age of 60 years including Veterans. It is characterized by a loss of sight in the central visual field where sharp, polychromatic images are generated under the bright light conditions that modern humans are typically exposed to during waking hours. Loss of this high acuity color vision leads to significant disability. The high prevalence of AMD places a large burden on the healthcare system with upwards of 98 billion dollars spent yearly on AMD-related healthcare costs in the US. Currently, there are no highly effective treatments for the most common form of the disease, known as geographic atrophy, which makes up ~90% of advanced AMD. During the past VA funding period, we studied inhibition of the visual cycle as a potential treatment for AMD and characterized enzymes proposed to contribute to the normal function of the visual cycle pathway. Based on key findings we made during the initial funding period, we now propose to investigate related pathways that are tied to the pathogenesis of AMD through the involvement of retinaldehyde (RAL) derived from the visual cycle. Additionally, we will continue our studies on an enzyme known as Des1 that has been proposed to mediate the regeneration of cone visual pigments, the color sensing molecules in the central retina. We will explore these pathways through the following Specific Aims: 1. Elucidate biological roles for Des1 within the RPE using novel RPE- specific Cre mice. Previously, we showed that Des1 protein in Müller cells is not a major contributor to 11-cis- retinol synthesis for cone photoreceptors. However, single cell RNA-Seq analysis revealed that the RPE is the principal site of Des1 expression in the retina raising questions about its biological role in this tissue. Using a validated floxed Des1 mouse model, we will investigate the impact of Des1 loss of function on RPE and photoreceptor health and visual cycle function by crossing these mice with RPE-specific Cre mice and characterizing them using a variety of functional and imaging techniques. Des1 also plays a key role in de novo ceramide production, a known mediator of apoptotic RPE cell death. We hypothesize that Des1 deletion in the RPE will modulate susceptibility of the tissue to chemical-induced toxicity, which serves as a model for RPE cell death that occurs in geographic atrophy. These studies will test the viability of Des1 as a potential target for AMD therapeutics. 2. Advance next-generation visual cycle modulators (VCMs) with selective pharmacodynamics. Visual cycle modulators were originally designed to inhibit RPE65 in order to suppress pathological lipofuscin accumulation and slow retinal disease progression. We discovered a novel mechanism of action for these compounds: direct reaction with RAL released from activated visual opsins to limit formation of pathological RAL adducts. We have generated visual cycle modulators with preferential activity towards RAL sequestration that possess protective effects against retinopathy with reduced effects on visual cycle activity. Based on our initial studies, we propose to synthesize and characterize a new set of rationally-designed visual cycle modulators that we hypothesize will possess augmented therapeutic activity and diminished visual cycle suppression. 3. Develop phosphodiesterase (PDE) inhibition as a treatment for retinal disease. Prior research has implicated aberrant GPCR signaling in RAL toxicity. Phosphodiesterase enzymes are major effectors and regulators of GPCRs and have been successfully targeted for clinical applications. We hypothesize that inhibitors of PDEs will confer protective effects against retinal insults without impairing visual function. Our preliminary data indicates that PDE4 inhibitors are particularly effective at low doses in animal models of RAL toxicity. We will screen these compounds and related derivatives to elucidate their site and mechanism of protective action using animal models of retinopathy. Together, these studies may uncover small molecules that could readily be translated into retinal disease treatments for veterans.

项目摘要 与年龄相关的黄斑变性是60岁以上个体视力丧失的主要原因 包括退伍军人。它的特征是在中央视野中失去视线，锋利的多色调 图像是在现代人类通常暴露在明亮的光条件下产生的 醒来的时间。这种高敏度色彩视觉的丧失会导致严重的残疾。 AMD的高流行率 在医疗保健系统上烧毁了大量烧毁，在与AMD有关的一年中花费了980亿美元 美国的医疗保健费用。目前，对于最常见的形式没有高度有效的治疗方法 疾病，称为地理萎缩，占晚期AMD的90％。在过去的VA资金中 时期，我们研究了视觉周期的抑制作用，作为对AMD的潜在治疗方法和表征酶 提议有助于视觉周期途径的正常功能。根据我们在 最初的资金期，我们现在建议研究与相关的途径，这些途径与 通过从视觉循环中得出的视网膜醛（RAL）参与。此外，我们会的 继续我们对称为DES1的酶的研究，该酶已提出介导锥体的再生 视觉颜料，中央视网膜中的颜色传感分子。我们将通过 以下具体目的：1。使用新型的RPE-阐明RPE中DES1的生物学作用 特定的Cre小鼠。以前，我们表明müller细胞中的DES1蛋白并不是11-CIS-的主要因素 锥光受体的视黄醇合成。但是，单细胞RNA-seq分析表明RPE是 DES1表达在视网膜中的主要部位提出了有关其在该组织中生物学作用的问题。使用 经过验证的Floxed DES1小鼠模型，我们将研究DES1功能丧失对RPE的影响 光感受器的健康和视觉周期功能通过将这些小鼠与RPE特异性的Cre小鼠交叉和 使用各种功能和成像技术来表征它们。 DES1在从头上也起着关键作用 神经酰胺的生产，是凋亡RPE细胞死亡的已知介质。我们假设在 RPE将调节组织对化学诱导的毒性的敏感性，该毒性是RPE细胞的模型 地理萎缩中发生的死亡。这些研究将测试DES1作为AMD的潜在目标的生存能力 治疗。 2。提前下一代视觉周期调制器（VCM）具有选择性 药效学。视觉周期调节器最初设计用于抑制RPE65，以抑制 病理脂肪霉素积累和视网膜疾病进展缓慢。我们发现了一种新颖的机制 这些化合物的作用：与从激活的视觉视觉蛋白释放的RAL的直接反应，以限制形成 病理性的加合物。我们已经生成了具有对RAL的优先活动的视觉循环调制器 对视网膜病具有保护作用，对视网膜病的影响有所降低，对视觉周期活动的影响降低。 根据我们的初步研究，我们建议合成并表征一组新的合理设计的视觉 我们假设的循环调节器将具有增强的治疗活性并减少视觉周期 抑制。 3。发展磷酸二酯酶（PDE）作为残留疾病的治疗方法。 先前的研究已经在RAL毒性中实现了异常的GPCR信号传导。磷酸二酯酶是主要的 GPCR的效应子和调节剂已成功地针对临床应用。我们假设 PDE的抑制剂将在不损害视觉功能的情况下会受到保护的影响。 我们的初步数据表明，PDE4抑制剂在低剂量的动物模型中特别有效 RAL毒性。我们将筛选这些化合物和相关的衍生物，以阐明其位置和机制 使用视网膜病变动物模型的保护作用。总之，这些研究可能会发现小分子 很容易将其转化为退伍军人的残留疾病治疗。