Linear Furanocoumarins Research Articles

Preparation, Characterization, and Pharmacokinetic Evaluation of Imperatorin Lipid Microspheres and Their Effect on the Proliferation of MDA-MB-231 Cells.

Imperatorin is a chemical compound belonging to the linear furanocoumarins. Imperatorin is attracting considerable attention because of its antitumor, antibacterial, anti-inflammatory, and anticoagulant activities, inhibition of myocardial hypertrophy, and other pharmacological efficacies. However, imperatorin has limited water solubility and has better lipid solubility; thus, we decided to design and synthesize imperatorin lipid microspheres to optimize the preparation conditions. The aim was to develop and formulate imperatorin lipid microspheres through nanoemulsion technology and apply the response surface–central composite design to optimize the imperatorin lipid microsphere formulation. The influence of the amounts of egg lecithin, poloxamer 188, and soybean oil for injection on the total percentage of the oil phase was investigated. The integrated effect of dependent variables, including particle size, polydispersity index, zeta potentials, drug loading, and encapsulation efficiency, was investigated. Data of overall desirabilities were fitted to a second-order polynomial equation, through which three-dimensional response surface graphs were described. Optimum experimental conditions were calculated by Design-Expert 8.06. Results indicated that the optimum preparation conditions were as follows: 1.39 g of egg lecithin, 0.21 g of poloxamer 188, and 10.57% soybean oil for injection. Preparation of imperatorin lipid microspheres according to the optimum experimental conditions resulted in an overall desirability of 0.7286, with the particle size of 168 ± 0.54 nm, polydispersity index (PDI) of 0.138 ± 0.02, zeta potentials of −43.5 ± 0.5 mV, drug loading of 0.833 ± 0.27 mg·mL−1, and encapsulation efficiency of 90 ± 1.27%. The difference between the observed and predicted values of the overall desirability of the optimum formulation was in the range from 2.4% to 4.3%. Subsequently, scanning electron microscopy was used to observe the micromorphology of the imperatorin lipid microspheres, showing round globules of relatively uniform shape and sizes within 200 nm. The effect of imperatorin lipid microspheres on MDA-MB-231 proliferation was investigated by the MTT method. Furthermore, pharmacokinetics in Sprague-Dawley rats was evaluated using orbital bleeding. A sensitive and reliable liquid chromatography with the high-performance liquid chromatography (HPLC) method was established and validated for the quantification of imperatorin in rat plasma samples. The data were calculated by DAS (drug and statistics) Pharmacokinetic Software version 3.3.0 (Version 3.3.0, Shanghai, China). Results demonstrated that imperatorin lipid microspheres can significantly enhance the bioavailability of imperatorin and can significantly inhibit MDA-MB-231 cell proliferation. In conclusion, our results suggested that the response surface–central composite design is suitable for achieving an optimized lipid microsphere formulation. Imperatorin lipid microspheres can improve the bioavailability of imperatorin and better inhibit the proliferation of MDA-MB-231 cells as compared to imperatorin alone.

Imperatorin Targets MCL-1 to Sensitize CD133+ Lung Cancer Cells to γδ-T Cell-Mediated Cytotoxicity

