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[effect of novoimanine on the cellular permeability indices of staphylococci].novoimanine is an antibacterial drug from hypericum perforatum l. when used in the bacteriostatic concentration, i.e. 0.5 gamma/ml, it induced release of potassium ions from the cells of staphylococcus aureus 209p and had no effect on release of the uv-absorbing compounds and 14c-amino acids. in addition, incubation of the cells with novoimanine (2.5--50 gamma/ml) provided "preservation" in them of the earlier absorbed 14c-amino acids, while in the control cells their level decreased. in a conce ...1977142441
[the modification of a radiation lesion in animals with an aqueous extract of hypericum perforatum l. 1].the preparation of hypericum perforatum l. has been shown to possess radioprotective properties. the effect found depends on the time of its taking and its concentration. a statistically reliable protection of marrow and the mucus of the thin intestine of mice from x-rays is observed.19921302510
[the modification of a radiation lesion in animals with an aqueous extract of hypericum perforatum l. 2].the preparation hypericum perforatum l. has been shown to decrease the intensity level of enzymatic and non-enzymatic processes of lipid peroxidation of rat liver microsomes in vitro and in vivo. in the mucus of the this intestine in vivo the increase of the number of non-enzymatic sh-groups is observed. possible mechanisms of radioprotective action of the preparation is under discussion.19921302514
vasoactive properties of procyanidins from hypericum perforatum l. in isolated porcine coronary arteries.procanidin fractions (pc) were isolated from hypericum perforatum l. (guttiferae). characterization of the main components of each fraction was performed by uv- and mass spectroscopy. their biological activity was tested in porcine isolated coronary arteries. all pc fractions antagonized histamine- or prostaglandin f2 alpha-induced arterial contractions. in contrast, vasorelaxation was insignificant in kcl-precontracted coronary arteries except with the higher oligomeric pc fraction 3. vasoactiv ...19911898419
[hypericum poisoning in sheep].a report about a case of st. john's wort poisoning in german blackface sheep is given. after the ingestion of st. john's wort (hypericum perforatum) all slightly pigmented parts of the skin, that were rarely covered with hair, were photosensitized. in summer many sheep suffered from inflammatory skin alterations at the ears, the bridge of the nose and at the surroundings of the eyes. a literature review informs about etiology and treatment of photosensitivity disease and the st. john's wort is e ...19892815063
[action of tannins from hypericum perforatum l. on the influenza virus]. 19724667029
[antibiotic preparations from hypericum perforatum l]. 19694981325
[antibiotic hyperforin from hypericum perforatum l]. 19715000144
consumption of poisonous plants (senecio jacobaea, symphytum officinale, pteridium aquilinum, hypericum perforatum) by rats: chronic toxicity, mineral metabolism, and hepatic drug-metabolizing enzymes.effect of dietary tancy ragwort (senecio jacobaea), comfrey (symphytum officinale), bracken (pteridium aquilinum) and alfalfa (medicago sativa) on hepatic drug-metabolizing enzymes in rats were measured. tansy ragwort and bracken increased (p less than 0.05) the activity of glutathione transferase and epoxide hydrolase. comfrey and alfalfa increased (p less than 0.05) the activity of aminopyrine n-demethylase. feeding bracken or st. john's wort (hypericum perforatum) in conjunction with tansy ra ...19827080084
[anti-inflammatory action of a group of plant extracts].use was made of wistar albino rats in which an inflammation was induced via the simultaneous injection of caraginan and prostaglandin e1 in order to evaluate the antiinflammatory activity of 6 freeze dried plant extracts. it was found that with such model of inflammation the inflammatory effect of caraginan was strongly enhanced, which was accompanied by the rapid and prolific white blood cell extravasates. the freeze-dried extracts of st. john's-wort (hypericum perforatum l.), potmarigold calen ...19817199215
[uterotonic action of extracts from a group of medicinal plants].water extracts (infusions) from a group of medicinal plants were studied in terms of their activity enhancing the uterine tonus in a series of experiments with a preparation of an isolated rabbit and guinea pig uterine horn. in a final extract concentration of 1 to 2 mg crude drug per 1 cm3 the plants ranked in the following descending order with regard to their tonus-raising effect on the uterus: camomile (matricaria chamomilla l.), potmarigold calendula (calendula officinalis l.) cockscomb (ce ...19817314446
an investigation of the type of photosensitization caused by the ingestion of st john's wort (hypericum perforatum) by calves. 19817343570
studies of sheep experimentally poisoned with hypericum perforatum.sheep given different dosages and frequencies of hypericum perforatum had decreased hemoglobin, red blood cell count, packed cell volumes, total protein, glucose, cholesterol, triglycerides, and serum alkaline phosphotase activities. blood urea nitrogen, sodium, potassium, bilrubin (total and direct), and the activities of aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase and gamma glutamyltransferase increased. hemato-biochemical assays were useful diagnostic aids to d ...19938236746
[phytoperfusion of the bladder after adenomectomy].for continuous irrigation of the bladder after prostatic adenomectomy herb infusion (urtica dioica l. 12-15 g/l, hypericum perforatum l. 8-12 g/l. marticaria recutita l. 8-10 g/l, folia plantaginis majoris 7-10 g/l, herba millefolii 4-6 g/l, folia betula 3-5 g/l. artemisia vulgaris l. 1-2 g/l, folia fragaria vesca 3-4 g/l, water 11 maximum) was dripped through a thin suprapubic and urethral drainages. such phytoperfusion of the urinary bladder used in 22 patients reduced postoperative blood loss ...19958571476
ncdeu update. natural product formulations available in europe for psychotropic indications.until the middle of this century, development of medical treatment for human disease was intimately connected with the plant kingdom. despite advances of the last three decades in utilizing chemical synthetic approaches to drug design and sophisticated structure-activity studies, there is still a great need for novel compounds with unique mechanisms of action in the field of medicine. while many thousands of structural analogs have been synthesized and tested, numerous gaps remain in the therape ...19958851648
inhibition of benzodiazepine binding in vitro by amentoflavone, a constituent of various species of hypericum.flower extracts of hypericum perforatum, hypericum hirsutum, hypericum patulum and hypericum olympicum efficiently inhibited binding of [3h]flumazenil to rat brain benzodiazepine binding sites of the gabaa-receptor in vitro with ic50 values of 6.83, 6.97, 13.2 and 6.14 micrograms/ml, respectively. single constituents of the extracts like hypericin, the flavones quercetin and luteolin, the glycosylated flavonoides rutin, hyperoside and quercitrin and the biflavone 13, ii8-biapigenin did not inhib ...19979204773
