Department of Ophthalmology, University Hospital Schleswig-Holstein, Campus Lübeck, Lübeck, Germany.
Institute of Biomedical Optics, University of Lübeck, Lübeck, Germany.
Transl Vis Sci Technol. 2024 Jan 2;13(1):24. doi: 10.1167/tvst.13.1.24.
To investigate fluorescence lifetime of mouse models of age-related macular degeneration (AMD) by fluorescence lifetime imaging ophthalmoscopy (FLIO).
Two AMD mouse models, apolipoprotein E knockout (ApoE-/-) mice and NF-E2-related factor-2 knockout (Nrf2-/-) mice, and their wild-type mice underwent monthly ophthalmic examinations including FLIO from 3 months of age. After euthanasia at the age of 6 or 11 months, blood plasma was collected to determine total antioxidant capacity and eyes were enucleated for Oil red O (ORO) lipid staining of chorioretinal tissue.
In FLIO, the mean fluorescence lifetime (τm) of wild type shortened with age in both spectral channels. In short spectral channel, τm shortening was observed in both AMD models as well, but its rate was more pronounced in ApoE-/- mice and significantly different from the other strains as months of age progressed. In contrast, in long spectral channel, both model strains showed completely opposite trends, with τm becoming shorter in ApoE-/- and longer in Nrf2-/- mice than the others. Oil red O staining at Bruch's membrane was significantly stronger in ApoE-/- mice at 11 months than the other strains. Plasma total antioxidant capacity was highest in ApoE-/- mice at both 6 and 11 months.
The two AMD mouse models exhibited largely different fundus fluorescence lifetime, which might be related to the different systemic metabolic state. FLIO might be able to indicate different metabolic states of eyes at risk for AMD.
This animal study may provide new insights into the relationship between early AMD-associated metabolic changes and FLIO findings.
通过荧光寿命成像眼底镜（FLIO）研究年龄相关性黄斑变性（AMD）小鼠模型的荧光寿命。
从 3 月龄开始，对两种 AMD 小鼠模型（载脂蛋白 E 敲除（ApoE-/-）小鼠和 NF-E2 相关因子-2 敲除（Nrf2-/-）小鼠）及其野生型小鼠进行每月眼科检查，包括 FLIO。在 6 或 11 月龄安乐死后，采集血 plasma 以测定总抗氧化能力，并对眼球进行油红 O（ORO）脂质染色以检测脉络膜视网膜组织。
在 FLIO 中，野生型小鼠在两个光谱通道中的平均荧光寿命（τm）随年龄增长而缩短。在短光谱通道中，两种 AMD 模型也观察到 τm 缩短，但随着月龄的增长，ApoE-/-小鼠的缩短速率更快，且与其他品系有显著差异。相比之下，在长光谱通道中，两种模型品系表现出完全相反的趋势，ApoE-/-小鼠的 τm 比其他品系变短，而 Nrf2-/-小鼠的 τm 比其他品系变长。11 月龄时，ApoE-/-小鼠的 Bruch 膜内油红 O 染色明显强于其他品系。在 6 月龄和 11 月龄时，ApoE-/-小鼠的血浆总抗氧化能力最高。
两种 AMD 小鼠模型的眼底荧光寿命有很大差异，这可能与不同的全身代谢状态有关。FLIO 可能能够指示 AMD 高危眼的不同代谢状态。
杨晨