Background/Aims: CD133⁺ cancer cells display low sensitivity to anti-cancer treatment; thus, combination treatment with adjuvant drugs is required to improve the efficiency of cancer therapy. The aim of this study was to explore the effect of imperatorin, a linear furanocoumarin compound, on γδ T cell-mediated cytotoxicity against CD133⁺ lung cancer cells. Methods: CD133⁺ and CD133^- subgroups from A549 and PC9 lung cancer cells were sorted by using flow cytometry. The cytotoxicity of γδ T cells against cancer cells was evaluated by measuring lactate dehydrogenase release. The concentration of tumor necrosis factor-related apoptosis-inducing ligand in the co-culture system was determined by using an enzyme-linked immunosorbent assay. Mitochondrial membrane potential, expression of death receptor 4 (DR4) and DR5 on the cell surface, and rate of apoptosis were measured by flow cytometry. Cytochrome c release and cellular protein expression were detected by western blot analysis. Results: Compared with CD133^- cells, CD133⁺ cells were resistant to γδ T cell-mediated cytotoxicity. However, imperatorin significantly increased the sensitivity of CD133⁺ lung cancer cells to γδ T cell treatment in vitro and in vivo. Mechanically, we found that myeloid cell leukemia 1 (MCL-1), an important anti-apoptotic protein belonging to the Bcl-2 family, was overexpressed in CD133⁺ A549 and PC9 cells compared to their corresponding CD133^- cells. Co-treatment with imperatorin and γδ T cells suppressed the expression of MCL-1, and thus promoted the mitochondrial apoptosis mediated by γδ T cells in CD133⁺ A549 and PC9 lung cancer cells. Conclusion: Up-regulated MCL-1 in CD133⁺ lung cancer cells is responsible for their resistance to γδ T cells. Furthermore, the combination of γδ T cells with imperatorin sensitized CD133⁺ lung cancer cells to γδ T cell-mediated cytotoxicity by targeting MCL-1.

Design, Synthesis and Antifungal Activity of Psoralen Derivatives.

A series of linear furanocoumarins with different substituents have been designed and synthesized. Their structures were confirmed by 1H-NMR spectroscopy, high resolution mass spectra (EI-MS), IR, and X-ray single-crystal diffraction. All of the target compounds were evaluated in vitro for their antifungal activity against Rhizoctorzia solani, Botrytis cinerea, Alternaria solani, Gibberella zeae, Cucumber anthrax, and Alternaria leaf spot at 100 μg/mL, and some of the designed compounds exhibited potential antifungal activities. Compound 3a (67.9%) exhibited higher activity than the control Osthole (66.1%) against Botrytis cinerea. Furthermore, compound 4b (62.4%) represented equivalent antifungal activity as Osthole (69.5%) against Rhizoctonia solani. The structure-activity relationship (SAR) study demonstrates that linear furanocoumarin moiety has an important effect on the antifungal activity, promoting the idea of the coumarin ring as a framework that might be exploited in the future.

Evaluation of antifungal activities and structure-activity relationships of coumarin derivatives.

Osthol is a natural coumarin and lead compound that has been developed into commercial fungicides in China. Natural coumarins comprise five major subtypes: simple coumarins, linear furanocoumarins, angular furanocoumarins, linear pyranocoumarins and angular pyranocoumarins. Studies pertaining to the antifungal activities of linear pyranocoumarins are few, and no reports exist for the antifungal activities of angular pyranocoumarins. In order to discover more antifungal natural coumarins, we synthesised a series of simple natural coumarins and isolated several plant-based furanocoumarins and pyranocoumarins using previously described methods. The compounds were biologically evaluated against some plant fungal pathogens. Several of the 35 coumarins evaluated here exhibited strong activities against specific fungal species, including compound 25 (Pd-D-V, a linear pyranocoumarin), compound 26 (libanorin, an angular furanocoumarin) and compound 34 (disenecioyl khellactone, an angular pyranocoumarin). Compound 25 exhibited a high activity against Sclerotinia sclerotiorum (EC50 = 13.2 µg mL-1 ); compound 34 displayed a strong antifungal activity against Botrytis cinerea (EC50 = 11.0 µg mL-1 ). This study demonstrates that several natural coumarins (one linear pyranocoumarin and one angular pyranocoumarin in particular) exhibit strong antifungal activities. These results call for further studies, where these coumarins can be examined as potential lead compounds for developing novel antifungal agents. © 2016 Society of Chemical Industry.

