Hypericum in infection: Identification of anti-viral and anti-inflammatory constituents

Ganoderma lucidum and Hypericum perforatum Exhibit Anti-Inflammatory, Antioxidant, and Anti-Androgen Effect in Rat Model of Experimental Polycystic Ovarian Syndrome

OBJECTIVE

Chronic inflammation is considered to be of key importance in the pathogenesis of polycystic ovarian syndrome (PCOS). Ganoderma lucidum polysaccharide (GLP) and Hypericum perforatum (HP) have been reported to have anti-inflammatory and antioxidant activities. We studied the effects of these agents on ovarian tissue in a rat model of experimental PCOS.

MATERIALS AND METHODS

Forty-two Sprague-Dawley female rats were divided into 6 groups with 7 animals in each group as listed below: Group 1: Control, Group 2: PCOS, Group 3: PCOS + HP, Group 4: HP only, Group 5: PCOS+ GLP, Group 6: GLP only. At the end of the experimental procedures, all the animals underwent bilateral oophorectomy and blood samples were collected. Ovarian tissue and blood samples were used for biochemical and histopathological analysis.

RESULTS

Follicle degeneration in the PCOS group showed a statistically significant increase compared to the other groups (p < 0.05). Cystic follicles were significantly reduced in the PCOS+GLP and PCOS+HP groups as compared to the PCOS group. Levels of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) were elevated in PCOS rats (p < 0.01). Levels of sex hormone binding globulin (SHBG) levels were diminished (p < 0.01). Levels of malondialdehyde (MDA) and insulin-like growth factor 1 (IGF-1) were increased in PCOS rats as compared to the other groups (p < 0.02, p < 0.02, respectively). GLP supplementation diminished the levels of IGF-1 and MDA. GLP or HP supplementation increased reduced glutathione (GSH).

CONCLUSION

GLP and HP treatment normalizes SHBG levels while correcting PCOS-induced hyperandrogenemia. Both herbs regulate the redox balance by decreasing the levels of MDA and increasing the level of GSH.

Phenolic composition, antioxidant, cytotoxic activities and cardioprotective effect of hydroalcoholic extract from aerial-parts of Hypericum attenuatum Fisch. ex Choisy

This study investigated phenolic metabolites, antioxidant, cytotoxic and cardioprotective effects of the hydroalcoholic extract from the aerial parts of Hypericum attenuatum Fisch. ex Choisy. The total phenolic and flavonoid contents of the extract were 132.40 ± 2.06 mg GAE/g and 101.46 ± 1.47 mg QE/g respectively. The extract exhibited antioxidant activities with an EC50 value against DPPH radical of 0.099 ± 0.03 mg/mL and a FRAP value of 1.22 ± 0.086 mmol/L Fe2+. The extract could protect H9c2 cardiomyoblasts from the injury of H2O2, while it restored the H9c2 cell viability to 82.69 ± 2.33% at 100 μg/mL. The extract possessed cytotoxicity on MGC803, C666-1 and SW620 cells with IC50 values of 69.77 ± 2.43 μg/mL, 74.97 ± 1.08 μg/mL and 58.91 ± 1.81 μg/mL, respectively. Moreover, it could promote apoptosis of the tested cancer cells. This research provided useful information for the utilization of H. attenuatum as herbal medicine.

Nanoencapsulation and characterisation of Hypericum perforatum for the treatment of neuropathic pain

AIM

This work aimed to encapsulate Hypericum perforatum extract (HPE) into nanophytosomes (NPs) and assess the therapeutic efficacy of this nanocarrier in neuropathic pain induced by partial sciatic nerve ligation (PSNL).

METHODS

Hydroalcoholic extract of Hypericum perforatum was prepared and encapsulated into NPs by thin layer hydration method. Particle size, zeta potential, TEM, differential scanning calorimetry (DSC), entrapment efficiency (%EE), and loading capacity (LC) of NPs were reported. The biochemical and histopathological examinations were measured in the sciatic nerve.

RESULTS

Particle size, zeta potential, %EE, and LC were 104.7 ± 1.529 nm, -8.93 ± 1.71 mV, 87.23 ± 1.3%, and 53.12 ± 1.7%, respectively. TEM revealed well-formed and distinct vesicles. NPHPE (NPs of HPE) was significantly more effective than HPE in reducing PSNL-inducing pain. Antioxidant levels and sciatic nerve histology were reversed to normal with NPHPE.

CONCLUSIONS

This study demonstrates that encapsulating HPE with phytosomes is an effective therapeutic approach for neuropathic pain.

Production, Characterization, and In Vitro and In Vivo Studies of Nanoemulsions Containing St. John’s Wort Plant Constituents and Their Potential for the Treatment of Depression

The current project was designed to prepare an oil-in-water (oil/water) hypericin nanoemulsion using eucalyptus oil for the preparation of an oil phase with chitosan as an emulsion stabilizer. The study might be a novelty in the field of pharmaceutical sciences, especially in the area of formulation development. Tween® 80 (Polysorbate) was used as the nonionic surfactant. The nanoemulsion was prepared by using the homogenization technique, followed by its physicochemical evaluation. The surface morphological studies showed the globular structure has a nano-sized diameter, as confirmed by zeta size analysis. The zeta potential analysis confirmed a positive surface charge that might be caused by the presence of chitosan in the formulation. The pH was in the range of 5.14 to 6.11, which could also be compatible with the range of nasal pH. The viscosity of the formulations was found to be affected by the concentration of chitosan (F1-11.61 to F4-49.28). The drug release studies showed that the presence of chitosan greatly influenced the drug release, as it was noticed that formulations having an elevated concentration of chitosan release lesser amounts of the drug. The persistent stress in the mouse model caused a variety of depressive- and anxiety-like behaviors that can be counteracted by chemicals isolated from plants, such as sulforaphane and tea polyphenols. In the behavioral test and source performance test, hypericin exhibited antidepressant-like effects. The results show that the mice treated for chronic mild stress had a considerably higher preference for sucrose after receiving continuous hypericin for 4 days (p = 0.0001) compared to the animals administered with normal saline (p ≤ 0.0001) as well as the naïve group (p ≤ 0.0001). In conclusion, prepared formulations were found to be stable and can be used as a potential candidate for the treatment of depression.

In Vitro Antibacterial and Phytochemical Screening of Hypericum perforatum Extract as Potential Antimicrobial Agents against Multi-Drug-Resistant (MDR) Strains of Clinical Origin

Background

The perennial plant Hypericum perforatum is widely distributed around the world. It has been used for many years in conventional medicine to treat a variety of illnesses, including stress, mild to moderate depression, and minor injuries. This study examined the antimicrobial activity of the H. perforatum total extract and its fractions (n-hexane, ethyl acetate, chloroform, and aqueous) against multi-drug-resistant (MDR) isolates that were gathered from clinical samples, including methicillin-resistant Staphylococcus aureus (MRSA), Enterococcus faecalis, Escherichia coli, and Klebsiella pneumonia.

Materials and Methods

Aerial parts of H. perforatum were collected and extracted using various solvents and were tested versus different isolated bacterial species. The inhibition zone of tested extracts was detected using an agar diffusion assay, and MICs were measured. Phytochemical analysis of promising H. perforatum extract was done using LC-ESI-MS/MS. Ultrastructure examination for the most altered bacteria used transmission electron microscopy. Antioxidant assays were done using DPPH and ABTS scavenging capacity methods. Cytotoxicity was reported versus Vero cells.

