Decreased activity of neutrophils in the presence of diferuloylmethane (curcumin) involves protein kinase C inhibition

Diferuloylmethane (curcumin) has been shown to act beneficially in arthritis, particularly through downregulated expression of proinflammatory cytokines and collagenase as well as through the modulated activities of T lymphocytes and macrophages. In this study its impact on activated neutrophils was investigated both in vitro and in experimental arthritis. Formation of reactive oxygen species in neutrophils was recorded on the basis of luminol- or isoluminol-enhanced chemiluminescence. Phosphorylation of neutrophil protein kinases C alpha and beta II was assessed by Western blotting, using phosphospecific antibodies. Adjuvant arthritis was induced in Lewis rats by heat-killed Mycobacterium butyricum. Diferuloylmethane or methotrexate was administered over a period of 28 days after arthritis induction. Under in vitro conditions, diferuloylmethane (1-100 microM) reduced dose-dependently oxidant formation both at extra- and intracellular level and it effectively reduced protein kinase C activation. Adjuvant arthritis was accompanied by an increased number of neutrophils in blood and by a more pronounced spontaneous as well as PMA (phorbol myristate acetate) stimulated chemiluminescence. Whereas the arthritis-related alterations in neutrophil count and in spontaneous chemiluminescence were not modified by diferuloylmethane, the increased reactivity of neutrophils to PMA was less evident in diferuloylmethane-treated animals. The effects of diferuloylmethane were comparable with those of methotrexate. Diferuloylmethane was found to be a potent inhibitor of neutrophil functions both in vitro and in experimental arthritis. As neutrophils are considered to be cells with the greatest capacity to inflict damage within diseased joints, the observed effects could represent a further mechanism involved in the antirheumatic activity of diferuloylmethane.

[Antilipoxygenase activity and the trace elements content of Aloe vera in relation to the therapeutical effect]

Aloe vera is a rich source of many natural-health-promoting substances. The results of contemporary research on animal models indicate that the extracts have an antiinflammatory property. In this work the results of some in vitro experiments are shown: determination of the inhibitory effect of the Aloe vera extracts on the activity of partially purified lipoxygenase from the rat lung cytosol fraction, and quantitative determination of the trace elements presented in the extract (Mn, Fe, Cu, Zn) carried out by using the x-ray fluorescence analysis. The findings could explain the inhibitory effect (antilipoxygenase activity) of the Aloe vera extract in the acute inflammation process, expecially in the topical application for healing of minor burns and skin ulcers.

[Isolation and characterization of active compounds from Aloe vera with a possible role in skin protection]

Aloe vera is widely used in food supplements, beverages, pharmaceuticals, and cosmetics. It has been long recognized as an effective natural remedy for its wound-healing properties and its positive influence on other inflammatory skin disorders. Major proteins and mono- and polysaccharides were identified and analysed from Aloe vera commercial extract. Molecular weight of proteins calculated from the sets of molecular weight reference standards, ranged from 70 kDa for the largest to 14 kDa for the smallest ones. IR spectral analysis of the carbohydrate fraction shows that the main carbohydrate copound is acetylated (1 --> 4)-beta-D-mannan substituated with D-galactose and D-glucose. The results have shown that proteins and polysaccharides are a necessary component in the study of biological activity of Aloe vera leaf extract.

Isoquinoline alkaloids from Mahonia aquifolium stem bark are active against Malassezia spp

Bioassay directed fractionation of crude extract from Mahonia aquifolium led to the isolation of fraction A (bisbenzylisoquinoline alkaloid complex, BBI) and a fraction of protoberberine alkaloids, where the major compounds berberine and jatrorrhizine were isolated as their iodides. The antifungal activity of the crude extract, two protoberberine alkaloids and BBI from M. aquifolium stem bark were evaluated against six strains of Malassezia spp. The compounds tested were generally found to possess only weak to moderate antifungal properties: the MICs for individual strains were in the range < or = 50-> or = 1000 mg/L.

