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1.
Phytomedicine ; 8(1): 28-30, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11292236

RESUMO

Harpagophytum procumbens (Devil's Claw) is often used in the supportive treatment of inflammatory and degenerative diseases of the skeletal system. Here we studied the anti-inflammatory properties of the Harpagophytum extract SteiHap 69 (Steiner Harpagophytum procumbens extract 69) on primary human monocytes, a useful model of peripheral inflammation. After eliminating lipopolysaccharides of bacterial origin, SteiHap 69 prevented the LPS-induced synthesis of tumour necrosis factor alpha (TNFalpha) in stimulated primary human monocytes in a dose-dependent manner. Harpagide and harpagoside had no effect on LPS-induced TNFalpha-release. Our data provides evidence that the Harpagophytum extract SteiHap 69 has anti-inflammatory properties. Further studies are required in order to elucidate the molecular mechanism of Devil's claw anti-inflammatory effects.


Assuntos
Anti-Inflamatórios/farmacologia , Magnoliopsida , Monócitos/efeitos dos fármacos , Plantas Medicinais , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Lipopolissacarídeos , Extratos Vegetais/farmacologia
2.
BMJ ; 319(7224): 1534-8, 1999 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-10591711

RESUMO

OBJECTIVES: To assess the efficacy and safety of hypericum extract (STEI 300, Steiner Arzneimittel, Berlin) compared with imipramine and placebo in patients in primary care with a current episode of moderate depression. DESIGN: Randomised, double blind, multicentre, parallel group trial for 8 weeks. SETTING: Trained panel of 18 general practitioners from four German states: Bavaria, Berlin, Rhineland Palatinate, and Saxony. PARTICIPANTS: 263 patients (66 men, 197 women) with moderate depression according to ICD-10 (international classification of diseases, 10th revision) codes F32. 1 and F33.1. INTERVENTIONS: 1050 mg hypericum extract (350 mg three times daily), 100 mg imipramine (50 mg, 25 mg, and 25 mg daily), or placebo three times daily. MAIN OUTCOME MEASURES: Change from baseline score on the 17 item version of the Hamilton depression scale, the Hamilton anxiety scale, the clinical global impressions scale, Zung's self rating depression scale, and SF-36, and adverse events profile. RESULTS: Hypericum extract was more effective at reducing Hamilton depression scores than placebo and as effective as imipramine (mean -15.4 (SD 8.1), -12.1 (7.4), and -14.2 (7.3) respectively). Comparable results were found for Hamilton anxiety and clinical global impressions scales and were most pronounced for the Zung self rating depression scale. Quality of life was more improved in the standardised mental component scale of the SF-36 with both active treatments than with placebo but in the physical component scale was improved only by hypericum extract compared with placebo. The rate of adverse events with hypericum extract was in the range of the placebo group but lower than that of the imipramine group (0.5, 0.6, and 1.2 events per patient respectively). CONCLUSIONS: At an average dose of 350 mg three times daily hypericum extract was more effective than placebo and at least as effective as 100 mg imipramine daily in the treatment of moderate depression. Treatment with hypericum extract is safe and improves quality of life.


Assuntos
Antidepressivos Tricíclicos/uso terapêutico , Transtorno Depressivo/tratamento farmacológico , Hypericum/uso terapêutico , Imipramina/uso terapêutico , Fitoterapia , Plantas Medicinais , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Qualidade de Vida , Resultado do Tratamento
3.
Planta Med ; 64(8): 758-60, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9933996

RESUMO

Two ethanolic dry extracts from the herb Chelidonium majus L. with a defined content of the main alkaloids (chelidonine, protopine, and coptisisine) and the alkaloids themselves were studied in three different antispasmodic test models on isolated ileum of guinea-pigs. In the BaCl2-stimulated ileum, chelidonine and protopine exhibited the known papaverine-like musculotropic action, whereas coptisine (up to 3.0 x 10(-5) g/ml) was ineffective in this model. Both extracts were active with 53.5% and 49.0% relaxation at 5 x 10(-4) g/ml. The carbachol and the electric field stimulated contractions were antagonized by all three alkaloids. Coptisine showed competitive antagonist behaviour with a pA2 value of 5.95. Chelidonine and protopine exhibited a certain degree of non-competitive antagonism. In the electric field the antagonist activities decreased in the order protopine > coptisine > chelidonine. The concentrations of the chelidonium herb extracts for 50% inhibition of the carbachol and electrical field induced spasms were in the range of 2.5 to 5 x 10(-4) g/ml.


