Valerenic acid

Valerenic acid is a sesquiterpenoid constituent of the essential oil of the Valerian plant. Not to be confused with valeric acid.

Valerian is used as a herbal sedative which may be helpful in the treatment of insomnia. While the precise mechanism of this action has not been established and it is likely that several different components of the plant contribute to the effect, valerenic acid is thought to be at least partly responsible for the sedative effects.

Valerenic acid has been demonstrated to be both a subtype-selective GABAA agonist acting mainly at α1β2 and α1β3 subtypes, and also a 5HT5A partial agonist. Both of these actions are likely to play a role in the sedative effects of this compound, as other GABAA agonists such as benzodiazepines are commonly used as sedative drugs, and while no selective 5HT5A agonists are currently used medically, the 5HT5A receptor is known to be highly expressed in the suprachiasmatic nucleus of the brain, which is believed to be involved in the sleep-wake cycle.

Valerenic acid has also been reported to be an NF-κB inhibitor, and may be partly responsible for the reported anti-inflammatory action of the valerian plant.