in vitro receptor binding and enzyme inhibition by hypericum perforatum extract.hypericum perforatum l. hypericaceae (st. john's wort), has been used since the time of ancient greece for its many medicinal properties. modern usage is still quite diverse and includes wound healing, kidney and lung ailments, insomnia and depression. this plant has been known to contain a red pigment, hypericin, and similar compounds, which have been assumed to be the primary active constituent(s) in this plant genus. a crude hypericum extract was tested in a battery of 39 in vitro receptor as ...19979342770
effects of long-term administration of hypericum extracts on the affinity and density of the central serotonergic 5-ht1 a and 5-ht2 a receptors.extracts of st. john's wort, hypericum perforatum l. (hypericaceae), are used as a phytotherapeutic antidepressant. a number of clinical studies demonstrate that their antidepressive potency is comparable to tricyclic antidepressants (tca). although the therapeutic effect of hypericum extracts is well documented, very little is known about the molecular mode of action. as the improvement of the depressive symptoms with both tca and hypericum extracts only occurs significantly after a lag phase o ...19979342771
[antioxidant properties of plant extracts].investigation of antioxidant properties of some plants was carried out. a group of plants exhibited antimicrobial activity was studied in detail. efficiency of plants as antioxidants was tested by the influence of their extracts on the yield of photochemiluminescence of gly-trp solutions. antioxidant properties were examined under conditions when their own absorption was minimized. riboflavin as additional sensitizer was used in this experiment for superoxide generation. the antioxidant effect w ...19989591094
solubilized hypericin and pseudohypericin from hypericum perforatum exert antidepressant activity in the forced swimming test.it has been shown recently that the fraction iiic of a crude extract of hypericum perforatum, (st. john's wort) that contained both hypericin (1) and pseudohypericin (2), was remarkably active in the rats forced swimming test (fst) after porsolt. however, neither of the naphthodianthrones isolated from this fraction were sufficiently effective when administered suspended in water. the solubility of 1 and 2 is remarkably increased in the presence of a fraction containing procyanidins, especially ...19989619107
antidepressant activity of hypericum perforatum and hyperforin: the neglected possibility.efforts leading to the identification of hyperforin as an antidepressive component of therapeutically used alcoholic hypericum extracts are described and discussed. initially, the effects of this unique and major constituent of the herb were detected in peripheral organs using in vitro models and an extract was obtained by supercritical extraction of the herb by carbon dioxide. these extracts are highly enriched in hyperforin (38.8%) and are devoid of hypericines and numerous other components of ...19989684942
effects of a methanolic extract and a hyperforin-enriched co2 extract of st. john's wort (hypericum perforatum) on intracerebral field potentials in the freely moving rat (tele-stereo-eeg).two extracts of st. john's wort (hypericum perforatum) were investigated in the animal model "tele-stereo-eeg" which consisted of continuous recording of intracerebral field potentials in the freely moving rat. one was a co2 extract for research purposes containing 30.14% hyperforin, a phloroglucine derivative known to occur within the reproductive parts of the plant, and lacking other major constituents like naphtodianthrones and flavonoids according to hplc fingerprint. the other extract was t ...19989684945
oral bioavailability of hyperforin from hypericum extracts in rats and human volunteers.validated analytical methods suitable for determining hyperforin in plasma after administration of alcoholic hypericum perforatum extracts containing hyperforin are described. after oral administration of 300 mg/kg hypericum extract (ws 5572, containing 5% hyperforin) to rats maximum plasma levels of approximately 370 ng/ml (approx. 690 nm) were reached after 3 h, as quantified by a hplc and uv detection method. estimated half-life and clearance values were 6 h and 70 ml/min/kg respectively. sin ...19989684946
hypericum perforatum inhibits the binding of mu- and kappa-opioid receptor expressed with the semliki forest virus system.the effects of hypericum perforatum extracts on in vitro [3h]naloxone binding to the human mu- and rat kappa-opioid receptors were studied in chinese hamster ovary (cho) cells using the semliki forest virus (sfv) expression system. binding of [3h]naloxone to the mu- and kappa-opioid receptor was inhibited in the presence of hypericum extracts showing ic50 values of approximately 25 and 90 micrograms/ml, respectively. in contrast, extracts of valeriana officinalis did not inhibit binding to the m ...19989708037
is st. john's wort (hypericum perforatum) an effective antidepressant?sjw is a remarkably safe antidepressant with an apparently unique mode of action. although it has demonstrated efficacy in mild and moderate depression when compared with placebo or tricyclic antidepressants, several research areas beg to be explored. its effects should be compared with serotonin reuptake inhibitors. studies in severely depressed patients are lacking, as are studies on its utility as a therapeutic adjunct to standard antidepressants.19989717868
hyperforin as a possible antidepressant component of hypericum extracts.we demonstrate that the phloroglucinol derivative hyperforin is not only the major lipophilic chemical constituent of the medicinal plant hypericum perforatum (st. john's wort) but also a potent uptake inhibitor of serotonin (5-ht), dopamine (da), noradrenaline (na), gaba and l-glutamate with ic50 values of about 0.05-0.10 microg/ml (5-ht, na, da, gaba) and about 0.5 microg/ml (l-glutamate) in synaptosomal preparations. furthermore, potencies of two different hypericum extracts in two convention ...19989718074
hypericum li 160 inhibits uptake of serotonin and norepinephrine in astrocytes.extracts of hypericum perforatum, commonly known as st. john's wort, are frequently used in germany and other european countries to treat mild to moderately severe depression, but the mechanism of antidepressant activity of hypericum is not understood. because known mechanisms of antidepressant activity include inhibition of serotonin and/or norepinephrine uptake, we investigated the effects of standardized extracts of hypericum li 160 on the transport of these monoamine neurotransmitters into a ...19999878826