Results

Different extracts of H. perforatum showed promising antibacterial activity against the pathogens. While the subfractions of the total extract were observed to show lesser inhibition zones and higher MIC values than the total extract of H. perforatum against MDR strains, the total extract of H. perforatum demonstrated the most potent antimicrobial action with an inhibition zone range of 17.9-27.9 mm. MDR-K. pneumoniae was discovered to be the most susceptible strain, which is consistent with the antibacterial inhibitory action of H. perforatum whole extract. Additionally, after treatment at the minimum inhibitory concentration (MIC 3.9 μg/ml), the transmission electron microscope showed alterations in the ultrastructure of the K. pneumoniae cells. Methanol extract from H. perforatum has a CC₅₀ value of 976.75 μg/ml.

Conclusion

Future inhibitors that target MDR strains may be revealed by these findings. Additionally, the extracts that were put to the test demonstrated strong antioxidant effects as shown by DPPH or ABTS radical-scavenging assays.

In vitro screening of anti-viral and virucidal effects against SARS-CoV-2 by Hypericum perforatum and Echinacea

Hypericum perforatum and Echinacea are reported to have antiviral activities against several viral infections. In this study, H. perforatum (St. John's Wort) and Echinacea were tested in vitro using Vero E6 cells for their anti-viral effects against the newly identified Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) through its infectious cycle from 0 to 48 h post infection. The hypericin of H. perforatum and the different parts (roots, seeds, aerial) of two types of Echinacea species (Echinacea purpurea and Echinacea angustifolia) were tested for their anti-viral activities to measure the inhibition of viral load using quantitative real-time polymerase chain reaction (qRT-PCR) on cell culture assay. Interestingly, the H. perforatum-Echinacea mixture (1:1 ratio) of H. perforatum and Echinacea was tested as well on SARS-CoV-2 and showed crucial anti-viral activity competing H. perforatum then Echinacea effects as anti-viral treatment. Therefore, the results H. perforatum and Echinacea species, applied in this study showed significant anti-viral and virucidal effects in the following order of potency: H. perforatum, H. perforatum-Echinacea mixture, and Echinacea on SARS-CoV-2 infectious cycle. Additionally, molecular simulation analysis of the compounds with essential proteins (Mpro and RdRp) of the SARS-CoV-2 revealed the most potent bioactive compounds such as Echinacin, Echinacoside, Cyanin, Cyanidin 3-(6''-alonylglucoside, Quercetin-3-O-glucuronide, Proanthocyanidins, Rutin, Kaempferol-3-O-rutinoside, and Quercetin-3-O-xyloside. Thus, based on the outcome of this study, it is demanding the setup of clinical trial with specific therapeutic protocol.

On the Sensitivity of the Virion Envelope to Lipid Peroxidation

Emerging viruses are a public health threat best managed with broad spectrum antivirals. Common viral structures, like capsids or virion envelopes, have been proposed as targets for broadly active antiviral drugs. For example, a number of lipoperoxidators have been proposed to preferentially affect viral infectivity by targeting metabolically inactive enveloped virions while sparing metabolically active cells. However, this presumed preferential virion sensitivity to lipoperoxidation remains untested. To test whether virions are indeed more sensitive to lipoperoxidation than are cells, we analyzed the effects of two classic generic lipoperoxidators: lipophilic 2,2'-azobis(2,4-dimethylvaleronitrile) (AMVN) and hydrophilic 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AAPH) on Vero and human foreskin fibroblasts (HFF) cell viability, HSV-1 plaquing efficiency, and virion and cell lipoperoxidation. Cells or virions were incubated with the lipoperoxidators at 37°C for 2 h or incubated in atmospheric O₂, and dose responses (half maximal cytotoxic and effective concentration [CC₅₀ and EC₅₀]) were evaluated by three or four parameter regression. The HSV-1 virions were slightly more sensitive to lipoperoxidators than were the cells (selectivity index [SI], 3.3 to 7.4). The effects of the lipophilic AMVN on both cell and virion viability directly correlated with the extent of membrane lipoperoxidation as evaluated by two different probes, C11-Bodipy and liperfluo. Moreover, the hydrophilic AAPH-induced virion inactivation at lower concentrations than did lipoperoxidation. Known lipoperoxidators inhibit infectivity via lipoperoxidation-independent mechanisms. Antioxidants protected against a loss of viral infectivity by less than 5-fold. Carrier bovine serum albumin (BSA) protected against both peroxidators to a similar extent when present together with the lipoperoxidating agents, suggesting that BSA quenches them as expected. Virions incubated in atmospheric oxidative conditions suffered losses of infectivity that were similar to those of chemically peroxidated virions, and they were protected by water soluble vitamin C and BSA with no evident lipoperoxidation, indicating predominant peroxidative damage to nonlipid virion components. Thus, lipoperoxidation is not a mechanism by which to specifically inhibit the infectivity of enveloped viruses, and the effects of known lipoperoxidators on virion infectivity are not solely mediated by lipoperoxidation. IMPORTANCE Small molecules that induce lipoperoxidation have been proposed repeatedly as potential antiviral drugs based on a presumed unique sensitivity of virions to this type of damage. Several small molecules that inactivate virions without affecting cells have been proposed to act primarily by inducing lipoperoxidation. However, the preferential sensitivity of virions to lipoperoxidators had not been experimentally evaluated. Using two of the best characterized small molecule lipoperoxidators, which are widely considered to be the prototypical water soluble and liposoluble lipoperoxidators, we show that lipoperoxidators have no preference for virions over cells. Moreover, they also inactivate virions by mechanisms other than the induction of lipoperoxidation. Therefore, the general induction of lipoperoxidation is not a path by which to develop antivirals. Moreover, molecules with specific antiviral activity which are not cytotoxic and have no preference to localize to virions over cells are unlikely to act primarily by inducing lipoperoxidation.

Hypericum Essential Oils—Composition and Bioactivities: An Update (2012–2022)

Hypericum genus, considered to comprise over 500 species that exhibit cosmopolitan distribution, has attracted human interest since ancient times. The present review aims to provide and summarize the recent literature (2012–2022) on the essential oils of the title genus. Research articles were collected from various scientific databases such as PubMed, ScienceDirect, Reaxys, and Google Scholar. Scientific reports related to the chemical composition, as well as the in vitro and in vivo pharmacological activities, are presented, also including a brief outlook of the potential relationship between traditional uses and Hypericum essential oils bioactivity.

In Silico and In Vitro Identification of Pan-Coronaviral Main Protease Inhibitors from a Large Natural Product Library

