Gao Fangyuan, Tom Emily, Rydz Cezary, Cho William, Kolesnikov Alexander V, Sha Yutong, Papadam Anastasios, Jafari Samantha, Joseph Andrew, Ahanchi Ava, Saraei Nika Balalaei Someh, Lyon David, Foik Andrzej, Nie Qing, Grassmann Felix, Kefalov Vladimir J, Skowronska-Krawczyk Dorota
Gavin Herbert Eye Institute - Center for Translational Vision Research, Department of Ophthalmology, University of California Irvine, CA, 92697, USA.
Department of Physiology and Biophysics, School of Medicine, University of California Irvine, CA.
bioRxiv. 2024 Jul 2:2024.07.01.601592. doi: 10.1101/2024.07.01.601592.
The retina is uniquely enriched in polyunsaturated fatty acids (PUFAs), which are primarily localized in cell membranes, where they govern membrane biophysical properties such as diffusion, permeability, domain formation, and curvature generation. During aging, alterations in lipid metabolism lead to reduced content of very long-chain PUFAs (VLC-PUFAs) in the retina, and this decline is associated with normal age-related visual decline and pathological age-related macular degeneration (AMD). (Elongation of very-long-chain fatty acids-like 2) encodes a transmembrane protein that produces precursors to docosahexaenoic acid (DHA) and VLC-PUFAs, and methylation level of its promoter is currently the best predictor of chronological age. Here, we show that mice lacking ELOVL2-specific enzymatic activity ( ) have impaired contrast sensitivity and slower rod response recovery following bright light exposure. Intravitreal supplementation with the direct product of ELOVL2, 24:5n-3, in aged animals significantly improved visual function and reduced accumulation of ApoE, HTRA1 and complement proteins in sub-RPE deposits. At the molecular level, the gene expression pattern observed in retinas supplemented with 24:5n-3 exhibited a partial rejuvenation profile, including decreased expression of aging-related genes and a transcriptomic signature of younger retina. Finally, we present the first human genetic data showing significant association of several variants in the human locus with the onset of intermediate AMD, underlying the translational significance of our findings. In sum, our study identifies novel therapeutic opportunities and defines ELOVL2 as a promising target for interventions aimed at preventing age-related vision loss.
视网膜富含多不饱和脂肪酸(PUFAs),这些脂肪酸主要定位于细胞膜,在细胞膜中它们决定着膜的生物物理特性,如扩散、通透性、结构域形成和曲率产生。在衰老过程中,脂质代谢的改变导致视网膜中极长链多不饱和脂肪酸(VLC-PUFAs)含量降低,这种下降与正常的年龄相关性视力下降以及病理性年龄相关性黄斑变性(AMD)有关。(极长链脂肪酸延伸样蛋白2)编码一种跨膜蛋白,该蛋白可产生二十二碳六烯酸(DHA)和VLC-PUFAs的前体,其启动子的甲基化水平目前是实际年龄的最佳预测指标。在此,我们表明缺乏ELOVL2特异性酶活性的小鼠在强光照射后对比敏感度受损,视杆细胞反应恢复较慢。在老年动物玻璃体内补充ELOVL2的直接产物24:5n-3可显著改善视觉功能,并减少视网膜色素上皮(RPE)下沉积物中载脂蛋白E、HTRA1和补体蛋白的积累。在分子水平上,在补充24:5n-3的视网膜中观察到的基因表达模式呈现出部分年轻化特征,包括衰老相关基因表达降低以及年轻视网膜的转录组特征。最后,我们展示了首批人类遗传数据,表明人类基因座中的几个变体与中度AMD的发病显著相关,这突出了我们研究结果的转化意义。总之,我们的研究确定了新的治疗机会,并将ELOVL2定义为旨在预防年龄相关性视力丧失的干预措施的一个有前景的靶点。