ROLE OF INTERMOLECULAR INTERACTIONS IN LINEAR FURANOCOUMARIN DERIVATIVES

Energy calculations have been performed on a series of ten molecules of linear furanocoumarin derivatives to obtain the total stabilization energy i.e. lattice energy of the crystal and also the energy of neighbouring molecular pairs participating in the stabilization of the crystal. The total stabilization energy (lattice energy) lies in the range -16 to -40 kcal mol -1 . Analysis of the energetics of the neighbouring molecular pairs in these structures shows the presence of different intermolecular interactions participating in the crystal packing. In addition to the significance of coulombic nature of bifurcated C-H…O hydrogen bonds, the stabilizing role of π…π stacking interactions has been realized in these structures. A careful observation of energetics of different molecular pairs involving C-H…O hydrogen bond reveals that motifs involving C(sp 2 )-H…O hydrogen bonds are more stabilized than those of C(sp 3 )-H…O.

Elicitation of furanocoumarins in poison hemlock (Conium maculatum L.) cell culture

Furanocoumarins, such as psoralen, xanthotoxin and bergapten, serve as protectants against phytopathogens and are used in pharmaceutical applications e.g. as DNA-crosslinking agents against non-melanoma skin cancers. Poison hemlock plants (Conium maculatum L.) are a known source of furanocoumarins and toxic alkaloids, but systematic research on callus and suspension cultures with the aim of eliciting secondary metabolites is lacking. Therefore callus cultures of poison hemlock were induced with 0.186 mg L−1 6-benzylaminopurine and 2 or 4 mg L−1 naphthalene acetic acid on McCown’s Woody plant medium. A broad variety of elicitors (alginic acid, cellulase, chitosan, ethylene, methyl jasmonate, salicylic acid, copper(II) sulphate and silver nitrate) were tested with an established cell suspension culture for their capacity to trigger differential metabolite accumulation. Samples were extracted and analysed by gas chromatography-mass spectrometry. Elicitation with alginic acid, cellulase, chitosan, silver nitrate and copper(II) sulphate induced furanocoumarins. Plant hormones (ethylene, methyl jasmonate and salicylic acid) were not able to induce furanocoumarins. Extracts contained bergapten, columbianetin, isopimpinellin, marmesin, oroselone, psoralen and xanthotoxin but not piperidine alkaloids. The relative amount of furanocoumarins was generally higher in the medium than in the cells. The report describes the angular furanocoumarins oroselone and columbianetin together with the linear furanocoumarin marmesin, elicited for the first time in poison hemlock.

The investigation on phytochemicals from Ferulago angulata (Schlecht) Boiss, indigenous to central parts of Iran

Ferulago angulata (Schlecht) Boiss (Apiaceae) is a perennial herb distributed in the central parts of Iran. In this work, the essential oil of Ferulago angulat a aerial parts collected from the central parts of Iran was obtained by using hydrodistillation analysed by GC and GC–MS. Air-dried and powdered plant roots were extracted with n-hexane, dichloromethane and methanol, respectively, using a Soxhlet apparatus. The n-hexane extract was subjected to preparative thin-layer chromatography using chloroform–acetone (95:5) as solvent system to yield two linear furanocoumarins, prantschimgin and oxypeucedanin. The structure of theisolated compounds was elucidated by using spectroscopic data such as 1H NMR, 13C NMR, UV and IR. The results of GC–MS analyses showed that γ-terpinolene (11.97%), α-pinene (10.00%), sabinene (6.89%), linalool (5.56%) and cis-ocimene (4.41%) were the main components among 51 constituents characterised in the oil. The oil exhibits considerable phytotoxic activity.

Synthesis and evaluation of linear furanocoumarins as potential anti-breast and anti-prostate cancer agents

A series of 22 furanocoumarin derivatives were synthesized and evaluated for cytotoxicity against breast cancer (MCF-7 and MDA-MB-231) and prostate cancer (PC-3) cell lines along with normal cell line. Several analogs were synthesized by replacing prenyl moiety with alkyl, aromatic, and heteroaromatic functionality to study the structure–activity relationship. Compounds 20 and 22 with adamantoylamino, diprenylamino and substituted benzene sulfonamide substituents showed potent antiproliferative activity in MCF-7 cell line with IC50 values of 0.48 and 0.53 µM, respectively. Both the compounds showed higher IC50 value in MCF-10A cell lines indicating nontoxicity in normal cell lines.

