The harmala alkaloid,
harmine (
1) is found in various plants such as the
Passiflora species and has monoamine oxidase inhibition, psychotropic activity and so on. Onishi
et al. have established an assay system using mouse cells expressing the
Bmal1 promoter-driven luciferase reporter gene, which is one of the clock genes related to circadian rhythm. After administering
1 to the mouse cells, the circadian period was extended. This result suggested that it was caused by the
Bmal1 promoter transactivation and the increase of
Bmal1 transcriptional factor.