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The aim of the present work was to investigate and compare the content of phenolic compounds in four taxa of Erigeron acris L. s. l.: E. acris (EAA), E. acris subsp. droebachiensis (O.F. Müll.) Arcang. (EAD), E. acris subsp. serotinus (Weihe) Greuter (EAS) and E. ×huelsenii Vatke (EH), a hybrid between E. acris and E. canadensis L. The total flavonoid content was determined by Christ-Müller method and the total phenolic acid content was determined by the method utilizing Arnov’s reagent. The method using ultra high performance liquid chromatography with photodiode array detection (UHPLC-PDA) was applied for the separation, identification and quantification of nine phenolic compounds (protocatechuic acid, chlorogenic acid, caffeic acid, 6′-O-caffeoylerigeroside, scutellarein-7-O-β-D-glucuronide, quercetin 3-O-glucoside, 4,5-dicaffeoylquinic acid, quercetin and luteolin) in the aerial parts of E. acris s. l. The chromatographic separation was carried out using a BEH C18 column packed with 1.7-μm particles and gradient elution with a mobile phase of water and methanol, both containing 0.02% (v/v) trifluoroacetic acid. The four investigated taxa of E. acris s. l. differed in the composition and the content of phenolic compounds. The main substances determined in the methanolic herbal extracts were: scutellarein-7-O-β-D-glucuronide (EAA, EAS, EAD and EH), 6′-O-caffeoylerigeroside (EAA, EAD and EH) and chlorogenic acid (EAS and EH). Moreover, the results indicated that five of the nine tested compounds were found in all investigated extracts from herbs of E. acris s. l. Two of them (6′-O-caffeoylerigeroside and scutellarein-7-O-β-D-glucuronide) could be selected as potential chemotaxonomic markers of the genus Erigeron L.

CK2 is a pleiotropic, constitutively active protein kinase responsible for the phosphorylation of more than 300 physiological substrates. Typically, this enzyme is found in tetrameric form consisting of two regulatory subunits CK2β and two catalytic subunits CK2α or CK2α′. Several natural occurring flavonoids were tested for their ability to inhibit both CK2 holoenzymes, CK2α2β2 and CK2α′2β2. We identified few substances selectively inhibiting only the α′ subunit. Other compounds showed similar effect towards all four isoforms. In some cases, like chrysoeriol, pedalitin, apigenin, and luteolin, the α2β2 holoenzyme was at least six times better inhibited than the free α subunit. Otherwise, we have found a luteolin derivative decreased the kinase activity of CK2α′ with an IC50 value of 0.8 μM, but the holoenzyme only with 9.5 µM.

The article presents for the first time the linear temperature programmed retention indices on a column with stationary phases of 5% phenylpolydimethyl silicone and the mass spectra of trimethylsilyl (TMS) derivatives of 71 glycosides (both commercial preparations and compounds extracted from plant tissues) which were not characterized earlier by these parameters. Converted to their TMS derivatives, the glycosides were thermally stable: they exhibited single peaks on their chromatograms without products of thermal decomposition. Therefore this work demonstrates the suitability of high resolution-high temperature gas chromatography (HR-HT/GC) to analyse different groups of glycosides including compounds with disaccharide moieties without the necessity of their hydrolyses. Since a limited number of commercial and plant-isolated glycosides were available, an attempt was made to assess their retention indices using the known "structure-retention relationships" approach. It was demonstrated that the retention indices of silanised glycosides and their aglycones were characterized by a linear dependence.

Introduction The quality of herbs is directly related to the presence of polyphenolic antioxidants. This is the first report on the quantification of individual polyphenolic constituents of Erigeron acris L. Objective To develop a new method using ultra-high performance liquid chromatography with photodiode array and chemiluminescence (UHPLC-PDA-CL) detection for the separation and determination of polyphenols in Erigeron acris extracts. Methodology The methanolic extracts from leaves and inflorescences of Erigeron acris were prepared by ultrasound assisted extraction. The chromatographic separation was performed on C18 column packed with 1.7-μm particles. The post-column CL detection was based on the enhancing effect of polyphenols on the CL generated in manganese(IV)–hexametaphosphate–formaldehyde system. Results The UHPLC method allowed to separate polyphenols in a short running time (13 min), which was three times shorter compared with traditional HPLC. The CL detection was characterised by 6–48 times higher sensitivity and up to three times lower detection limits compared to PDA detection. Qualitative and quantitative differences were observed in polyphenolic composition of Erigeron acris extracts. The main components of leaves were scutellarin and chlorogenic acid, whereas in inflorescences quercetin 3-O-glucoside was predominant. Conclusion Coupling of UHPLC with CL detection has been developed for the first time. This advanced chromatographic technique coupled with sensitive CL detection is a powerful approach for the investigation of polyphenolic profiles in natural products. The shorter analysis time and diminished waste generation makes the UHPLC method more environmentally friendly and more cost-effective in comparison with conventional HPLC. Copyright © 2016 John Wiley & Sons, Ltd.

