Harmine, the main alkaloid in Ayahuasca, increased the pool of proliferating human neural progenitor cells by 71.5% after four days of treatment. Testing harmine analogs showed that a DYRK1A inhibitor (INDY) but not a monoamine oxidase inhibitor (pargyline) similarly boosted proliferation, suggesting harmine acts through DYRK1A inhibition. This mechanism may underlie both harmine's effects on neural cell growth and its reported antidepressant effects.
Harmine, a β-carboline alkaloid found in the psychotropic plant decoction Ayahuasca, increased the pool of proliferating human neural progenitor cells (hNPCs) by 57% after 4 days of treatment. The effect appears to be mediated through inhibition of the DYRK1A enzyme, as an analog that inhibits DYRK1A (INDY) similarly induced proliferation, while an inhibitor of monoamine oxidase (pargyline) did not. Harmine also increased dendritic arborization, including total neurite length, number of segments, extremities, and nodes in MAP2-positive neurons. These findings suggest a biological activity that may contribute to the antidepressant effects observed with Ayahuasca.