Immunomodulatory and anti-inflammatory activity of selected osthole derivatives.

From osthole [7-methoxy-8-(3-methyl-but-2-enyl)-chromen-2-one] (I), obtained by selective extraction of Peucedanum ostruthium (L.) W. Koch roots, ostholic acid (II) was synthetized as a result of its oxidation with chromium trioxide. From ostholic acid, through its chloride, four amides were obtained: the morpholide 1, the p-chloro-benzylamide 2, the piperidine 3 and the N-methyl-piperazide 4. Except for 1, other compounds have not been described before. The amides 1-4 and their precursor osthole (I) were tested for their potential activities in selected immunological assays. The compounds showed moderate inhibitory activity in the humoral immune response to sheep erythrocytes in mice in vitro, and 4 was the most suppressive. The effects of 1 and 3 on concanavalin A- and pokeweed mitogen-induced mouse splenocyte proliferation were inhibitory and those of 4 stimulatory. The compounds were also tested for their activity on tumour necrosis factor a and interleukin 6 production, induced by lipopolysaccharide, in cultures of rat peritoneal cells and human peripheral blood mononuclear cells. Compounds 1, 3 and 4 inhibited tumour necrosis factor a (rat cells), whereas compound 2 stimulated the production of both cytokines. Compounds 1, 2 and 3 were also strongly inhibitory on tumour necrosis factor a production in human blood cells (73, 78 and 80% inhibition at 10 microg/ml, respectively). On the other hand, 2 and 4 stimulated the interleukin 6 production (2- to 3-fold stimulation). In addition, 2 and 4 suppressed the carrageenan-induced inflammation in mice (56.5% and 68.3% inhibition, respectively). In summary, the compounds predominantly displayed suppressive and antiinflammatory activities in the investigated models.

Anticonvulsant and acute neurotoxic effects of imperatorin, osthole and valproate in the maximal electroshock seizure and chimney tests in mice: a comparative study.

The aim of this study was to determine and compare the anticonvulsant and acute adverse (neurotoxic) effects of imperatorin and osthole (two natural coumarin derivatives) with valproate (a classical antiepileptic drug) in the maximal electroshock seizure and chimney tests in mice. The anticonvulsant and acute adverse effects of imperatorin, osthole and valproate were determined at 15, 30, 60 and 120 min after their systemic (i.p.) administration. The evaluation of time-course and dose-response relationships for imperatorin, osthole and valproate in the maximal electroshock seizure test revealed that the compounds produced a clear-cut antielectroshock action in mice and the experimentally derived ED(50) values for imperatorin ranged between 167 and 290 mg/kg, those for osthole ranged from 253 to 639 mg/kg, whereas the ED(50) values for valproate ranged from 189 to 255 mg/kg. The evaluation of acute neurotoxic effects in the chimney test revealed that the TD(50) values for imperatorin ranged between 329 and 443 mg/kg, the TD(50) values for osthole ranged from 531 to 648 mg/kg, while the TD(50) values for valproate ranged from 363 to 512 mg/kg. The protective index (as a ratio of TD(50) and ED(50) values) for imperatorin ranged between 1.13 and 2.60, for osthole ranged from 0.83 to 2.44, and for valproate ranged between 1.72 and 2.00. In conclusion, both natural coumarin derivatives deserve more attention from a preclinical point of view as compounds possessing some potentially favorable activities in terms of suppression of seizures, quite similar to those reported for valproate.

Osthole suppresses seizures in the mouse maximal electroshock seizure model.

The aim of this study was to determine the anticonvulsant effects of osthole {[7-methoxy-8-(3-methyl-2-butenyl)-2H-1-benzopyran-2-one]--a natural coumarin derivative} in the mouse maximal electroshock-induced seizure model. The antiseizure effects of osthole were determined at 15, 30, 60, and 120 min after its systemic (i.p.) administration. Time course of anticonvulsant action of osthole revealed that the natural coumarin derivative produced a clear-cut antielectroshock activity in mice and the experimentally-derived ED(50) values for osthole ranged from 259 to 631 mg/kg. In conclusion, osthole suppresses seizure activity in the mouse maximal electroshock-induced seizure model. It may become a novel treatment option following further investigation in other animal models of epilepsy and preclinical studies.

Free and chemically bonded phenolic acids in barks of Viburnum opulus L. and Sambucus nigra L.