Antimicrobial activity of berberine--a constituent of Mahonia aquifolium

The antimicrobial activity of the protoberberine alkaloid, berberine, isolated from Mahonia aquifolium, was evaluated against 17 microorganisms including two Gram-negative bacteria--Pseudomonas aeruginosa and Escherichia coli (both resistant and sensitive), two Gram-positive bacteria--Bacillus subtilis and Staphylococcus aureus, Zoogloea ramigera, six filamentous fungi--Penicilium chrysogenum, Aspergillus niger, Aureobasidium pullulans (black and white strain), Trichoderma viride (original green strain and brown mutant), Fusarium nivale, Mycrosporum gypseum and two yeasts--Candida albicans and Saccharomyces cerevisiae. The IC50, minimum inhibitory concentration (MIC), minimum microbicidal concentration (MMC) and minimum microbistatic concentration (MMS) varied considerably depending on the microorganism tested, the sensitivity decreasing as follows: S. aureus > P. aeruginosa S (sensitive) > E. coli S > P. aeruginosa R (resistant) > E. coli R > B. subtilis > Z. ramigera > C. albicans > S. cerevisiae > A. pullulans B (black) > A. pullulans W (white) > T. viride Br (brown) > M. gypseum > A. niger > F. nivale > P. chrysogenum > T. viride G (green).

[Anticomplement activity of Mahonia aquifolium bisbenzylisoquinoline alkaloids and berberine extract]

Crude extracts obtained from the stem bark of Mahonia aquifolium have been investigated as to the chemical composition and anticomplementary activity. The results show that their anticomplementary activity is mainly due to the alkaloid components. Especially the BBI alkaloid fraction and berberine showed a strong inhibitory effect on CH50 total hemolytic complement assay. The crude extract of M. aquifolium was less active than berberine or the fraction BBI alkaloids. The results indicate that the fraction of BBI alkaloids and berberine largely account for the immunomodulatory activity of the crude extract of M. aquifolium.

[Polyphenol compounds from Hamamelis virginiana L]

Two phenolic acids and two flavone aglycones were isolated from the aboveground part of Hamamelis virginiana L. and identified with the use of thin-layer chromatography, melting points, and spectroscopic methods as gallic acid, ethyl gallate, quercetin, and kaempferol.

[Herbal polysaccharides in the treatment of coughs]

BACKGROUND

Because of serious adverse effects of centrally acting antitussive agents, is necessary to find new drugs with cough-suppressing activity. Medicinal herbs are a potential source of polysaccharides with high antitussive efficiency and on the other with minimal side effects.

AIM

The study was to assess the antitussive action of mixture of a polysaccharides (RL) and polysaccharide-xylan (XY), both isolated from above-ground parts of Rudbeckie fulgida var. sullivantii. The observed activity was compared to those of narcotic and nonnarcotic antitussive substances used in clinical practice.

METHODS

Cough was evoked by mechanical irritation of the airways in nonanaesthetized cats with chronic tracheal cannuly. The plant substances were administered perorally in the dose of 50 mg per kg body weight.

RESULTS

Results indicate, that administration of RL induced a suppression of the followed cough parameters from both areas of airways (total fall in cough parameters by 46.6%). Administration of xylan induced the fall in the followed cough parameters with more significant influence on the laryngopharyngeal area of the airways (total fall in cough parameters 48.2%).

CONCLUSION

Administration of RL and xylan did not achieve the effect of codeine, but had a more intensive antitussive effect than the peripherally acting droprozine and prenoxdiazine. (Fig. 3, Ref. 11.)

Relaxant properties of some aporphine alkaloids from Mahonia aquifolium

In the present study we tested the effect of four aporphine alkaloids, corytuberine, magnoflorine, isothebaine and isocorydine, on the isolated rat aorta. Corytuberine and magnoflorine showed little effect as relaxants in KCl- and noradrenaline-induced contractions. They did not inhibit the phenylephrine concentration-response curve (CRC). Isothebaine and isocorydine showed relaxant properties in the rat aorta. They relaxed the contractions induced by noradrenaline to a greater extent than those induced by KCl and they also inhibited the noradrenaline-induced contraction in calcium-free solution. These alkaloids competitively shifted the phenylephrine CRC to the right and non-competitively the serotonin CRC. They seemed to inhibit both the influx of calcium into the cell, preferentially through receptor-regulated calcium channels, and the release of calcium from intracellular stores. Moreover, they appear to be antagonists of alpha 1-adrenoceptors. Study of structure-activity relationships of aporphine alkaloids in the inhibition of calcium influx via potential-operated Ca2+ channels yielded information indicative of the interaction of these substances with the benzothiazepine receptor.

