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 weight with concomitant decrease in spleen weight. Chronic stress also suppressed male sexual behaviour, induced behavioural depression (Porsolt's swim despair test and learned helplessness test) and cognitive dysfunction (attenuated retention of learning in active and passive avoidance tests). All these FSS induced perturbations were attenuated dose dependently by IHp (100 and 200 mg/kg, po) and PG (100 mg/kg, po). The results indicate that IHp has significant anti-stress activity, qualitatively comparable to PG, against a variety of behavioural and physiological perturbations induced by chronic stress, which has been proposed to be a better indicator of clinical stress than acute stress, and may indicate adaptogenic activity.     

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 the standard anti-inflammatory drug. Pentazocine (10 mg/kg, ip) and aspirin (25 mg/kg, ip), both clinically used analgesics, were used as standard analgesics for comparison. IHp extract showed significant anti-inflammatory and analgesic activity at both dose levels, in all the paradigms used. Additionally, IHp potentiated the anti-inflammatory activity of indomethacin and analgesic activities of pentazocine and aspirin.     

Pharmacodynamic study of Hypericum perforatum L.

The effects of Hypericum perforatum L. (Hypericaceae) crude ethanol extract (A), ethyl acetate extract (B), aqueous extract (C) and infusion (I), on pentobarbital induced sleeping time, intestinal motility, and their analgesic activity, have been investigated. Extracts A and B exhibited significant stimulatory and antidepressant effects on the CNS. Both extracts prolonged sleep, increasing time up to more than 25 min. The antidepressive activity of extract A was also achieved by significant reduction of the myorelaxant activity of diazepam. Extract B exhibited strong analgesic activity reducing abdominal stretching induced by acetic acid by nearly 50 %. Extracts A, B and C exhibited spasmolytic activity, significantly reducing intestine motility.     

In vitro pollen germination in Hypericum perforatum L. and Hypericum rumeliacum Boiss

In vitro pollen germination and pollen tube growth investigations are valuable tools used in identification of the effects of environmental factors and genotypic differences on pollen viability, pollen germination and tube elongation. In this study pollen viability, in vitro pollen germination capacity, abnormality ratios and tube length in germinated pollens of Hypericum perforatum L. and H. rumeliacum Boiss. were investigated. Both of these species has spheroid-shaped and tricolporate pollen grains. The diameters of Hypericum perforatum and H. rumeliacum pollens were found as 24 +/- 3 microm and 19 +/- 2 microm, respectively. Pollen viability of H. perforatum and H. rumeliacum was found as 83% and 72%, respectively. The germination percentages were found as 12.85% for H. perforatum and 64.42% for H. rumeliacurm. Tube lengths in germinated pollens of both taxa were measured approximately as 95.25 +/- 38 microm in H. perforatum and 165.92 +/- 53 microm in H. rumeliacium 4 h after inoculation. In germinated pollen grains of H. perlbratum and H. rumeliacumn abnormality percentages were determined as 13.23% and 43.97%, respectively. In germinated pollens of these two species, highly significant (P < 0.00001) differences in in vitro germination percents and abnormality percents were observed. Abnormalities such as swollen tube tip, branched tube, spiralled tube and excessive tube formation were observed in pollen tubes. The results of this study showed that there were obvious differences in pollen germinability between these two species growing under the same environmental conditions.     

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 levels of serotonin (5-HT) and its metabolite 5-hydroxy indole acetic acid (5-HIAA) and 5-HT turnover in all the brain regions assayed. On the other hand, IHp treatment significantly augmented the levels of norepinephrine (NE) and its metabolite methylhydroxy phenyl glycol (MHPG) and NE turnover in all the brain regions studied. Similarly, the levels of dopamine (DA) were also significantly augmented in the hypothalamus, striatum and frontal cortex. Likewise, the levels of dihydroxyphenyl acetic acid (DOPAC), the major metabolite of DA, were also increased in these brain areas. Pharmacological studies with IHp extract have shown two major behavioural actions, namely, anxiolytic and antidepressant effects. The present findings tend to rationalise these observations, reduced 5-HT activity being consonant with anxiolytic and increased NA and DA activity being consonant with antidepressant action.     

