Pharmacokinetic study of eight coumarins of Radix Angelicae Dahuricae in rats by gas chromatography–mass spectrometry

PIDA-promoted metal-free [3 + 2] heteroannulation of β-ketothioamides with 4-hydroxy coumarins: chemo-/regioselective access to furo[3,2-c]chromen-4-ones at room temperature

Herein, we report a viable protocol to access furo[3,2-c]chromen-4-ones by engaging easily accessible 4-hydroxy coumarins as a three-atom CCO unit and thioamides as a C2 coupling partner, mediated by phenyliodine(III) diacetate (PIDA) at room temperature in a highly efficient and pot-/step-economical manner. This strategy not only avoids potential toxicity and tiresome workup conditions, but also features operational simplicity, a broad substrate scope, good functional group tolerance, high yields, easy scalability and exclusive selectivity. A mechanistic study has shown that this metal-free reaction is triggered by PIDA via activation of the β-carbon of 4-hydroxy coumarin, followed by a nucleophilic addition/intramolecular cyclization/dethiohydration cascade. High-resolution mass spectra (HRMS) study confirms the key intermediates involved during the course of the reaction, elucidating the reaction pathways, and demonstrates the excellent regio- and chemoselectivity of this approach.

Temperature-Controlled Chemoselective Synthesis of Multisubstituted 4-Alkynyl/trans 4-Alkenyl Coumarins

A temperature-controlled facile synthesis of multisubstituted 4-alkynyl/trans 4-alkenyl coumarins with a metal salt cascade approach is reported. H₂O serves both as a nucleophile and hydrogen source. The presence of metal salt facilitates the reduction of alkyne. The present protocol bypasses the structural shortcomings of the existing Sonogashira and Heck coupling reactions. In addition, the obtained 2,3-disubstituted coumarins are readily transformed into 2,3-disubstituted dihydrocoumarins, which serve as important building blocks in organic transformations.

Detection of the Content of Two Coumarins, IM and ISOIM, and Their Mechanism of Action on Colitis Rats in Angelica albicans

Angelica albicans is being used in the cure of different, respiratory, neuromuscular, and cutaneous diseases in traditional eastern medicine. The pharmacokinetic (PK) characteristics of imperatorin (IM) and isoimperatorin (ISOIM), the main effective components in Angelica albicans, were investigated. The rapid, subtle, and measuring the PKs of a drug, a validated UPLC/MS/MS methodology was designed for a total of 2 furanocoumarins in 2,4,6-trinitrobenzene sulfonic acid-stimulated and untreated mice. After that, blood samples were obtained. Angelica albicans (0.5 and 1.0 g/kg) was given orally, taken regularly from the tail vein. The time it takes for colitis rats to achieve their maximal concentration (T_max) imperatorin and isoimperatorin was considerably postponed. In comparison to normal rats, all furanocoumarins had lesser peak plasma concentrations (C_max) and higher represent residence durations. The area below the C_max time-curve or clearance half-life did not differ significantly. In normal rats, all two furanocoumarins attained maximal plasma levels between 40 and 75 minutes, demonstrating fast oral absorption. The periods to attain T_max of the two furanocoumarins, on the other hand, were shorter than in earlier studies. Therefore, colitis-linked alterations in the drug-absorption stage may result in a late T_max and lowered C_max, which have no effect on its clearance in half-life. Hence, conclusively, as a result, more consideration should be given to the prescription and administration of Angelica albicans in colitis individuals, and more research is needed to determine whether the changed PK profile was clinically meaningful for medicinal dose.

The Angelica dahurica: A Review of Traditional Uses, Phytochemistry and Pharmacology

Angelica dahurica (A. dahurica) root is a famous edible medicinal herb that has been used in China for thousands of years. To date, more than 300 chemical constituents have been discovered from A. dahurica. Among these ingredients, coumarins and volatile oils are the major active compounds. Moreover, a few other compounds have also been isolated from the root of A. dahurica, such as alkaloids, phenols, sterols, benzofurans, polyacetylenes and polysaccharides. Modern pharmacological studies demonstrated that the root of A. dahurica and its active components displayed various bioactivities such as anti-inflammation, anti-tumor, anti-oxidation, analgesic activity, antiviral and anti-microbial effects, effects on the cardiovascular system, neuroprotective function, hepatoprotective activity, effects on skin diseases and so on. Based on these studies, this review focused on the research publications of A. dahurica and aimed to summarize the advances in the traditional uses, phytochemistry and pharmacology which will provide reference for the further studies and applications of A. dahurica.