extracts and constituents of hypericum perforatum inhibit the binding of various ligands to recombinant receptors expressed with the semliki forest virus system.extracts, fractions and constituents of hypericum perforatum were studied for in vitro receptor binding with various ligands to recombinant cns receptors expressed with the semliki forest virus expression system. for this purpose we have prepared membranes of cho cells with high density of several opioid, serotonin, estrogen, histamine, gabaa, neurokinin and metabotropic glutamate receptors, respectively. a lipophilic hypericum fraction revealed relatively potent inhibition to the binding of the ...199910071750
inhibition of human sperm motility by specific herbs used in alternative medicine.our purpose was to analyze sperm motility parameters in the presence of herbs.199910079411
screening of turkish anti-ulcerogenic folk remedies for anti-helicobacter pylori activity.the anti-helicobacter pylori effect of the extracts and fractions obtained from seven turkish plants, which are used in folk medicine for the treatment of gastric ailments including peptic ulcers, were studied against one standard strain and eight clinical isolates of h. pylori by using the agar dilution method. flowers of cistus laurifolius and spartium junceum, cones of cedrus libani, herbs and flowers of centaurea solstitialis ssp. solstitialis, fruits of momordica charantia, herbaceous parts ...199910473175
effect of dianthrones and their precursors from hypericum perforatum l. on lipoxygenase activity. 199910522277
effect of st. john's wort (hypericum perforatum) on cytochrome p-450 2d6 and 3a4 activity in healthy volunteers.the effects of the herb st. john's wort (hypericum perforatum), a purported antidepressant, on the activity of cytochrome p-450 (cyp) 2d6 and 3a4 was assessed in seven normal volunteers. probe substrates dextromethorphan (2d6 activity) and alprazolam (3a4 activity) were administered orally with and without the co-administration of st. john's wort. urinary concentrations of dextromethorphan and dextrorphan were quantified and dextromethorphan metabolic ratios (dmrs) determined. plasma samples wer ...200010698361
stimulation of the production of hypericins by mannan in hypericum perforatum shoot cultures.shoot organ cultures were established from callus derived from anthers of hypericum perforatum flowers and the effect of elicitors on hypericin and pseudohypericin production in shoot organ cultures was investigated. mannan stimulated pseudohypericin production up to four fold (0.82 mg/g dry wt) and hypericin production up to two fold (0.04 mg/g dry wt.) beta-1,3-glucan and pectin slightly stimulated pseudohypericin production (ca. two fold), but had no effect on hypericin production. on the oth ...200010703055
flavonoids from hypericum perforatum show antidepressant activity in the forced swimming test.it has been shown recently that a flavonoid fraction (fraction ii) obtained from a crude extract of hypericum perforatum (st. john's wort) was remarkably active in the forced swimming test (fst). fraction ii was further separated using mlccc to give fractions iia and iib. both fractions proved to be active in the fst at different dosages. further separation of fraction iia by preparative hplc yielded fraction iia1 which mainly was composed of hyperoside, isoquercitrin, miquelianin and quercitrin ...200010705724
a review of the benefits, adverse events, drug interactions, and safety of st. john's wort (hypericum perforatum): the implications with regard to the regulation of herbal medicines. 200010784267
topical application of st john's wort (hypericum perforatum l.) and of its metabolite hyperforin inhibits the allostimulatory capacity of epidermal cells.st john's wort (hypericum perforatum) is a traditional herbal medicine that is used for the topical treatment of superficial wounds, burns and dermatitis. the characteristic metabolites of st john's wort are the photodynamic active plant pigment hypericin and the phloroglucin-derivative hyperforin. to date, no studies on immunomodulatory properties of topical preparations of st john's wort have been performed. here, we investigated the alloantigen presenting function of human epidermal cells (ec ...200010809859
sunlight associated hyperthermia as a consistent and rapidly developing clinical sign in sheep intoxicated by st john's wort (hypericum perforatum).to assess the usefulness of rectal temperature responses in australian bred merino sheep, following the oral administration of hypericum perforatum (st john's wort), as an early indicator of hypericum intolerance.200010923184
potential use of medicinal plants in the treatment of alcoholism.the present paper briefly reviews the most relevant experimental data on the reducing effect of some medicinal herbs on voluntary alcohol intake in animal models of alcoholism. pueraria lobata, tabernanthe iboga, panax ginseng, salvia miltiorrhiza and hypericum perforatum proved to be effective in decreasing alcohol consumption. reduction of alcohol absorption from the gastrointestinal system appears to be a common feature among most of the above plants. these data suggest that medicinal plants ...200010930711
[interactions between herbal medicines and drugs].at present the use of medicaments of plant origin is on the increase. it is therefore necessary to take into consideration that there exist known as well as potential interactions between the medicament of the medicinal plant. the problematic plants include echinacea, allium cepa, gingko biloba, panax ginseng, as well as hypericum perforatum, valeriana officinalis, or glycyrrhiza glabra. its use should be limited, or completely excluded in the cases of simultaneous therapy with, e.g., warfarin, ...200010953464
effect of indian hypericum perforatum linn on animal models of cognitive dysfunction.the effect of a standardised 50% ethanolic extract of indian hypericum perforatum (ihp) was investigated for its putative nootropic activity on various experimental paradigms of learning and memory, viz. transfer latency (tl) on elevated plus-maze, passive avoidance (pa), active avoidance (aa), scopolamine and sodium nitrite induced amnesia (sia & nia) in albino rats. pilot studies indicated that single dose administration of ihp had little or no acute behavioural effects, hence the extract of i ...200010967462
inhibition of human cytochrome p450 enzymes by constituents of st. john's wort, an herbal preparation used in the treatment of depression.commercially available st. john's wort (hypericum perforatum) extracts, preparations that are used in the treatment of depression, were examined for the potential to inhibit human cytochrome p450 (cyp) enzyme activities, specifically cyp1a2, cyp2c9, cyp2c19, cyp2d6, and cyp3a4. crude extracts demonstrated inhibition of each of these five enzymes, with cyp2d6, cyp2c9, and cyp3a4 being more sensitive than cyp1a2 and cyp2c19. extracts were fractionated by hplc, and each of the fractions was tested ...200010871299
