原儿茶酸对M146L细胞APP mRNA表达的抑制作用

The Inhibition Effect of Protocatechuic Acid on the mRNA Expression of APP on M146L cell

目的:探讨原儿茶酸对M146L细胞APP mRNA表达的影响,寻找潜在的具有抑制Aβ分泌的中药单体,以达到治疗阿尔茨海默病(Alzheimer's disease,AD)的目的。方法:体外培养稳定转染人类阿尔茨海默病β淀粉样蛋白前体(amyloidβ-protein precursor,APP)基因及突变型早老素1(prsenilin-1,PS1)基因的CHO(Chinese hamsterovary cells)细胞系(M146L),使之高效产生β淀粉样蛋白42(amyloidβ-protein,Aβ42),建立Aβ42过度表达的细胞模型。加入待筛选的药物原儿茶酸,用MTT比色法检测不同浓度的原儿茶酸(0.25、0.5、1.0、2.0 mmol/L)对M146L细胞的毒性作用,应用RT-PCR法检测原儿茶酸对M146L细胞APP mRNA表达的影响。结果:浓度0.25、0.5、1.0mmol/L的原儿茶酸对M146L细胞存活率无明显影响,不具有细胞毒性作用,对M146L细胞APP mRNA表达有抑制作用,并呈剂量依赖性。结论:一定剂量的原儿茶酸对M146L细胞APP mRNA表达有明显的抑制作用,其机制有待进一步研究。

Objective： To investigate the effect of protocatechuie acid on the mRNA expression of APP in double transfected （ hu- man APP gene and presenlin-1 gene） Chinese hamster ovary （CHO） cells （M146L）. Methods：A/342 overexpressing cell model was es- tablished in vitro by culturing Chinese hamster ovary cells stably expressing amyloid beta-protein precursor and mutant presenilin （M146L）. The MTr assay was used to test cytotoxicity of protocatechuic acid, and reverse transcription polymerase chain reaction （ RT- PCR） was carried out to determine the mRNA expression level of APP. Results ：The MTY assay showed that protocatechuie acid at suit- able concentrations didn＇t have cytotoxicity on M146L cell survival. Protocatechuic acid at the concentration of 0. 25 mmol/L,0. 5 mmol/L and 1.0 mmol/L significantly inhibited the mRNA expression of APP. Conclusion：The study suggests that the suitable dose of protocatechuic acid could inhibit the mRNA expression of APP in M146L cell, and its mechanism needs further study.