Preclinical Pharmacokinetics and Bioavailability of Oxypeucedanin in Rats after Single Intravenous and Oral Administration

Oxypeucedanin, a furanocoumarin extracted from many traditional Chinese herbal medicines, has a variety of pharmacological effects. However, the independent pharmacokinetic characteristics and bioavailability of this compound remains elusive. In this study, a rapid, sensitive, and selective method using ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC/MS/MS) was developed for evaluating the intravenous and oral pharmacokinetics of oxypeucedanin. After intravenous administration of oxypeucedanin (2.5, 5, and 10 mg/kg), and intragastric administration of oxypeucedanin (20 mg/kg), blood samples were collected periodically from the tail vein. The plasma concentration-time curves were plotted, and the pharmacokinetic parameters were calculated using a non-compartmental model analysis. After intravenous administration of oxypeucedanin (single dosing at 2.5, 5, and 10 mg/kg) to rats, the pharmacokinetics fit the linear kinetics characteristics, which showed that some parameters including average elimination half-life (T_1/2Z of 0.61~0.66 h), mean residence time (MRT of 0.62~0.80 h), apparent volume of distribution (V_Z of 4.98~7.50 L/kg), and systemic clearance (CL_Z of 5.64~8.55 L/kg/h) are dose-independent and the area under concentration-time curve (AUC) increased in a dose-proportional manner. Single oral administration of oxypeucedanin (20 mg/kg) showed poor and slow absorption with the mean time to reach the peak concentration (T_max) of 3.38 h, MRT of 5.86 h, T_1/2Z of 2.94 h, and a mean absolute bioavailability of 10.26% in rats. These results provide critical information for a better understanding of the pharmacological effect of oxypeucedanin, which will facilitate its research and development.

A review on convenient synthesis of substituted coumarins using reuseable solid acid catalysts

Due to growing concern about chemicals and their impact on the environment, cleaner reaction conditions are needed to be incorporated into chemical synthetic procedures. Recently, the use of heteropolyacid catalysts, mainly reuseable solid acid catalysts, has gained a leading role in organic synthesis due to their environmental and economic considerations and industrial utilization. The high catalytic activity, moisture sensitivity, reusability and inexpensive makes solid supported reagents attractive substituents to conventional Lewis acids. Nowadays synthesis of coumarins and their derivatives has attracted considerable attention from organic and medicinal chemists for many years as a large number of natural products contain this heterocyclic nucleus. In continuation with our investigations into the synthesis of substituted coumarins and due to several advantages of heterogeneous catalysts viz. cost-effective, no side products, high yield of desired products and no toxic waste material, here we report a new approach for the synthesis of substituted coumarins using solid acid catalysts.

Anti-Cancer and Anti-Inflammatory Potential of Furanocoumarins from Ammi majus L

Secondary metabolites have potential benefits to human being. They are used in the food, agricultural and pharmaceutical industries. The secondary metabolite of furanocoumarins from different plant sources is essential in various skin-related ailments. Biologically, these chemicals are isolated from different plants in the Apiaceae, Fabaceae, Rutaceae and Moraceae families. Ammi Majus L. is one of the most common plants in the family of Apiaceae with a large quantity of derivatives. The furanocoumarin derivatives defend the plant by fighting external enemies by systemic acquired resistance (SAR). Via suppressing or retarding microbial growth in infected parts, these derivatives, along with SAR, help to alleviate inflammation in the human body. Latest evidence of these compounds has been established in the treatment of cancer, but the mechanism that needs to be elaborated is not yet understood. Recent studies have shown that furanocoumarin derivatives bind to DNA base pairs and block DNA replication. This may be a potential pathway that helps to regulate the growth of cancerous cells. This article reflects on the pharmaceutical data of furanocoumarins and their different mechanisms in these cases.

