Extracts of Hypericum perforatum (St. John’s Wort) are widely used for the treatment of depressive disorders and are unspecific inhibitors of the neuronal uptake of several neurotransmitters. Previous studies have shown that hyperforin represents the reuptake inhibiting constituent. To characterize the mechanism of serotonin reuptake inhibition, kinetic analyses in synaptosomes of mouse brain w...

Hyperforin is a constituent of St. John's wort and coexists with the singlet oxygen sensitizer hypericin. Density functional theory, molecular mechanics and Connolly surface calculations show that accessibility in the singlet oxygen "ene" reaction favors the hyperforin "southwest" and "southeast" prenyl (2-methyl-2-butenyl) groups over the northern prenyl groups. While the southern part of hype...

background & aim: st john's wort (hypericum perforatum l.) contains hypericin and hyperforin as the main components of the extract that binds with gaba and sigma opioid receptors. this herb has many pharmacological effects, including analgesic, sedative, soothing, antispasmodic, anticonvulsant, anti-depressant, and anti-bacteria. in this study examined the effect of two concentrations of hy...

St. John's wort has been used to treat a variety of conditions. Several brands are standardized for content of hypericin and hyperforin, which are among the most researched active components of St. John's wort. St. John's wort has been found to be superior to placebo and equivalent to standard antidepressants for the treatment of mild to moderate depression. Studies of St. John's wort for the t...

Extracts of Hypericum perforatum (St. John’s Wort) are widely used for the treatment of depressive disorders and are unspecific inhibitors of the neuronal uptake of several neurotransmitters. Previous studies have shown that hyperforin represents the reuptake inhibiting constituent. To characterize the mechanism of serotonin reuptake inhibition, kinetic analyses in synaptosomes of mouse brain w...

Background & Aim: St John's wort (Hypericum perforatum L.) contains hypericin and hyperforin as the main components of the extract that binds with GABA and sigma opioid receptors. This herb has many pharmacological effects, including analgesic, sedative, soothing, antispasmodic, anticonvulsant, anti-depressant, and anti-bacteria. In this study examined the effect of two concentrations of Hyperi...

Continuous use of St. John's wort decreases the bioavailabilities of a variety of drugs. This interaction is attributed to the induction of cytochrome P450 3A4 and/or P-glycoprotein. In this study, we aimed to examine the chronic effects of St. John's wort and its constituents, hyperforin and hypericin, on the expression and function of P-glycoprotein in an intestinal cell line, LS 180. We also...

Therapeutic uses of Hypericum extracts have been demonstrated as safe and effective in treating mild to moderate depression in numerous clinical trials. To date, however, no definitive statements on their mode of action can be made, and little information on their electrophysiological effects is available. The present communication summarises the results of our efforts directed towards clarifyi...

The study shows the influence of the origin of plant material and biological source on the in vitro antioxidant (neutralization of DPPH and OH radical, nitric oxide, and inhibition of lipid peroxidation) and anticholinesterase activity of chemically characterized and quantified ethanol extracts of ten St. John's wort samples. The investigated samples were: five Hypericum perforatum species repr...

Hypericum perforatum (St John's wort) is a well known medicinal plant used in many pharmaceutical formulations and its main active compound is hypericin. The purpose of our study was to examine the plasma level of hypericin upon long term mice treatment with Hyperici herba extract. A reversible hyperthermia was recorded upon 2 hours of the extract administration, both in males and females. Hype...