Department of Biological and Agricultural Engineering, Louisiana State University, Baton Rouge, LA, 70803, USA.
Veterinary Clinical Sciences, Louisiana State University and LSU Veterinary Medicine, Skip Bertman Drive, Baton Rouge, LA, 70803, USA.
Sci Rep. 2021 Jun 10;11(1):12270. doi: 10.1038/s41598-021-90792-5.
Polymeric nanoparticles have been investigated as potential delivery systems for therapeutic compounds to address many ailments including eye disease. The stability and spatiotemporal distribution of polymeric nanoparticles in the eye are important regarding the practical applicability and efficacy of the delivery system in treating eye disease. We selected poly(lactic-co-glycolic acid) (PLGA) nanoparticles loaded with lutein, a carotenoid antioxidant associated with eye health, as our model ophthalmic nanodelivery system and evaluated its stability when suspended in various conditions involving temperature and light exposure. We also assessed the ocular biodistribution of the fluorescently labeled nanoparticle vehicle when administered topically. Lutein-loaded nanoparticles were stable in suspension when stored at 4 °C with only 26% lutein release and no significant lutein decay or changes in nanoparticle morphology. When stored at 25 °C and 37 °C, these NPs showed signs of bulk degradation, had significant lutein decay compared to 4 °C, and released over 40% lutein after 5 weeks in suspension. Lutein-loaded nanoparticles were also more resistant to photodegradation compared to free lutein when exposed to ultraviolet (UV) light, decaying approximately 5 times slower. When applied topically in vivo, Cy5-labled nanoparticles showed high uptake in exterior eye tissues including the cornea, episcleral tissue, and sclera. The choroid was the only inner eye tissue that was significantly higher than the control group. Decreased fluorescence in all exterior eye tissues and the choroid at 1 h compared to 30 min indicated rapid elimination of nanoparticles from the eye.
聚合物纳米粒已被研究作为治疗化合物的潜在传递系统，以解决包括眼部疾病在内的许多疾病。聚合物纳米粒在眼部的稳定性和时空分布对于传递系统在治疗眼部疾病中的实际应用和疗效非常重要。我们选择负载叶黄素的聚（乳酸-共-乙醇酸）（PLGA）纳米粒作为我们的模型眼部纳米传递系统，并评估了其在不同温度和光照条件下悬浮时的稳定性。我们还评估了荧光标记的纳米粒载体经局部给药后的眼部生物分布。叶黄素负载的纳米粒在 4°C 下储存时在悬浮液中稳定，只有 26%的叶黄素释放，没有明显的叶黄素降解或纳米粒形态变化。在 25°C 和 37°C 下储存时，这些 NPs 显示出大量降解的迹象，与 4°C 相比，叶黄素降解明显，在悬浮液中 5 周后释放超过 40%的叶黄素。与游离叶黄素相比，叶黄素负载的纳米粒在暴露于紫外（UV）光时也更能抵抗光降解，降解速度约慢 5 倍。当体内局部应用时，Cy5 标记的纳米粒在外眼部组织（包括角膜、巩膜组织和巩膜）中表现出高摄取。脉络膜是唯一比对照组明显高的内眼组织。与 30 分钟相比，所有外眼部组织和脉络膜在 1 小时时的荧光强度降低表明纳米粒从眼部迅速消除。