Oxypeucedanin: Chemotaxonomy, Isolation, and Bioactivities

The present review comprehensively gathered phytochemical, bioactivity, and pharmacokinetic reports on a linear furanocoumarin, namely oxypeucedanin. Oxypeucedanin (OP), which structurally contains an epoxide ring, has been majorly isolated from ethyl acetate-soluble partitions of several genera, particularly Angelica, Ferulago, and Prangos of the Apiaceae family; and Citrus, belonging to the Rutaceae family. The methanolic extract of Angelica dahurica roots has been analytically characterized as the richest natural OP source. This naturally occurring secondary metabolite has been described to possess potent antiproliferative, cytotoxic, anti-influenza, and antiallergic activities, as assessed in preclinical studies. In order to explore potential drug candidates, oxypeucedanin, its derivatives, and semi-synthetically optimized analogues can be considered for the complementary assessments of biological assays.

Understanding the phytochemistry and molecular insights to the pharmacology of Angelica archangelica L. (garden angelica) and its bioactive components

Plant-derived molecules have enduring usefulness in treating diseases, and herbal drugs have emerged as a vital component of global therapeutic demand. Angelica archangelica L. (A. archangelica), commonly known as garden angelica, is an aromatic food plant used in culinary procedures as a flavoring agent. In the traditional medicine system, it is regarded as an "Angel plant" due to its miraculous curative power. This review aims to provide a comprehensive summary of the plant's taxonomic profile, ethnopharmacology, Phytochemistry, and pharmacological activities. Various in vivo and in vitro experiments have validated that the plant possesses broad pharmacological potential. The biological activities attributed to the plant include anti-anxiety activity, anti-convulsant activity, cognition enhancer, antiviral activity, cholinesterase inhibitory potential, antiinflammatory activity, gastroprotective activity, and radioprotective activity. The beneficial effects of the plant are credited to its bioactive components, that is, coumarins and volatile oils. The review summarizes the pharmacological activities of crude extract and its bioactive fractions and has also explored their target-oriented effects. This review will be of value in undertaking further investigations on the plant with regard to exploring mechanism-based pharmacological approaches on A. archangelica.

The Use of 1H-qNMR Method for Simultaneous Determination of Osthol, Columbianadin, and Isoimperatorin in Angelicae Pubescentis Radix

OBJECTIVE

The goal of this work was to establish a method to identify and quantify the main active components in Angelicae Pubescentis Radix (APR) quickly, simply, and accurately. This paper reports a novel method which can determine osthol, isoimperatorin, and columbianadin using 1H-qNMR simultaneously and quantitatively.

METHODS

In comprehensive consideration of resolution of target signals and the solubility of materials, dimethyl sulfoxide-d6 (DMSO-d6) was selected as an optimal 1H-qNMR solvent and pyrazine was used as internal standard substance (δ8.66 ppm). The quantitative peaks of three active components were determined using specific 1H resonances at δ7.54-7.56 ppm for osthol, δ6.83-6.85 ppm for columbianadin, and δ6.31-6.32 ppm for isoimperatorin.

RESULTS

The results show that the method has good precision, stability, and repeatability. The content of APR plant material from Huating is 9.8 mg/g, 5.6 mg/g, and 15.6 mg/g for osthol, columbianadin, and isoimperatorin, respectively. Furthermore, the experimental process is simple and the test time is short (1 min).

CONCLUSIONS

The proposed quantitative 1H-qNMR methodology can be used for the quality control of APR.

Multi-Index Quantitative Evaluation of Angelicae sinesis Radix Based on 1H-qNMR

BACKGROUND

As known to us, HPLC method was often used to determine the contents of Angelicae sinesis Radix. In view of the shortcomings of HPLC method, qNMR has prominent advantages in determining the contents of bioactive components in the quantitative and qualitative analysis of Angelicae sinesis Radix.

OBJECTIVE

In this study, a quick, simple, and accurate method was established to determine the components of ferulic acid, coniferyl ferulate, and ligustilide in Angelicae sinesis Radix.

METHOD

Using dimethyl sulfoxide-d6(DMSO-d6) as the test solvent and pyrazine as the internal standard substance, 1H-qNMR measurement was performed on a 600 MHz spectrometer. The quantitative resonance peaks of pyrazine, ferulic acid, ligustilide, and coniferyl ferulate were at δ8.66 ppm, δ6.35-6.37 ppm, δ5.53-5.55 ppm, and δ6.50-6.53 ppm, respectively.

