阿茲海默症是神經退化性疾病的一種主要疾病，其主要的病理特徵是神經細胞內纖維化糾結以及腦細胞外老年斑塊，而貝它類澱粉蛋白的聚集則是造成老年斑塊的主要原因。儘管貝它類澱粉蛋白已經受到廣泛的研究，但目前其沉積聚集的機制還尚未清楚。本次實驗在探討脯胺酸及脯胺酸衍生物所組成的短胜肽鏈對於貝它類澱粉蛋白的影響。
本研究中，我們選擇貝它類澱粉蛋白中最重要的一段胺基酸序列 14-25 ( HQKLVFFAEDVG ) 來做研究，合成一系列接上聚脯胺酸或聚脯胺酸衍生物之胜肽鏈共五段 : 未接上脯胺酸 (WT-Aβ (14-25))，在碳端的位置接上六個脯胺酸 (Aβ (14-25)-(Pro)6)、順式羥脯胺酸 (Aβ (14-25)-(hyp)6) 以及反式羥脯胺酸 (Aβ (14-25)-(Hyp)6)，另外製備一胜肽，在氮端和碳端的位置上各接上六個反式羥脯胺酸 ((Hyp)6-Aβ (14-25)-(Hyp)6)。利用螢光光譜儀、穿透式電子顯微鏡以及圓二色光譜儀來探討這些胜肽鏈是否對 Aβ 沉積具有抑制的效果。最後在將這些胜肽鏈與 WT-Aβ (14-25) 混合，然後觀察其抑制類澱粉沉澱之情形。
經由螢光光譜和 TEM 的測量，我們可以知道在 Aβ (14-25) 的碳端位置接上六個脯胺酸以及羥脯胺酸都可以抑制類澱粉纖維的產生，而且羥脯胺酸抑制效果比脯胺酸還要好。然而當這些接有聚脯胺酸或聚脯胺酸衍生物的 Aβ 胜肽與原生 Aβ 胜肽混合後，並無抑制的效果。

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