Anti-influenza A virus effect of Hypericum perforatum L. extract

To study the antiviral effect of Hypericum perforatum L. extract (HPE) on influenza A virus (IAV) (H₁N₁) in vitro and in vivo. Cytopathic effect (CPE) and neutral red (NR) dye uptake were used to examine the antiviral effect of HPE on Madin Darby Canine Kidney (MDCK) cells which were infected with IAV in vitro. HPE was effective against influenza A virus (IAV) in vitro, with a 50% effective concentration (EC₅₀) of 40 μg/mL. The mean 50% cytotoxic concentration (CC₅₀) in the MDCK used in these experiments was 1.5 mg/mL. Ribavirin was run in parallel with EC₅₀ values of 5.0 μg/mL; the mean CC₅₀ for ribavirin was 520 μg/mL. Oral gavage administrations of HPE or ribavirin to mice infected with the IAV were highly effective in preventing death, slowing the decline of arterial oxygen saturation, inhibiting lung consolidation and reducing lung virus titers. The minimum effective dose of HPE in these studies was 31.25 mg/kg/day, which was administered twice daily for 5 d beginning 4 h prior to virus exposure. Below a dosage of 2000 mg/kg/day, almost all treated mice survived, which suggests that HPE is of low toxicity. Ribavirin’s minimum effective dose was 40 mg/kg/day with the LD50 determined to be 200 mg/kg/day. Delay of the initiation of either HPE or ribavirin therapy, using approximately 1/3 LD₅₀ dose each time, could still be protective as late as 48 h after exposure to the IAV. While both agents appeared to have similar efficacy against IAV infections, HPE was considered to be less toxic and may warrant further evaluation as a possible therapy for influenza. Foundation items: One Hundred Person Project of The Chinese Academy of Sciences (2008-287); The Project of Basic Scientific Research Fund for Central Public-Welfare of Institute of Sciences (BRF070402).     

Anti-Influenza A Virus Effect of Hypericum perforatum L. Extract

To study the antiviral effect of Hypericum perforatum L. extract (HPE) on influenza A virus (IAV) (H1N1) in vitro and in vivo. Cytopathic effect (CPE) and neutral red (NR) dye uptake were used to examine the antiviral effect of HPE on Madin Darby Canine Kidney (MDCK) cells which were infected with IAV in vitro. HPE was effective against influenza A virus (IAV) in vitro, with a 50% effective concentration (EC50) of 40 μg/mL. The mean 50% cytotoxic concentration (CC50) in the MDCK used in these experiments was 1.5 mg/mL. Ribavirin was run in parallel with EC50 values of 5.0 μg/mL; the mean CC50 for ribavirin was 520 μg/mL. Oral gavage administrations of HPE or ribavirin to mice infected with the IAV were highly effective in preventing death, slowing the decline of arterial oxygen saturation, inhibiting lung consolidation and reducing lung virus titers. The minimum effective dose of HPE in these studies was 31.25 mg/kg/day, which was administered twice daily for 5 d beginning 4 h prior to virus exposure. Below a dosage of 2000 mg/kg/day, almost all treated mice survived, which suggests that HPE is of low toxicity. Ribavirin's minimum effective dose was 40 mg/kg/day with the LD50 determined to be 200 mg/kg/day. Delay of the initiation of either HPE or ribavirin therapy, using approximately 1/3 LD50 dose each time, could still be protective as late as 48 h after exposure to the IAV. While both agents appeared to have similar efficacy against IAV infections, HPE was considered to be less toxic and may warrant further evaluation as a possible therapy for influenza.     

Antilipoxygenase activity of compounds from Hypericum perforatum

The main biologically active constituents of Hypericum species are flavonoids (quercetin, isoquercitrin, hyperoside, rutin), biflavonoids and naphthodianthrones (hypericin, pseudohypericin). Lipoxygenase is the key enzyme in the biosynthesis of leukotriens, which have been postulated to play an important role in the pathophysiology of several inflammatory and allergic diseases. This work deals with the investigation of potential antilipoxygenase activity of different compounds and extracts isolated from Hypericum perforatum L. The highest inhibitory effect was exhibited by flavonoid derivative hyperoside (IC₅₀ 5.768 × 10⁻⁶ M). Acetone and ethanolic extracts caused also an inhibition of lipoxygenase. On the basis of inhibitory effect of compounds tested we assume that the most of them may be involved in the antiinflammatory principles of Hypericum perforatum L.     

激素对贯叶连翘器官分化的影响

贯叶连翘 (ＨｙｐｅｒｉｃｕｍｐｅｒｆｏｒａｔｕｍＬ .)为多年生草本 ,中国民间主要用于止血、抗炎、妇科病等[1] ,欧洲民间用于治疗创伤也有相当长的历史。近年来 ,欧、美等国家和地区将其应用于抑郁症的治疗 ,取得了很好的疗效。 80年代后期 ,由于发现该植物体内含有显著抗     

Identification and genetic analysis of the APOSPORY locus in Hypericum perforatum L.