pharmacokinetics, safety, and antiviral effects of hypericin, a derivative of st. john's wort plant, in patients with chronic hepatitis c virus infection.hypericin is a natural derivative of the common st. johns wort plant, hypericum perforatum. it has in vitro activity against several viruses, including bovine diarrhea virus, a pestivirus with structural similarities to hepatitis c virus (hcv). we conducted a phase i dose escalation study to determine the safety and antiviral activity of hypericin in patients with chronic hcv infection. the first 12 patients received an 8-week course of 0.05 mg of hypericin per kg of body weight orally once a da ...200111158749
st john's wort induces intestinal p-glycoprotein/mdr1 and intestinal and hepatic cyp3a4.st john's wort (hypericum perforatum) is an herbal medicine that is frequently used for therapy of mild depression. recently, st john's wort was reported to substantially decrease blood/plasma concentrations and efficacy of cyclosporine (inn, ciclosporin), indinavir, and digoxin. in this study we investigated the mechanisms of these st john's wort-induced drug interactions.200011180019
antidepressant activity of indian hypericum perforatum linn in rodents.a standardised 50% aqueous ethanolic extract of indian hypericum perforatum (ihp) was investigated for its antidepressant activity on various experimental paradigms of depression, viz. behavioural despair (bd), learned helplessness (lh), tail suspension (ts) and reserpine-induced hypothermia (rih) tests in rats and mice. pilot studies indicated that single dose administration of ihp had very little or no acute behavioural effects, hence the ihp was administered orally at two dose levels (100 and ...199910865882
plasma pharmacokinetics and cerebrospinal fluid penetration of hypericin in nonhuman primates.hypericin, a polycyclic aromatic dianthroquinone, is a natural pigment derived from the plant hypericum perforatum (st john's wort). the compound has been synthesized and shown to inhibit the growth of malignant glioma cell lines in vitro via inhibition of protein kinase c. oral hypericin has entered clinical trials in adults with recurrent malignant glioma.200111221960
st. john's wort induces hepatic drug metabolism through activation of the pregnane x receptor.st. john's wort (hypericum perforatum) is an herbal remedy used widely for the treatment of depression. recent clinical studies demonstrate that hypericum extracts increase the metabolism of various drugs, including combined oral contraceptives, cyclosporin, and indinavir. in this report, we show that hyperforin, a constituent of st. john's wort with antidepressant activity, is a potent ligand (k(i) = 27 nm) for the pregnane x receptor, an orphan nuclear receptor that regulates expression of the ...200010852961
effects of hypericum perforatum extract on ethanol intake, and on behavioral despair: a search for the neurochemical systems involved.the present study investigated the possible involvement of sigma receptors and of serotonergic mechanisms in the effects of hypericum perforatum extract (hpe) on immobility time in the forced swimming test (fst) and on ethanol intake in marchigian sardinian alcohol-preferring rats. the hpe employed was a dry extract containing 0.3% hypericin and 3.8% hyperforin. intraperitoneal pretreatment with 20 mg/kg of the sigma receptor antagonist rimcazole (rim), 30 min prior to hpe, completely suppressed ...200010837849
adhyperforin as a contributor to the effect of hypericum perforatum l. in biochemical models of antidepressant activity.the present paper describe investigations which demonstrate that hyperforin is not the only phloroglucinol derivative in extracts of the medicinal plant hypericum perforatum l., which possess a biological activity. hyperforin was the major lipophilic constituent in two different extracts, whereas the amount of adhyperforin was approximately 10 times lower. adhyperforin, like hyperforin, is a potent inhibitor of the uptake of dopamine, serotonin and noradrenaline. neither hyperforin nor adhyperfo ...200111263672
evidence that total extract of hypericum perforatum affects exploratory behavior and exerts anxiolytic effects in rats.clinical trials have extensively reported the ability of hypericum perforatum extracts to exert a significant antidepressant activity. hypericin, the main constituent of h. perforatum extract, is no more regarded as the active principle of the antidepressant activity of the drug. hence, the question of which constituents are involved in the basic activity of the total extract, is still waiting for an answer. in the present study we focused our attention on the potential anxiolytic activity of h. ...200010764915
effect of the hypericum perforatum extract on serotonin turnover in the mouse brain.st. john's wort, a traditional herbal medicine obtained from the extract of hypericum perforatum, has been used in the treatment of mild depression. its mechanism of action remains to be established. the present study confirmed that hypericum extract exhibited very weak inhibitory activities towards mao. mouse brain mao activities was unchanged following either acute or chronic treatment with hypericum extract. 5-hiaa levels were found to be significantly increased in the cerebral cortex, hypoth ...200010761821
a1 adenosine receptors and their ligands: overview and recent developments.potent adenosine receptor (ar) agonists and antagonists with high selectivity for the a1ar subtype have been developed during the past decades. however, some of the compounds considered to be selective may not be as selective in humans as in rats, and may not be very selective versus the new ar subtypes a3 or a2b. partial agonists have been developed that may exhibit fewer side effects than full agonists. low water solubility of many a1 antagonists remains a problem. a1 ar antagonists can be cla ...200111347971
st john's wort (hypericum perforatum l.): a review of its chemistry, pharmacology and clinical properties.the chemical composition of st. john's wort has been well-studied. documented pharmacological activities, including antidepressant, antiviral, and antibacterial effects, provide supporting evidence for several of the traditional uses stated for st john's wort. many pharmacological activities appear to be attributable to hypericin and to the flavonoid constituents; hypericin is also reported to be responsible for the photosensitive reactions that have been documented for st. john's wort. with reg ...200111370698
effect of acute administration of hypericum perforatum-co2 extract on dopamine and serotonin release in the rat central nervous system.the hydromethanolic extract of hypericum perforatum has been shown to be an effective antidepressant, although its mechanism of action is still unclear. in this study, in vivo microdialysis was used to investigate the effects of hypericum perforatum-co2 extract on dopamine (da), 3,4-dihydroxyphenylacetic acid (dopac), serotonin (5-ht), and 5-hydroxyindoleacetic acid (5-hiaa) release in various areas of brain. administration of hypericum perforatum extract (1 mg/kg, p.o.) caused a slight, but sig ...200010721879