RESULTS

The linear relationship, limit of detection, limit of quantification, precision, stability, and recovery were verified and the results were good. On the other hand, it was verified by HPLC, and the HPLC used for verification passed the methodological investigation of linearity, precision, repeatability, stability, and recovery, and the results were good. In addition, no significant difference in results was found between the 1H-qNMR and HPLC-UV methods in determining the content of three components in three batches of Angelicae sinesis Radix.

CONCLUSIONS

The method can be used for simultaneous determination of three active components, and providing a scientific basis for the overall quality evaluation and quality control of Angelicae sinesis Radix.

HIGHTLIGHTS

In this study, 1H-qNMR was used to determine ferulic acid, coniferyl ferulate and ligustilide in Angelicae Sinensis Radix for the first time.

Progress in Pretreatment and Analytical Methods of Coumarins: An Update since 2012 - A Review

Coumarins are widely used due to their wide range of biological activities, but the long-term or excessive use of coumarin flavors can pose serious health hazards. Therefore, sensitive and specific methods for the quantification of these compounds in different matrices have been developed. In this review, an updated overview of the latest trends in sample preparation techniques and methods used to detect coumarins from March 2012 to April 2019 is provided. This study reviews different analytical methods (such as liquid chromatography coupled with different detectors, electrochemical sensors, capillary electrophoresis, etc.) and different pretreatment methods (such as liquid-liquid extraction, solid-phase extraction, dispersive liquid-liquid microextraction, etc.). Different methods for the pretreatment and determination of coumarins in plant, food, environmental, pharmaceutical and biological samples are summarized, discussed and compared.HighlightsProgress in pretreatment and analytical methods of coumarins are summarized.Fundamentals, instrumentation and applications of purification and quantification are summarized and compared.Optimization of experimental conditions are discussed.Newly emerged eco-friendly methods are introduced.

Effects of imperatorin in the cardiovascular system and cancer

Patients with cancer survivors are at increased risk of cardiovascular disease(CVD). Cardio-oncology has developed as a new discipline with the advances in cancer treatment. There are many new challenges for the clinician and a new frontier for research and investigation. There is an urgent need for further study on the prevention of cardiovascular toxicity. Imperatorin (IMP) is a natural form of coumarin and extract from several plants with diver's pharmacokinetic effects, including antioxidant and anti-inflammatory properties. This review focus on the molecular mechanisms and pharmacological effects of Imperatorin maybe provide potential cancer and cardiovascular protection that targets IMP. Further studies are required to elucidate the entire spectrum of cytotoxic activities of these compounds to validate and expand their preclinical and clinical applications and to clarify the potential role of IMP.

Separation and determination of coumarins including furanocoumarins using micellar electrokinetic capillary chromatography

The conditions of micellar electrokinetic capillary chromatography for separation and simultaneous measurement of coumarins (coumarin, scoparone, isoscopoletin, esculin, esculetin, umbelliferone) including furanocoumarins (xanthotoxin, byakangelicin, isopimpinellin, bergapten, phellopterin, xanthotoxol) have been elaborated. The influence of different parameters, such as the pH of the buffer, sodium cholate (SC) or methanol concentration in the buffer, on the migration time, peak resolution, peak asymmetry, and number of theoretical plates was investigated. The optimum separation of the compounds was achieved using 50-µm i.d. capillaries with a total length of 64.5 cm (56 cm effective length) and a buffer system at pH 9.00 consisting of 50 mM sodium tetraborate, 45 mM SC, and 20% of methanol (v/v). The developed method ensured good repeatability of corrected peak areas and migration times (the relative standard deviations were in the range of 2.8-6.1% and 0.8-4.0%, respectively). The average limit of detection for all studied compounds was below 1.3 µg mL. Moreover, good linearity of the relationship between the peak corrected area and the concentration of the compounds was observed (correlation coefficient >0.99). The method was successfully applied in the quantitative analysis of two different types of samples, i.e. Heracleum sphondylium herb and Aesculus hippocastanum cortex.