The mixture of three phytosterols (campesterol, stigmasterol and β-sitosterol), β-sitosterol 3-O-glucoside and syringin were isolated from hexane and methanol extract of Cirsium rivulare roots after chromatographic separation. The main component of the source was syringin which was obtained with the yield 0.08% of the dry source. In hexane extract, the qualitative and quantitative composition of fatty acids was determined. The predominant component was linoleic acid (23.31 mg/g of extract). The extracts showed antioxidant activity. The ability to scavenge DPPH• free radical was in correlation with appointed total phenol content. The not-defatted methanolic extract was the most active. Hexane and defatted methanol extracts showed moderate antibacterial activity against G(+) and G(−) strains with MIC and MBC ranged from 25 to 200 μg/mL.

Viscum album L., the European mistletoe, is a common species from the Viscaceae family. This evergreen hemiparasitic shrub grows on various trees and contains diverse, biologically active substances. Its chemical composition may vary depending on the time of harvest, species of the host tree and the manufacturing process. Among well-described and most active phytochemicals identified in V. album are lectins and viscotoxins, which play substantial role in cancer treatment because of their apoptotic and cytotoxic effects. Another group of compounds found in mistletoe are phenolic acids, phenylpropanoids and flavonoids with antioxidant and anti-inflammatory activities, which decrease blood pressure. Other mistletoe components include, among others, triterpenes with cytotoxic and apoptotic properties, and phytosterols, oligo- and polysaccharides. Extracts from the plant, especially aqueous, are applied in traditional and official medicine, among others in treating hypertension or arthritis. Potentially, it can also be used as a hepatoprotective or a sedative drug.

Ten flavonoids belonging to the subclasses of flavones, flavanones and aurones were isolated from methanolic extract of Cirsium palustre leaves after multistep chromatographic separation. Their structures were elucidated with spectroscopic methods. All compounds, except for luteolin 7-O-glucoside, were isolated for the first time. Four compounds—eriodictyol 7-O-glucoside (6), 6-hydroxyluteolin 7-O-glucoside (11), scutellarein 7-O-glucoside (12) and pedalitin (14)—were tested for their effect on collagen expression in normal human dermal fibroblasts. Among them, compound 11 at 40 μM and compound 14, at all concentrations used (1, 20, 40 μM), significantly enhanced the level of total collagen secreted into the medium. Furthermore, compound 11 significantly stimulated type I collagen expression, whereas compound 14 activated type I and III collagen expression at the mRNA level, depending on concentration. MMP-2 activity was inhibited by all study compounds, with the greatest effect recorded with compound 14 at 20 μM. The lack of effect on collagen content in the medium of compound 6- and compound 12-treated cells, besides an increase in COL1A1 and COL1A2 expression, might be caused by diminished expression of HSP47 gene, resulting in decreased procollagen secretion. Future study of compounds 11 and 14 for their potential therapeutic use in conditions connected with collagen biosynthesis deficiency is required. Copyright © 2014 John Wiley & Sons, Ltd.

CK2 is a ubiquitous protein kinase involved in many cell functions. During the last years it became an interesting target in cancer research. A series of flavonoid compounds was tested as inhibitors of protein kinase CK2. Several substances were found to be highly active against both catalytic subunits with IC 50 values below 1 μM in case of CK2α′. The most promising inhibitor we identified is chrysoeriol with IC 50 values of 250 and 34 nM for CK2α and CK2α′, respectively.

The mechanism underlying the dermatological manifestations that accompany captopril therapy is not known. The facts that prolidase plays an important role in collagen biosynthesis and that captopril directly inhibits prolidase activity led us to evaluate its effect on collagen biosynthesis in cultured human skin fibroblasts. Confluent fibroblasts were treated with milimolar concentrations (0.2-1 mM) of captopril (CAP) for 48 h. It was found that CAP-dependent decrease in prolidase activity was accompanied by parallel decrease in collagen biosynthesis. Since insulin-like growth factor receptor (IGF-IR) is the most potent regulator of both collagen biosynthesis and prolidase activity, and prolidase is regulated by beta1 integrin signaling, the effect of CAP on IGF-IR and beta1 integrin receptor expressions was evaluated. It was found that exposure of the cells to 0.3 mM CAP contributed to a decrease in IGF-IR, alpha2beta1 integrin receptor and MAPK/ERK1/2 expressions. The data suggest that CAP-dependent decrease of collagen biosynthesis in cultured human skin fibroblasts results from inhibition of prolidase activity that may occur through inhibition of alpha2beta1 integrin and IGF-IR signaling.

