Neurite outgrowth promoting activity of marine algae from Japan against rat adrenal medulla pheochromocytoma cell line, PC12D.

We screened for biological activity which induces neurite outgrowth in vitro from 300 species of marine algae from along the Japan coast for possible use as a treatment for the lack of neurotrophic factor which is considered to be a cause of Alzheimer's disease. In this study, we evaluated the neurite outgrowth promoting activity in a rat adrenal medulla pheochromocytoma cell line, PC12D, using a low level of NGF (nerve growth factor). Although most of the samples had no activity, MeOH extract from a brown alga, Sargassum macrocarpum and PBS extract from a red alga, Jania adharens, exhibited neurite outgrowth promoting activity and induced neuron specific dendrites and axons from the surfaces of PC12D cells. The active substance present in S. macrocarpumseemed to be lipid and heat stable with molecular weight of around 500 to 1000. These results suggest that marine algae may constitute a good source for development of promising novel agents with neurotrophic activity in brain nerve systems for future use in treatment of Alzheimer's disease.