Liquid column chromatography, planar chromatography (TLC) on modified and unmodified silica layers, reversed-phase high-pressure liquid chromatography (HPLC), as well as ESI-TOF MS and 1H-NMR have been used for separation, purification and identification of phenolic acids in the barks of Sambucus nigra and Viburnum opulus (Caprifoliaceae). By the use of these procedures three cinnamic acid derivatives: caffeic acid, p-coumaric, and ferulic acid, four benzoic acid derivatives: gallic acid, protocatechuic acid, syringic acid, 3,4,5-trimethoxybenzoic acid, two phenylacetic acid derivatives: 3,4-dihydroxyphenylacetic acid, homogentisic acid, and two depsides: chlorogenic acid and ellagic acid were detected and identified in the bark of Viburnum opulus. Caffeic acid, p-coumaric acid, ferulic acid, gallic acid, syringic acid, 3,4,5-trimethoxybenzoic acid and chlorogenic acid were also detected and identified in the bark of Sambucus nigra. Except for chlorogenic acid, this is the first time these phenolic acids have been isolated, detected, and identified in the bark of V. opulus and S. nigra.

The influence of auxins on the biosynthesis of isoprene derivatives in callus cultures of Vaccinium corymbosum var. bluecrop.

Callus cultures of Vaccinium corymbosum var. bluecrop were optimized for their isoprene derivatives production by supplementing Schenk-Hildebrandt (SH) medium with constant concentration of kinetin (2.32 microM) and two different amounts of selected auxins. Every auxin, except for IBA, used in 10-time higher concentration (2,4D, NAA, IAA, NOA) stimulated biosynthesis of beta-sitosterol and inhibited triterpene synthesis. Quantitative analysis of isoprene derivatives in callus biomass collected on the 25th day of the experiment proved that the analyzed callus of Vaccinium corymbosum var. bluecrop synthesized the highest amount of isoprene derivatives after subculturing on SH medium modified with 22.6 microM of 2,4D and 2.32 microM of kinetin.

Binding of an oxindole alkaloid from Uncaria tomentosa to amyloid protein (Abeta1-40).

The primary aim of this work was to determine the interactions of an oxindole alkaloid (mitraphylline) isolated from Uncaria tomentosa with beta-amyloid 1-40 (Abeta1-40 protein) applying the capillary electrophoresis (CE) method. Specifically the Hummel-Dreyer method and Scatchard analysis were performed to study the binding of oxindole alkaloids with Abeta1-40 protein. Prior to these studies extraction of the alkaloid of interest was carried out. Identification of the isolated alkaloid was performed by the use of thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) combined with electrospray ionization mass spectrometry (ESI-MS). The proposed approach was proved to be an efficient and accurate method for specific compound isolation and identification purposes. Moreover, analytical information from the CE approach can be considered as the valuable tool for binding constant determination. The binding constant of mitraphylline with Abeta1-40 protein determined by the Hummel-Dreyer method and Scatchard analysis equals K = 9.95 x 10(5) M(-1). The results obtained showed the significant binding of the tested compound with Abeta1-40 protein. These results are discussed and interpreted in the view of developing a strategy for identification of novel compounds of great importance in Alzheimer disease therapy.

Isoprene derivatives from the leaves and callus cultures of Vaccinium corymbosum var. bluecrop.

The phytochemical analysis of Vaccinium corymbosum var bluecrop leaves and callus biomass revealed ursolic acid, oleanolic acid, alpha-amyrin and beta-amyrin in both plant materials. Beta-sitosterol was determined only in callus biomass. The structure of isolated compounds was elucidated by TLC co-chromatography with standards and with spectroscopic methods (1H NMR, 13C NMR, EI-MS).

[Low-molecular antioxidant compounds of natural origin]. / Niskoczasteczkowe zwiazki przeciwutleniajace pochodzenia naturalnego.

Vitamins C, and E, carotenoids, and phenolic compounds from plants are low-molecular substances which express strong antioxidant and antiradical activity. Free radical processes are very complicated way, and it is impossible to draw conclusions from in vitro analysis of any compound regarding the role it would play under in vivo conditions. In this study, the in vivo and in vitro antioxidant and antiradical activities of some antioxidants contained in vegetable foods as well as the possibility of their prooxidant activity are described.

Investigation of the essential oils from three Cephalotaxus species.

Essential oils from leaves of Cephalotaxus fortunei Hook., Cephalotaxus haningtonia K. Koch., Cephalotaxus sinensis Li. and variety Cephalotaxus harringtonia var. drupacea Koidz. underwent qualitative and quantitative analysis. The content of the oils obtained by hydrodistillation in the investigated species was 0.01 - 0.22% v/w. Gas chromatography (GC-MS) with flame ionisation detector (FID) showed generally 47 components in the essential oils. In all investigated species the presence of a-pinene varying from 18.4% to 35.1%, as well as sesquiterpene hydrocarbon beta-caryophyllene up to 22% at Cephalotaxus fortunei were revealed as the main components.

Antiradical and anti-H2O2 properties of polyphenolic compounds from an aqueous peppermint extract.

