Amyloid ${eta}-peptide$에 의해 유도되는 세포사멸을 보호하는 물질을 검색하기 위하여 250여 식물 재료 및 식품성분으로부터 스크리닝한 결과 가장 효과가 있는 시금치 추출물을 이용하여 뇌신경세포사멸(neuronal cell death)을 어느 정도 보호할 수 있는지를 알아보았다. 시금치 추출물이 항산화 활성과 acetylcholinesterase 활성에 대한 저해효과는 시금치 추출물 처리농도가 높을수록 유의적으로 높게 나타났다. 과산화수소와 amyloid ${eta}-peptide$에 의해 유도된 SH-SY5Y 세포주의 세포사멸에 대한 시금치추출액의 억제효과를 살펴본 결과, 과산화수소에 의한 세포사멸에 대하여 시금치 추출물은 억제효과를 나타내었으나, amyloid ${eta}-peptide$의 경우는 세포사멸억제효과를 나타내지 않았다.
To investigate the potential therapeutic value of a plant extract against amyloid ${eta}-peptide-induced$ cell damage, we first screened extracts of 250 herbs, and finally selected a water extract of Spinacia oleracea for further study. This extractshowed the potential to inhibit the reactions of oxidants. We measured the angiotensin-converting-enzyme (ACE) inhibitory activity of the extract, and assessed the ability of the extract to protect neuronal cells from chemical-induced cell death. SH-SY5Y neuroblastoma cells were used in this assay. The extract exerted protective effects on $H_2O_2-induced$ cell death, when $H_2O_2$ was used at 100 M, 200 M, and 500 M (protection of 87%, 73%, and 58%, respectively). When 50 M of amyloid ${eta}-peptide$ was added to the test cells, however, the extract had no protective effect on cell death. The extract inhibited ACE activity in a dose-dependent manner, and exhibited potent protection against the deleterious effects of $H_2O_2$. In sum, these results suggest that a water extract of Spinacia oleracea has the potential to afford protection against chemical-induced neuronal cell death, and the extract may be useful in the treatment of neurodegenerative diseases. The precise molecular mechanism of neuroprotection is under investigation.
