銀杏葉萃取物用於修復LED光源誘發小鼠視覺相關功能缺失與視網膜組織退化之效果

Ginkgo Biloba leaf extract recovers mouse vision-related functions and protects against retinal degeneration induced by LED light

蕭羽容(Yu-Rong Siao)

指導教授 ： 林培正 ； 陳伯易

中山醫學大學/醫學科技學院/生物醫學科學學系碩士班/碩士(2014年)

摘要

光誘發小鼠視網膜退化為常見的生物模式，用於探討與視覺退化相關的研究及預防策略。本研究探討銀杏葉萃取物 (Ginkgo Biloba Leaf Extract, Gk) 修復光誘發視覺相關功能缺失與視網膜組織退化的效果。對照組小鼠維持12小時光照 / 12小時黑暗之週期的飼育環境，光照強度採取60 lux的照度。實驗組小鼠採取12小時光照 / 12小時黑暗之週期的飼育環境，光照強度分別採取1000 lux或2600 lux的照度來誘發視網膜退化，光源使用LED燈泡 (簡稱E-Light)。組別分成：(1)不照光對照組 (Blank)、(2)光誘發視網膜退化組 (E-Light )、(3)光誘發視網膜退化後，不給予Gk治療組 (Post E-Light) 及 (4)光誘發視網膜退化後，給予Gk治療組 (Post E-Light / Gk)。結果發現，在2600 lux光刺激後，視覺相關功能受損，包含眼壓上升 (11.988 ±1.114 mmHg)、淚液分泌量減少 (1.856 ± 0.382 mm)、視覺敏感度降低 (0.067 ± 0.025 cpd)，以及在亮室的環境下，瞳孔面積會放大 (0.452 ± 0.348 mm2)。在組織層面也發現，視網膜ONL (Outer nuclear layer)、OS/IS (Outer segment / Inter segment)組織厚度變薄，及M-Cone cell、S-Cone cell細胞數量減少。給予服用100 mg/kg Gk後，能改善視覺相關功能的受損，使眼壓、淚液分泌量、視覺敏感度及瞳孔面積大小均恢復正常。也能修復視網膜組織的損傷，使視網膜ONL、OS/IS組織厚度增厚，及M-Cone cell、S-Cone cell細胞數量增加。本篇研究表明在小鼠模式中，銀杏葉萃取物可以修復光刺激所造成的小鼠視覺相關功能缺失及視網膜組織的退化。

關鍵字

銀杏葉萃取物 ； LED ； 感光細胞 ； 光誘發視網膜退化 ； 視覺相關功能

並列摘要

Light-induced retinal degeneration mice model is widely used to study mechanisms of retinal cell death and the prevention strategies. The goal in this study was to determine the efficacy of Ginkgo Biloba Leaf Extract (Gk) for recovery of visual function and retinal cellular structure in the well-established mouse model. Cyclic light exposure was set at 12 hr light / 12 hr dark per day in the blank control group. The experimental group were daily exposed to toxic bright LED light at 1000 lux and 2600 lux respectively (LED lamp referred as E-light) for 12 hr to induce photoreceptor degeneration and moved to darkness for 12 hr. This study includes four groups: (1) normal blank control group (referred as Blank); (2) light-induced retinal degeneration group (referred as E-Light); (3) light-induced retinal degeneration, without treatment with Gk (referred as Post E-Light); (4) light-induced retinal degeneration, with Gk treatment (referred as Post E-Light/Gk). After the LED light exposure, normal vision-related functions were damaged, such as rising intraocular pressure, decreasing tear production, decreasing visual acuity and enlarging pupil size. The ONL and OS/IS structures of the mouse retina were significantly damaged, and the density of cone cells was reduced as compared to that of the normal blank control group. After treatment with Gk, the intraocular pressure, tear production, visual acuity and pupil size were returned to normal, which was not found in the non Gk treatment group. Besides histological analysis revealed that the ONL and OS/IS layers, and the density of cone cells were rescued in the Gk treatment group as compared to the status in the non Gk treatment group. This study shows that Ginkgo Biloba Leaf Extract (Gk) has a role in recovery of vision-related functions and retinal cellular structures in the light- induced retinal degeneration model.

並列關鍵字

Ginkgo biloba leaf extract ； LED ； Photoreceptor ； Light-induced retinal degeneration ； Vision-related functions

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