奈米/次微米與細碎枸杞對於光誘導視網膜退化大鼠模式的視網膜保護效力

Abstract

視網膜退化病變目前尚無有效的治療或預防方式，本研究將利用視網膜退化實驗動物模式，餵食具有明目功效的傳統中草藥枸杞，在大鼠模擬老年性黃斑部病變模式下進行研究，分析不同形式的枸杞是否具有預防視網膜退化和抗氧化延緩老化的效果。若於大鼠實驗獲致顯著正面效果，未來希望可以應用在臨床上的犬貓來預防或減緩視網膜退化。 將SD大鼠分為四組：Normal control組為正常飼養組；LI- model組為接受光誘導視網膜退化的無治療模式組；Milled組給予奈米/次微米介質研磨枸杞(250mg/kg)；Blended組給予細碎枸杞(250mg/kg)。兩個治療組每天餵食枸杞共54日，之間包括接受光傷害誘導視網膜退化到犧牲期間，都繼續餵食枸杞。在光誘導前一天以及誘導後第七天測量視網膜電波圖，並在犧牲後進行視網膜的病理和化學分析。 視網膜電波圖顯示，在光誘導視網膜退化後，餵食枸杞的兩組治療組a波與b波都有顯著保留視覺的功能，在兩治療組之間，介質研磨枸杞的a波保留程度表現比較好，可以保留約30%的波形。組織病理切片結果，兩治療組在視網膜外核層以及感光細胞層厚度都具有顯著的保留效果。視網膜中抗氧化物總麩胱甘肽的濃度以餵食介質研磨組顯著高於細碎枸杞治療組，過氧化物丙二醛的濃度則反之。 綜合結果顯示，枸杞在兩治療組中都對視網膜厚度以及能力具有保護的效果，奈米/次微米的研磨枸杞相較於一般細碎枸杞，在視網膜抗氧化物濃度有顯著的上升，對視網膜保護效果也顯著具有較佳的表現。

There is no effective treatment or prophylaxis way against retinal degeneration. Light-induced retinal degeneration in a rat model was used to assess the protective effect of traditional Chinese herb “Lycium barbarum” in the retina. The Lycium barbarum can be used for clinical treatment in dogs and cats with progressive retinal degeneration, if it shows a protective role in the retina. SD-rats were divided into four groups, namely Normal control, LI-model, Milled, and Blended. The Milled and the Blended groups were treated by feeding 250 mg/kg of Lycium barbarum once daily for 54 days including the period of light induction. The electroretinography (ERG) of all groups were assessed at the time of one day before and seven days after light induced retinal degeneration respectively. After the second ERG recording, both eyes were enucleated for histopathology and ELISA test. The ERG results showed that there was a decline in a- and b-wave in the Milled and the Blended groups. There was a better wave amplitude preservation in the Milled group. The visual function of the test rats in the Milled group was better than that in the Blended one. The retinal histopathology results presented significant protective effect in outer retina by thickness preservation. The GSH plus GSSG concentration was significantly higher and lower MDA level compared the Milled group with the Blended one. Briefly, the Milled and the Blended groups treated by Lycium barbarum showing protective effects in preservation of retinal thickness and function with elevated antioxidative capacity. The nano/submicron Lycium barbarum also showed better retinal protection and antioxidative effect than blended one.