The main protease (M^pro or 3CL^pro) in coronaviruses represents a promising specific drug target as it is essential for the cleavage of the virus polypeptide and has a unique cleavage site that does not exist in human host proteases. In this study, we explored potential natural pan-coronavirus drugs using in vitro and in silico approaches and three coronavirus main proteases as treatment targets. The PyRx program was used to screen 39,442 natural-product-like compounds from the ZINC database and 121 preselected phytochemicals from medicinal plants with known antiviral activity. After assessment with Lipinski’s rule of five, molecular docking was performed for the top 33 compounds of both libraries. Enzymatic assays were applied for the top candidates from both in silico approaches to test their ability to inhibit SARS-CoV-2 M^pro. The four compounds (hypericin, rosmarinic acid, isorhamnetin, and luteolin) that most efficiently inhibited SARS-CoV-2 M^pro in vitro were further tested for their efficacy in inhibiting M^pro of SARS-CoV-1 and MERS-CoV. Microscale thermophoresis was performed to determine dissociation constant (Kd) values to validate the binding of these active compounds to recombinant M^pro proteins of SARS-CoV-2, SARS-CoV-1, and MERS-CoV. The cytotoxicity of hypericin, rosmarinic acid, isorhamnetin, and luteolin was assessed in human diploid MRC-5 lung fibroblasts using the resazurin cell viability assay to determine their therapeutic indices. Sequence alignment of M^pro of SARS-CoV-2 demonstrated 96.08%, 50.83%, 49.17%, 48.51%, 44.04%, and 41.06% similarity to M^pro of other human-pathogenic coronaviruses (SARS-CoV-1, MERS-CoV, HCoV-NL63, HCoV-OC43, HCoV-HKU1, and HCoV-229E, respectively). Molecular docking showed that 12 out of 121 compounds were bound to SARS-CoV-2 M^pro at the same binding site as the control inhibitor, GC376. Enzyme inhibition assays revealed that hypericin, rosmarinic acid, isorhamnetin, and luteolin inhibited M^pro of SARS-CoV-2, while hypericin and isorhamnetin inhibited M^pro of SARS-CoV-1; hypericin showed inhibitory effects toward M^pro of MERS-CoV. Microscale thermophoresis confirmed the binding of these compounds to M^pro with high affinity. Resazurin assays showed that rosmarinic acid and luteolin were not cytotoxic toward MRC-5 cells, whereas hypericin and isorhamnetin were slightly cytotoxic. We demonstrated that hypericin represents a potential novel pan-anti-coronaviral agent by binding to and inhibiting M^pro of several human-pathogenic coronaviruses. Moreover, isorhamnetin showed inhibitory effects toward SARS-CoV-2 and SARS-CoV-1 M^pro, indicating that this compound may have some pan-coronaviral potential. Luteolin had inhibitory effects against SARS-CoV-2 M^pro.

Small molecule interactions with the SARS-CoV-2 main protease: In silico all-atom microsecond MD simulations, PELE Monte Carlo simulations, and determination of in vitro activity inhibition

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused the ongoing COVID-19 pandemic. With some notable exceptions, safe and effective vaccines, which are now being widely distributed globally, have largely begun to stabilise the situation. However, emerging variants of concern and vaccine hesitancy are apparent obstacles to eradication. Therefore, the need for the development of potent antivirals is still of importance. In this context, the SARS-CoV-2 main protease (M^pro) is a critical target and numerous clinical trials, predominantly in the private domain, are currently in progress. Here, our aim was to extend our previous studies, with hypericin and cyanidin-3-O-glucoside, as potential inhibitors of the SARS-CoV-2 M^pro. Firstly, we performed all-atom microsecond molecular dynamics simulations, which highlight the stability of the ligands in the M^pro active site over the duration of the trajectories. We also invoked PELE Monte Carlo simulations which indicate that both hypericin and cyanidin-3-O-glucoside preferentially interact with the M^pro active site and known allosteric sites. For further validation, we performed an in vitro enzymatic activity assay that demonstrated that hypericin and cyanidin-3-O-glucoside inhibit M^pro activity in a dose-dependent manner at biologically relevant (μM) concentrations. However, both ligands are much less potent than the well-known covalent antiviral GC376, which was used as a positive control in our experiments. Nevertheless, the biologically relevant activity of hypericin and cyanidin-3-O-glucoside is encouraging. In particular, a synthetic version of hypericin has FDA orphan drug designation, which could simplify potential clinical evaluation in the context of COVID-19.

In vitro assessment of the cytotoxicity and anti-inflammatory properties of a novel dietary supplement

Studies on the immunopharmacological activities of various plant species have provided evidence for the high therapeutic potential of different extracts. These represent a promising alternative to reduce the inflammatory processes and, thus, diseases related to inflammation. Numerous scientific studies strongly suggest that diet plays an essential role in inflammation, and that certain dietary factors can act as preventive or treatment methods to lower inflammation. In the present study, a novel lingonberry-based dietary supplement was investigated for the ability to suppress the inflammatory response in activated monocytes/macrophages. Based on cell viability/proliferation and cytotoxicity tests, concentrations between 40 and 130 µg/ml of the extracts showed a high viability/proliferation effect and no cytotoxic activity in monocyte/macrophage cells. To further investigate the anti-inflammatory potential of our novel lingonberry-based dietary supplement, we studied the effect of the extract on the inflammatory response in lipopolysaccharide (LPS)-stimulated macrophages. We found that the extract exhibited a strong anti-inflammatory potential by inhibiting the expression of major inflammatory cytokines [interleukin (IL)-6, IL-8 and tumor necrosis factor (TNF)α] in activated monocyte/macrophage cells. The expression of IL-6 and IL-8 was subsequently validated by enzyme-linked immunosorbent assay (ELISA). In conclusion, we demonstrated that our product exhibits no cytotoxicity and suppresses inflammation, and thus can be considered a natural important tool for inflammation control.

Cytotoxic activities of Hypericum perforatum L. extracts against 2D and 3D cancer cell models

Six extracts were obtained from plant species Hypericum perforatum L., collected at Samsun in Turkey. The aim of this study was to examine the mechanisms of the anticancer activity of these extracts. Methanol, ethyl-acetate and hexane were used as a solvents for extraction from both branch-body part of the plant (extracts 1, 2 and 3) and from plant flowers (extracts 4, 5 and 6). The cytotoxic effects of the extracts were determined against 2D and 3D cancer cell models. Cell cycle changes of treated HeLa cells were analyzed by flow cytometry. Measurements of gene and microRNA expression levels in treated HeLa cells were done by quantitative real time PCR. Five examined extracts (2-6) exerted selective concentration-dependent cytotoxic effects on HeLa, K562, and A549 cancer cells, while the extract 1 exhibited very weak cytotoxicity. The extract 6 showed the highest intensity of cytotoxic activity. All tested extracts (2-6) demonstrated the ability to induce apoptosis in HeLa cells through activation of caspase-3. These extracts remarkably decreased gene expression levels of MMP2, MMP9, TIMP3, and VEGFA in HeLa cells. Flower extracts might have stronger effects on miR128/193a-5p/335 level changes than branch-body extracts. Hypericum perforatum extracts exerted weaker cytotoxic effects on 3D HeLa spheroids when compared with their effects on 2D monolayer HeLa cells. Taken together, results of our research may suggest the promising anticancer properties of the Hypericum perforatum extracts.

Whole-genome sequence data of Hypericum perforatum and functional characterization of melatonin biosynthesis by N-acetylserotonin O-methyltransferase

Hypericum perforatum is among the most commonly used herbal remedies and supplements. The aerial plant parts are often used to treat depression. Due to the lack of genomic information of H. perforatum, the gene networks regulating secondary metabolite synthesis remain unclear. Here, we present a high-quality genome for H. perforatum with a 2.3-Mb scaffold N50. The draft assembly covers 91.9% of the predicted genome and represents the fourth sequenced genus in the order Malpighiales. Comparing this sequence with model or related species revealed that Populus trichocarpa and Hevea brasiliensis could be grouped into one branch, while H. perforatum and Linum usitatissimum are grouped in another branch. Combined with transcriptome data, 40 key genes related to melatonin, hyperforin, and hypericin synthesis were screened and analyzed. Five N-acetylserotonin O-methyltransferases (HpASMT1-HpASMT5) were cloned and functionally characterized. Purified HpASMT3 protein converted N-acetylserotonin into melatonin with a V_max of about 1.35 pkat/mg protein. HpASMT1 and HpASMT3 overexpression in Arabidopsis mutants caused 1.5-2-fold higher melatonin content than in mutant and wild-type plants. The endogenous reactive oxygen species (ROS) in transgenic plants was significantly lower than ROS in mutant and wild-type plants, suggesting higher drought tolerance. The obtained genomic data offer new resources for further study on the evolution of Hypericaceae family, but also provide a basis for further study of melatonin biosynthetic pathways in other plants.

