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570 result(s) for "Hypericum perforatum"
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St. John’s Wort (Hypericum perforatum) Products – How Variable Is the Primary Material?
Saint John's wort ( L., HP) is commonly registered in Europe under the THR scheme (Traditional Herbal Registration) or licensed as a medicine. Nonetheless unregulated medical products and food supplements are accessible through the internet which are often of poor quality. The species' natural distribution stretches through large regions of Europe to China and four subspecies have been distinguished. When compared to the European Pharmacopoeia reference, the presence of additional compounds was linked to so-called Chinese HP. In order to obtain an integrated picture of the entire chemoprofile, the chemical composition of HP was studied using a combination of techniques well-established in the relevant industries. The impact of phytogeographic factors on the can shed light on whether the variability of the final products is strongly influenced by these factors of whether they relate to poor processing, adulteration, or other factors linked to the processing of the material. Eighty-six samples (77 . ) were collected from 14 countries. Most were authenticated and harvested in the wild; others came as roughly ground material from commercial cultivations, markets and pharmacies. The samples were analyzed using HPTLC and H-NMR-based principal component analysis (PCA). Limited chemical variability was found. Nonetheless, the typical fingerprint of Chinese HP was observed in each specimen from China. Additional compounds were also detected in some samples collected in Spain. Rutin is not necessarily present in the crude material. The variability previously found in the marketed products can be ascribed only partially to the geographical origin of harvested material, but mainly to the plant part harvested, closely related to harvesting techniques, processing and probably time of harvest. HP can be sourced in a consistent composition (and thus quality) from different geographical sources. However, chemical variability needs to be accounted for when evaluating what is considered authentic good material. Therefore, the processing and good practice are all stages of primary importance, calling for a better (self-)regulation and quality assurance along the value chain of an herbal medical product or botanical.
Microbe-mediated local adaptation to limestone barrens is context dependent
Plant-root-associated microbes influence plant phenotype and tolerance to environmental stress, and thus have been hypothesized to play a role in plant local adaptation. Here, we test this hypothesis with factorial experiments addressing the role of microbes in local adaptation of Hypericum perforatum (St. John’s wort) to stressful limestone barrens (alvars) compared to neighboring old-fields. Alvar plants benefited more from microbes in early life history stages, while at later growth stages, alvar and old-field plants benefited equally from microbes but only in the old-field habitat. Patterns of local adaptation were changed by the presence of microbes. Alvar plants grown in association with alvar microbes outperformed old-field plants in the alvar habitat, whereas old-field plants showed patterns of maladaptation when grown with microbes. In this demonstration of microbe-mediated adaptation, we show that rhizosphere microbes can be important for plant fitness and patterns of local adaptation but that those effects are dependent on life-history stage and habitat.
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.
Immobilization of α-Amylase onto Quantum Dots Prepared from Hypericum perforatum L. Flowers and Hypericum capitatum Seeds: Its Physicochemical and Biochemical Characterization
Enzyme immobilization is an effective way to increase the catalytic activity and stability of the α-amylase (Amy) enzyme for industrial uses. For this purpose, carbon and graphene quantum dot (QDs) structures were prepared from Hypericum perforatum L. flowers (QD-1), and Hypericum capitatum seeds (QD-2) obtained from an herbalist in Hatay province of Turkey. Structural and morphological characterization of the prepared QDs and QDs/Amy were carried out by Fourier transform infrared spectrophotometer (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), and energy dispersive X-ray (EDX). Meanwhile, biochemical characterizations such as optimum pH and temperature, kinetic parameters, effects of metal ions, organic solvents, and trypsin digestion on enzyme activity were performed and compared with free Amy. The Amy enzyme was immobilized with an activity efficiency of 71.15% for QD-1/Amy, and 81.51% for QD-2/Amy under optimal conditions. The difference in activity efficiency between QD-1/Amy and QD-2/Amy was likely due to a change in the surface porosity of QDs structures. While the optimal pH value of all three forms of Amy was recorded as 6.0, their optimal temperature was found to be 40 °C. The activation energy (E a ) of the free Amy was found to be 4.81 kJ/mol, while it was 9.61 kJ/mol, and 3.20 kJ/mol for QD-1/Amy, and QD-2/Amy, respectively. K m values were calculated as 1.18, 1.57, and 1.35 mg/mL for free Amy, QD-1/Amy, and QD-2/Amy, respectively, and V max values were calculated as 37.52, 37.60, and 39.93 µmol/min, respectively. Kinetic data revealed that the immobilized enzymes had lower substrate affinity compared to the free Amy. Besides, the QD-1/Amy and QD-2/Amy exhibited more stability than free Amy against metal ions, organic solvents as well as trypsin digestion due to the increment in conformational rigidity caused by changes in the secondary structures of the immobilized enzyme. For instance, after incubation with trypsin for 120 min, free Amy, QD-1/Amy, and QD-2/Amy retained approximately 20%, 35%, and 26% of initial activities, respectively. Finally, it can be proposed that the prepared carriers in this work may a useful to produce stable and active immobilized Amy to be used in industrial applications.