Health threat associated with Caucasian giant hogweeds: awareness among doctors and general public in Poland

Context: The Caucasian giant hogweeds (Heracleum sosnowskyi and H. mantegazzianum) are aggressive invaders successfully spreading across different parts of Europe. Their sap containing linear furanocoumarins can lead to a persisting cutaneous dermatitis and massive skin necrosis.Objective: We aimed to assess the awareness of the giant hogweeds’ threat among physicians and general public in Poland.Methods: The level of awareness was assessed using a short questionnaire given to different groups of physicians: dermatologists (DMs), general practitioners (GPs) and occupational practitioners (OPs). An independent questionnaire was also addressed to the general public.Results: Among the surveyed physician groups, DMs were the best informed, while OPs were the worst informed on health threats associated with the giant hogweeds and treatment methods. Most frequently, application of topical corticosteroids was indicated as a successful method of treatment following the exposure to hogweeds. In the general public, awareness was relatively low with only 57.7% of the surveyed having ever heard about these plants. TV, press and Internet were among the most frequent sources of information in this regard.Conclusions: Public and medical attention needs to be raised as to the threats associated with giant hogweeds, particularly in countries that are highly infested with these plants.

Simultaneous Characterisation of Fifty Coumarins from the Roots ofAngelica dahuricaby Off-line Two-dimensional High-performance Liquid Chromatography Coupled with Electrospray Ionisation Tandem Mass Spectrometry

The root of Angelica dahurica is a traditional Chinese medicine that used for the treatment of headache, toothache, abscess, furunculosis and acne. Coumarins were the major bioactive constituents of A. dahurica, hence it is worthwhile developing a method to simultaneously characterise them, especially those in trace amounts. To develop an efficient method for the simultaneous characterisation of coumarins in A. dahurica. A method using off-line two-dimensional high-performance liquid chromatography coupled with electrospray tandem mass spectrometry (off-line 2D-HPLC-ESI/MS(n) ) was developed. In total 50 coumarins, including 32 linear furanocoumarins, 16 bifuranocoumarins and two non-furanocoumarins, were identified from the roots of A. dahurica. The possible MS fragmentations of these coumarins are also proposed. The method described here allows rapid and convenient identification of the coumarins in A. dahurica, and may be applied to other herbal medicines containing linear furanocoumarins.

Preliminary in vitro and in vivo evaluation of antidiabetic activity of Ducrosia anethifolia Boiss. and its linear furanocoumarins.

Aim. Ducrosia anethifolia is used as flavoring additive. There have been little detailed phytochemical reports on this genus and the antidiabetic activity of this plant is not yet evaluated. Method. Structure of compounds was deduced by spectroscopic analyses. Preliminary in vitro evaluation of the antidiabetic activity of crude extract and its furanocoumarins was carried out (α-amylase, α-glucosidase, and β-galactosidase). The in vivo activity was investigated by measuring some oxidative stress markers. Biomarkers of liver injury and kidney were also determined. Results. Eight linear furanocoumarins, psoralen, 5-methoxypsoralen, 8-methoxypsoralen, imperatorin, isooxypeucedanin, pabulenol, oxypeucedanin methanolate, oxypeucedanin hydrate, and 3-O-glucopyranosyl-β-sitosterol, were isolated. All compounds were reported for the first time from the genus Ducrosia except pabulenol. The blood glucose level, liver function enzymes, total protein, lipid, and cholesterol levels were significantly normalized by extract treatment. The antioxidant markers, glucolytic, and gluconeogenic enzymes were significantly ameliorated and the elevated level of kidney biomarkers in the diabetic groups was restored. The compounds showed inhibitory activity in a concentration dependant manner. Imperatorin and 5-methoxypsoralen showed the most potent inhibiting power. Conclusion. D. anethifolia extract showed hypoglycemic, hypolipidemic, and antioxidant effect as well as ameliorating kidney function. This extract and some linear furanocoumarins exhibited carbohydrate metabolizing enzymes inhibitory effect.