Pharmacologic Overview of Chlorogenic Acid and its Metabolites in Chronic Pain and Inflammation

BACKGROUND

Natural phenolic compounds in medicinal herbs and dietary plants are antioxidants which play therapeutic or preventive roles in different pathological situations, such as oxidative stress and inflammation. One of the most studied phenolic compounds in the last decade is chlorogenic acid (CGA), which is a potent antioxidant found in certain foods and drinks.

OBJECTIVE

This review focuses on the anti-inflammatory and antinociceptive bioactivities of CGA, and the putative mechanisms of action are described. Ethnopharmacological reports related to these bioactivities are also reviewed.

MATERIALS AND METHODS

An electronic literature search was conducted by authors up to October 2019. Original articles were selected.

RESULTS

CGA has been shown to reduce inflammation and modulate inflammatory and neuropathic pain in animal models.

CONCLUSION

The consensus of the literature search was that systemic CGA may facilitate pain management via bolstering antioxidant defenses against inflammatory insults.

Structure-Activity-Relationship and Mechanistic Insights for Anti-HIV Natural Products

Acquired Immunodeficiency Syndrome (AIDS), which chiefly originatesfroma retrovirus named Human Immunodeficiency Virus (HIV), has impacted about 70 million people worldwide. Even though several advances have been made in the field of antiretroviral combination therapy, HIV is still responsible for a considerable number of deaths in Africa. The current antiretroviral therapies have achieved success in providing instant HIV suppression but with countless undesirable adverse effects. Presently, the biodiversity of the plant kingdom is being explored by several researchers for the discovery of potent anti-HIV drugs with different mechanisms of action. The primary challenge is to afford a treatment that is free from any sort of risk of drug resistance and serious side effects. Hence, there is a strong demand to evaluate drugs derived from plants as well as their derivatives. Several plants, such as Andrographis paniculata, Dioscorea bulbifera, Aegle marmelos, Wistaria floribunda, Lindera chunii, Xanthoceras sorbifolia and others have displayed significant anti-HIV activity. Here, weattempt to summarize the main results, which focus on the structures of most potent plant-based natural products having anti-HIV activity along with their mechanisms of action and IC50 values, structure-activity-relationships and important key findings.

Protective effects of hypericin against infectious bronchitis virus induced apoptosis and reactive oxygen species in chicken embryo kidney cells

Avian infectious bronchitis virus (IBV), a coronavirus, causes infectious bronchitis leading to enormous economic loss in the poultry industry worldwide. Hypericin (HY) is an excellent compound that has been investigated in antiviral, antineoplastic, and antidepressant. To investigate the inhibition effect of HY on IBV infection in chicken embryo kidney (CEK) cells, 3 different experimental designs: pre-treatment of cells prior to IBV infection, direct treatment of IBV-infected cells, and pre-treatment of IBV prior to cell infection were used. Quantitative real-time PCR (qRT-PCR), immunofluorescence assay (IFA), flow cytometry, and fluorescence microscopy were performed and virus titer was determined by TCID50. The results revealed that HY had a good anti-IBV effect when HY directly treated the IBV-infected cells, and virus infectivity decreased in a dose-dependent manner. Furthermore, HY inhibited IBV-induced apoptosis in CEK cells, and significantly reduced the mRNA expression levels of Fas, FasL, JNK, Bax, Caspase 3, and Caspase 8, and significantly increased Bcl-2 mRNA expression level in CEK cells. In addition, HY treatment could decrease IBV-induced reactive oxygen species (ROS) generation in CEK cells. These results suggested that HY showed potential antiviral activities against IBV infection involving the inhibition of apoptosis and ROS generation in CEK cells.

Ethnopharmacological Applications Targeting Alcohol Abuse: Overview and Outlook

Excessive alcohol consumption is the cause of several diseases and thus is of a major concern for society. Worldwide alcohol consumption has increased by many folds over the past decades. This urgently calls for intervention and relapse counteract measures. Modern pharmacological solutions induce complete alcohol self-restraint and prevent relapse, but they have many side effects. Natural products are most promising as they cause fewer adverse effects. Here we discuss in detail the medicinal plants used in various traditional/folklore medicine systems for targeting alcohol abuse. We also comprehensively describe preclinical and clinical studies done on some of these plants along with the possible mechanisms of action.

Antiviral Activity Against Infectious Bronchitis Virus and Bioactive Components of Hypericum perforatum L

Hypericum perforatum L., also known as Saint John’s Wort, has been well studied for its chemical composition and pharmacological activity. In this study, the antiviral activities of H. perforatum on infectious bronchitis virus (IBV) were evaluated in vitro and in vivo for the first time. The results of in vitro experiments confirmed that the antiviral component of H. perforatum was ethyl acetate extraction section (HPE), and results showed that treatment with HPE significantly reduced the relative messenger ribonucleic acid (mRNA) expression and virus titer of IBV, and reduced positive green immunofluorescence signal of IBV in chicken embryo kidney (CEK) cells. HPE treatment at doses of 480–120 mg/kg for 5 days, reduced IBV induced injury in the trachea and kidney, moreover, reduced the mRNA expression level of IBV in the trachea and kidney in vivo. The mRNA expression levels of IL-6, tumor necrosis factor alpha (TNF-α), and nuclear factor kappa beta (NF-κB) significantly decreased, but melanoma differentiation-associated protein 5 (MDA5), mitochondrial antiviral signaling gene, interferon alpha (IFN-α), and interferon beta (IFN-β) mRNA levels significantly increased in vitro and in vivo. Our findings demonstrated that HPE had significant anti-IBV effects in vitro and in vivo, respectively. In addition, it is possible owing to up-regulate mRNA expression of type I interferon through the MDA5 signaling pathway and down-regulate mRNA expression of IL-6 and TNF-α via the NF-κB signaling pathway. Moreover, the mainly active compositions of HPE analyzed by high-performance liquid chromatography/electrospray ionization–mass spectroscopy (ESI-MS) are hyperoside, quercitrin, quercetin, pseudohypericin, and hypericin, and a combination of these compounds could mediate the antiviral activities. This might accelerate our understanding of the antiviral effect of H. perforatum and provide new insights into the development of effective therapeutic strategies.

Role of medicinal plants in HIV/AIDS therapy

Human immunodeficiency virus (HIV) causes the potentially life-threatening and chronic disease called acquired immune deficiency syndrome (AIDS). The main target of this viral disease is to suppress the immune system and make the body unresponsive to external stimuli. According to global health observatory data since epidemic, more than 78 million people were affected by HIV and 39 million people died globally. Until 2017, 36.5 million people were living with HIV. An estimated 0.8% (0.6%-0.9%) of adults aged 15-49 years worldwide is living with HIV. The World Health Organization (WHO) reported that the African region remains most severely affected, with nearly one in every 25 adults (4.1%) living with HIV and accounting for nearly two-thirds of the people living with HIV worldwide. WHO reported that globally only 21.7 million (19.1 million-22.6 million) people have had access to antiretroviral therapy up to 2017. Currently, antiretroviral therapy (ART) is available for the control of HIV but has serious associated side effects such as lipodystrophy. Because of the limitations, associated with ART, researchers throughout the world are trying to explore and develop more reliable and safe drugs from natural resources to manage HIV infection. A wide range of medicinal plants have been studied and have reported significant potential against HIV. Plants like Rheum palmatum L., Rheum officinale, Trigonostem axyphophylloides, Vatica astrotricha, Vernonia amygdalina, Hypoxias pelargonium, Sidoides hemerocallidea and Sutherlandia frutescens etc. have high efficacy to cure HIV. The exact mechanism of action is still not known but various phytoconstituents isolated from medicinal plants such as alkaloids, flavonoids, polyphenols, terpenoids, tannins, proteins and coumarins have the potential to interrupt the life cycle of HIV as well as act as immunomodulators to enhance the immune system of infected patients with no well reported side effects. It could be concluded that medicinal plants have potential for the management of HIV/AIDS but more studies are needed to reveal rigorous efficacy and safety concerns by conducting clinical trials at vast level to explore therapeutic impact of medicinal plants.

