Methysticin is one of the six major kavalactones found in the kava plant.
[1] Research suggests that methysticin and the related compound dihydromethysticin have CYP1A1 inducing effects which may be responsible for their toxicity.
[2] Additionally, methysticin has been shown to potentiate GABAA receptor activity, contributing to the overall anxiolytic profile of the kava plant.
This enzyme is involved in the toxification of benzo[a]pyrene into (+)-benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide, a highly carcinogenic substance.
[2][4][5] No report so far has described enhancement of CYP1A1 expression in animals or humans in vivo from any constituent of kava.