Assuntos
Alcaloides de Berberina , Íleo/efeitos dos fármacos , Papaver/química , Parassimpatolíticos/farmacologia , Fenantridinas , Plantas Medicinais , Alcaloides/farmacologia , Animais , Benzofenantridinas , Berberina/análogos & derivados , Berberina/farmacologia , Carbacol/farmacologia , Estimulação Elétrica , Cobaias , Íleo/fisiologia , Técnicas In Vitro , Relaxamento Muscular/efeitos dos fármacos , Extratos Vegetais/farmacologia
4.
Planta Med ; 62(3): 227-31, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8693034

RESUMO

The influence of an ethanolic dry extract of Chelidonii herba on the GABAA receptor has been studied in vitro. In the presence of 90 micrograms/assay a positive cooperation was induced for [3H]muscimol accompanied by an increase of the specific binding (115%) while 160 micrograms/assay exerted a 50% inhibition of the specific binding of the radioligand [3H]muscimol. The quantitative determination of the Chelidonium alkaloids by HPLC together with the evaluation of the radioreceptor assays of the pure alkaloids revealed that the allosteric modulation of the GABAA receptor is mainly due to protopine. The small amounts of allocryptopine and stylopine assumingly support the action of protopine. Protopine, stylopine, and allocryptopine do not influence the specific binding of [3H]flunitrazepam. Thus, the positive cooperative modulation of the GABAA receptor is not based on an interaction of these alkaloids with the benzodiazepine receptor. The specific [3H]muscimol binding was inhibited only by chelerythrine and sanguinarine with IC50 values of 25 microM and 39 MicroM, respectively. The content of chelerythrine and sanguinarine in the ethanolic dry extract of Chelidonii herba is 500 or even 1000 times too low to account for the observed interference with GABAA receptor activity. Thus, the alkaloids are not responsible for the inhibitory action on the GABAA receptor at higher concentrations of the ethanolic dry extract.


Assuntos
Alcaloides/metabolismo , Alcaloides/farmacologia , Córtex Cerebral/metabolismo , Extratos Vegetais/farmacologia , Plantas Medicinais , Receptores de GABA-A/metabolismo , Alcaloides/isolamento & purificação , Animais , Membrana Celular/metabolismo , Masculino , Muscimol/metabolismo , Ensaio Radioligante , Ratos , Ratos Wistar , Trítio
5.
Chem Biol Interact ; 47(3): 293-305, 1983 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6317211

RESUMO

The effects of the hydroxyl free radical (OH), the superoxide free radical (O2-) and the trichloromethyl peroxy free radical (CC13O2) on the survival of bacteriophage T2 have been studied in the absence and presence of several non-steroidal anti-inflammatory drugs (NSAID). The trichloromethylperoxy radical derived from carbon tetrachloride is considerably more effective than the hydroxyl radical in inactivating the virus: the superoxide radical has only a minor inactivating effect. All the NSAID investigated (flurbiprofen, ibuprofen, sulindac, piroxicam, benoxaprofen, mefenamic acid, diflunisal, aspirin, D-penicillamine, indomethacin and metiazinic acid) inhibit inactivation by OH. This is in agreement with the high rate constants of reaction with this radical determined using the fast reaction technique of pulse radiolysis, i.e. (k greater than 10(9) M-1 S-1). The sulphur-containing drugs, metiazinic acid, piroxicam, penicillamine and sulindac as well as the indole derivative indomethacin, protect the virus from inactivation by the model peroxy radical CC13O2 (the dose modifying factor, DMF greater than 20). In contrast, acetylsalicylic acid related drugs, such as diflunisal, the anthranilic acid derivative, mefenamic acid, and some phenylpropionic acid derivatives, such as flurbiprofen, exhibit only a very small or no protective effect (DMF less than 2). As with OH, the ability of the drugs to protect the virus from inactivation by the peroxy radical is in agreement with their corresponding rate constants of reaction determined by pulse radiolysis.