Reference genes for qRT-PCR normalisation in different tissues, developmental stages, and stress conditions of Hypericum perforatum

Hypericum perforatum L. is a widely known medicinal herb used mostly as a remedy for depression because it contains high levels of naphthodianthrones, phloroglucinols, alkaloids, and some other secondary metabolites. Quantitative real-time PCR (qRT-PCR) is an optimized method for the efficient and reliable quantification of gene expression studies. In general, reference genes are used in qRT-PCR analysis because of their known or suspected housekeeping roles. However, their expression level cannot be assumed to remain stable under all possible experimental conditions. Thus, the identification of high quality reference genes is essential for the interpretation of qRT-PCR data. In this study, we investigated the expression of 14 candidate genes, including nine housekeeping genes (HKGs) (ACT2, ACT3, ACT7, CYP1, EF1-α, GAPDH, TUB-α, TUB-β, and UBC2) and five potential candidate genes (GSA, PKS1, PP2A, RPL13, and SAND). Three programs-GeNorm, NormFinder, and BestKeeper-were applied to evaluate the gene expression stability across four different plant tissues, four developmental stages and a set of abiotic stress and hormonal treatments. Integrating all of the algorithms and evaluations revealed that ACT2 and TUB-β were the most stable combination in different developmental stages samples and all of the experimental samples. ACT2, TUB-β, and EF1-α were identified as the three most applicable reference genes in different tissues and stress-treated samples. The majority of the conventional HKGs performed better than the potential reference genes. The obtained results will aid in improving the credibility of the standardization and quantification of transcription levels in future expression studies on H. perforatum.

Host metabolite producing endophytic fungi isolated from Hypericum perforatum

In the present study, endophytic fungi have been isolated from various parts of the medicinal herb Hypericum perforatum (St. John’s Wort), which is known as a source of medically important metabolites. The isolated strains were cultured in liquid media and their ability to synthesize hypericin, the secondary metabolite of the host and its suspected precursor, emodin was tested analyzing the extracts of the fermentation broth and the mycelia. The HPLC-UV analysis of the chloroform/methanol extracts of the mycelia revealed that three isolates were able to produce emodin (SZMC 23771, 19.9 ng/mg; SZMC 23772, 20.8 ng/mg; SZMC 23769, 427.9 ng/mg) and one of them also could synthesize hypericin (SZMC 23769, 320.4 ng/mg). These results were also confirmed via UHPLC-HRMS technique both in full scan and MS/MS mode. The strains producing only emodin belong to the section Alternata of the genus Alternaria, while the isolate producing both metabolites was identified as Epicoccum nigrum. The mycelial extracts of E. nigrum and the Alternaria sp. SZMC 23772 showed higher inhibitory activities in the antimicrobial tests against the six selected bacteria compared to the hypericin and emodin standards in the applied concentration (100 μg/mL), while in case of the Alternaria sp. SZMC 23771 lower inhibition activities were observed on Staphylococcus aureus and Streptomyces albus than the pure compounds.

On the Mechanism of Action of Anti-Inflammatory Activity of Hypericin: An In Silico Study Pointing to the Relevance of Janus Kinases Inhibition

St. John's Wort (Hypericum perforatum L.) flowers are commonly used in ethnomedical preparations with promising outcomes to treat inflammation both per os and by topical application. However, the underlying molecular mechanisms need to be described toward a rational, evidence-based, and reproducible use. For this purpose, the aptitude of the prominent Hypericum metabolite hypericin was assessed, along with that of its main congeners, to behave as an inhibitor of janus kinase 1, a relevant enzyme in inflammatory response. It was used a molecular modeling approach relying on docking simulations, pharmacophoric modeling, and molecular dynamics to estimate the capability of molecules to interact and persist within the enzyme pocket. Our results highlighted the capability of hypericin, and some of its analogues and metabolites, to behave as ATP-competitive inhibitor providing: (i) a likely mechanistic elucidation of anti-inflammatory activity of H. perforatum extracts containing hypericin and related compounds; and (ii) a rational-based prioritization of H. perforatum components to further characterize their actual effectiveness as anti-inflammatory agents.

Effect of Hypericum humifusum aqueous and methanolic leaf extracts on biochemical and histological parameters in adult rats

Hypericum genus is traditionally known for its medicinal use and its therapeutic and antioxidant effects. However, the toxic effect of this plant has not been much explored. Our study aimed at investigating the effect of Hypericum humifusum (Hh) leaf extracts on oxidative stress parameters in male rats. For it, we first focused on the phytochemical analysis of the aqueous and methanolic extracts of Hh leaves. Hence, Wistar rats were treated per gavage for 30 days and divided into Control (1 mL/rat, distilled water), A200 group (200 mg/kg body weight (bw) aqueous extract), A400 group (400 mg/kg bw aqueous extract), M10 group (10 mg/kg bw methanolic extract), M20 group (20 mg/kg bw methanolic extract). The phytochemical analysis revealed the presence of tannins, flavonoids, steroids, carbohydrates, and phenolic compounds. Biochemical and histological investigations were performed in plasma and liver tissue. Liver tissue homogenates were used for the measurement of malondialdehyde (MDA), catalase (CAT) and superoxide dismutase (SOD) levels. At the same time, alanine transaminase (ALT), aspartate transaminase (AST) and lactate dehydrogenase (LDH) were assayed in plasma samples. Histological study was also conducted in liver. We showed that Hh extracts reduced relative liver weight and increased ALT, AST, LDH activities in treated groups compared to control group. These results were associated with an increase of MDA levels and a decrease of antioxidant enzyme activities (CAT and SOD) in liver tissues of treated rats. Histology of liver demonstrated several alterations showing necrosis, altered hepatocytes and lymphocyte migration mainly in A200 group and dilated sinusoids, foamy appearance of hepatocytes and lymphocyte accumulation in the other treated groups. This original work indicated that chronic consumption of Hh leaf extracts has no antioxidant effect but instead it induces oxidative stress and enhances markers of cell damage which was confirmed by histological study of liver rats.

Medicinal Plants Used in the Treatment of Human Immunodeficiency Virus

Since the beginning of the epidemic, human immunodeficiency virus (HIV) has infected around 70 million people worldwide, most of whom reside is sub-Saharan Africa. There have been very promising developments in the treatment of HIV with anti-retroviral drug cocktails. However, drug resistance to anti-HIV drugs is emerging, and many people infected with HIV have adverse reactions or do not have ready access to currently available HIV chemotherapies. Thus, there is a need to discover new anti-HIV agents to supplement our current arsenal of anti-HIV drugs and to provide therapeutic options for populations with limited resources or access to currently efficacious chemotherapies. Plant-derived natural products continue to serve as a reservoir for the discovery of new medicines, including anti-HIV agents. This review presents a survey of plants that have shown anti-HIV activity, both in vitro and in vivo.

