RESUMO
The 70% EtOH extract of Scoparia dulcis showed inhibitory activity against beta-glucuronidase from bovine liver. Bioassay-directed fractionation of the active extract led to the isolation of three labdane-type diterpene acids, scoparic acid A [1] [6-benzoyl-12-hydroxy-labda-8(17), 13-dien-18-oic acid], scoparic acid B [2] [6-benzoyl-14,15-dinor-13-oxo-8(17)-labden-18-oic acid], and scoparic acid C [3] [6-benzoyl-15-nor-14-oxo-8(17)-labden-18-oic acid], the structures of which were established by spectral means, including X-ray analysis. Scoparic acid A was found to be a potent beta-glucuronidase inhibitor.
Assuntos
Diterpenos/química , Glucuronidase/antagonistas & inibidores , Plantas Medicinais/química , Acetilação , Cristalização , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Espectroscopia de Ressonância Magnética , Metilação , Conformação Molecular , Paraguai , Difração de Raios XRESUMO
The structure of scopadulcic acid B (2, SDB), a major ingredient of the Paraguayan herb "Typychá kuratu" (Scoparia dulcis L.), was elucidated mainly by comparison of its spectral data with that of scopadulcic acid A (1). SDB inhibited both the K(+)-dependent adenosine triphosphatase (ATPase) activity of a hog gastric proton pump (H+, K(+)-ATPase) with a value of 20-30 microM for IC50 and proton transport into gastric vesicles. Pharmacokinetic studies of SDB in rats indicated that plasma SDB concentrations after i.v. injection of the sodium salt of SDB (SDB-Na) were described reasonably well by a two-compartment open model with Michaelis-Menten elimination kinetics. Plasma concentrations after oral administration of SDB-Na or SDB showed a much slower decline than what was expected following the i. v. study. It was suggested that the sustained plasma level of SDB after oral administration of SDB-Na or SDB was accounted for by relatively slow but efficient gastro-intestinal absorption in rats.
Assuntos
Adenosina Trifosfatases/antagonistas & inibidores , Antivirais/química , Diterpenos/química , Plantas Medicinais/análise , Animais , Antivirais/farmacocinética , Antivirais/farmacologia , Diterpenos/farmacocinética , Diterpenos/farmacologia , ATPase Trocadora de Hidrogênio-Potássio , Masculino , Paraguai , Ratos , Ratos Endogâmicos , Estômago/efeitos dos fármacos , Estômago/enzimologia , Suínos , Difração de Raios XRESUMO
For several years we have screened natural products having aldose reductase (AR) inhibitory activity. 3,3',4-Tri-O-methylellagic acid 4'-sulfate potassium salt (2) was isolated from a Mexican herb "Sinfito" (Potentilla candicans) as a potent AR inhibitory active constituent. 2 was more potent (IC50 = 8.0 x 10(-8)M) than ellagic acid, which is one of the natural inhibitors of AR. So we examined the synthesis of ellagic acid derivatives and found that the sulfate group is one of the important function.
Assuntos
Aldeído Redutase/antagonistas & inibidores , Plantas Medicinais/análise , Aldeído Redutase/metabolismo , Animais , Técnicas In Vitro , Cristalino/enzimologia , México , RatosRESUMO
The anti-inflammatory active fraction of the Paraguayan crude drug, "Alhucema," Lavandula latifolia Vill. afforded four compounds: coumarin (1), 7-methoxycoumarin (2), trans-phytol (3) and caryophyllene oxide (4). 1 showed a weakly inhibitory effect on carrageenin-induced paw edema in rats on topical application and 4 showed an inhibitory effect on histamine-induced contraction in guinea pig ileum.
