Hyperforin may be the main antidepressant constituent of St. John's
Recent research has suggested that hypericum extract, like synthetic
antidepressants, exerts its effect by dose-dependently inhibiting uptake
of the neurotransmitters serotonin, norepinephrine and dopamine. Determination
of the active constituent of hypericum has held researchers' interest
for some time. This study tested hyperforin, the major component of
the oily extract and a component of the hydroalcoholic extract as well.
Methanolic hypericum extract was shown to effectively and nonspecifically
inhibit uptake of the three neurotransmitters mentioned above, and hyperforin
likely is responsible for the observed result. Unlike any other anti-depressant
drug, hyperforin inhibits all three uptake systems similarly. Hypericin
and kaempferol, a flavonoid present in hypericum extract, failed to
show any such activity, leading to the conclusion that hyperforin is
the main anti-depressant compound. However, other mechanisms discussed
briefly in this paper may also play roles in this activity.
Müller W, Singer A, Wonnemann
M et al. Hyperforin represents the neurotransmitter reuptake
inhibiting constituent of hypericum extract. Pharmacopsychiat
1998; 31: 16-21.
© 2003 by Herb Research Foundation,
Boulder, CO, USA.