Different effects of (+)‑borneol and (‑)‑borneol on the pharmacokinetics of osthole in rats following oral administration

Osthole is the primary active component of a number of herbal plants such as the Cnidium monnieri fruit. In traditional Chinese herb medicine, osthole is commonly used in combination with borneol to obtain improved pharmacological effects. The aim of the present study was to investigate the effect of borneol enantiomers on the pharmacokinetics of osthole. An appropriate high‑performance liquid chromatography (HPLC) method was applied to determine the concentrations of osthole in plasma. Following oral administration of osthole alone or combined with borneol in rats, blood samples were collected and analyzed by HPLC. The results demonstrated that there were statistically significant differences in the pharmacokinetic parameters of osthole between osthole administration alone and co‑administration with borneol. When combined with synthetic borneol, the AUC0‑t, AUC0‑∞ and Cmax of osthole increased by 48.153, 104.708 and 92.630%, respectively, while the CL/F decreased by 51.251%. When combined with (+)‑borneol, the AUC0‑t, AUC0‑∞ and Cmax of osthole were increased by 61.561, 78.167, and 51.769%, respectively, while the CL/F decreased by 44.174% (P<0.01). In addition, when combined with (‑)‑borneol, the AUC0‑t, AUC0‑∞ and Cmax of osthole increased by 115.856, 167.786 and 271.289%, respectively, while the CL/F decreased by 60.686% (P<0.01). These results indicated that borneol may enhance gastrointestinal absorption and inhibit the metabolism of osthole. In addition, the promotional effect of (‑)‑borneol on the pharmacokinetic parameters of osthole was greater than that of (+)‑borneol.

Anti-inflammatory and cytotoxic effects of methanol, ethanol, and water extracts of Angelicae Dahuricae Radix

Angelicae Dahuricae Radix has been used for the treatment of headaches, rhinitis, and colds in traditional medicine. Methanol, ethanol, and water extracts of Angelicae Dahuricae Radix were collected. A statistically significant reduction in the cellular viability of the mouse leukemic monocyte macrophage cell line was noted after treatment with water extracts of Angelicae Dahuricae Radix. Stimulation with lipopolysaccharides (LPS) for 24 h led to a robust increase in nitric oxide production, but Angelicae Dahuricae Radix at 400 μg/mL concentration significantly suppressed nitric oxide produced by the LPS-stimulated RAW 264.7 cells in 70% ethanol, absolute ethanol, 70% methanol, absolute methanol, and boiling water groups (P < 0.05). Pretreatment with absolute ethanol extract of Angelicae Dahuricae Radix suppressed the LPS-stimulated inducible nitric oxide synthase, interleukin-1β, and cycloxygenase-2 expression. Angelicae Dahuricae Radix showed significant cytotoxic effects on the human adenocarcinoma cell line and keratin-forming cell line. (J Oral Sci 58, 125-131, 2016).

Simultaneous Determination of Three Furanocoumarins by UPLC/MS/MS: Application to Pharmacokinetic Study of Angelica dahurica Radix after Oral Administration to Normal and Experimental Colitis-Induced Rats

In traditional oriental medicine, Angelica dahurica Radix (ADR) is used in the treatment of gastrointestinal, respiratory, neuromuscular, and dermal disorders. We evaluated the pharmacokinetic profiles of oxypeucedanin, imperatorin, and isoimperatorin, major active ingredients of ADR, in normal and 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis rats. A rapid, sensitive, and validated UPLC/MS/MS method was established for evaluating the pharmacokinetics of three furanocoumarins. After oral administration of ADR (0.5 and 1.0 g/kg), blood samples were collected periodically from the tail vein. In colitis rats, the time to reach the peak concentration (T_max) of imperatorin and isoimperatorin was significantly delayed (p < 0.05). Lower peak plasma concentrations (C_max) and longer mean residence times for all furanocoumarins were also observed (p < 0.05) compared with normal rats. There was no significant difference in the area under the plasma concentration-time curve or elimination half-lives. Thus, the delayed T_max and decreased C_max, with no influence on the elimination half-life, could be colitis-related changes in the drug-absorption phase. Therefore, the prescription and use of ADR in colitis patients should receive more attention.

Inhibition of melatonin metabolism in humans induced by chemical components from herbs and effective prediction of this risk using a computational model

BACKGROUND AND PURPOSE

Herbs which are widely used as food and medicine, are involved in many physiopathological processes. Melatonin is a human hormone, synthesized and secreted by the pineal gland, with a range of biological functions. Here, we have evaluated the potential influences of components extracted from common herbs on melatonin metabolism in humans.

EXPERIMENTAL APPROACH

An in vivo pharmacokinetic study involving 12 healthy subjects, in vitro incubations with human liver microsomes (HLMs) and recombinant human cytochrome P (CYP) isoenzymes and an in silico quantitative structure-activity relationship (QSAR) model analysis using comparative molecular field analysis and comparative molecular similarity indices analysis methods were employed to explore these interactions.