Assuntos
Anti-Inflamatórios não Esteroides/análise , Cumarínicos/análise , Fitol/análise , Plantas Medicinais/análise , Sesquiterpenos/análise , Animais , Bioensaio , Cobaias , Técnicas In Vitro , Paraguai , Sesquiterpenos Policíclicos , RatosRESUMO
Aldose reductase (AR) inhibitory activity-directed fractionation of the 70% ethanolic extract of Para-parai mí, Phyllanthus niruri, has led to the isolation of three active components, ellagic acid (1), brevifolin carboxylic acid (4) and ethyl brevifolin carboxylate (5). Among them, 1 showed the highest inhibitory activity, being about 6 times more potent than quercitrin, which is a known natural inhibitor of AR.
Assuntos
Aldeído Redutase/antagonistas & inibidores , Plantas Medicinais/análise , Desidrogenase do Álcool de Açúcar/antagonistas & inibidores , Animais , Técnicas In Vitro , Paraguai , RatosRESUMO
Rats bearing lesions in the septal area (SA), or in the subfornical organ (SFO) or simultaneously in both regions were submitted to various thirst-eliciting procedures. The rats with hyperdipsia induced by lesion of the SA drank more water than either normal rats or SFO-lesioned animals under the same thirst-eliciting or angiotensin-liberating stimuli (polyethyleneglycol, isoproterenol, water deprivation and ligation of the inferior vena cava). The overdrinking elicited by SA lesions was blocked after SFO lesions. Neither hypovolemia, nor hypotension or water deprivation could elicit increased water intake in SFO-lesioned animals even after destruction of the SA. Animals with SFO lesions did not show increase of the water intake after cellular dehydration. The results obtained suggest that the SFO acts as the main structure in the regulation of water intake elicited by angiotensin with two opposite effects: one direct, facilitating water intake and the other indirect inhibiting the SA. The SA has an inhibitory effect on the SFO and on water intake.
Assuntos
Ingestão de Líquidos , Sistemas Neurossecretores/fisiologia , Núcleos Septais/fisiologia , Órgão Subfornical/fisiologia , Animais , Desidratação/induzido quimicamente , Ingestão de Líquidos/efeitos dos fármacos , Isoproterenol/farmacologia , Masculino , Polietilenoglicóis/farmacologia , Cloreto de Sódio/farmacologia , Sede/efeitos dos fármacos , Veia Cava Inferior/fisiologia , Privação de ÁguaRESUMO
Rats bearing lesions in the septal area (SA), or in the subfornical organ (SFO) or simultaneously in both regions were submitted to various thirst-eliciting procedures. The rats with hyperdipsia induced by lesion of the SA drank more water than either normal rats or SFO-lesioned animals under the same thirst-eliciting or angiotensin-liberating stimuli (polyethyleneglycol, isoproterenol, water deprivation and ligation of the inferior vena cava). The overdrinking elicited by SA lesions was blocked after SFO lesions. Neither hypovolemia, nor hypotension or water deprivation could elicit increased water intake in SFO-lesioned animals even after destruction of the SA. Animals with SFO lesions did not show increase of the water intake after cellular dehydration. The results obtained suggest that the SFO acts as the main structure in the regulation of water intake elicited by angiotensin with two opposite effects: one direct, facilitating water intake and the other indirect inhibiting the SA. The SA has an inhibitory effect on the SFO and on water intake.
RESUMO
Rats bearing lesions in the septal area (SA), or in the subfornical organ (SFO) or simultaneously in both regions were submitted to various thirst-eliciting procedures. The rats with hyperdipsia induced by lesion of the SA drank more water than either normal rats or SFO-lesioned animals under the same thirst-eliciting or angiotensin-liberating stimuli (polyethyleneglycol, isoproterenol, water deprivation and ligation of the inferior vena cava). The overdrinking elicited by SA lesions was blocked after SFO lesions. Neither hypovolemia, nor hypotension or water deprivation could elicit increased water intake in SFO-lesioned animals even after destruction of the SA. Animals with SFO lesions did not show increase of the water intake after cellular dehydration. The results obtained suggest that the SFO acts as the main structure in the regulation of water intake elicited by angiotensin with two opposite effects: one direct, facilitating water intake and the other indirect inhibiting the SA. The SA has an inhibitory effect on the SFO and on water intake.