The present invention aims to provide a novel component involved in
angiogenesis, and a preventive and / or therapeutic agent for neurodegenerative diseases, demyelinating diseases, or cerebrovascular diseases using the same. [Solution] The
apelin expression
promoter of the present invention is an
apelin expression
promoter in vascular endothelial cells comprising one or more selected from the group consisting of mesenchymal stem cells, culture supernatant of mesenchymal stem cells, and cellular secretions of mesenchymal stem cells. The preventive and / or therapeutic agent of the present invention is a preventive and / or therapeutic agent for neurodegenerative diseases, demyelinating diseases, or cerebrovascular diseases comprising one or more selected from the group consisting of mesenchymal stem cells, culture supernatant of mesenchymal stem cells, and cellular secretions of mesenchymal stem cells.