herb-drug interactions.concurrent use of herbs may mimic, magnify, or oppose the effect of drugs. plausible cases of herb-drug interactions include: bleeding when warfarin is combined with ginkgo (ginkgo biloba), garlic (allium sativum), dong quai (angelica sinensis), or danshen (salvia miltiorrhiza); mild serotonin syndrome in patients who mix st john's wort (hypericum perforatum) with serotonin-reuptake inhibitors; decreased bioavailability of digoxin, theophylline, cyclosporin, and phenprocoumon when these drugs ar ...200010675182
measurement of hyperforin a constituent of st. john's wort in plasma by high-performance liquid chromatography.hyperforin is a constituent of hypericum perforatum extracts (st. john's wort, h. perforatum), which have antidepressant action. hyperforin was extracted from plasma utilising a solid-phase extraction procedure. chromatography was performed by isocratic reversed-phase high-performance liquid chromatography with uv end-point detection. the calibration curve was linear over the range 0.15-3 microg per ml of plasma. the sensitivity for hyperforin was 4.5 ng on-column. mean inter- and intra-assay re ...199910670742
inhibition of interleukin-12 production in lipopolysaccharide-activated mouse macrophages by hpyericin, an active component of hypericum perforatum.hypericin, an active component of hypericum perforatum, was evaluated for the regulation of interleukin-12 (il-12) production in mouse macrophages. hypericin significantly inhibited il-12 production in lipopolysaccharide-activated macrophages in a dose-dependent manner (ic50 = 1.45 micrograms/ml). furthermore, hypericin potently inhibited the activation of il-12 gene promoter, suggesting that hypericin negatively regulated il-12 production at the transcription level. these results may explain so ...200111458458
role of alcoholic extract of shoot of hypericum perforatum linn on lipid peroxidation and various species of free radicals in rats.the alcoholic extract of the shoot of h. perforatum shows strong antioxidant property. it possesses the iron chelation property with more affinity to the ferrous form. it has scavenging property for both superoxide and for hydroxyl radicals but the response is more towards the superoxide radicals. thus in addition to the anti-depressant property it has strong antioxidant property also.199910641189
neurochemical studies on indian hypericum perforatum l.the effect of acute administration of 50% standardised ethanolic extract of indian hypericum perforatum (ihp) was studied on the rat brain concentrations of monoamines and their metabolites in five different brain regions, viz. hypothalamus, hippocampus, striatum, pons-medulla and frontal cortex by a hplc technique. ihp extract was administered at the doses of 50 and 200 mg/kg, p.o. and the brain monoamines were assayed after 30 min of the treatment. ihp treatment significantly decreased the lev ...200111491577
anti-inflammatory and analgesic activity of indian hypericum perforatum l.a standardised 50% aqueous ethanolic extract of the indian variety of hypericum perforatum (ihp) was examined for its putative anti-inflammatory and analgesic activity at the doses of 100 and 200 mg/kg, po. the experimental paradigms used were carrageenan induced pedal edema and cotton pellet induced granuloma for anti-inflammatory activity, whereas the tail flick, hot plate and acetic acid induced writhing methods were used to asses analgesic activity. indomethacin (20 mg/kg, ip) was used as th ...200111491578
anti-stress activity of indian hypericum perforatum l.indian hypericum perforatum (ihp) was investigated on a 14-day mild, unpredictable and inescapable foot shock stress (fss) induced perturbations in behaviour (depression), suppressed male sexual behaviour and cognitive dysfunction in albino rats. gastric ulceration, and adrenal gland and spleen weights, were also used as the stress indices. panax ginseng (pg) was used as the standard adaptogenic agent for comparison. fss induced marked gastric ulceration, significant increase in adrenal gland we ...200111491579
role of flavonoids in controlling the phototoxicity of hypericum perforatum extracts.hypericum perforatum extracts are used mainly as oral antidepressants. depending on source the extracts contain various amounts of phenylpropanes, flavonol derivates, biflavones, proathocyanidines, xanthones, phloroglucinoles, some amino acids, naphtodianthrones (hypericines) and essential oil constituents. the therapeutic use of hypericum perforatum extracts however is limited by their phototoxic potential. it was the aim of the present study to investigate the phototoxic potential of 3 hyperic ...200111515722
stimulation of glutamate, aspartate and gamma-aminobutyric acid release from synaptosomes by hyperforin.hyperforin is one pharmacologically active constituent of the medicinal herb hypericum perforatum. the mechanism of its antidepressant-like activity is currently considered to be the inhibition of synaptic reuptake of neurotransmitters. here, we will demonstrate that it also stimulates the release of glutamate from rat cortical synaptosomes, and that this effect is preceded by an increase in their free calcium [ca2+]i levels. these hyperforin-related effects were also observed in the absence of ...200111518057
a current review of the antimicrobial activity of hypericum perforatum l.a petrolether extract of the areal parts of hypericum perforatum l. was reported to be active against gram-positive bacteria. hyperforin, a phloroglucin derivative was shown to be the antimicrobial principle. hyperforin exhibited an excellent effect against methicillin-resistant strains of staphylococcus aureus with a mic value of 1.0 microg/ml. a butanol fraction of st. john's wort revealed anti-helicobacter pylori activity with mic values ranging between 15.6 and 31.2 microg/ml. recently, hydr ...200111518059
comparison of hypericum extracts with imipramine and fluoxetine in animal models of depression and alcoholism.clinical evidence suggests that hypericum extracts (hypericum perforatum l., st. john's wort) have antidepressive properties and may offer an interesting alternative for the treatment of mood disorders. in addition, hypericum extracts, as well as standard antidepressants such as the tricyclic, impramine, and the selective serotonin reuptake inhibitor, fluoxetine, have been reported to be of therapeutic benefit in the treatment of alcoholism, as these compounds may reduce alcohol craving and/or i ...199910625112
hyperforin attenuates various ionic conductance mechanisms in the isolated hippocampal neurons of rat.effects of hyperforin, an acylphloroglucinol derivative isolated from antidepressive medicinal herb hypericum perforatum (st. john's wort), on voltage- and ligand-gated ionic conductances were investigated. whole-cell patch clamp and concentration clamp techniques on acutely isolated hippocampal pyramidal neurons and on cerebellar purkinje neurons of rat were used. at concentrations between 3 to 100 microm hyperforin induced a dose and time dependent inward current which completely stabilized wi ...199910597894
neurochemical studies with st. john's wort in vitro.the effect of extracts and constituents of st. john's wort, hypericum perforatum, at various cns receptors were studied by radioligand binding techniques in order to determine a profile of pharmacological activity in vitro. binding inhibition was examined for the g-protein coupled opioid, serotonin (5-ht), histamine, neurokinin and corticotropin releasing factor (crf) receptors, for the steroid estrogen-alpha receptor and for the ligand-gated ionchannel gaba(a) receptor. hypericin showed the mos ...200111518063
hypericum perforatum l. extract does not inhibit 5-ht transporter in rat brain cortex.the hydroalcoholic extract of hypericum perforatum l. is an effective antidepressant, although its mechanism of action is still unknown. it inhibits the synaptosomal uptake of serotonin (5-ht), dopamine and noradrenaline, suggesting a biochemical mechanism similar to the synthetic standard antidepressants. in the present study, further investigating this hypothesis, we confirmed that a hydromethanolic extract of h. perforatum inhibited [3h]5-ht accumulation in rat brain cortical synaptosomes wit ...199910543427
pharmacological and endocrine effects of hypericum perforatum and hypericin after repeated treatment.clinical studies have demonstrated the antidepressant efficacy of hypericum (st. john's wort) extracts comparable to tricyclic antidepressants such as imipramine. we examined the effects of hypericum extract and hypericin, one active constituent, in the forced swimming test (fst) after treatment repeated for 14 days. it has recently been shown that hypericin was inactive in the fst after acute treatment, but remarkably active when solubilized by subfraction iiic1 containing mainly procyanidin b2 ...200111518068
effects of hyperforin on the fluidity of brain membranes.hyperforin, an acylphloroglucinol derivative isolated from hypericum perforatum (st. john's wort, sjw), affects several ionic conductance mechanisms in brain cells by an as yet unknown mechanism. we tested the effects of hyperforin on the fluidity of crude brain membranes from young guinea pigs. we performed fluidity measurements with three different fluorescent probes. diphenylhexatriene (dph) and trimethylammonium-diphenylhexatriene (tma-dph) anisotropy measurements were inversely correlated w ...200111518070
attenuation of alcohol intake by extract of hypericum perforatum (st. john's wort) in two different strains of alcohol-preferring rats.extract of the common plant hypericum perforatum l. (st john's wort, sjw) has been used successfully for the treatment of mild to moderate depression since ancient times and has recently been studied clinically. depression and alcoholism have some neurochemical similarities, such as low brain serotonin activities. thus, we hypothesized that sjw extract, which contains 0.22% hypericin and 4.05% hyperforin, also may be effective in suppressing alcohol intake. to test this hypothesis, the effects o ...199910528812
effects of hypericum perforatum extraction on alcohol intake in marchigian sardinian alcohol-preferring rats.the present study investigated the effect of acute intragastric (i.g.) administration of dry hypericum perforatum extract (hpe), containing 0.3% hypericin, on ethanol intake in genetically selected marchigian sardinian alcohol-preferring (msp) rats. the i.g. administration of hpe, 125 or 250 mg/kg, induced a 30-40% reduction in ethanol intake in rats offered 10% (v/v) ethanol for 2 h/day. the effect of these doses was selective, since they modified neither food intake nor food-associated drinkin ...199910528811
hypericin levels in human serum and interstitial skin blister fluid after oral single-dose and steady-state administration of hypericum perforatum extract (st. john's wort).the photodynamically active plant pigment hypericin, a characteristic metabolite of hypericum perforatum (st. john's wort), is widely used as an antidepressant. when administered orally, phototoxic symptoms may limit the therapeutic use of hypericin-containing drugs. here we describe the high-performance liquid chromatographic (hplc) detection of hypericin and semiquantitative detection of pseudohypericin in human serum and skin blister fluid after oral single-dose (1 x 6 tablets) or steady-stat ...199910461100
a double-blind randomised trial to investigate three different concentrations of a standardised fresh plant extract obtained from the shoot tips of hypericum perforatum l.the aim of this randomised double-blind multi-centre parallel group comparative study was to investigate the efficacy and tolerability of a new standardised fresh-plant extract obtained from the shoot tips of st. john's wort (hypericum perforatum l.) in the treatment of mild to moderate depression. 348 out-patients (259 female, 89 male) with mild to moderate depression were recruted by 12 psychiatrc specialty practices and 26 general practices. the patients took during 6 weeks 3 times a day 1 ta ...199910439477
modulation of ion channels in rat neurons by the constituents of hypericum perforatum.despite almost forty years of widespread use of antidepressant drugs, their mode of action is still unknown. hyperforin, a phloroglucinol derivative, is a major pharmacologically and therapeutically active constituent of hypericum perforatum extract that is widely used as an herbal antidepressant drug. however, the mechanism or mechanisms of action of these naturally abundant, non-toxic extracts remain unclear. enzymatically isolated patch-clamped rat central and peripheral neurons exposed to ra ...200111518081
effects of hypericum perforatum l. on evoked potentials in guinea pig hippocampal slices.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 clarifying the effects of an ethanolic hypericum extract (hyp) and its hydrosoluble fraction (hypws), and two o ...200111518083
efficacy of an hypericum perforatum (st. john's wort) extract in preventing and reverting a condition of escape deficit in rats.the treatment of unselected depressed patients with an hydro-alcoholic extract of hypericum perforatum has been reported to have an efficacy similar to that of classical antidepressants. in the present report, the effects of h. perforatum were studied on three animal models of depression: (i) an acute form of escape deficit (ed) induced by an unavoidable stress; (ii) a chronic model of ed, which can be maintained by the administration of mild stressors on alternate days; (iii) a model of anhedon ...199910432473
final report on the safety assessment of hypericum perforatum extract and hypericum perforatum oil.hypericum perforatum extract is an extract of the capsules, flowers, leaves, and stem heads of hypericum perforatum, commonly called st. john's wort. hypericum perforatum oil is the fixed oil from h. perforatum. techniques for preparing hypericum perforatum extract include crushing in stabilized olive oil, gentle maceration over a period of weeks, followed by dehydration and filtration. propylene glycol and butylene glycol extractions were also reported. the following components have variously b ...200111558639
hyperforin enhances the extracellular concentrations of catecholamines, serotonin and glutamate in the rat locus coeruleus.hyperforin is the main antidepressant component of hypericum perforatum (st. john's wort). using the push-pull superfusion technique we tested whether hyperforin influences extracellular concentrations of neurotransmitters in the rat locus coeruleus. hyperforin (10 mg/kg, i.p.) not only enhanced the extracellular levels of the monoamines dopamine, noradrenaline and serotonin, but also that of the excitatory amino acid glutamate. the levels of the main serotonin metabolite 5-hydroxyindolacetic ac ...199910218890
chemical and pharmacological evaluation of hypericum perforatum extracts.to determine the concentrations of chemical characteristic to extracts of leaves and flowers of hypericum perforatum (st john's wort) in a number of selected samples and, following chemical characterization, to investigate the effects of these extracts on several pharmacological properties including effects of the extracts on inhibition of 5-hydroxytryptamine (5-ht) uptake and on antioxidant properties.200011603291
the effects of st john's wort (hypericum perforatum) on human cytochrome p450 activity.st john's wort (hypericum perforatum) is a popular over-the-counter dietary supplement and herbal remedy that has been implicated in drug interactions with substrates of several cytochrome p450 (cyp) isozymes. the effect of st john's wort on cyp activity in vivo was examined with a probe drug cocktail.200111673747
intracellular localisation of hypericin in human glioblastoma and carcinoma cell lines.hypericin, a natural polycyclic quinone extracted from hypericum perforatum, has been recently shown to be a powerful sensitiser for photodynamic therapy (pdt). however, its intracellular localisation remains unclear and contradictory. in the present work we compared the intracellular localisation of hypericin in three cultured cell lines (adenocarcinoma cells widr, carcinoma cells nhik 3025 and glioblastoma cells d54mg) with the distribution of fluorescent probes specific to lysosomes (lysotrac ...200111702633
phototoxic effects of hypericum extract in cultures of human keratinocytes compared with those of psoralen.extracts of hypericum perforatum (st. john's wort) are used in the treatment of depression. they contain the plant pigment hypericin and hypericin derivates. these compounds have light-dependent activities. in order to estimate the potential risk of phototoxic skin damage during antidepressive therapy, we investigated the phototoxic activity of hypericin extract using cultures of human keratinocytes and compared it with the effect of the well-known phototoxic agent psoralen. the absorbance spect ...199910048312
red wine decreases cyclosporine bioavailability.many commonly ingested substances such as grapefruit juice and hypericum perforatum (st john's wort) have been found to interact with important therapeutic agents such as cyclosporine (inn, ciclosporin). the mechanism for these interactions is thought to involve modulation of the activity of the drug-metabolizing enzyme cytochrome p4503a4 (cyp3a4) and/or the drug transport protein pglycoprotein. in vitro data suggest that red wine may interact with cyp3a4 substrates such as cyclosporine.200111719733
st john's wort, a herbal antidepressant, activates the steroid x receptor.st john's wort (sjw), an extract of the medicinal plant hypericum perforatum, is widely used as a herbal antidepressant. recently, this agent has been found to adversely affect the metabolism of various coadministered drugs. steroid x receptor (sxr), an orphan nuclear receptor, induces hepatic cytochrome p450 gene expression in response to diverse endogenous steroids, xenobiotics and drugs. here, we report that, when coexpressed with sxr, a reporter construct derived from the cytochrome p450 3a ...200010974665
effects of acute and chronic treatment with hypericum perforatum l. (li 160) on different anxiety-related responses in rats.the study investigates the effects of acute and chronic oral treatment with hypericum perforatum l. (hp li 160, 62.5-500 mg/kg) in rats submitted to different anxiety models: the elevated t-maze (for inhibitory avoidance and escape measurements), the light/dark transition, and the cat odor test. these models were selected for their presumed capacity of evidencing specific subtypes of anxiety disorders as recognized in clinical practice. the results showed that acute hp (125 mg/kg) impaired eleva ...200211812530
an in vitro evaluation of human cytochrome p450 3a4 inhibition by selected commercial herbal extracts and tinctures.serial dilutions of 21 commercial ethanolic herbal extracts and tinctures, and 13 related pure plant compounds have been analyzed for their in vitro cytochrome p450 3a4 (cyp3a4) inhibitory capability via a fluorometric microtitre plate assay. roughly 75% of the commercial products and 50% of the pure compounds showed significant inhibition of cyp3a4 metabolite formation. for each herbal product and pure compound exhibiting dose-dependency, the inhibition values were used to generate median inhib ...200010969720
acute effects of li 160 (extract of hypericum perforatum, st john's wort) and two of its constituents on neuroendocrine responses in the rat.extracts of hypericum perforatum (st john's wort), such as li 160, which are effective antidepressants have several active constituents. their mode of action in depression, however, is unclear. in the present investigation, we assessed the effect of equivalent doses of li 160 and two of its components, hypericin and hyperforin on serotonin (5-ht) and dopamine (da)-mediated neuroendocrine responses in the rat. li 160, hypericin and hyperforin significantly and equivalently increased plasma cortic ...200011198053
the utilization of antidepressants in community-dwelling and institutionalized elderly--results form a representative survey in germany.given its widespread occurrence and consequences, old-age depression has to be regarded as a major public health problem. drug treatment has been proven effective in the majority of elderly individuals suffering from depression. this study presents pharmacoepidemiological data regarding the use of prescribed antidepressants and those purchased over the counter in the elderly. furthermore, it links the data to simultaneously assessed depressive symptomatology. a representative survey on the utili ...200111229623
anxiolytic activity of indian hypericum perforatum linn: an experimental study.the putative anxiolytic activity of 50% ethanolic extract of indian hypericum perforatum (ihp) was investigated in rats using various experimental paradigms of anxiety viz. open field exploratory behaviour (ofb), elevated plus maze (epm), elevated zero maze (ezm), novelty induced suppressed feeding latency (fl) and social interaction (si) tests. pilot studies indicated that single dose administration of ihp had little to no acute behavioural effects, hence the extract of ihp was administered ora ...200011233082