KEY RESULTS

After systematic screening of 66 common herbs, Angelica dahurica exhibited the most potent inhibition of melatonin metabolism in vitro. The in vivo pharmacokinetic study indicated inhibition of melatonin metabolism, with approximately 12- and 4-fold increases in the AUC and C_max of melatonin in human subjects. Coumarins from A. dahurica, including imperatorin, isoimperatorin, phellopterin, 5-methoxypsoralen and 8-methoxypsoralen, markedly inhibited melatonin metabolism with K_i values of 14.5 nM, 38.8 nM, 6.34 nM, 5.34 nM and 18 nM respectively, through inhibition of CYP 1A2, 1A1 and 1B1 in HLMs. A QSAR model was established and satisfactorily predicted the potential risk of coumarins for inhibition of melatonin metabolism in vivo.

CONCLUSION AND IMPLICATIONS

Coumarins from A. dahurica inhibited melatonin metabolism in vivo and in vitro. Our findings provide vital guidance for the clinical use of melatonin.

Simultaneous determination and pharmacokinetics of sixteen Angelicae dahurica coumarins in vivo by LC-ESI-MS/MS following oral delivery in rats

BACKGROUND

The roots of Angelica dahurica cv. Qibaizhi is frequently used in clinical practice as a traditional Chinese medicine. However, a comprehensive study of the pharmacokinetics of this medicine has not been carried out.

METHOD

A sensitive and specific liquid chromatographic-tandem mass (LC-MS/MS) spectrometric method was established to investigate pharmacokinetics of sixteen coumarins of Angelicae dahuricae Radix (ADR) in rat plasma, including xanthotoxol (1), oxypeucedanin hydrate (2), 5-hydroxy-8-methoxypsoralen (3), (-)-marmesin (4), byakangelicin (5), columbianetin (6), psoralen (7), xanthotoxin (8), neobyakangelicol (9), isoimpinellin (10), bergapten (11), heraclenin (12), oxypeucedanin ethanolate (13), imperatorin (14), phellopterin (15), isoimperatorin (16). Detection was performed on a triple quadrupole mass spectrometer in multiple-reaction-mode (MRM).

RESULTS

The method established in this assay was successfully applied to the pharmacokinetic study of the selected coumarins in rat plasma after oral administration of the extract of ADR, and the pharmacokinetic characteristics of sixteen coumarins were clearly elucidated.

CONCLUSION

This pharmacokinetic identification of multiple coumarins of ADR in rats provides a significant basis for better understanding the metabolic mechanism of the herb medicine.

Determination of coumarins in the roots of Angelica dahurica by supercritical fluid chromatography

The fact that supercritical fluid chromatography (SFC) offers many desirable features is known for a long time. Yet, the number of applications on natural products is still limited, because robust and user-friendly instrumentation became available just a few years ago. As coumarins hardly have been studied by this technique we developed the first SFC assay for their determination in crude plant material. After method optimization eight standard compounds, including simple coumarins, linear and angular furanocoumarins, could be baseline separated in 6min using an Acquity UPC(2) CSH Fluoro-Phenyl 1.7μm column with supercritical CO2, methanol and diethylamine as mobile phase. Method validation confirmed that the assay is linear (R(2)≥0.9995), precise (intra-day variation≤5.8%; inter-day variation≤4.4%) and accurate (recovery rates from 96.5 to 104.2%). Detection limits determined at 300nm were below 2ng on-column, and the method showed to be well suited for the analysis of coumarins in Angelica dahurica roots. It was observed that qualitative as well as quantitative composition vary significantly. In all samples Imperatorin (0.09-0.28%) was the major coumarin, followed either by Isoimperatorin or Oxypeucedanin; the total coumarin content ranged from 0.16 to 0.77%. The results were in good agreement to published data, so that because of its speed and green nature SFC is definitely an interesting alternative for the analysis of this important class of natural products.

Imperatorin-pharmacological meaning and analytical clues: profound investigation

Imperatorin, a furanocoumarin derivative, has many documented pharmacological properties which make it a candidate for possible drug development. In this review, the activity on the central nervous system, the anticancer and antiviral properties and the influence on the cardiovascular system are described. The aim of this review is also to present an overview of the techniques used for the analysis, isolation, and separation of imperatorin from plant material from the practical perspective.

Novel synthesis of coumarin-containing secondary benzamide derivatives using tungstate sulfuric acid

A novel one-pot synthesis of coumarin-containing secondary benzamide derivatives is described using tungstate sulfuric acid as a reusable heterogeneous catalyst.

Separation and simultaneous quantification of nine furanocoumarins from Radix Angelicae dahuricae using liquid chromatography with tandem mass spectrometry for bioavailability determination in rats

Radix Angelicae dahuricae is a well-known medicinal herb in a number of herb preparations for medical uses. In this study, a rapid and selective method using liquid chromatography with tandem mass spectrometry was developed for the separation and simultaneous quantitation of nine furanocoumarins from Radix A. dahuricae, namely imperatorin, isoimperatorin, oxypeucedanin hydrate, bergapten, oxypeucedanin, xanthotoxol, xanthotoxin, isopimpinellin, and psoralen. Chromatographic separation was achieved on a CAPCELL PAK MG II C18 analytical column. Detection was performed using positive electrospray ion source in the multiple reaction monitoring mode. The method was fully validated for analyzing these principles in rat plasma with a lower limit of quantification from 0.5 to 5 ng/mL. The intra- and interbatch precisions were less than 10%, and the accuracies ranged from -7.5 to 8.0%. The extraction recovery of the analytes was above 70% without a significant matrix effect. The method was used to determine the oral and intravenous pharmacokinetic profiles of these furanocoumarins after dosing with Radix A. dahurica extract. The bioavailability of these furanocoumarins ranged from 10.1 to 82.8%. These data provide critical information for a better understanding of the pharmacological mechanisms and herb-drug interaction potential of Radix A. dahurica.

Ex Vivo and In Situ Evaluation of 'Dispelling-Wind' Chinese Medicine Herb-Drugs on Intestinal Absorption of Chlorogenic Acid

This study aims to investigate the additive or synergistic effects and mechanism of intestinal absorption of extracts from two commonly used 'dispelling-wind' TCM botanical drugs [roots of Angelica dahurica (Hoffm.) Benth. & Hook. f. ex Franch. & Sav. (RAD) and Saposhnikovia divaricata (Turcz.) Schischk. (RSD)] using chlorogenic acid as a marker substance. Ex vivo everted intestinal sac and in situ single pass perfusion methods using rats were employed to investigate the effects of two TCM botanical drugs extracts on the intestinal absorption of chlorogenic acid. Both the extracts of RAD and RSD showed synergistic properties on the intestinal absorption of chlorogenic acid. The verapamil (a P-gp inhibitor) and intestinal dysbacteriosis model induced by norfloxacin increased the P(app) and K(a) of intestinal absorption of chlorogenic acid. These synergistic effects on intestinal absorption in a rat model can be correlated with the inhibition of P-gp and regulation of gut microbiota. This experimental approach has helped to better understand changes in the absorption of chlorogenic acid under different conditions.

Evaluation of the effects of Angelicae dahuricae radix on the morphology and viability of mesenchymal stem cells