Development of Controlled Delivery Functional Systems by Microencapsulation of Different Extracts of Plants: Hypericum perforatum L., Salvia officinalis L. and Syzygium aromaticum
Extracts of different plants ( Hypericum perforatum L., Salvia officinalais L . and Syzygium aromaticum ) were microencapsulated. Different microparticles were prepared by a spray drying process, and they were fully characterized and evaluated in terms of controlled release. The product yield of the spray dryer varied from 26.5 to 65.5 wt%. All the microparticles present a regular shape, a very smooth surface and a mean size smaller than 20 μm. The total release was achieved in less than 70 min. The encapsulation efficiency was around 100%. The release profiles were simulated and evaluated using different kinetic models: Korsmeyer-Peppas (R 2 : 0.795–0.992), Weibull (R 2 : 0.973–0.999) and Baker–Lonsdale (R 2 : 0.855–0.964). These mathematical models allowed the evaluation of the mass transport mechanisms involved in the release, which, in turn, helps to design a system with specific characteristics. Finally, the Weibull model presents a better adjustment to the experimental release profiles, and the drug transport mechanism involved in almost all the release profiles studied is by an anomalous transport.
Hypericum perforatum L. Regulates Glutathione Redox Stress and Normalizes Ggt1/Anpep Signaling to Alleviate OVX-Induced Kidney Dysfunction
Menopause and associated renal complications are linked to systemic redox stress, and the causal factors remain unclear. As the role of Hypericum perforatum L. (HPL) in menopause-induced kidney disease therapy is still ambiguous, we aim to explore the effects of HPL on systemic redox stress under ovariectomy (OVX)-induced kidney dysfunction conditions. Here, using combined proteomic and metabolomic approaches, we constructed a multi-scaled “HPL-disease-gene-metabolite” network to generate a therapeutic “big picture” that indicated an important link between glutathione redox stress and kidney impairment. HPL exhibited the potential to maintain cellular redox homeostasis by inhibiting gamma-glutamyltransferase 1 (Ggt1) overexpression, along with promoting the efflux of accumulated toxic amino acids and their metabolites. Moreover, HPL restored alanyl-aminopeptidase (Anpep) expression and metabolite shifts, promoting antioxidative metabolite processing, and recovery. These findings provide a comprehensive description of OVX-induced glutathione redox stress at multiple levels and support HPL therapy as an effective modulator in renal tissues to locally influence the glutathione metabolism pathway and subsequent redox homeostasis.
Spatial chemo-profiling of hypericin and related phytochemicals in Hypericum species using MALDI-HRMS imaging
Advanced analytical imaging techniques, including matrix-assisted laser desorption/ionization high-resolution mass spectrometry (MALDI-HRMS) imaging, can be used to visualize the distribution, localization, and dynamics of target compounds and their precursors with limited sample preparation. Herein we report an application of MALDI-HRMS imaging to map, in high spatial resolution, the accumulation of the medicinally important naphthodianthrone hypericin, its structural analogues and proposed precursors, and other crucial phytochemical constituents in the leaves of two hypericin-containing species, Hypericum perforatum and Hypericum olympicum . We also investigated Hypericum patulum , which does not contain hypericin or its protoforms. We focused on both the secretory (dark glands, translucent glands, secretory canals, laminar glands, and ventral glands) and the surrounding non-secretory tissues to clarify the site of biosynthesis and localization of hypericin, its possible precursors, and patterns of localization of other related compounds concomitant to the presence or absence of hypericin. Hypericin, pseudohypericin, and protohypericin accumulate in the dark glands. However, the precursor emodin not only accumulates in the dark glands but is also present outside the glands in both hypericin-containing species. In hypericin-lacking H. patulum , however, emodin typically accumulates only in the glands, thereby providing evidence that hypericin is possibly biosynthesized outside the dark glands and thereafter stored in them. The distribution and localization of related compounds were also evaluated and are discussed concomitant to the occurrence of hypericin. Our study provides the basis for further detailed investigation of hypericin biosynthesis by gene discovery and expression studies.
