2012-08-012024-05-18https://scholars.lib.ntu.edu.tw/handle/123456789/705373摘要：犬漸進性視網膜萎縮症(PRA)為臨床獸醫眼科門診最常見的一類因視網膜病變導致失明的疾病。此視網膜病變導致患犬視力下降至完全失明，然而此病至今仍無有效的治療或延緩惡化的方法。在我們之前中草藥於大鼠眼睛疾病的前導實驗中，初步結果發現枸杞萃出物在糖尿病及青光眼大鼠具有延緩抑制視網膜病變的效果，於是在本研究中我們很有興趣進一步了解並比較兩類抗氧化草藥（葡萄籽原花青素與枸杞）萃出物，對於大鼠誘導之視網膜退化以及患有視網膜萎縮症之臨床犬隻病患，在視網膜的保護效力及抗氧化之效力。 本計劃包括多個實驗項目，預估將持續進行三年，第一年將建立光傷害誘導視網膜退化的大鼠模式，並分析視網膜病變大鼠之視網膜功能、視網膜組織病理、視網膜細胞凋亡、及視網膜中抗氧化/過氧化分子的濃度或活性，例如抗氧化物(GSH, GPx, SOD)、過氧化產物MDA等。自第二年起，視網膜病變大鼠分成八組，開始分組投予不同劑量與組合之抗氧化草藥（葡萄籽原花青素、枸杞）萃出物，並分析各餵食組大鼠之視網膜功能、視網膜組織病理、視網膜細胞凋亡等，此外，各餵食組大鼠氧化傷害之指標蛋白的濃度活性在視網膜及血液中均會分析比較。為評估抗氧化草藥萃出物對餵食動物整體健康的安全性，進行各餵食組大鼠血液學以及血液生化值之監測，並將重要器官如肝腎腦等進行病理組織分析，以了解不同劑量或種類之草藥萃出物對餵食動物是否有顯著的全身性副作用。依據第二年的實驗結果，將挑選出視網膜保護效力及抗氧化之效力最佳且安全之草藥萃出物之劑量與組合，進行下一年度犬隻臨床PRA病患之臨床試驗。計畫的第三年，為草藥萃出物之臨床試驗在眼科門診的犬PRA臨床病患，此為獸醫眼科界在此方面之首個臨床試驗。本研究為避免因為犬種差異及明顯遺傳基因之差異導致較多臨床試驗之變因，不易獲致營養補充對患犬視網膜保護效益之結論，故選擇在台灣視網膜退化症臨床發病率最高之長毛臘腸犬進行臨床試驗。參與試驗犬隻均接受詳細眼科檢查及該犬種PRA之缺陷基因RPGRIP1的DNA檢測。在病患飼主同意下，我們對草藥萃出物於臨床長毛臘腸犬PRA病患，將進行雙盲隨機、有安慰劑作對照組的臨床試驗，挑選自第二年實驗之草藥組中最有效且安全之草藥萃出物組合種類及劑量餵食長毛臘腸犬PRA病患。在臨床試驗前與臨床試驗期間，定期進行犬隻視網膜電波圖、眼底鏡檢查及神經反射評估，每次檢查的視網膜病變程度進行明確之分級及詳細記錄，以確定視網膜之病變程度及惡化速度。並分析血液中的抗氧化指標分子之濃度或活性，以了解抗氧化草藥萃出物對於臨床PRA犬隻之視網膜保護效力以及全身抗氧化效力。同時對於參加臨床試驗之PRA犬隻，進行血液學及血液生化值之監測，以了解草藥萃出物對於餵食犬隻是否具有臨床可見的全身性副作用。 本研究計畫之預期成果，有助於瞭解抗氧化草藥（葡萄籽原花青素與枸杞）萃出物，對於動物視網膜退化疾病的視網膜保護作用和抗氧化效力，並以科學方式分析此類草藥萃出物，是否未來可以成為臨床上犬PRA病患之視網膜病變延緩或輔助治療的好選擇之一，希望能帶給此無助之犬隻失明疾病之保健或輔助治療多一線希望。 <br> Abstract: Progressive retinal atrophies (PRA) are the most common blinding retinal degenerations in dogs seen in veterinary clinical practices. The vision of PRA affected dogs is gradually impaired and eventually leads to total blindness, but there is no effective treatment so far. In our pilot study on the effects of traditional Chinese herbs in rats with diabetic retinopathy in rats, wolfberry showed a protective role in retinal morphology and retinal electrophysiological function. Therefore, we are interested to understand further the neuroprotecitve and antioxidative effect of grape seed proanthocyanidins and wolfberry extract in an experimental induced retinal degeneration in rats and client-owned clinical canine PRA patients. The project is comprised of many sections for a period of 3 years. In the 1st yr, a light-induced retinopathy in rats will be established and characterized. Electroretinogram (ERG), retinal histolopathology, apoptosis, markers of oxidative stress in the retina of the disease model will be analyzed. In the 2nd year, grape seed proanthocyanidins and wolfberry extract will be fed to the rats with retinal degeneration. Electroretinogram (ERG), retinal histolopathology, apoptosis, markers of oxidative stress in the retina and plasma of rats of all feeding groups will be evaluated. The correlation of the status of oxidative stress between the retina and plasma will be analyzed. In the 3rd yr, a double-masked randomized placebo-controlled clinical trial of antioxidant herb extracts will be performed in clinical PRA patients of miniature longhaired dachshunds (MLHD), the top one leading PRA affected dog breed in Taiwan, to investigate the retinal protective effects in clinical MLHD patients following taking herb extracts. PRA in the MLHD is diagnosed and graded by ERG/fundoscopy and confirmed by DNA testing of mutant RPGRIP1gene. ERG, fundoscopy, pupillary light reflex, plasma levels of antioxidant markers, and CBC and biochemistry assays of the PRA-affected MLHD patients will be evaluated before the trial and every other month after starting the trial. The results of this 3-yr study will allow us to understand the retinal protective and antioxidative effects of grape seed proanthocyanidins and wolfberry extract in experimental retinal degeneration in rats and clinical canine PRA patients. The information obtained from this study could be useful in understanding the therapeutic or preventive potential of the herb extracts for the hopeless blinding disorder in dogs.葡萄籽原花青素枸杞萃出物抗氧化視網膜退化犬漸進性視網膜萎縮症犬grape seed proanthocyanidinswolfberryretinal degenerationprogressive retinal atrophyPRAdog