Polyphenolic compounds such as eriocitrin, luteolin-7-O-rutinoside, diosmin, hesperidin, narirutin, isorhoifolin, rosmarinic and caffeic acids were identified in an aqueous extract (Ex) obtained from peppermint leaves (Menthae x piperitae folium). The content of polyphenols in Ex was as follows: eriocitrin 38%, luteolin-7-O-rutinoside 3.5%, hesperidin 2.9%, diosmin 0.8%, isorhoifolin 0.6%, narirutin 0.3%, rosmarinic acid 3.7% and caffeic acid 0.05%. The strongest antiradical activity (determined as DPPH* scavenging features) was observed for luteolin-7-O-rutinoside, eriocitrin and rosmarinic acid. Caffeic acid and hesperidin revealed a lower antiradical activity while isorhoifolin, narirutin and diosmin showed the lowest activity. The strongest anti-H2O2 activity was observed for eriocitrin, a little lower for rosmarinic acid. The rate of hydrogen peroxide scavenging activity displayed by luteolin-7-O-rutinoside and caffeic acid was lower than that of rosmarinic acids. Hesperidin appeared to be a very weak scavenger of hydrogen peroxide. Almost no anti-H2O2 activity was demonstrated for diosmin, narirutin and isorhoifolin. Among examined flavonoids, the strongest antiradical and anti-H2O2 activity was shown for compounds with two hydroxy groups bound to the Bring in ortho position in relation to each other. Replacement of one hydroxy group in the Bring with a methoxy group or removing one hydroxy group leads to decrease of antiradical and anti-H2O2 activity of flavonoids. Our results suggest that eriocitrin is a powerful peppermint antioxidant and a free radical scavenger.

Polyphenolic compounds from Platycodon grandiflorum A. DC.

Flavonoids and phenolic acids from the aerial parts of Platycodon grandiflorum A. DC. were analysed by isocratic TLC, MGD-TLC and HPLC methods. Four flavonoid compounds were determined including luteolin 7-O-glucoside as the main component and apigenin 7-O-glucoside, luteolin and apigenin. When performing HPLC analysis, 12 phenolic acids in the free, depside and glycoside forms were identified. Among them, 3,4-dimethoxycinnamic, caffeic, chlorogenic, ferulic, isoferulic, homovanillic, alpha-resorcylic, m-coumaric, p-coumaric, p-hydroxybenzoic, 2-hydroxy-4-methoxybenzoic and 2,3-dihydroxybenzoic acids.

Antioxidant capacity manipulation in transgenic potato tuber by changes in phenolic compounds content.

The main goal of this study was to generate potato tubers with increased levels of flavonoids and thus modified antioxidant capacities. To accomplish this, the vector carrying multigene construct was prepared and several transgenic plants were generated, all overexpressing key biosynthesis pathway enzymes. The single-gene overexpression or simultaneous expression of genes encoding chalcone synthase (CHS), chalcone isomerase (CHI), and dihydroflavonol reductase (DFR) resulted in a significant increase of measured phenolic acids and anthocyanins. The increase in phenolic compounds synthesis is accompanied by decreases in starch and glucose levels in transgenic plants. The flavonoids-enriched plants showed improved antioxidant capacity; however, there is a complex relationship between antioxidant capacity and flavonoids content, suggesting the great participation of other compounds in the antioxidant potential of the plants. These other compounds are not yet recognized.

Antiradical activity of hydrolyzed and non-hydrolyzed extracts from Helichrysi inflorescentia and its phenolic contents.

A methanol extract was obtained from defatted (petroleum ether) inflorescence of Helichrysum arenarium (L.) Moench (perennial herb native to Middle and Southeast Europe). The extract was evaporated under reduced pressure and the dry residue was dissolved in hot water. The aqueous solution was stored for 6 d at 4 degrees C and the precipitate discarded. The remaining solution was divided into three aliquots a, b and c. Part a was extracted with ethyl acetate to obtain extract (A), part b was extracted with diethyl ether to obtain extract (B) and part c was subjected to alkaline hydrolysis and then extracted with diethyl ether to obtain extract (C). Extracts (A), (B) and (C) were evaporated under reduced pressure to obtain the dry residues A, B and C which were further investigated for phenolic compound content by TLC and HPLC and for antiradical activity with 2,2-diphenyl-1-picrylhydrazyl radical (DPPH*) as a substrate. Residue C exhibited stronger antiradical properties than non-hydrolysed residues A and B. HPLC analysis showed a great increase of caffeic acid in residue C. We concluded that the hydrolysis process led to a significant increase of free caffeic acid (strong antioxidant) concentration resulting in increased antiradical activity of residue C.

Comparative analysis of the composition of the volatile oils of two forms of Achillea crithmifolia W. et. K.--diploid and tetraploid.

The genus Achillea L. includes more than 100 species and is a polyploid complex of di-, tetra-, hexa- and octaploids, individuals.