The introduction of apomixis – seed formation without fertilization – into crop plants is a long‐held goal of breeding research, since it would allow for the ready fixation of heterozygosity. The genetic basis of apomixis, whether of the aposporous or the diplosporous type, is still only poorly understood. Hypericum perforatum (St John’s wort), a plant with a small genome and a short generation time, can be aposporous and/or parthenogenetic, and so represents an interesting model dicot for apomixis research. Here we describe a genetic analysis which first defined and then isolated a locus (designated HAPPY for H ypericum AP OSP ORY ) associated with apospory. Amplified fragment length polymorphism (AFLP) profiling was used to generate a cleaved amplified polymorphic sequence (CAPS) marker for HAPPY which co‐segregated with apospory but not with parthenogenesis, showing that these two components of apomixis are independently controlled. Apospory was inherited as a dominant simplex gene at the tetraploid level. Part of the HAPPY sequence is homologous to the Arabidopsis thaliana gene ARI7 encoding the ring finger protein ARIADNE7. This protein is predicted to be involved in various regulatory processes, including ubiquitin‐mediated protein degradation. While the aposporous and sexual alleles of the HAPPY component HpARI were co‐expressed in many parts of the plant, the gene product of the apomict’s allele is truncated. Cloning HpARI represents the first step towards the full characterization of HAPPY and the elucidation of the molecular mechanisms underlying apomixis in H. perforatum.     

Effect of the number of rol genes integrations on phenotypic variation in hairy root-derived Hypericum perforatum L. plants

The extent of phenotypic variation of St. John's wort (Hypericum perforatum L.) plants transformed with wild agropine ATCC 15834 Agrobacterium rhizogenes plasmid was evaluated with respect to the number of rol genes integrations. The transfer of T(L)-DNA to plant explants during each transformation event was incomplete with different rolA, rolB, and rolC copy numbers. Along with typical features representing the hairy root syndrome, an altered size, number and density of dark and translucent glands, changes in ability to synthesize secondary metabolites, and reduced fertility were observed. The highest copy number of transferred rol genes resulted in weak expression of transgenic character and comparable quantitative parameters with the controls. Only 1 out of 11 transgenic clones was able to produce seed progeny and not more than 4 out of its 35 offsprings were positive for rolC gene integration. Sterility of the clones was due to retarded development of both gametophytes.     

Identification and quantification of phenolic compounds in Hypericum perforatum L. transgenic shoots

Regeneration of transgenic shoots was achieved from Hypericum perforatum L. hairy roots on hormone-free MS/B₅ medium for a period of 4 weeks under a photoperiod of 16-h light. A control experiment was set up with root segments obtained from in vitro grown seedlings. Investigations have been made to study the production of phenolic compounds in non transgenic and transgenic shoot cultures. Six groups of phenolic compounds such as phenolic acids, flavonols, flavan-3-ols, naphtodianthrones, phloroglucinols, and xanthones were recorded in the transgenic shoots. Chlorogenic acid was found as the most representative phenolic acid in shoot extracts. With regard to the class of quercetin derivatives in transformed shoots, quercetin 6-C-glucoside usually dominated among the glycosides followed by quercitrin and hyperoside. The analysis of flavan-3-ols in transgenic shoots resulted in the identification of epicatechin and proanthocyanidin dimers. One of the main achievements in this study was considerably enhanced hypericin and pseudohypericin production in transgenic shoots. The concentration of identified naphtodianthrones was about 12-fold higher in transformed shoots compared to control. Chromatographic analysis of phloroglucinols in transgenic shoots resulted in the identification of hyperforin, while its homolog adhyperforin was detected in traces. A twofold higher content of hyperforin was observed in transgenic shoots compared to control. Although mangiferin was found as the main representative xanthone in shoot extracts, several other xanthones identified as γ-mangostin isomers, trihydroxy-1-methoxy-C-prenyl xanthone, garcinone E, and banaxathone E were de novo synthesized in transformed shoots. Therefore, H. perforatum transgenic shoots could be considered as a source for rapid and increased production of naphtodianthrones and other specific phenolic compounds.     