In this study, antimicrobial properties and toxicity of extracts from Cirsium spp.: Cirsium arvense, C. oleraceum, C. palustre, C. rivulare and C. vulgare in combination with sodium picolinate (PS) or sodium benzoate (BS), were investigated. Three micro-organisms were used: Staphylococcus aureus, Bacillus subtilis and Pseudomonas aeruginosa. Minimum inhibitory concentration (MIC) of extracts was found at 1.56-50.0 mg mL(-1). Unlike the case of BS, adding PS to extracts from flowers of C. palustre and C. arvense enhanced their antimicrobial effect on S. aureus (MIC from 6.25-12.5 mg mL(-1) to 1.25-5.0 mg mL(-1)). An MTT test was used to study toxicity effects. The extracts from C. palustre or C. arvense mixed with PS had a concentration-dependent, slightly cytotoxic or stimulating effect on the viability of normal human skin fibroblasts. The total phenolic content (TPC) of samples varied from 44 to 178 mg gallic acid equivalent per 1 g of extract. The highest TPC was observed in C. palustre (l) and C. oleraceum (f). Our results did not show any correlation between antimicrobial activities and TPC. Cirsium palustre (f) and C. arvense (f) extracts were analysed by gas chromatography/mass spectrometry (GC/MS). About 30 compounds were found to be present in extracts from two Cirsium species in amounts of not less than 0.2% of TIC.

The essential oil from flowers, leaves, stems and roots of Erigeron annuus (L.) Pers. was analyzed by GC, GC-MS and 1H-NMR spectroscopy. More than 60 compounds were identified. Germacrene D (47.2%) and (Z)-lachnophyllum ester (10.2%) were the main constituents of the flower oil. The leaf oil and stem oil contained mainly germacrene D (55.6% and 44.5% respectively) and β-caryophyllene (9.4% and 13.4%), whereas in the root oil dominated matricaria ester (59.9%) and (Z)-lachnophyllum ester (34.9%).

The effects of polyolefinic compound from roots of Cirsium palustre, (Z)-8,9-epoxyheptadeca-1,11,14-triene (EHT) on collagen biosynthesis, prolidase activity, expression of insulin-like growth factor receptor (IGF-IR), β1 integrin, MAP kinases (pERK1/2), the transcription factors such as nuclear factor kappa B (NF-κB) and hypoxia-inducible factor-1α (HIF-1α) were evaluated in human dermal fibroblasts treated with micromolar concentrations (40-200 μM) for 24 h. It was found that EHT-dependent inhibition of collagen biosynthesis was accompanied by parallel inhibition in prolidase activity. Since IGF-I is the most potent regulator of both processes and prolidase is regulated by β1 integrin signalling, the effect of EHT on IGF-IR and β1 integrin receptor expressions were evaluated. Exposure of the cells to EHT contributed to distinct increase in IGF-IR and slight increase in β1 integrin receptor expressions. It was accompanied by decrease in expression of pERK1/2, HIF-1α and NF-κB. EHT-dependent inhibition of collagen biosynthesis results from inhibition of prolidase activity, the enzyme involved in collagen biosynthesis.

We recently reported that, in osteogenesis imperfecta (OI) type I with diminished type I collagen biosynthesis, flavonoids such as apigenin 7-O-glucuronide, apigenin 7-O-methylglucuronide and pectolinarin normalized the level of collagen type I without affecting total protein synthesis. In addition to collagen, glycosaminoglycans (GAGs) play an important role in the formation of a functional supramolecular complex in the extracellular matrix, and any changes in their content and/or composition may be involved in the OI phenotype. We previously detected a marked increase in sulphated GAG content in the OI fibroblasts of more severely affected patients (OI types II and III). These alterations were more pronounced in medium than in cells. Although, in OI type I cells, the increase observed in medium was much smaller (approximately 1.5-fold), it resulted in an increase of approximately 3-fold of the GAG to collagen type I ratio. Therefore, in the potential pharmacotherapy of OI type I with flavonoids, their effect on GAG level may be of importance. In the OI cells, some of the tested flavonoids applied at a concentration of 30 µM affected GAG content in quite the opposite way than type I collagen. Aglicones inhibiting collagen synthesis caused a marked increase in GAG concentration in medium, in contrast to the flavonoid glycosides, which exerted a stimulatory effect on type I collagen synthesis, but had a different effect on GAG content and distribution. Among these, apigenin 7-O-methylglucuronide did not affect GAG level or secretion, and thus may potentially be used in OI type I pharmacotherapy in patients with normal GAG content. However, in patients with increased concentrations of GAG, pectolinarin, which decreases GAG content by approximately 40%, may be more beneficial.