Prenylated phloroglucinols from Hypericum scruglii, an endemic species of Sardinia (Italy), as new dual HIV-1 inhibitors effective on HIV-1 replication

In a search for new potential multitarget anti-HIV compounds from natural products, we have identified in Hypericum scruglii, an endemic and exclusive species of Sardinia (Italy), a potent plant lead. The phytochemical study of the hydroalcoholic extract obtained from its leaves led to the isolation of its most abundant secondary metabolites, belonging to different chemical classes. In particular, three phloroglucinols derivatives were identified, confirming their significance as chemotaxonomic markers of the Hypericum genus. Among them, the 3-(13-hydroxygeranyl)-1-(2'-methylbutanoyl)phloroglucinol was reported here for the first time. All six isolated compounds have been evaluated firstly for the inhibition of both Human Immunodeficiency Virus type 1 (HIV-1) Reverse Transcriptase (RT)-associated DNA Polymerase (RDDP) and Ribonuclease H (RNase H) activities, for the inhibition of HIV-1 integrase (IN) in biochemical assays, and also for their effect on viral replication. Among the isolated metabolites, three phloroglucinol derivatives and quercitrin were effective on both RT-associated RDDP and RNase H activities in biochemical assays. The same active compounds affected also HIV-1 IN strand transfer function, suggesting the involvement of the RNase H active site. Furthermore, phloroglucinols compounds, included the newly identified compound, were able to inhibit the HIV-1 replication in cell based assays.

Effects of Hypericum perforatum extract on oxaliplatin-induced neurotoxicity: in vitro evaluations

Hypericum perforatum L. has been used for centuries as a natural remedy for the treatment of many disorders. Neuropathic pain is a common side effect of oxaliplatin-based chemotherapy and often the cause of therapy discontinuation. Thanks to its anti-inflammatory and analgesic effects, the use of H. perforatum may be a novel therapeutic strategy for neuropathy. The aim of this paper was to evaluate the effect of H. perforatum hydrophilic extract on an in vitro model of oxaliplatin-induced neurotoxicity. The antioxidant potential of extract was first evaluated in cell-free models by the thiobarbituric acid-reactive substances assay and nitro blue tetrazolium oxidation test; the ability of H. perforatum extract to reduce oxaliplatin-induced caspase-3 activity in rat astrocytes and its potential interference with the cytotoxic effects of oxaliplatin in a colorectal cancer in vitro model (HT-29 cells) were also evaluated. The extract showed a significant antioxidant effect and was able to reduce caspase-3 activity in rat astrocytes. Of note, the extract alone exerted a cytotoxic effect in HT-29 cells and did not reduce the cytotoxicity of oxaliplatin in HT-29 cells. These data suggest that H. perforatum could be used as a novel therapeutic strategy for counteracting chemotherapy-induced neuropathy.

Metabolomic Profiling, Antioxidant and Anti-inflammatory Activities of Hypericum Species Growing in South Korea

Although Hypericum species are best known as plants that produce hypericin and are used in folk medicine, their other chemical constituents are poorly understood. Polyphenolic secondary metabolites from whole plants of representative Korean Hypericum species ( H. laxum Koidz., H. erectum Thunb., and H. ascyron L.) were analyzed using a ultra performance liquid chromatography-quadrupole time-of-flight/mass spectrometry (UPLC-Q-TOF/MS)-based approach combined with unsupervised principal component analysis (PCA) multivariate analysis. On the loading scatter plot, significant changes in metabolites were found between species, and three flavonol glycosides (8: quercetin-3- O-galactoside, 12: kaempferol-3- O-glucoside, and 13: quercetin-3- O-rhamnoside) were evaluated as key markers among 17 isolated metabolites. The extracts of H. laxum Koidz. exhibited significant quenching effects on DPPH and ABTS radicals, with IC50 values of 10–20 μg/mL, and were slightly higher in total phenol (TP) and total flavonoid (TF) contents than other species. Additionally, anti-inflammatory activity was observed by reduced nitric oxide (NO) and interleukin-6 (IL-6) production from lipopolysaccharide (LPS)-stimulated macrophages (RAW 264.7 cells). This is the first study to report the presence of bioactive metabolites and their correlating biological activities in H. laxum Koidz.

Hypericum perforatum (St John's wort) beyond depression: A therapeutic perspective for pain conditions

ETHNOPHARMACOLOGICAL RELEVANCE

Hypericum perforatum L. (Hypericaceae), popularly called St. John's wort (SJW), has a rich historical background being one of the oldest used and most extensively investigated medicinal herbs. Many bioactivities and applications of SJW are listed in popular and in scientific literature, including antibacterial, antiviral, anti-inflammatory. In the last three decades many studies focused on the antidepressant activity of SJW extracts. However, several studies in recent years also described the antinociceptive and analgesic properties of SJW that validate the traditional uses of the plant in pain conditions.

AIM OF THE REVIEW

This review provides up-to-date information on the traditional uses, pre-clinical and clinical evidence on the pain relieving activity of SJW and its active ingredients, and focuses on the possible exploitation of this plant for the management of pain.

MATERIALS AND METHODS

Historical ethnobotanical publications from 1597 were reviewed for finding local and traditional uses. The relevant data on the preclinical and clinical effects of SJW were searched using various databases such as PubMed, Science Direct, Scopus, and Google Scholar. Plant taxonomy was validated by the database Plantlist.org.

RESULTS

Preclinical animal studies demonstrated the ability of low doses of SJW dry extracts (0.3% hypericins; 3-5% hyperforins) to induce antinociception, to relieve from acute and chronic hyperalgesic states and to augment opioid analgesia. Clinical studies (homeopathic remedies, dry extracts) highlighted dental pain conditions as a promising SJW application. In vivo and in vitro studies showed that the main components responsible for the pain relieving activity are hyperforin and hypericin. SJW analgesia appears at low doses (5-100mg/kg), minimizing the risk of herbal-drug interactions produced by hyperforin, a potent inducer of CYP enzymes.

CONCLUSION

Preclinical studies indicate a potential use of SJW in medical pain management. However, clinical research in this field is still scarce and the few studies available on chronic pain produced negative results. Prospective randomized controlled clinical trials performed at low doses are needed to validate its potential efficacy in humans.

Antinociceptive Properties of St. John's Wort (Hypericum perforatum) and Other Hypericum Species

This review aims at a coherent summary of the results obtained from various studies that concern analgesic-like activity of the extracts of H. preforatum L. and thirteen other Hypericum L. species (Hypericaceae). Botanical origin, plant organs and extraction modes of the plant material, experimental models, routes of administration and doses used for animal treatment are summarized. Mechanisms of action and substances (and even the synergy thereof) proposed so far to be responsible for the observed activity have also been discussed. Even though St. John's wort ( H. perforatum) is the most renowned plant species of this genus, it is neither the only nor the most potent one in inducing pain relief.

Comparative Transcriptome Reconstruction of Four Hypericum Species Focused on Hypericin Biosynthesis

Next generation sequencing technology rapidly developed research applications in the field of plant functional genomics. Several Hypericum spp. with an aim to generate and enhance gene annotations especially for genes coding the enzymes supposedly included in biosynthesis of valuable bioactive compounds were analyzed. The first de novo transcriptome profiling of Hypericum annulatum Moris, H. tomentosum L., H. kalmianum L., and H. androsaemum L. leaves cultivated in vitro was accomplished. All four species with only limited genomic information were selected on the basis of differences in ability to synthesize hypericins and presence of dark nodules accumulating these metabolites with purpose to enrich genomic background of Hypericum spp. H. annulatum was chosen because of high number of the dark nodules and high content of hypericin. H. tomentosum leaves are typical for the presence of only 1-2 dark nodules localized in the apical part. Both H. kalmianum and H. androsaemum lack hypericin and have no dark nodules. Four separated datasets of the pair-end reads were gathered and used for de novo assembly by Trinity program. Assembled transcriptomes were annotated to the public databases Swiss-Prot and non-redundant protein database (NCBI-nr). Gene ontology analysis was performed. Differences of expression levels in the marginal tissues with dark nodules and inner part of leaves lacking these nodules indicate a potential genetic background for hypericin formation as the presumed site of hypericin biosynthesis is in the cells adjacent to these structures. Altogether 165 contigs in H. annulatum and 100 contigs in H. tomentosum were detected as significantly differentially expressed (P < 0.05) and upregulated in the leaf rim tissues containing the dark nodules. The new sequences homologous to octaketide synthase and enzymes catalyzing phenolic oxidative coupling reactions indispensable for hypericin biosynthesis were discovered. The presented transcriptomic sequence data will improve current knowledge about the selected Hypericum spp. with proposed relation to hypericin biosynthesis and will provide a useful resource of genomic information for consequential studies in the field of functional genomics, proteomics and metabolomics.