Assuntos
Anti-Inflamatórios/farmacologia , Radicais Livres , Fagos T/efeitos dos fármacos , Hidróxidos/metabolismo , Hidróxidos/farmacologia , Radical Hidroxila , Cinética , Peróxidos/metabolismo , Peróxidos/farmacologia , Superóxidos/metabolismo , Superóxidos/farmacologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-6978295

RESUMO

The primary steps of the oxidation of methionine, Met, by X2.- (X = Cl; Br, I, SCN) have been investigated using pulse radiolysis techniques. In principle, the mechanism follows the same pattern which has been established for the OH radical induced oxidation. It is characterized by a primary attack at the sulphur atom and the formation of sulphur-centred radical cations S+. and S therefore (+) S as key intermediates. At pH greater than pKa of the carboxyl group these can then oxidize the amino function intramolecularly, which subsequently leads to irreversible decarboxylation. An additional important intermediate is a S therefore X radical with a three-electron bond between sulphur and halide. This radical is linked to the OH . radical induced mechanism through the equilibrium S therefore X + Met in equilibrium with S therefore (+) S + X-, and in addition exists in the equilibria X2.- + Met in equilibrium with S therefore X + X-, S therefore X in equilibrium with S+. + X- and S therefore X in equilibrium with Met + X.. The S therefore X- species absorb at 410, 400, and 390 nm for X = I, Br, and Cl, respectively. Absolute rate constants have been measured for the reactions S therefore (+) S + I- (k = 1.0 x 10(10) mol-1 ls-1, pH 1.4), Br2.- + Met (k = 2.5 x 10(9), 1.7 x 10(9), and 2.0 x 10(9) mol-1 ls-1 at pH 1, 5, and 11, respectively) and Cl2.- + Met (k = 3.9 x 10(9) mol-1 ls-1, pH 1). Methionine is also oxidized by (SCN)2.- whereas any significant oxidation by I2.- is not indicated. N-acetylmethionine, a model compound for a sulphur-containing peptide, and some other methionine derivatives are oxidized by X2.- in the same way, that is, through electrophilic addition at the sulphur function. The results require reinterpretation of some data published in the literature and are discussed in view of a 'selective free radical attack'.


Assuntos
Halogênios , Metionina , Radiólise de Impulso , Análise Espectral , Ânions , Radicais Livres , Cinética , Oxirredução
8.
Artigo em Inglês | MEDLINE | ID: mdl-6978296

RESUMO

Oxidation of methionine by Tl2+ and Ag2+ occurs with bimolecular rate constants of 2.5 x 10(9) and 3.3 x 10(8) mol-1 ls-1, respectively, and lead to sulphur-centred radical cations as primary intermediates. The overall mechanism is in principle the same as for OH. and X2.- (X = halide) induced oxidations with however one significant difference. Thus no oxidation of the amino group by S+. including subsequent decarboxylation is observed for methionine in its zwitterionic form while this readily occurs in the OH. and X2.- initiated mechanism. The reason is suggested to be complexing of the amino function by the metal ions which effectively lowers the reduction potential of the amino group. The sulphur-centred radical cation rather decays by a mostly first-order deprotonation process to yield CH2-S-CH2 approximately and CH3-S-CH approximately radicals of methionine. They absorb with lambda max = 290 mm and epsilon = 3000 +/- 600 mol-1 l cm-1, and exhibit reducing properties.


Assuntos
Metionina , Radiólise de Impulso , Prata , Análise Espectral , Tálio , Radicais Livres , Oxirredução
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