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1.
Maturitas ; 58(1): 59-69, 2007 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-17658706

RESUMEN

OBJECTIVE: Increasing research suggested that Cimicifugae rhizoma might be protective against osteoporosis. In this study, we investigated the effects of three cycloartane-type triterpenoids isolated from Cimicifugae rhizoma, cimicidol-3-O-beta-D-xyloside (1), cimicidanol-3-O-beta-D-xyloside (2) and acetylacteol-3-O-beta-d-xyloside (3) on bone resorption in vitro and bone loss in ovariectomized (OVX) mice. METHODS: The activities of the tested compounds on bone resorption were evaluated using three assays, neonatal mouse parietal bone organ culture, osteoclast-like cells (OCLs) formation and pit formation. The effects on bone mineral density (BMD) and uterine weight were examined using OVX mice. Using LC-MS/MS method, the serum concentrations of the triterpenoids were measured in mice serum collected at 0.5, 1, 3, 6 and 12h following its oral administration. RESULTS: All of the tested compounds exerted the inhibitory effects on bone resorption in bone organ culture, suppressed both of the formation and the resorbing activity of OCLs. Furthermore, a synergistic effect was observed among those compounds. In vivo studies revealed that compounds 1-3 and the mixture of compounds 1-3 prevented the bone loss in OVX mice without affecting uterine weight, and each compound was detected in the mice serum after single oral administration. CONCLUSIONS: The triterpenoids exerted the inhibitory effects on osteoclastic bone resorption through the suppression of both OCLs formation and the resorbing activity of OCLs, and also showed a significant protective effect on BMD in OVX mice. The present results might provide a new pharmacological potential for the treatment of osteoporosis.


Asunto(s)
Resorción Ósea/tratamiento farmacológico , Cimicifuga/química , Medicamentos Herbarios Chinos/farmacología , Osteoclastos/efectos de los fármacos , Osteoporosis/tratamiento farmacológico , Ovariectomía/efectos adversos , Fitoterapia , Animales , Índice de Masa Corporal , Resorción Ósea/etiología , Cimicifuga/clasificación , Medicamentos Herbarios Chinos/química , Femenino , Ratones , Osteoporosis/etiología , Osteoporosis/prevención & control , Fitoterapia/métodos , Relación Estructura-Actividad , Resultado del Tratamiento , Triterpenos/química , Triterpenos/aislamiento & purificación
2.
Int J Radiat Oncol Biol Phys ; 49(5): 1369-79, 2001 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-11286845

RESUMEN

PURPOSE: The relationship between apoptosis induced by 42 degrees C and 44 degrees C hyperthermia alone or in combination with verapamil and changes in intracellular Ca(2+) concentration ([Ca(2+)]i) was investigated in U937 cells. METHODS: Apoptosis induced by hyperthermia was assessed according to DNA fragmentation, nuclear morphologic changes, and expression of phosphatidylserine on the outside plasma cell membrane. These changes were measured by flow cytometry. The [Ca(2+)]i of individual cells after hyperthermia was monitored by a digital image-analyzing technique using Fura-2. RESULTS: Hyperthermia-induced apoptosis reached a plateau after 6 h and was found to be both time and temperature-dependent. DNA fragmentation was maximum at 44 degrees C after 30 min. Verapamil enhanced the apoptosis induced by 42 degrees C and 44 degrees C hyperthermia in normal cells and by 44 degrees C hyperthermia in thermotolerant cells. The number of cells containing higher [Ca(2+)]i (more than 200 nM) was significantly increased by hyperthermia and further elevated by the addition of verapamil in both normal and thermotolerant cells. Apoptosis induced by hyperthermia was markedly decreased by an intracellular Ca(2+) chelator, BAPTA-AM, in a dose-dependent manner. CONCLUSION: These results indicate that [Ca(2+)]i increase plays a crucial role in apoptosis induced by hyperthermia and the combined treatment with verapamil in normal and thermotolerant U937 cells. Furthermore, hyperthermia-combined drug therapy has potential significance in cancer therapy.


Asunto(s)
Apoptosis/fisiología , Bloqueadores de los Canales de Calcio/farmacología , Calcio/metabolismo , Hipertermia Inducida , Verapamilo/farmacología , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Membrana Celular/efectos de la radiación , Quelantes/farmacología , Fragmentación del ADN , Relación Dosis-Respuesta a Droga , Ácido Egtácico/análogos & derivados , Ácido Egtácico/farmacología , Humanos , Fosfatidilserinas/metabolismo , Radiobiología , Temperatura , Factores de Tiempo , Células U937/efectos de los fármacos , Células U937/fisiología , Células U937/efectos de la radiación
3.
J Antibiot (Tokyo) ; 53(8): 788-92, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11079800

RESUMEN

A new metabolite, diheteropeptin, was found in the culture broth of Diheterospora chlamydosporia Q58044 by screening for TGF-beta-like active substances. Diheteropeptin was extracted from the culture supernatant and purified by a series of chromatographies such as silica gel, gel filtration and HPLC. Diheteropeptin exhibited cytostatic activity in Mv1Lu cells with an IC50 value of 20.3 microM and inhibited histone deacetylase.