Coumarins and alkaloids in shoot culture of Ruta graveolens L.

A shoot culture of <em>Ruta graveolens</em> L. (<em>Rutaceae</em>) was maintained in the stationary liquid phase. From the cultured shoots seven compounds were isolated and identified as psoralen, bergapten, xanthotoxin, isopimpinellin (linear furanocoumarins), rutamarin (linear dihydrofuranocoumarin), kokusaginine and skimmianine (furanoquinoline alkaloids) by spectral methods. The compounds are known as secondary metabolites of the intact plant, as well as its cell and tissue cultures.

Isolation of furanocoumarins from Pastinaca sativa L. callus culture

Four furanocoumarins: bergapten, xanthotoxin, isopimpinellin (linear furanocoumarins) and sphondin (angular furanocoumarin) were isolated for the first time from callus tissues of <em>Pastinaca sativa</em> L.(<em>Apiaceae</em>) cultured in vitro on solid medium. The compounds were identified using spectral methods. They are well-known secondary metabolites of the intact plant. This is the first report on the isolation of sphondin from in vitro plant cultures.

Structural and optical properties of Heraclenin; A bio-organic molecule from Prangos Pabularia

By column chromatography technique, heraclenin, a linear furano-coumarin with molecular formula C16H14O5 was isolated from the root parts of the plant Prangos pabularia. Various techniques, like X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), optical microscopy (OM), UV–Visible spectroscopy and photoluminescence (PL) were used to study structural and optical properties of the isolated compound. The XRD analysis of the compound predicts its structure to be orthorhombic. The melting point of the compound was found to be 112–114°C. From SEM and optical images, the compound was found to be comprising of large micro crystals and these exhibit irregular surface morphologies. UV–vis spectral studies predicted low absorbance by the compound in the entire visible range. The compound exhibited indirect allowed and forbidden indirect allowed transitions with optical band gap (Eg) around 3.67eV and 3.91eV. PL studies showed good emission in visible region at certain wavelengths. These properties of the compound can be exploited for its application in optoelectronics.

Heraclenin: A Potential Optoelectronic Device Material from Prangos pabularia

Heraclenin (C16H14O5), a linear furanocoumarin, was isolated from the ethyl acetate extract of the roots of Prangos pabularia. The compound was characterized using x-ray diffraction (XRD), scanning electron microscopy (SEM), optical microscopy, ultraviolet (UV)–visible, and photoluminescence (PL) measurements. Structural analysis confirmed the orthorhombic structure of the system. Exploration by SEM and optical images predicted that the compound contains microcrystals with irregular morphology. From UV–visible spectroscopy, high transmission was displayed by these crystals in the entire visible range. The optical band gap (Eg) was found to be around 3.91 eV and exhibited indirect allowed transitions. Photoluminescence data showed good emission at certain wavelengths in the visible region. The observed optical properties could be due to intramolecular charge transfer (ICT) when excited by any suitable light. The present properties of the compound can be explored for use in optoelectronics and as fluorophores in biological imaging applications.

Identification and Quantification of Furanocoumarins in Stem Bark and Wood of Eight Algerian Varieties of Ficus carica by RP-HPLC-DAD and RP-HPLC-DAD-MS

Furanocoumarins are the major phytoalexins of Ficus carica and are effective natural drug candidates for treatment of several types of cancer and skin disease. The objectives of this study were to analyze and quantify linear furanocoumarins, mainly psoralen and bergapten, in wood and bark of stems from eight Algerian varieties of fig and to establish the differences in the content of these metabolites in the eight local samples. Psoralen and bergapten contents in the stem bark and wood (in microg/g DW) varied respectively from 146.6 to 1110.3 and from 395.7 to 1671.8 for psoralen, and from 114.3 to 524.0 and from 144.2 to 718.6 for bergapten. This study fills a gap in our knowledge of furanocoumarin distribution in different parts of the fig tree. Psoralen and bergapten concentrations were higher in the wood than in the stem bark. Most of the dark fruited fig trees produce these two coumarins more than the green ones.

