摘要
目的研究姜黄素作用于阿尔采末病中APP淀粉样酶切途径的环节,探讨其抑制Aβ产生的作用机制。方法体外培养SHSY5Y细胞,以LipofectaminTM2000脂质体介导瞬时共转染pBACE1-mychis和pAPPswe两种质粒,姜黄素(0、1.25、5.0、20μmol.L-1)处理转染后的SHSY5Y细胞24h,以及5μmol.L-1姜黄素按时间梯度(0、12、24、48h)分别处理转染后的SHSY5Y细胞,通过RT-PCR检测APP和BACE1mRNA水平,Western blot检测BACE1和C99蛋白表达情况,ELISA检测Aβ40/42水平。结果经姜黄素处理后APP和BACE1mRNA表达水平都有明显减弱,呈浓度-时间依赖性(P<0.05);BACE1和C99蛋白表达也有不同程度的下调,呈浓度-时间依赖性(P<0.05);Aβ40/42表达水平明显降低,呈浓度-时间依赖性(P<0.05)。结论姜黄素能够抑制阿尔采末病相关基因APP mRNA表达;抑制APP的限速酶BACE1mRNA和蛋白表达;并抑制APP分解产物C99蛋白表达,都呈浓度-时间依赖性(P<0.05)。此外,姜黄素可以明显抑制APP的分解产物Aβ40/42的产生。
Aim To investigate the effects of Curcumin on the APP processing in the amyloidogenie pathway in vitro and explore its mechanisms on Aβ generation inhibition. Methods Plasmids APPswe and BACE1-mychis were transiently co-transfected in SH-SY5Y cell by Lipofectamin^TM 2000. The cell line then treated with Curcumin at 0, 1.25, 5, 20 umol·L^-1 for 24 h, or with Curcumin at 5 umol·L^-1 for0, 12, 24 and48 h for the time course assay. RT-PCR were performed to measure the endogenous levels of APP and BACE1 mRNA. Western blot were used to detect the protein expression of BACE1 and C99, the major β-secretase cleavage product. The concentration of AI540/42 was detected by β-amyloid 1 -40 or 42 Colorimetric ELISA. Results RT-PCR results showed that the mRNA levels of APP and BACE1 were decreased obviously in a dose-and time-dependent manner after treated with Cureumin in SH-SY5Y （P 〈 0. 05）. Western Blotting results showed that the expression of BACE1 and C99 protein were all decreased in a dose-and time-dependent manner （P 〈 0.05）. ELISA results showed that the generation of Aβ40/42 reduced significantly, also in a dose-and time-dependent manner （P 〈 0.05 ）. Conclusion Our finding demonstrated that Curcumin could inhibit the expression of the APP at mRNA; the expression of the BACE1 at mRNA and protein levels, furthermore it could inhibit the generation of Aβ40/42, and those changes were dose-time dependent （P 〈0. 05）. Those factors are key components in APP amyloidogenie pathway.
出处
《中国药理学通报》
CAS
CSCD
北大核心
2009年第3期361-366,共6页
Chinese Pharmacological Bulletin
基金
国家自然科学基金资助项目(No30600196)
重庆市自然科学基金资助项目(NoCSTC
2006BB5042)
2007年教育部留学回国人员科研启动基金(No教外司留[2007]1108号)