Angelicae dahuricae radix is a traditional herbal medicine used to treat various diseases in China and Korea, such as colds, headaches, rhinitis and psoriasis. Angelicae dahuricae radix has been used as an anti-inflammatory, analgesic, antipyretic and antioxidant remedy. This study was performed in order to evaluate the effects of the extracts of Angelicae dahuricae radix on the morphology and viability of mesenchymal stem cells derived from the gingiva. Mesenchymal stem cells derived from the gingiva were grown in the presence of Angelicae dahuricae radix at final concentrations that ranged from 0.001 to 100 µg/ml. The morphology of the cells was viewed under an inverted microscope, and the analysis of cell proliferation was performed with cell counting kit-8 (CCK-8) on days 1, 3 and 7. The cells in the control group had spindle-shaped, fibroblast-like morphology at days 1, 3 and 7 under optical microscopy. The shapes of the cells in 0.001, 0.01, 0.1, 1, 10 and 100 µg/ml Angelicae dahuricae radix were similar to the shapes of the cells in the control group. The relative values of the CCK-8 assays of 0.001, 0.01, 0.1, 1, 10, and 100 µg/ml Angelicae dahuricae radix were 102.5 ± 0.6, 133.3 ± 9.6, 148.4 ± 20.5, 147.7 ± 12.6, 132.3 ± 27.7 and 101.1 ± 4.6%, respectively, when the CCK-8 result of the control group on day 1 was considered to be 100%. There was a marginal increase in cell proliferation at 0.1 and 1 µg/ml groups at day 1; however, this did not achieve statistical significance (P=0.052). The relative values of the CCK-8 assays of 0.001, 0.01, 0.1, 1, 10 and 100 µg/ml Angelicae dahuricae radix were 96.5 ± 1.3, 89.3 ± 0.9, 90.3 ± 3.0, 84.8 ± 12.2, 92.3 ± 4.5 and 86.8 ± 11.7%, respectively, when the CCK-8 result of the control group on day 3 was considered to be 100% (P>0.05). The relative values of the CCK-8 assays of 0.001, 0.01, 0.1, 1, 10 and 100 µg/ml Angelicae dahuricae radix day 7 were 94.9 ± 22.3, 102.8 ± 22.1, 127.4 ± 7.4, 130.4 ± 1.3, 129.2 ± 10.8 and 124.8 ± 9.1%, respectively, when the CCK-8 result of the control group on day 7 was considered to be 100%, but there were no statistically significant differences among the groups (P>0.05). Within the limits of this study, Angelicae dahuricae radix at the tested concentrations did not produce statistically significant differences in the viability of stem cells derived from the gingiva.

Vasodilation and radical-scavenging activity of imperatorin and selected coumarinic and flavonoid compounds from genus Casimiroa

Hypertension is a very widespread condition which is not strictly considered as an illness but if not countered, progressively causes damage to all tissues and loss in their functionality. For this reason the find of new antihypertensive agents is prominent and medicinal plants and their derivatives are valuable for the purpose. The genus Casimiroa (Rutaceae) includes plants from Central America and Mexico; among these, Casimiroa edulis Llave et Lex. and Casimiroa pubescens Ramirez are the most relevant species, even for their medicinal uses. The decoction of leaves and seeds is traditionally taken as a tea mainly to lower blood pressure. The object of this research was the study of vascular activity of coumarinic and flavonoid compounds isolated from seeds of Casimiroa spp. in comparison with Casimiroa edulis and Casimiroa pubescens extracts. The phenolic compounds isolated from Casimiroa were herniarin (Her), imperatorin (Imp), 8-geranyloxypsoralen (GOP) and 5,6,2',3',4'-pentamethoxyflavone (PMF). All these compounds induced vasorelaxation on rat arterial tissues although with different effectiveness. To study the cellular mechanisms of the vasorelaxation exhibited by imperatorin, we used selective inhibitors of different receptors and enzymes, such as atropine, pyrilamine, nifedipine, L-NAME and DETC. In a further step of this research, we evaluated the radical-scavenging activity of Casimiroa extracts and isolated compounds by means of DPPH assay. In general, we observed that the scavenging activities increased in a concentration-dependent manner for all substances. The phenolic compounds highlight a synergism of vasodilation and antioxidant activity which may be very useful in the management of cardiovascular diseases. Among the evaluated compounds, imperatorin shows a significant vasorelaxant activity even higher than acetylcholine and similar to nitrite, and also useful antiradical capabilities. All these properties suggest its possible role against hypertension and vasculopathies, even if in vivo studies are needed to determine the actual applications.

Suppression of voltage-gated Na(+) channels and neuronal excitability by imperatorin

Imperatorin is a naturally occurring furocoumarin compound isolated from plants such as Angelica archangelica and Cnidium monnieri. It has multiple pharmacological effects including anticonvulsant effects. Here we determined the effects of imperatorin on voltage-gated Na(+) channels (VGSC) using whole-cell patch clamp techniques in differentiated neuronal NG108-15 cells. We showed that imperatorin inhibited VGSC; such inhibition did not show state-dependence. Imperatorin caused a left shift in the steady-state inactivation curve without affecting activation gating. The inhibition of VGSC by imperatorin displayed a mild frequency-dependence. Imperatorin was also shown to inhibit VGSC and action potential amplitude without affecting voltage-gated K(+) channels in rat hippocampal CA1 neurons. In conclusion, our results suggest that imperatorin dampens neuronal excitability by inhibiting VGSC.