Improved furanocoumarin production in Ruta graveolens L. regenerated via in vitro stem internode cultures

A rapid and efficient in vitro propagation protocol by enhanced multiple shoot proliferation from internode cultures of Ruta graveolens was established. Mean shoot number was maximum (55.83) in Murashige and Skoog (MS) basal medium fortified with 1.0 mg L−1 benzyl amino purine and 0.25 mg L−1 indole-3-acetic acid. The elongated shoots rooted within 10–12 days in 1/2-strength MS medium supplemented with 2.0 mg L−1 indole 3-butyric acid. About 80 % of the rooted plantlets survived acclimatization and transfer to the field. Phytochemical analysis revealed that micropropagated plants produced linear furanocoumarins, characteristic of the species, in greater quantities as compared to the in vivo-grown plants. The results will facilitate the conservation of this valuable medicinal plant and to obtain plants with improved phytochemical constituents.

Studies of the Interaction between Isoimperatorin and Human Serum Albumin by Multispectroscopic Method: Identification of Possible Binding Site of the Compound Using Esterase Activity of the Protein

Isoimperatorin is one of the main components of Prangos ferulacea as a linear furanocoumarin and used as anti-inflammatory, analgesic, antispasmodic, and anticancer drug. Human serum albumin (HSA) is a principal extracellular protein with a high concentration in blood plasma and carrier for many drugs to different molecular targets. Since the carrying of drug by HSA may affect on its structure and action, we decided to investigate the interaction between HSA and isoimperatorin using fluorescence and UV spectroscopy. Fluorescence data indicated that isoimperatorin quenches the intrinsic fluorescence of the HSA via a static mechanism and hydrophobic interaction play the major role in the drug binding. The binding average distance between isoimperatorin and Trp 214 of HSA was estimated on the basis of the theory of Förster energy transfer. Decrease of protein surface hydrophobicity (PSH) was also documented upon isoimperatorin binding. Furthermore, the synchronous fluorescence spectra show that the microenvironment of the tryptophan residues does not have obvious changes. Site marker compettive and fluorescence experiments revealed that the binding of isoimperatorin to HSA occurred at or near site I. Finally, the binding details between isoimperatorin and HSA were further confirmed by molecular docking and esterase activity inhibition studies which revealed that drug was bound at subdomain IIA.

Preventive effect of Imperatorin on acute lung injury induced by lipopolysaccharide in mice

Imperatorin, a linear furanocoumarin, has many pharmacological effects such as antibacterial, anti-inflammatory and antiviral effects. The purpose of this study was to investigate the effect of Imperatorin on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice. BALB/c mice were pretreated with Imperatorin 1h before LPS challenge. We found that the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) in the bronchoalveolar lavage fluid (BALF) were decreased significantly, and the level of interleukin-10 (IL-10) was up-regulated 8h after Imperatorin treatment. Pretreatment with Imperatorin (15 or 30mg/kg) decreased lung wet-to-dry weight (W/D) ratio, the number of inflammatory cells and myeloperoxidase (MPO) activities. Additionally, Imperatorin attenuated lung histopathological changes and significantly inhibited the phosphorylation of IκB, JNK, ERK and p38/MAPK. These findings demonstrate that Imperatorin protects against LPS-induced ALI in mice.

The protective activity of linear furanocoumarins from Angelica dahurica against glucose-mediated protein damage

Advanced glycation end products (AGEs) are known to be directly involved in diabetes mellitus and aging. Therefore, protective activities of isoimperatorin, imperatorin, byakangelicin, and oxypeucedanin hydrate from Angelica dahurica on the formation of AGEs were examined using an in vitro glycation reaction. Isoimperatorin showed strong inhibitory activity against the formation of AGEs. The inhibitory activity of isoimperatorin was more potent than that of the positive control, aminoguanidine. These results suggest that isoimperatorin from A. dahurica may be a promising agent for the treatment of glycation-associated diseases.