Hypericum perforatum L. - syn. Hypericum vulgare Lam. - Hypericaceae
perforate St.John's wort, klamath weed, (Tüpfel-) Johanniskraut, Tüpfel-Hartheu
Perennial herb, up to 1m tall, native to Europe, West Asia; stems erect from creeping and rooting base; leaves narrowly elliptic to narrowly oblong or linear, yellowish-green with abundant translucent dots, main lateral veins 2-paired; inflorescence 3- to numerous-flowered, flowers stellate, petals golden yellow, black glands few on sepals and petals.
The dried flowering tops (Hyperici herba) are used as antidepressant and for wound healing. „Used for healing since ancient times but today mainly for treating mild depression, mood disturbances, anxiety and nervous conditions. It is popular to treat wounds and burns, inflammations of stomach and intestines, against internal worms… Both hypericin and hyperforin are apparently responsible for a calming and mild antidepressant effect…“
[Medicinal Plants of the World. Ben-Erik Van Wyk and Michael Wink, Pretoria 2004, 175]
The EtOAc extract of H.perforatum contained flavonoids (rutin, hyperoside, isoquercitrin, quercitrin, quercetin and biapigenin, 1.75%), hypericins (hypericin and pseudohypericin; 0.13%) and hyperforins (hyperforin and adhyperforin; 0.77%).
[Extracts from St John's wort and their antimicrobial activity., Avato, P., Raffo, F., Guglielmi, G., Vitali, C., Rosato, A., Phytotherapy research, 18(3), 2004, 230-232]
Hyperforin-induced nonselective cation influx is blocked by TRP channel blockers in PC12 cells.
[Hyperforin-a key constituent of St. John’s wort specifically activates TRPC6 channels., Leuner, K., Kazanski, V., Müller, M., Essin, K., Henke, B., Gollasch, M., Müller, W.E., The FASEB Journal, 21(14), 2007, 4101-4111] http://www.fasebj.org/content/21/14/4101.long
„Hyperforin is believed to be the primary active constituent responsible for the antidepressant and anxiolytic properties of the extracts of St. John's wort. It acts as a reuptake inhibitor of monoamines, including serotonin, norepinephrine, dopamine, and of GABA and glutamate, with IC50 values of 0.05-0.10 mcg/ml for all compounds, with the exception of glutamate, which is in the 0.5 mcg/ml range. It appears to exert these effects by activating the transient receptor potential ion channel TRPC6. Activation of TRPC6 induces the entry of sodium and calcium into the cell which causes inhibition of monoamine reuptake. Hyperforin is also thought to be responsible for the induction of the cytochrome P450 enzymes CYP3A4 and CYP2C9 by binding to and activating the pregnane X receptor (PXR).“
[„Hyperforin“. PubChem Compound. National Center for Biotechnology Information. Retrieved 7 July 2015.] http://www.drugbank.ca/drugs/DB01892
Lindman,C.A.M., Bilder ur Nordens Flora, vol.2 t.230 (1922-1926)
flowering Hypericum perforatum, author: Andreas Kraska, CC BY-SA 3.0