Neurite Outgrowth-Promoting Activity of Compounds in PC12 Cells from Sunflower Seeds.

ABSTRACT: In the current super-aging society, the establishment of methods for prevention and treatment of Alzheimer's disease (AD) is an urgent task. One of the causes of AD is thought to be a decrease in the revel of nerve growth factor (NGF) in the brain. Compounds showing NGF-mimicking activity and NGF-enhancing activity have been examined as possible agents for improving symptoms. In the present study, sunflower seed extract was found to have neurite outgrowth-promoting activity, which is an NGF-enhancing activity, in PC12 cells. To investigate neurite outgrowth-promoting compounds from sunflower seed extract, bioassay-guided purification was carried out. The purified active fraction was obtained by liquid-liquid partition followed by some column chromatographies. Proton nuclear magnetic resonance and gas chromatography-mass spectrometry analyses of the purified active fraction indicated that the fraction was a mixture of ?-sitosterol, stigmasterol and campesterol, with ?-sitosterol being the main component. Neurite outgrowth-promoting activities of ?-sitosterol, stigmasterol, campesterol and cholesterol were evaluated in PC12 cells. ?-Sitosterol and stigmasterol showed the strongest activity of the four sterol compounds (?-sitosterol ? stigmasterol > campesterol > cholesterol), and cholesterol did not show any activity. The results indicated that ?-sitosterol was the major component responsible for the neurite outgrowth-promoting activity of sunflower seeds. Results of immunostaining also showed that promotion by ?-sitosterol of neurite formation induced by NGF was accompanied by neurofilament expression. ?-Sitosterol, which showed NGF-enhancing activity, might be a candidate ingredient in food for prevention of AD.

SUBMITTER: Koga T 

PROVIDER: S-EPMC7587564 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature