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PubMed2001

The effects of St John's wort (Hypericum perforatum) on human cytochrome P450 activity.

BACKGROUND: 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. METHODS: Twelve healthy subjects (5 female, 7 male) completed this 3-period, open-label, fixed schedule study. Tolbutamide (CYP2C9), caffeine (CYP1A2), dextromethorphan (CYP2D6), oral midazolam (intestinal wall and hepatic CYP3A), and intravenous midazolam (hepatic CYP3A) were administered before, with short-term St John's wort dosing (900 mg), and after 2 weeks of intake (300 mg 3 times a day) to determine CYP activities. RESULTS: Short-term administration of St John's wort had no effect on CYP activities. Long-term St John's wort administration caused a significant (P <.05) increase in oral clearance of midazolam from 121.8 +/- 70.7 to 254.5 +/- 127.8 and a corresponding significant decline in oral bioavailability from 0.28 +/- 0.15 to 0.17 +/- 0.06. In contrast to the >50% decrease in the area under the plasma concentration-time curve (AUC) when midazolam was administered orally, long-term St John's wort administration caused a 20% decrease in AUC when midazolam was given intravenously. There was no change in CYP1A2, CYP2C9, or CYP2D6 activities as a result of St John's wort administration. CONCLUSION: Long-term St John's wort administration resulted in a significant and selective induction of CYP3A activity in the intestinal wall. St John's wort did not alter the CYP2C9, CYP1A2, or CYP2D6 activities. Reduced therapeutic efficacy of drugs metabolized by CYP3A should be anticipated during long-term administration of St John's wort.

Administration, Oral↗
PubMed2001

[Hyperici herba (Hypericum perforatum L].

The aim of the author was to introduce the pharmacologically active compounds of Hyperici herba and their therapeutic effects. The extraction procedures and the possible interactions of Hypericum preparations with different drugs were also studied.

Anthracenes↗
PubMed2001

[Experimental cultivation of Hypericum perforatum L. in Bratislava].

Experiments in small plots were performed to cultivate Hypericum perforatum L. var. angustifolium DC on light soil and at a sunny location in Bratislava. In the 1st year of vegetation the herb was not harvested. Harvests were made in the 2nd and 3rd years of vegetation and later plants died. In the course of the vegetation year it was possible to carry out three harvests on the rule. The 1st one was made just prior to blooming or at the stage of the onset of blooming, and only the blooming top parts were collected. The yield of the dry tops varied in dependence on the vegetation year, conditions of the location, age of the plants, and the date of the 1st harvest. From the two-years old plants, a whole-year yield of 8.12-14.87 kg. 10 m-2 of dry tops and from the three-years old plants, 8 kg.10 m-2, was obtained. The content of hypericin varied from 0.06 to 0.13%, and 60% ethanol extracted 21.7-27.9% of substances.

Anthracenes↗
PubMed2002

The separation of hypericine and pseudohypericine from Hypericum perforatum L.

The extraction of Hypericum perforatum L. was carried out by the method of ultrasonic maceration. The separation of H. perforatum L. extract in order to obtain hypericine and pseudohypericine rich fractions was carried out by the following chromatographic methods: flash column chromatography, high speed countercurrent chromatography, XAD solid phase extraction and Sephadex column chromatography. The separation by the Sephadex column chromatography gave the best results. Preparative HPLC was used to isolate hypericine and pseudohypericine from fraction 4 obtained by the Sephadex column chromatography procedure.

Anthracenes↗
PubMed2000

[Study on the callus and cell culture of Hypericum perforatum].

Callus were induced from the leaves and stems of Hypericum perforatum L. The cell suspension culture and plate culture were also investigated in this paper. The results showed that the medium of MS which contained 2,4-D 1 mg/L and NAA 1 mg/L was the best one for inducing callus. The plant growth regulator of 2,4-D was assential for callus and suspension culture. Factors such as the time of cell suspension culture, the ways of plating and cell density, which affects the plating efficency were studied. The results showed that plating at density of 5 x 10(3) cells/ml and with monocells seperated from the cells cultured 14-21 days, high plating efficiency could be obtained either by conditional plate culture or by nursing plate culture.

Cell Culture Techniques↗
PubMed2003

[Therapeutic and toxicologic aspects of biological effects of Saint John's wort (Hypericum perforatum L.)].

Saint-John's-wort (Hypericum perforatum L.) has been used in traditional medicine since time immemorial and it has its position also in the contemporary list of medicinal plants of pharmaceutical importance. Though it originally comes from Europe and Asia, it has been domesticated and, thanks to its properties, has been cultivated in many other parts of the world. The herbaceous plant contains a wide spectrum of substances, out of which anthraglycosides, flavonoids, and floroglucin derivatives participate in principal pharmacological effects. In recent years this plant has become greatly popular as an effective alternative means for the treatment of weak to medium forms of depression. Large quantities of mass-produced drugs with its extract are sold mainly in the United States and Germany and successfully penetrate into the markets of other European countries including the Czech Republic. Some adverse side-effects are also connected with the plant, the best known being photosensitivity, lesser known being its interactions with other drugs or foodstuffs. The present review aims to process literary references concerning the biological activities of the plant and point out its most important therapeutic and toxicological aspects.

Animals↗
PubMed2003

Effects of Hypericum extract on the acetylcholine release: a loose patch clamp approach.

The St. John's Wort (Hypericum perforatum) extract (Hp) represents one of the most useful natural therapeutic agents in the treatment of moderate and mild depression. The antidepressant effects of Hp are different, by a molecular mechanism point of view, when compared to those of other antidepressant drugs and, we think, a further pharmacological characterization is needed. It is suggested that the neurochemical effects of Hp could be bind either to its activity on the uptake of some mediators in the central nervous system or to the inhibition of some enzymatic activity at the receptor level. The present study carried out with the loose patch clamp (LPC) in the mouse neuromuscular junction, indicates a potentiation of the acetylcholine (ACh) action at the mouse neuromuscular junction. The spontaneous release of ACh was unaffected by Hp indicating that neither presynaptic nor postsynaptic function are modified by Hp. Indeed, both the frequency and the amplitude of the miniature end-plate currents (mepcs) were unmodified by Hp. Furthermore, the mepcs decay time (tau), i.e. the apparent cholinergic channel life time, was significantly increased after Hp treatment. The other parameter affected was the amplitude of the evoked end-plate currents (epcs) which was constantly and in a dose dependent manner increased by Hp. These findings suggest a possible action of Hp on the acetylcholinesterase (AChE) in terms of a reduction of the degradation rate of ACh.

Acetylcholine↗
PubMed2004

The antidepressant activity of Hypericum perforatum L. measured by two experimental methods on mice.

The pharmacological approach to the treatment of depression includes a long-term employment of antidepressants, either in the form of monotherapy or as a combination of several antidepressants with various mechanisms of action. Hypericum perforatum L. (St. John's wort) is the only natural antidepressant. Several constituents of the extract, such as hypericin and hyperforin, seem to be important for this effect. H. perforatum is considered to be an effective alternative to other therapeutic agents in the treatment of mild to moderate depression. The paper describes the investigation of the antidepressant effect of H. perforatum (doses 7, 35 and 70 mg kg(-1) b. m.) on mice using the forced-swimming and tail-suspension methods. As an indicator of the antidepressant effect, it was shown that the immobility time of animals in the forced-swimming and tail-suspension experiments was shorter, i.e. the activity of the animals was higher. With single doses of extract suspension increasing from 7 over 35 to 70 mg kg(-1) the antidepressant effect increased in proportion by 10.1%, 25.8% and 38.6% in the swimming method, and by 12.7%, 16.5% and 24.5% in the tail-suspension method compared to controls. H. perforatum extract displays dose-dependent antidepressant effect at a dose as low as 7 mg kg(-1). Both models have proved to be equally valuable for demonstration of substances with a potential antidepressant effect.

Animals↗
PubMed2004

[Quantitative analysis of active substances in St. John's wort (Hypericum perforatum L.) by the high performance liquid chromatography method].

The flavonoids (rutin, quercetin, and isoquercetin) and hypericin are the main active substances of St. John's wort (Hypericum perforatum). They support regeneration of human body cells, provide disinfection, and act as antidepressant, antiviral, and anti-inflammation tools. Such large spectrum of the applicable functions depends on the quantity of each substance. The objective of this paper is to determine the regularities of the quantitative variation of rutin, quercetin, isoquercetin and hypericin in flowers and leaves of St. John's wort in different habitats and different plant development phases. Plant material for the quantitative analysis was collected in 1998-1999. The high performance liquid chromatography (HPLC) was applied for the quantitative analysis of the active substances in St. John's wort. The flavonoids (rutin, quercetin, and isoquercetin) were identified under the UV waves of 254 nm, and hypericin - under the waves of 590 nm. Larger quantities of rutin were found in leaves, while those of quercetin, isoquercetin and hypericin - in flowers of St. John's wort. The highest accumulation of active substances was observed during the development of flowering buds and in flowering time. The quantitative variation of active substances in different habitats allows the selection of the best plant samples for their cultivation and conservation in field collections.

Anthracenes↗
PubMed2004

[Determination of hyperin in genus Hypericum medicinal plants].

OBJECTIVE: To compare the content of hyperin in Hypericum medicinal plants. METHODS: HPLC method was established. Alltima C18 radial compression column was used with a mobile phase of methanol-0.5% phosphoric acid (45:55, adjusted to pH = 3.0 with triethylamine). The detecting wavelength was 360 nm. Flow rate was 0.8 ml/min, external standard method was quantitative analysis method. RESULTS: The linear range was 0.101-2.023 microg. The average recovery was 96.527%. The result showed that the content of hyperin in H. perforatum, H. forrestii was higher than that of others (1.257% and 0.461% respectively). CONCLUSION: This method provides an accurate and sensitive way in detecting hyperin.

Chromatography, High Pressure Liquid↗
PubMed2004

[Determination of elements of hypericum perforatum L. in Xinjiang by microwave digestion-ICP-AES].

Sample digestion by microwave is of some merits: simple, rapid, saving agents, nonpollution and being easy digested. HNO3-HClO4 (5:1) was used as a microwave digestion agent. A direct method is reported for the determination of Fe, Ca, Mg, Zn, Mn, Cu, Na, K, Ba, Al, Pb and Cr in Hypericum perforatum L. in Xinjiang by inductively coupled plasma atomic emission spectrometry(ICP-AES). The selection of digestion conditions of the technique is described. The recoveries for these elements were 93.2%-103.0%, and the relative standard deviation (RSD) of the twelve samples were 0.4%-2.9%. According to standard sample GBW07602 bush twigs and leaves, the authors checked the method for accuracy and precision. The results were found to be basically consistent with the reference values. It was proved that the method features satisfactory precision and accuracy. The method was applied to the determination of plant materials with good agreement.

Aluminum↗
PubMed2005

[Experimental study of the total flavonoid in Hypericum perforatum on depression].

OBJECTIVE: To investigate pharmacological effects of the total flavonoid in Hypericum perforatum on depression. METHOD: Experimental depression was induced by subcutaneous injection of reserpine in mice. The concentration of monoamine transmitters including 5-HT and NE, the activity of monoamine oxidase (MAO) in brain and reserpine-induced symptoms of depression, such as ptosis, attenuation of autonomous activity, behavioral despair, acquired helplessness and sleep, were measured respectively to evaluate the effects of the total flavonoid in H. perforatum on the depression. RESULT: The total flavonoid in H. perforatum significantly decreased the activity of MAO, inhibited the ptosis and the attenuation of autonomous behavior induced by reserpine respectively. The levels of 5-HT and NE were also attenuated by the total flavonoid in H. perforatum remarkably. In addition, the total flavonoid in H. perforatum was shown to inhibit behavioral despair and acquired helplessness and to prolong the sleep time in the mice. Following the treatment with the total flavonoid in H. perforatum, 5-THP, at the dosage without any side-effects, caused the tremble in the mice. CONCLUSION: The results indicate that total flavonoid in H. perforatum can significantly inhibit the depression.

Animals↗
PubMed2005

[Study on the chemical constituents in herb of Hypericum attenuatum].

OBJECTIVE: To study the constituents of Hypericum attenatum. METHOD: The compounds were isolated by chromatography on silica gel, the structures were identified by their physical, chemical properties and IR, NMR and MS spectral data respectively. RESULT: Nine compounds were isolated and identified as p-hydroxybenzoic acid (1), 6, 9-dihydroxy-4, 7-megastigmadien-3-one (2), butyl alcohol-O-alpha-D-fructoside (3), 24-ethyl-cholest-7-ene-3 beta, 5 alpha, 6 beta-thtroil (4), hexanol (5), 1 beta, 6 alpha-dihydroxyeudesmane-4(14)-ene (6), beta-sitosterol (7), 5, 5-dimethyl-4-hydroxy-tetrahydrofuran-2-one (8), beta-daucosterol (9). CONCLUSION: All of the compounds were isolated from H. attenuatum for the first time.

Hexanols↗
PubMed2006

Phytochemical analysis of nine Hypericum L. species from Serbia and the F.Y.R. Macedonia.

The methanol extracts of the aerial parts of nine Hypericum species (H. barbatum, H. hirsutum, H. linarioides, H. maculatum, H. olympicum, H. perforatum, H. richeri, H. rumeliacum and H. tetrapterum), collected on different locations in Serbia and the F.Y.R. Macedonia, were obtained by accelerated solvent extraction (ASE) and analyzed for the content of four constituents (hyperoside, quercitrin, hyperforin and hypericin) by LC-MS/ MS. All studied extracts contained the characteristic four constituents, but their contents varied between different species and locations. The content of hypericin in H. barbatum was significantly higher (3.9 times) than that in H. perforatum.

Chromatography, High Pressure Liquid↗
PubMed2006

[Evaluation of preparing process of extract of hypericum perforatum using HPLC fingerprint analysis].

OBJECTIVE: To establish the quality control method of the extract enriched hypericins and flavonoids (HFEE) prepared from Hypericum perforatum by means of HPLC fingerprint analysis, and to evaluate the validity, stability of within-day and between-day of the preparing process of HFEE as well as the influence of antioxidant and the herbal source to the quality of HFEE. METHOD: HPLC-UV-MS was employed to the qualitative and quantitative analyses of HFEE. RESULT: Ten peaks on the HPLC fingerprint of HFEE were indicated, and eight compounds of them had been identified. With respect of the preparing process of HFEE, the validity and stability were significantly observed. There was almost no effect observed on the quality of HFEE whether or not adding the antioxidant during the process. However, different parts of the plant collected as the materials could significantly affect the quality of HFEE. CONCLUSION: The method established in the present study is convenient, reliable, and could be used for the quality control of the extract of H. perforatum and for the monitor and control of the preparing process of the extract.

Anthracenes↗
PubMedDate not supplied

[The influence of some elicitors on growth and morphogenesis of Hypericum perforatum callus cultures].

We studied the effects of elicitors, such as mannan, beta-1,3-glucan, ancymidol, and cork crumbs, on morphogenetic and biosynthetic potencies of shoot cultures of Hypericum perforatum L. In the presence of these elicitors, different morphogenetic structures of H. perforatum callus cultures were formed. A correlation was found between the morphogenetic processes and induction of hypericin and pseudohypericin biosynthesis in the callus cultures.

Anthracenes↗
PubMed1995

Antibacterial phloroglucinols and flavonoids from Hypericum brasiliense.

Three known phloroglucinols (japonicine A, uliginosin A and isouliginosin B) and a new phloroglucinol (hyperbrasiol A) have been isolated from a petrol extract of the leaves and flowers of Hypericum brasiliense. Their structures were established by spectroscopic methods (UV, DCI-MS, 1H and 13CNMR, including SINEPT, HMBC, HSQC, DQFCOSY experiments). The substitution pattern of hyperbrasilol A was confirmed by X-ray crystallography. All four phloroglucinols were antibacterial against Bacillus subtilis in a TLC bioautographic assay. The flavonoids, kaempferol, luteolin, quercetin, quercitrin, isoquercitrin, hyperoside and guaijaverin, were isolated from a methanol extract of the same organs.

Anti-Bacterial Agents↗
PubMed1996

Xanthones from Hypericum roeperanum.

Four new xanthones have been isolated from the roots of Hypericum roeperanum. Their structures have been established by a combination of spectroscopic and chemical methods as 1,6-dihydroxy-5-methoxy-4',5'-dihydro-4',4',5'-trimethylfurano- (2',3':3,4)-xanthone (5-O-methyl-2-deprenylrheediaxanthone B), 1,6-dihydroxy-5-methoxy-6',6'-dimethylpyrano-(2',3':3,4)-xanthone (5-O-methylisojacareubin), 1,3,5,6-tetrahydroxy-2-(2',2'-dimethyl-4'-isopropenyl)-cyclopen tanylxanthone (5-O-demethylpaxanthonin) and 1,3,5,6-tetrahydroxy-4-trans-sesquilavandulylxanthone (roeperanone). In addition, 2-hydroxyxanthone, 5-hydroxy-2-methoxyxanthone, 1,5-dihydroxy-2-methoxyxanthone, 2-deprenyl rheediaxanthone B, isojacareubin and calycinoxanthone D have been isolated and characterized. Some of the isolated xanthones exhibited antifungal activity against Candida albicans.

Antifungal Agents↗