Lipoxygenase inhibition and antioxidant properties of bisbenzylisoqunoline alkaloids isolated from Mahonia aquifolium

Products of lipoxygenase metabolism are known to play a role in the pathogenesis of psoriasis. Six bisbenzylisoquinoline (BBIQ) alkaloids, oxyacanthine, armoline, baluchistine, berbamine, obamegine, aquifoline, isolated from Mahonia aquifolium, were tested for lipoxygenase inhibition. Berbamine and oxyacanthine were the most potent lipoxygenase inhibitors, whereas aromoline and baluchistine exhibited only very low potencies. Oxyacanthine and berbamine were also among the most active compounds to inhibit lipid peroxidation. Between the results of lipoxygenase inhibition and the lipid peroxidation a linear correlation was found (r = 0.9533). Our data suggest that in the mechanism of lipoxygenase inhibition by these alkaloids, inhibition of lipid peroxide substrate accumulation, either by direct reaction with peroxide or by scavenging or lipid-derived radicals, may play a role. Inhibition of lipoxygenase by these compounds may contribute to the therapeutic effect of Mahonia aquifolium extracts in treatment of diseases in pathogenesis of which he products of lipoxygenase metabolism are involved.

Lipoxygenase inhibition and antioxidant properties of protoberberine and aporphine alkaloids isolated from Mahonia aquifolium

Products of lipoxygenase metabolism play a role in the pathogenesis of psoriasis. Four protoberberine alkaloids, berberine, oxyberberine, jatrorrhizine, columbamine, and two aporphine alkaloids, magnoflorine, and corytuberine, isolated from Mahonia aquifolium, were tested for lipoxygenase inhibition. Oxyberberine, corytuberine, and columbamine were the most potent lipoxygenase inhibitors tested, whereas berberine and magnoflorine exhibited only low potencies. A strong linear correlation (r = 0.866) between lipoxygenase inhibition and lipid antioxidant properties of these compounds was found. These data suggest that the mechanism of lipoxygenase inhibition by these alkaloids may be linked to the inhibition of lipid hydroperoxide substrate accumulation. Inhibition of lipoxygenase by these compounds may contribute to the therapeutic effect of M. aquifolium extracts in the treatment of psoriasis.

[Testing for immunomodulating effects of ethanol-water extracts of the above-ground parts of the plants Echinaceae (Moench) and Rudbeckia L]

Ethanolic extracts of aerial parts of the plants Echinacea angustifolia DC, Echinacea purpurea L. (Moench), Rudbeckia fulgida var. sullivantii, Boyton et Beadle, and Rudbeckia speciosa Wenderoth show immunomodulating activity. The mice were treated in vivo for 5 days and the activity was tested for and observed on day 7. An immunostimulatory effect was observed on the phagocytic, metabolic and bactericidal activities of peritoneal macrophages. The ethanolic extracts of both Echinacea plants also increased the total weight of the spleens as compared to the effect of the Rudbeckia plants and the control group which received saline.

[Immunomodulating activity of ethanol-water extracts of the roots of Echinacea gloriosa L., Echinacea angustifolia DC. and Rudbeckia speciosa Wenderoth tested on the immune system in C57BL6 inbred mice]

The ethanolic extract from the roots Echinacea gloriosa L. (Moench), Echinacea angustifolia DC. and Rudbeckia speciosa Wenderoth shows immunomodulating activity. It was seen on the seventh day after five days of in vivo treatment of mice. The most marked immunostimulatory effect was observed on the lysosomal and peroxidal activity of peritoneal macrophages, and splenic cells after in vivo treatment with the ethanolic extract of the roots of R. speciosa Wenderoth.