早期研究證明姜黃中主要成分姜黃素可以改善患有類似阿爾茨海默氏癥（老年癡呆疾?。┠菢由窠?jīng)紊亂癥狀果蠅的活動(dòng)障礙，進(jìn)而延長果蠅壽命,。相關(guān)研究成果已發(fā)表在國際權(quán)威雜志PLoS One上,，在該研究中，研究人員發(fā)現(xiàn)姜黃素主要是在疾病的早期階段,，通過抑制對(duì)神經(jīng)元有毒性的纖維狀結(jié)構(gòu)以及淀粉樣纖維絲狀的碎片的形成發(fā)揮作用,。
從那以后，姜黃素一直被當(dāng)作能治療阿爾茨海默病的一種潛在藥物來研究,。阿爾茨海默氏癥的發(fā)病過程主要是粘性類淀粉樣物質(zhì)以及?；撬岬鞍桌w維的累積過程,。
近日，來自Linkoping大學(xué)的研究人員開展的一項(xiàng)研究探究了姜黃素是如何影響轉(zhuǎn)基因果蠅的阿爾茨海默氏癥樣的神經(jīng)紊亂癥,，以此希望能發(fā)現(xiàn)姜黃素發(fā)揮治療阿爾茨海默氏癥功效的確切靶點(diǎn),。
研究人員共設(shè)五組轉(zhuǎn)基因果蠅，這些果蠅都經(jīng)過基因缺失的方式操作而導(dǎo)致病變,。工作人員給予這些蒼蠅姜黃素后,，結(jié)果發(fā)現(xiàn)給予姜黃素的果蠅在壽命以及靈活性方面要明顯優(yōu)于那些未接受姜黃素治療的果蠅要高。
但奇怪的是,，研究者并沒有在果蠅大腦或是眼睛里觀察到淀粉樣物質(zhì)的減少,。這一現(xiàn)象表明姜黃素并不能溶解已形成的類淀粉樣斑塊。值得欣慰的是,，姜黃素能減少類淀粉樣斑塊形成的前體物質(zhì)的數(shù)量,，這一前體物質(zhì)形成減少后，低聚物樣的纖維物質(zhì)形成會(huì)大大減少,，而這些寡聚體是對(duì)大腦神經(jīng)細(xì)胞損害最大的一類有害物質(zhì),。
研究人員在果蠅動(dòng)物模型中觀察到的姜黃素減少大腦中類淀粉樣物質(zhì)的形成可能就是姜黃素發(fā)揮抗阿爾茨海默氏癥的作用機(jī)理。（生物谷Bioon.com）
doi:10.1371/journal.pone.0031424
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Curcumin Promotes A-beta Fibrillation and Reduces Neurotoxicity in Transgenic Drosophila
Ina Caesar1¤, Maria Jonson1, K. Peter R. Nilsson1, Stefan Thor2, Per Hammarstr?m1*
The pathology of Alzheimer's disease (AD) is characterized by the presence of extracellular deposits of misfolded and aggregated amyloid-β (Aβ) peptide and intraneuronal accumulation of tangles comprised of hyperphosphorylated Tau protein. For several years, the natural compound curcumin has been proposed to be a candidate for enhanced clearance of toxic Aβ amyloid. In this study we have studied the potency of feeding curcumin as a drug candidate to alleviate Aβ toxicity in transgenic Drosophila. The longevity as well as the locomotor activity of five different AD model genotypes, measured relative to a control line, showed up to 75% improved lifespan and activity for curcumin fed flies. In contrast to the majority of studies of curcumin effects on amyloid we did not observe any decrease in the amount of Aβ deposition following curcumin treatment. Conformation-dependent spectra from p-FTAA, a luminescent conjugated oligothiophene bound to Aβ deposits in different Drosophila genotypes over time, indicated accelerated pre-fibrillar to fibril conversion of Aβ1–42 in curcumin treated flies. This finding was supported by in vitro fibrillation assays of recombinant Aβ1–42. Our study shows that curcumin promotes amyloid fibril conversion by reducing the pre-fibrillar/oligomeric species of Aβ, resulting in a reduced neurotoxicity in Drosophila.