Crude aqueous extracts from leaves of Cirsium arvense, C. oleraceum, C. palustre, C. rivulare and C. vulgare were investigated. The content of tannins in mentioned sources, determined by the weight method with hide powder, varied between 1 and 7.63%. Total phenolic content, analysed by using Folin-Ciocalteau's method, ranged between 54 and 96 mg g(-1), was expressed as milligrams of gallic acid per gram of dry extract. Phenolic acids were identified by HPLC method. Antimicrobial activity of those extracts was examined. Cirsium palustre extract was the most active against investigated microorganisms. It was observed that the content of small-molecular phenolic compounds had greater influence on the activity of extracts than tannins. The total antioxidant activity indicated by radical cation 2,2'-azini-di-(3-ethylbenzthiazoline sulphonate) ABTS(*+), expressed as total antioxidant status (TAS) ranged from 2.31 to 2.78 mM L(-1).

The aim of the present study was to identify bioactive compounds stimulating collagen biosynthesis with potential for osteogenesis imperfecta (OI) type I pharmacological therapy. Of the compounds tested, apigenin glycosides 7-O-glucuronide, 7-O-methylglucuronide and pectolinarin at 30 microM were found to significantly induce collagen type I synthesis in OI fibroblasts without an effect on the overall protein synthesis. None of the compounds displayed any toxicity at that concentration. Secretion of collagen into media was not affected by apigenin 7-O-glucuronide and was slightly increased in cells treated with apigenin 7-O-methylglucuronide and pectolinarin. Furthermore, procollagen secreted by treated cells underwent a more rapid processing into collagen as compared with control untreated cells. In addition, we elucidated the possible mechanism involved in their action. Stimulation of collagen biosynthesis was not due to an increase in cell proliferation, because no differences in DNA content between the compound-treated and untreated cells were observed. Since flavonoids are known as strong inhibitors of metalloproteinases degrading matrix proteins, the increased level of collagen could result from the inhibition of their activity. However, the compounds with a stimulatory effect on collagen synthesis did not influence the activities of collagenase type I, gelatinases A and B, and stromelysin. On the contrary, all compounds stimulated the activity of prolidase which catalyzes the final step of collagen degradation and plays an important role in collagen biosynthesis. Stimulation of collagen synthesis and prolidase activity by apigenin 7-O-glucuronide was accompanied by an increase in IGF-I receptor expression. In contrast, the compounds apigenin 7-O-methylglucuronide and pectolinarin which normalized collagen synthesis in OI cells may exert their effects through beta1-integrin-mediated signaling.

The collagen metabolism alterations triggered by reactive oxygen species are involved in the development of various connective tissue diseases and skin aging. This study was designed to examine whether (E)-anethole possesses a protective effect on H2O2-induced alterations in collagen metabolism as well as whether it can prevent apoptosis in human skin fibroblasts. In cells treated with 300 µM H2O2, a decrease in collagen biosynthesis of 54 % was observed. Pretreatment of cells with 0.5 µM anethole for 1 h completely prevented this alteration. Changes at the protein level positively correlated with alterations of type I collagen mRNA expression. We have shown that H2O2 caused increase in the activity of MMP-2 and MMP-9 as well as that an increase in MMP-2 activity can contribute to the 8 % decrease in the amount of collagen secreted into the medium. The most efficient suppression of these changes was observed in the presence of 0.5 µM of anethole. At 10 µM, in addition to suppression, an inhibitory effect of anethole on MMP-9 activity was documented. Additionally, the 60 % H2O2-induced decrease in cell viability was suppressed by 1 µM of anethole and a 4-fold increase in cell apoptosis was suppressed by 0.5 µM of anethole. Our results suggest that anethole, which is a small lipophilic and non-toxic molecule with the ability to prevent H2O2-induced collagen metabolism alterations and apoptosis in human skin fibroblasts, would prove useful in the development of effective agents in pharmacotherapy of oxidative stress-related skin diseases.