Immunomudulatory effects of hydroalcoholic extract of Hypericum perforatum

OBJECTIVE

Hypericum perforatum (St. John's Wort) has long been used in traditional medicine to treat a variety of internal and external ailments. The present study was done to evaluate the immumodulatory potentials of the hydroalcoholic extract of H. perforatum.

MATERIALS AND METHODS

Twenty male BALB/c-mice were randomly allocated in two equal groups and immunized with sheep red blood cells (SRBCs) and complete Freund's adjuvant. Mice in the treatment group orally received hydroalcoholic extract of H. perforatum (110 mg/Kg daily) from the beginning of the study which continued for 2 weeks.

RESULTS

The data indicated a significant increase in the level of anti-SRBC antibody and simultaneously a significant decrease in the level of cellular immunity, an enhancement in foot pad thickness, in treatment group compared to control group. The level of the respiratory burst in phagocytic cells and the level of lymphocyte proliferation in splenocytes were significantly decreased in the treatment group compared to control group. Moreover, extract caused a significant reduction in the production of pro-inflammatory IL-17 as well as IFN-γ, parallel to increasing the level of IL-6.

CONCLUSIONS

The hydroalcoholic extract of H. perforatum may be used as a natural source for treatment of immunopathologic conditions.

Reference genes selection and normalization of oxidative stress responsive genes upon different temperature stress conditions in Hypericum perforatum L

Reverse transcription-quantitative real-time PCR (RT-qPCR) is a widely used technique for gene expression analysis. The reliability of this method depends largely on the suitable selection of stable reference genes for accurate data normalization. Hypericum perforatum L. (St. John's wort) is a field growing plant that is frequently exposed to a variety of adverse environmental stresses that can negatively affect its productivity. This widely known medicinal plant with broad pharmacological properties (anti-depressant, anti-tumor, anti-inflammatory, antiviral, antioxidant, anti-cancer, and antibacterial) has been overlooked with respect to the identification of reference genes suitable for RT-qPCR data normalization. In this study, 11 candidate reference genes were analyzed in H. perforatum plants subjected to cold and heat stresses. The expression stability of these genes was assessed using GeNorm, NormFinder and BestKeeper algorithms. The results revealed that the ranking of stability among the three algorithms showed only minor differences within each treatment. The best-ranked reference genes differed between cold- and heat-treated samples; nevertheless, TUB was the most stable gene in both experimental conditions. GSA and GAPDH were found to be reliable reference genes in cold-treated samples, while GAPDH showed low expression stability in heat-treated samples. 26SrRNA and H2A had the highest stabilities in the heat assay, whereas H2A was less stable in the cold assay. Finally, AOX1, AOX2, CAT1 and CHS genes, associated with plant stress responses and oxidative stress, were used as target genes to validate the reliability of identified reference genes. These target genes showed differential expression profiles over time in treated samples. This study not only is the first systematic analysis for the selection of suitable reference genes for RT-qPCR studies in H. perforatum subjected to temperature stress conditions, but may also provide valuable information about the roles of genes associated with temperature stress responses.

Hypericins: biotechnological production from cell and organ cultures

Hypericum perforatum L. (St. John's wort), a perennial flowering plant native to Europe, is widely used as a medicinal plant and has a long history of its use in the treatment of various ailments. Currently, H. perforatum is widely used as an herbal remedy for the treatment of mild to moderate depression. Hypericins are natural napthodianthrone compounds produced from H. perforatum (St. John's wort) which are having antitumor, antiviral (i.e., against human immunodeficiency and hepatitis C virus), antineoplastic, and antidepressant properties. Currently, field-grown plant materials are generally used for the commercial production of hypericins. It has been reported that hypericin accumulation in natural plants is influenced by different ecological and environmental conditions including light intensity, nitrogen availability, temperature, seasons, and growing regions. Therefore, up to 17-fold and 13-fold differences in hypericin and pseudohypericin amounts, respectively, are reported in different phytopharmaceutical preparations. Plant cell and organ cultures are effective systems for producing natural products, and attempts were made for the production of biomass and stable concentrations of hypericins through in vitro cultures of H. perforatum. Cell, callus, shoot, plantlet, and adventitious root cultures have been established and various chemical and physical factors which influence the biomass and secondary metabolite accumulation have been investigated. Large-scale plantlet and adventitious root cultures have also been attempted in H. perforatum in bioreactors, and various strategies have been applied for the production of higher biomass and secondary products. This review describes the biotechnological approaches employed for the production of hypericins and focuses upon the challenges and future prospects.

The immuno-regulatory impact of orally-administered Hypericum perforatum extract on Balb/C mice inoculated with H1n1 influenza A virus

Hypericumperforatum (H. perforatum) ethanol extract has been found to inhibit lipopolysaccharide-induced production of inflammatory mediators and cytokines in cultured macrophages. Therefore, it may be able to protect the host from excessive inflammation during viral infection. In the current study, the immune-regulatory effect of H. perforatum extract was evaluated in A549 lung epithelial cells and BALB/c mice exposed to Influenza A/PR/8/34 H1N1 virus. In A549 cells, the extract (30 µg/mL) significantly inhibited influenza virus induced monocyte chemotactic protein (MCP)-1 and interferon-γ induced protein 10 kD (IP-10), but dramatically increased interleukin-6 (IL-6). In mice inoculated intranasally with 10^7.9 EID₅₀ of Influenza A/PR/8/34 H1N1 (high dose), daily oral treatment of H. perforatum extract at a rate of 110 mg/kg of body weight increased lung viral titer, bronchoalveolar lavage (BAL) pro-inflammatory cytokine and chemokine levels, and the infiltration of pro-inflammatory cells in the lung 5 days post-inoculation, as compared to ethanol vehicle treated mice. Transcription of suppressor of cytokine signaling 3 (SOCS3) was increased by H. perforatum extract both in A549 cells and BALB/c mice, which could have interrupted anti-viral immune response and thus led to the inefficient viral clearance and increased lung inflammation. H. perforatum treatment resulted in minor reduction in viral titer without affecting body weight when mice were inoculated with a lower dose (~10^5.0 EID₅₀) and H. perforatum was applied in the later phase of infection. Mice challenged intranasally with high dose of influenza virus (10^7.9 EID₅₀) suffered from a higher mortality rate when dosed with H. perforatum extract. In conclusion, the current study showed that SOCS3 elevation by H. perforatum may cause impaired immune defense against influenza virus infection and lead to higher mortality.