hypericin--a new antiviral and antitumor photosensitizer: mechanism of action and interaction with biological macromolecules.hypericin, a naturally occurring pigment, is found in certain species of plants from the genus hypericum, the most common of which is saint john's wort (hypericum perforatum). recent interest in hypericin is provoked by the discovery that it possesses extremely high toxicity towards certain viruses notably the class of enveloped viruses that includes human immunodeficiency virus (hiv) and toward tumors, and that this toxicity absolutely requires light. consequently, a detailed understanding of t ...200211899265
hypericin photo-induced apoptosis involves the tumor necrosis factor-related apoptosis-inducing ligand (trail) and activation of caspase-8.hypericin (hyp) is a photosensitizing pigment from hypericum perforatum that displays cytotoxic effects in neoplastic cell lines. therefore, hyp is presently under consideration as a new anticancer drug in photodynamic therapy. here, we investigated the mechanism of action of hyp photo-induced apoptosis of jurkat cells compared to the cytostatic drug paclitaxel (pxl). both photoactivated hyp and pxl similarly increased the activity of caspase-8 and caspase-3, and drug-induced apoptosis of jurkat ...200111277999
st john's wort (hypericum perforatum) modulates evoked potentials in guinea pig hippocampal slices via ampa and gaba receptors.the effects of an ethanolic extract of the plant hypericum perforatum l. (st john's wort) (hyp) and its hydrosoluble fraction (hypws) on electrically evoked population spikes and fepsp were investigated in this study. concentration dependent (10(-6) to 10(-4) g/l) excitatory effects were found. above concentrations of 10(-3) g/l, hyp reduced the evoked responses, whereas hypws further increased them. paired pulse facilitation was unaffected with hypws (10(-4) to 10(-2) g/l). the excitatory effec ...200212007672
antidepressant activity of hyperforin conjugates of the st. john's wort, hypericum perforatum linn.: an experimental study.nine extracts of h. perforatum, containing hyperforin in conjugated forms, but devoid of free hyperforin and adhyperforin, were subjected to antidepressant screening using the forced swim test (fst). the observed activity was compared with that of sjw extracts containing hyperforin and adhyperforin (in free form). results indicate that hyperforin conjugates exhibit significant antidepressant activity as evidenced by the reduced immobility period in the fst in rats.200112018529
serotonin, norepinephrine and dopamine involvement in the antidepressant action of hypericum perforatum.hypericum perforatum is considered an effective alternative to the synthetic antidepressants in the treatment of mild-to-moderate depression. recently, we showed that the effects on neurotransmitter contents in different brain regions of laboratory animals are more evident after administration of hypericum extracts containing a higher concentration of flavonoids, thus suggesting that these compounds are important in the antidepressant action of hypericum perforatum. we studied the effects of ph- ...200111302563
[st. john's wort (hypericum perforatum l.). a plant with relevance for dermatology].saint john's wort (hypericum perforatum l.) is a herbal remedy that is effective in the treatment of mild to moderate depression. in traditional folk medicine, oily extracts of st. john's wort are used for topical treatment of wounds, burns and myalgia. the lipophilic phloroglucin-derivative hyperforin has antibacterial and antiinflammatory effects. these effects could be of relevance in topical treatment of infected wounds and other dermatoses, but no studies have been conducted so far. the nap ...200212063742
effects of a methanolic extract and a hyperforin-enriched co2 extract of hypericum perforatum on alcohol intake in rats.hypericum perforatum extracts (hpe) inhibit ethanol intake in rats. hypericin and hyperforin have been proposed as major active principles of hpe. the present study compared the effect on ethanol intake in alcohol-preferring rats of two hypericum perforatum extracts: a methanolic extract containing 0.3% hypericin and 3.8% hyperforin (hpe1) and a co2 extract (hpe2) with 24.33% hyperforin and very low hypericin content. freely feeding and drinking rats were offered 10% ethanol 2 h/day and hpe were ...200111373255
[recent plant poisoning in ruminants of northern and eastern germany. communication from the practice for the practice].it is reported of botanical intoxications in 1379 ruminants (dairy cattle, beef cattle and ewes) in north-eastern germany. the intoxications of these animals were caused by consumption of the following plants: meadow saffron (colchicum autumnale l.), cowbane (cicuta virosa l.), sweet clover (melilotus alba med.), sheep's sorrel (rumex acetosella l.), bracken (pteridium aquilinum kuhn) and st. john's wort (hypericum perforatum l.). in all the five described cases animals died as a result of plant ...200111413718
effect of st. john's wort on free radical production.st. john's wort (hypericum perforatum) is an herbal compound used in the treatment of burns, bruises, swelling, anxiety, and most recently, mild to moderate depression. the present study was designed to evaluate the antioxidant properties of st. john's wort in both cell-free and human vascular tissue. the experiment was performed initially in a cell-free system using krebs buffer and a combination of xanthine/xanthine oxidase to initiate the production of the superoxide radical. additionally, hu ...200111441908
an investigation into the acute nootropic effects of hypericum perforatum l. (st. john's wort) in healthy human volunteers.hypericum perforatum l. (st. john's wort) is a complex herb that has been used for centuries for its putative medicinal properties, and has current therapeutic relevance as a treatment of mild to moderate depression. recently, two studies in rodents have suggested that hypericum may also have memory-enhancing effects. it has a complex pharmacology, in that acute administration modulates numerous neurotransmitter systems that have previously been observed to either augment or impair a variety of ...200111485054
herbal medications for common ailments in the elderly.the popularity of herbal medicine is at an all time peak. this article provides an overview of systematic reviews of herbal treatments for conditions common in elderly individuals. according to this evidence, there is little doubt that hypericum perforatum (st john's wort) is well tolerated and effective for mild to moderate depression. although widely used, valeriana officinalis (valerian) has not been shown beyond reasonable doubt to be effective for insomnia. there is relatively compelling ev ...199910641953
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