Harmane

A β-carboline with diverse biological activities; an inhibitor of MAO-A (IC50 = 0.5 µM) that also inhibits MAO-B (IC50 = 5 µM); an inverse agonist of GABAA receptors (IC50s = 7.2 and 8.3 µM in radioligand binding assays using rat brain and bovine retina, respectively); a DNA intercalating agent that induces cell cycle arrest at the G1 phase in NCI-H460 cells and the G2 phase in T47D and HCT116 cells and induces apoptosis in HCT116 cells at 50 µM; has mutagenic and carcinogenic effects and induces the transcription of the AhR target CYP1A1 in HepG2 cells at 1-50 µM; prevents memory retrieval deficits induced by 24, but not 12 or 36, hours of REM sleep deprivation in mice in contextual and fear conditioning paradigms at 2.5 mg/kg; inhibits memory consolidation when administered following training at doses of 5 and 10 mg/kg in one-trial passive-avoidance task; selectively neurotoxic to dopaminergic neurons in C. elegans; plasma levels are increased in patients with essential tremor and Parkinson’s disease