摘要
目的 :研究抗氧化剂TA990 1抑制 β -淀粉样蛋白 (Aβ)聚集和纤维形成的机制。 方法 :运用傅里叶变换红外光谱法 (FT -IR)和曲线拟合法定量研究TA990 1对Aβ1-4 0 无细胞液体外老化过程中二级结构变化的影响。结果 :Aβ单独老化 30min ,β -折叠片含量为 43 17% ,β -转角为 32 9%。Aβ单独老化 7d ,β -折叠片增加约 10 % ,出现自由卷曲向 β -折叠转化。TA990 1与Aβ1-4 0 共同孵育 ,β -转角和 β -折叠片的含量分别为 2 3 5 %和2 6 4%。维生素E的存在主要减少了 β -折叠片的含量 (30 8% ) ,而二者联用使 β -转角的量 (16 7% )明显下降。结论 :TA990 1和VE均能抑制 β -折叠的形成 ,但以TA990 1对 β -转角和 β -折叠片的抑制作用较为强烈 ,提示其抑制Aβ的聚集和纤维形成的机制可能与抑制Aβ分子中 β -折叠结构的形成有关。
AIM: To investigate the mechanism that antioxidants TA9901, inhibit the formation of amyloid-β-protein(Aβ) fibril. METHODS: Fourier-transform infrared spectroscopy was used to study the secondary structure changes on aging Aβ in vitro. RESULTS: Aβ aged alone for 30 min, the content of β-pleated sheet and β-turn were 43.17% and 32.9% respectively. Aβ aged alone for 7 days, the content of β-pleated sheet increased abuot 10% and produced a shift of random coil toward β-pleated sheet. TA9901 induced a significant decrease of the content of β-turn (23.5%) and β-pleated sheet (26.4%). VE mainly decreased the β-pleated sheet content (30.8%). The combination of TA9901 and VE promoted transition of β-turn (16.7%) toward α-helix and random coil. CONCLUSIONS: Both of TA9901 and VE can effectively diminish the β-structural content. TA9901 showed more intensitive inhibition than VE. The effect of TA9901 on the secondary structure of aged Aβ was associated with the mechanism that TA9901 inhibited Aβ aggregation and fibril formation.
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2000年第6期540-544,共5页
Chinese Journal of Pathophysiology
关键词
淀粉样Β-蛋白
抗氧化药
早老性痴呆
FT-
IR
Alzheimer's disease
Amyloid beta-protein
Antioxidants
Spectra
Fourier transform infrared