St. John's wort reversal of meningeal nociception: a natural therapeutic perspective for migraine pain

Despite a number of antimigraine drugs belonging to different pharmacological classes are available, there is a huge unmet need for better migraine pharmacotherapy. We here demonstrated the capability of Hypericum perforatum, popularly called St. John's wort (SJW), to relieve meningeal nociception in an animal model induced by administration of the nitric oxide (NO) donors glyceryl trinitrate (GTN) and sodium nitroprusside (SNP). GTN and SNP produced a delayed meningeal inflammation, as showed by the upregulation of interleukin (IL)-1β and inducible NO synthase (iNOS), and a prolonged cold allodynia and heat hyperalgesia with a time-course consistent with NO-induced migraine attacks. A single oral administration of a SJW dried extract (5mg/kg p.o.) counteracted the nociceptive behaviour and the overexpression of IL-1β and iNOS. To clarify the cellular pathways involved, the expression of protein kinase C (PKC) and downstream effectors was detected. NO donors increased expression and phosphorylation of PKCγ, PKCɛ and transcription factors, such as nuclear factor (NF)-κB, cyclic AMP response element binding protein (CREB), Signal Transducer and Activator of Transcription (STAT)-1. All these molecular events were prevented by SJW and hypericin, a SJW main component. In conclusion, SJW counteracted the NO donor-induced pain hypersensitivity and meningeal activation by blocking PKC-mediated pathways involving NF-κB, CREB, STAT1. These results might suggest SJW as an innovative and safe perspective for migraine pain.

Identification and biosynthesis of acylphloroglucinols in Hypericum gentianoides

Species of the genus Hypericum contain a rich array of unusual polyketides, however, only a small proportion of the over 450 Hypericum species, other than the popular medicinal supplement St. John's Wort (Hypericum perforatum), have even been chemically characterized. Hypericum gentianoides, a small annual used medicinally by Cherokee Americans, contains bioactive acylphloroglucinols. Here, we identify acylphloroglucinol constituents of H. gentianoides and determine a potential pathway to their synthesis. Liquid chromatography/electrospray ionization-mass spectrometry (LC/ESI-MS) and HPLC-UV indicate that the level of accumulation and profile of acylphloroglucinols in H. gentianoides vary little seasonally when grown in a greenhouse, but do vary with development and are highly dependent on the accession, highlighting the importance of the selection of plant material for study. We identify the chemical structures of the nine prevalent polyketides, based on LC/ESI-MS and hybrid quadrupole orthogonal time-of-flight (Q-TOF) mass spectrometry; these metabolites include one monomeric phlorisobutyrophenone (PIB) derivative and eight dimeric acylphloroglucinols. Q-TOF spectrometry was used to identify eight additional PIB derivatives that were not detected by LC/ESI-MS. These data lead us to propose that diacylphloroglucinols are synthesized via modification of PIB to yield diverse phloroglucinol and filicinic acids moieties, followed by dimerization of a phloroglucinol and a filicinic acid monomer to yield the observed complement of diacylphloroglucinols. The metabolomics data from H. gentianoides are accessible in plant metabolomics resource (PMR) (http://www.metnetdb.org/pmr), a public metabolomics database with analysis software for plants and microbial organisms.

Benzophenone glycosides from Hypericum humifusum ssp. austral

Six new benzophenone glycosides, 2,3',4,5',6-pentahydroxybenzophenone 4-O-(6″-benzoyl)-β-d-glucopyranoside (1), 2,3',4,5',6-pentahydroxybenzophenone 4-O-β-d-glucopyranoside (2), 2,3',4,5',6-pentahydroxybenzophenone 2-O-(2″-benzoyl)-α-l-arabinopyranoside (3), 2,3',4,5',6-pentahydroxybenzophenone 2-O-α-l-arabinopyranoside (4), 2,3',4,5',6-pentahydroxybenzophenone 2-O-(4″-acetyl)-β-d-xylopyranoside (5), and 2,3',4,5',6-pentahydroxybenzophenone 3-C-(4″-benzoyl)-β-d-glucopyranoside (6), and five known compounds were isolated from the aerial parts of Hypericum humifusum ssp. austral. The structures of 1-6 were elucidated by mass spectrometry and extensive 1D and 2D NMR spectroscopy.

Reversal of NO-induced nociceptive hypersensitivity by St. John's wort and hypericin: NF-κB, CREB and STAT1 as molecular targets

RATIONALE

Hypericum perforatum, popularly called St. John's wort (SJW), is a medicinal plant mainly used as antidepressant with a favorable safety profile than standard antidepressants. Some studies have also documented other SJW bioactivities, including pain modulation.

OBJECTIVES

The aim of this study was to demonstrate the capability of SJW to relieve nitric oxide (NO)-induced nociceptive hypersensitivity and identify the effective component.

METHODS

Nociceptive hypersensitivity induced by administration of the NO donors nitroglycerin (GTN) and sodium nitroprusside (SNP) was assessed by cold and hot plate tests. The cellular pathways and molecular targets involved were investigated by Western blotting.

RESULTS

GTN and SNP produced a prolonged allodynia and hyperalgesia in mice. A single oral administration of low doses of an SJW dried extract or purified hypericin reversed the NO donor-induced nociceptive behavior whereas hyperforin and flavoinoids were ineffective. Investigating into the cellular pathways involved, an increased CREB and STAT1 phosphorylation, and activation of NF-κB were detected within PAG and thalamus following NO donors' administration. These cellular events were prevented by SJW or hypericin. Since hypericin showed PKC blocking properties, a role of PKC as an upstream modulator of these transcription factors was hypothesized. NO donors increased expression and phosphorylation of protein kinase C (PKC) γ and ε isoforms, molecular events prevented by SJW or hypericin.

CONCLUSIONS

SJW reversed NO-induced nociceptive hypersensitivity through the blockade of a supraspinal signaling pathway involving a PKC-dependent CREB, STAT1 and NF-κB activation due to presence of hypericin. These data indicate SJW/hypericin as a therapeutic perspective for pain treatment.

A systematic review and meta-analysis on the use of Hypericum perforatum (St. John's Wort) for pain conditions in dental practice

BACKGROUND

Hypericum perforatum (St. John's Wort) has been used for a variety of medicinal indications. Most recent research has focussed on its use in herbal form for depression, but its claimed analgesic and anti-inflammatory properties in homeopathic form have also led to a number of studies in patients with acute pain conditions. This systematic review overviews the literature on the use of St. John's Wort for pain conditions in homeopathic dental practice.

MATERIAL AND METHODS

PubMed, EMBASE, AMED, CAMbase and the electronic archives of Thieme Publishers were searched with the search terms "(Hypericum OR St. Johns Wort) AND pain". We reviewed and meta-analysed the evidence on Hypericum in pain after tooth extraction was carried out.

RESULTS

Twenty one relevant articles were found: four described general recommendations, three basic research, six reported studies in dental care and eight were expert opinions or case reports. Four studies were eligible for the meta-analysis. There was marked high heterogeneity in the effects pain (Chi-Squared = 26.46; I(2) = 0.89). The overall effect of 0.24 (95% CI: [0.06; 1.03]) favours Hypericum but is not statistically significant.

CONCLUSION

Although case reports suggest therapeutic potential of Hypericum for pain conditions in dental care, this effect is not currently supported by clinical studies. All studies included in this meta-analysis used Arnica montana as well as Hypericum the results are more influenced by Arnica than Hypericum. Further clinical controlled trials of Hypericum alone in dental practice should be performed.

Chemical composition and larvicidal activity of several essential oils from Hypericum species from Tunisia

The chemical composition of the essential oils extracted from some Tunisian Hypericum species and their larvicidal activity against Culex pipiens larvae were evaluated. The chemical compositions of the essential oils from the aerial plant parts were analyzed using gas chromatography-mass spectrometry. One hundred and thirty-four compounds were identified, ranging between 85.1 and 95.4 % of the oil's composition. The components were monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene hydrocarbons, oxygenated sesquiterpenes, non-terpenic hydrocarbons, and others. The larvicidal activity of the essential oils was evaluated using a method recommended by WHO. Larvicidal tests revealed that essential oils from the Hypericum species have a significant larvicidal activity against C. pipiens, with LC(50) ranging between 102.82 and 194.70 ppm. The most powerful essential oils against these larvae were Hypericum tomentosum and Hypericum humifusum samples, followed by the essential oil of Hypericum perforatum.