Ovule Gene Expression Analysis in Sexual and Aposporous Apomictic Hypericum perforatum L. (Hypericaceae) Accessions
L. (2 = 4 = 32) is an attractive model system for the study of aposporous apomixis. The earliest phenotypic features of aposporous apomixis in this species are the mitotic formation of unreduced embryo sacs from a somatic cell of the ovule nucellus and the avoidance of meiosis. In this research we addressed gene expression variation in sexual and apomictic plants, by focusing on the ovule nucellus, which is the cellular domain primarily involved into the differentiation of meiocyte precursors and aposporous embryo sacs, at a pre-meiotic developmental stage. Gene expression analyses performed by RNAseq identified 396 differentially expressed genes and 1834 transcripts displaying phenotype-specific expression. Furthermore, the sequencing and assembly of the genome from a diploid sexual accession allowed the annotation of a 50 kb sequence portion located upstream the HAPPY locus and to address the extent to which single transcripts were assembled in multiple variants and their co-expression levels. About one third of identified DEGs and phenotype-specific transcripts were associated to transcript variants with alternative expression patterns. Additionally, considering DEGs and phenotype-specific transcript, the co-expression level was estimated in about two transcripts per locus. Our gene expression study shows massive differences in the expression of several genes encoding for transposable elements. Transcriptional differences in the ovule nucellus and pistil terminal developmental stages were also found for subset of genes encoding for potentially interacting proteins involved in pre-mRNA splicing. Furthermore, the sexual and aposporous ovule transcriptomes were characterized by differential expression in genes operating in RNA silencing, RNA-mediated DNA methylation (RdDM) and histone and chromatin modifications. These findings are consistent with a role of these processes in regulating cell fate determination in the ovule, as indicated by forward genetic studies in sexual model species. The association between aposporous apomixis, pre-mRNA splicing and DNA methylation mediated by sRNAs, which is supported by expression data and by the enrichment in GO terms related to these processes, is consistent with the massive differential expression of multiple transposon-related sequences observed in ovules collected from both sexual and aposporous apomictic accessions. Overall, our data suggest that phenotypic expression of aposporous apomixis is concomitant with the modulation of key genes involved in the two interconnected processes: RNA splicing and RNA-directed DNA methylation.
Reference Genes Selection and Normalization of Oxidative Stress Responsive Genes upon Different Temperature Stress Conditions in Hypericum perforatum L
Abstract 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.
Hypericum perforatum L. Nanoemulsion Mitigates Cisplatin-Induced Chemobrain via Reducing Neurobehavioral Alterations, Oxidative Stress, Neuroinflammation, and Apoptosis in Adult Rats
Cisplatin (Cis) is a potent chemotherapeutic agent; however, it is linked with oxidative stress, inflammation, and apoptosis, which may harmfully affect the brain. Hypericum perforatum L. (HP L.) is a strong medicinal plant, but its hydrophobic polyphenolic compounds limit its activity. Therefore, our study aimed to investigate the neuroprotective action of HP L. and its nanoemulsion (NE) against Cis-induced neurotoxicity. The prepared HP.NE was subjected to characterization. The droplet size distribution, surface charge, and morphology were evaluated. In addition, an in vitro dissolution study was conducted. Compared to Cis-intoxicated rats, HP L. and HP.NE-treated rats displayed improved motor activity and spatial working memory. They also showed an increase in their antioxidant defense system and a reduction in the levels of pro-inflammatory cytokines in the brain. Moreover, they showed an increase in the expression levels of the PON-3 and GPX genes, which are associated with a reduction in the brain levels of COX-2 and TP-53. These findings were confirmed by reducing the immunohistochemical expression of nuclear factor kappa (NF-ƘB) and enhanced Ki-67 levels. In conclusion, HP L. is a promising herb and could be used as an adjuvant candidate to ameliorate chemotherapeutic-induced neurotoxicity. Moreover, HP.NE has superior activity in lessening Cis-induced oxidative stress, inflammation, and apoptosis in brain tissue.