Genetic and biochemical analysis of Hypericum perforatum L. plants regenerated after cryopreservation

Shoot-tips from in vitro cultured Hypericum perforatum L. genotypes were subjected to assessments of developmental competence, genetic stability, and biosynthetic ability to identify critical points during cryopreservation. Survival rate, chromosome number stability, alteration in VNTR sequences and hypericin content were evaluated, in plants after pre-culture, and two subsequent cryogenic steps (cryoprotection and cooling) and those recovered from cryopreserved meristems. Pre-culture and cryoprotection treatments, did not reveal any significant differences, in these studied characteristics. Genetic stability was assessed by chromosome counts and analysis of variability in the VNTR sequences. No changes in chromosome number were detected in comparison with the untreated control but minor alterations were revealed in non-coding sequences. The content of hypericin after the recovery of cryopreserved meristems remained comparable with the unfrozen control. The controlled rate freezing technique used for cryopreservation was relevant for restoration of genetic and biochemical stability in Hypericum perforatum L. shoot-tips.     

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 200 mg/kg, p.o.) once daily for three consecutive days, while imipramine (15 mg/kg, i.p.), a clinically used antidepressant agent, was administered acutely to rats (CF strain, 150 +/- 10 g) and mice (Wistar strain, 23 +/- 2 g) of either sex as the standard drug. Controls animals were treated similarly with equal volume of vehicle (0.3% carboxymethyl cellulose). Indian Hypericum perforatum extract showed significant antidepressant activity on all the paradigms of depression used. Thus IHp and imipramine treatments significantly reduced the immobility time in BD and TS tests. Significant reduction in escape failures was also observed in LH test. In RIH test IHp and imipramine inhibited reserpine induced hypothermia in a dose dependent manner. The observed antidepressant activity of IHp was qualitatively comparable to that induced by imipramine.     

Morphoregulatory effect of plant growth regulators on Hypericum perforatum L. Seedlings

The morphogenetic response of Hypericum perforatum seedlings to different auxin and cytokinin concentrations was studied. A stimulation of the concentration-dependent rooting ability was observed under the influence of indole-3-acetic acid and indole-3-butyric acid. Rooting was not enhanced by the effects of 2,4-dichlorophenoxyacetic acid and 1-naphtaleneacetic acid. Differentiated roots were isolated and cultured in liquid media with the same combination of growth-promoting auxins. Chromosome counts in root tip cells after long-term cultivation indicated a high degree of chromosomal instability. Multiple shoot formation occurred under the influence of 6-benzylaminopurine and kinetin. Adenine and 6-(γ,γ-dimethylallylamino)-purine did not stimulate shoot differentiation. No differences in the morphogenetic response to auxins and cytokinis were detected between diploid and tetrapoloid plants.     

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 adhyperforin inhibited binding of the cocaine analogue, [3H]WIN 35,428 to the dopamine transporter. However, the known antidepressives imipramine, nomifensine and fluoxetine all inhibited binding of [3H]WIN 35,428, indicating that hyperforin and adhyperforin do not bind to the same site on the dopamine transporter as these compounds. Furthermore, hyperforin and adhyperforin did not prevent dopamine binding, but inhibited dopamine translocation. Our studies further support recent reports suggesting that the effect of hyperforin on uptake of monoamines is probably not caused by a direct effect of hyperforin on known sites on the transporters.     

Correlation between hypericin content and the ploidy of somaclones of Hypericum perforatum L.

An altered ploidy level was observed in plants regenerated by adventitious shoot formation from seedlings of Hypericum prformatum L. (2n = 4x = 32). Among the somaclones of the R_o generation, the presence of diploids (2n = 2x = 16), triraploids (2n = 3x = 24), tetraploids (2n = 4x = 32) and mixoploids was detected. Cytogenetic analyses of the R₁ and R₂ progenies showed that the chromosomal instability of the R_o somaclones was transferred onto the next generation. While almost all the seed progeny of diploids (100% in R¹ and 94% in R₂) progenies showed that the chromosomal instability of the R_o somaclones was transferred onto the next generations. While almost all the seed progeny of diploids (100% in R¹ and 94% in R²) and more than 60% of tetraploids (61% in R₁ and 73% in R₂) retained their chromosome number, cytogenetic diversity was observed in the progeny of triploids, mixoploids and some tetraploids. Somaclones and their offspring were analyzed for hypericin content. Statistical evaluation showed a correlation between hypericin content and ploidy during a two-year cultivation of R₀ somaclones and in their R₁ and R₂ progenies.     

Composition of the essential oils of Hypericum perforatum L. from southeastern France

The composition of the volatile oils from the aerial parts of Hypericum perforatum L. collected in six localities from southeastern France was analysed by GC-MS. Twenty-nine to 41 compounds have been identified in these volatile oils. The main constituents were sesquiterpene hydrocarbons, and minor variations were pointed out in the oil composition among the six populations. However, the composition of all the analysed oils greatly varied from that of the previous studies, carried out on H. perforatum essential oils from other localities, in which monoterpenoids were the major constituents, particularly, the alpha-pinene.