Soft drusen in rhesus macaques as a nonhuman primate model of early age-related macular degeneration

项目摘要 视网膜相关性黄斑变性（AMD）是老年人视力丧失的主要原因，但目前的治疗 针对晚期，此时干预措施可能受到不可逆细胞丢失的限制。软玻璃疣是最初的， AMD是AMD的标志性特征，但其发病机制尚不清楚，治疗的发展受到AMD的局限性。 缺乏良好的动物模型。与大多数实验室动物不同，非人灵长类动物（NHP）拥有真正的黄斑 并自发地形成类似于早期人类AMD的软玻璃疣。先前对NHP玻璃疣的研究 由于维持老年动物的高成本， 纵向成像能力，缺乏下一代测序（NGS）和生物信息学支持。 我们最近在加州国家灵长类动物研究所调查了一个独特的老年恒河猴群体 中心（CNPRC），发现玻璃疣的患病率为30.6%。使用高分辨率多模态体内成像， 我们精确地测量了玻璃疣进展超过2年， 表明脂质积聚类似于人的软玻璃疣。与心血管疾病相似，AMD 流行病学风险因素，如高脂饮食，脂质代谢中的易感基因，以及类似于 动脉粥样硬化斑块伴脂蛋白积聚、脂质氧化和基于补体的炎症 应答最近的初步研究表明，高剂量口服阿托伐他汀可导致玻璃疣消退， AMD患者，但人类研究受到AMD表型异质性和受试者变异性的限制。 饮食和血清脂质浓度。 在这项研究中，我们计划建立一个新的，独特的队列老年恒河猴与软玻璃疣，并执行 1)使用谱域光学相干断层扫描（SD-OCT）进行详细的眼科表征， 精确测量视网膜层并跟踪玻璃疣体积，以及眼底自发荧光（FAF）以测量RPE 脂褐素，2）代谢谱分析，以测量空腹血浆代谢物、脂蛋白和载脂蛋白，和 3)全基因组测序，以确定可能与人类共享的玻璃疣动物的遗传变异 AMD.接下来，我们将确定“西式”高脂/高糖（HFS）饮食和高剂量阿托伐他汀的影响 玻璃疣进展和RPE健康，并确定可能与饮食脂肪和 血脂最后，我们将采用基于NGS的单细胞RNA测序（scRNA-Seq）来确定 有或无软性玻璃疣、暴露于HFS饮食或治疗的黄斑RPE细胞的基因表达谱 用大剂量他汀类药物，然后用对侧眼的免疫组化进行评估和验证， 基因组或途径，以及补体和其他免疫途径。总之，这些研究不会 只建立一个非常有价值和独特的老年恒河猴队列， 翻译研究，但也探讨了饮食脂质，口服他汀类药物，RPE基因表达和免疫的作用， 在早期AMD的NHP模型中，

PROJECT SUMMARY Age-related macular degeneration (AMD) is the leading cause of vision loss in the elderly, but current treatments target advanced stages when interventions may be limited by irreversible cell loss. Soft drusen are the initial and hallmark feature of AMD, but their pathogenesis is unclear and the development of treatments is limited by the lack of good animal models. Unlike most laboratory animals, nonhuman primates (NHPs) possess a true macula and spontaneously develop soft drusen resembling early human AMD. Prior studies of NHP drusen have been observational, cross-sectional, and qualitative, owing to the high costs of maintaining aged animals, limited longitudinal imaging capabilities, and lack of Next-Generation Sequencing (NGS) and bioinformatics support. We recently surveyed a unique colony of geriatric rhesus macaques at the California National Primate Research Center (CNPRC), and found a 30.6% prevalence of drusen. Using high-resolution multimodal in vivo imaging, we precisely measured drusen progression over 2 years, with histological and ultrastructural correlates demonstrating lipid accumulation resembling human soft drusen. Similar to cardiovascular diseases, AMD share epidemiologic risk factors such as high fat diets, susceptibility genes in lipid metabolism, and deposits similar to atherosclerotic plaques with lipoprotein accumulation, lipid oxidation, and complement-based inflammatory responses. Recent pilot studies suggest that high-dose oral atorvastatin can cause drusen regression in some AMD patients, but human studies are limited by the heterogeneity of AMD phenotypes and variability in subject diets and serum lipid concentrations. In this study, we plan to establish a new, unique cohort of aged rhesus macaques with soft drusen, and perform 1) detailed ophthalmic characterization using spectral-domain optical coherence tomography (SD-OCT) to precisely measure retinal layers and track drusen volume, and fundus autofluorescence (FAF) to measure RPE lipofuscin, 2) metabolic profiling to measure fasting plasma metabolites, lipoproteins, and apolipoproteins, and 3) whole-genome sequencing to identify genetic variants in animals with drusen that may be shared with human AMD. Next, we will establish the impact of a “Western-style” high-fat/sugar (HFS) diet and high-dose atorvastatin on drusen progression and RPE health over 2 years, and determine possible correlations with dietary fats and serum lipids. Finally, we will employ NGS-based single-cell RNA-sequencing (scRNA-Seq) to determine the gene expression profile in macular RPE cells with and without soft drusen, exposure to HFS diet, or treatment with high-dose statin, followed by immunohistochemistry of contralateral eyes to evaluate and validate identified gene sets or pathways, as well as complement and other immune pathways. Together, these studies will not only establish a highly-valuable and unique cohort of aged rhesus macaques with soft drusen suitable for translational studies, but also explore the role of dietary lipids, oral statins, RPE gene expression, and immune pathways in this NHP model of early AMD.