Asunto(s)
Ácidos Decanoicos/aislamiento & purificación , Ácidos Decanoicos/farmacología , Hypocreales/metabolismo , Péptidos , Antibacterianos/farmacología , División Celular/efectos de los fármacos , Células Cultivadas , Ácidos Decanoicos/metabolismo , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos/métodos , Inhibidores Enzimáticos/farmacología , Fermentación , Inhibidores de Histona Desacetilasas , Humanos , Concentración 50 Inhibidora , Factor de Crecimiento Transformador beta/farmacología
4.
Phytochemistry ; 54(1): 13-7, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10846740

RESUMEN

All stereoisomers of methyl jasmonate (MJA) were prepared, and their effects on cell yield and promotion of paclitaxel (Taxol) and baccatin III production investigated in cell suspension cultures of Taxus media. (3R,7S)-MJA showed the strongest cell growth inhibition, followed by (3R,7R)-MJA. In contrast, (3S,7R)- and (3S,7S)-MJA had very low inhibitory effects, indicating that this inhibition depends largely on the (3R)-configuration. In terms of the promotion of paclitaxel and baccatin III production, (3R,7R)-MJA had the highest activity. Although it showed considerable activity at low concentration, at higher concentrations the activity was decreased due to strong inhibition of cell growth. Interestingly, paclitaxel and baccatin III contents increased even at a high (3S,7R)-MJA concentration, whereas the other isomers had the opposite effects. These findings are interpreted to suggest that the optimum configuration is (3R,7R), the (3R)-configuration not being indispensable, and that the (7R)-configuration is suitable for the promotion of paclitaxel and baccatin III production.


Asunto(s)
Acetatos/metabolismo , Alcaloides/biosíntesis , Antineoplásicos Fitogénicos/biosíntesis , Ciclopentanos/metabolismo , Paclitaxel/biosíntesis , Plantas Medicinales , Taxoides , Taxus/metabolismo , Acetatos/química , División Celular , Células Cultivadas , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Ciclopentanos/química , Oxilipinas , Estereoisomerismo , Taxus/química , Taxus/citología
5.
Schizophr Res ; 42(3): 209-22, 2000 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-10785579

RESUMEN

Regional cerebral blood flow (rCBF) during a verbal learning task was measured using 99mTc-ethyl-cysteinate dimer and single photon emission computed tomography in 10 patients with schizophrenia and nine normal controls. Verbal repetition was used as a control task. The schizophrenic patients showed failure to spontaneously utilize implicit category information to learn the word lists. In the normal controls, rCBF in the left inferior frontal and left anterior cingulate regions was significantly increased during the verbal learning task, compared with the verbal repetition task. In contrast, there was no significant frontal lobe activation by the verbal learning in the schizophrenic patients. The patients had lower rCBF during the verbal learning task than the controls in the bilateral inferior frontal, left anterior cingulate, right superior frontal, and bilateral middle frontal regions. Activation in the left inferior frontal region was significantly positively correlated with categorical clustering in the task in the controls, but no such correlation was found in the patients. These results indicate that memory organization deficits in schizophrenia may be related to dysfunction in the prefrontal areas, especially in the left inferior frontal region.


Asunto(s)
Lóbulo Frontal/irrigación sanguínea , Lóbulo Frontal/diagnóstico por imagen , Trastornos de la Memoria/complicaciones , Esquizofrenia/complicaciones , Tomografía Computarizada de Emisión de Fotón Único , Aprendizaje Verbal/fisiología , Adulto , Cisteína/análogos & derivados , Lóbulo Frontal/anatomía & histología , Lateralidad Funcional/fisiología , Humanos , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Masculino , Trastornos de la Memoria/diagnóstico , Compuestos de Organotecnecio , Radiofármacos , Reproducibilidad de los Resultados , Esquizofrenia/diagnóstico , Índice de Severidad de la Enfermedad
8.
Biol Pharm Bull ; 22(4): 391-6, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10328560

RESUMEN

We previously isolated berberine from aqueous extracts of tsu-kan-gan, a Kampo formula used for the treatment of osteoporosis. Berberine caused an inhibitory effect on parathyroid hormone (PTH)-stimulated bone resorption in neonatal mouse bone. In this report we describe the inhibitory effect of berberine on the formation of osteoclast-like multinucleated cells (OCLs) in the co-culture of mouse osteoblastic cells and bone marrow cells in the presence of 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3], PTH and interleukin-1alpha (IL-1alpha). Berberine dose-dependently inhibited the formation of tartrate-resistant acid phosphatase (TRAP)-positive OCLs induced by 1alpha25(OH)2D3, PTH and IL-1alpha. We prepared OCLs in the co-culture of osteoblastic cells and bone marrow cells. The effect of berberine on pit formation by OCLs was examined using dentin slices. As OCLs are terminally differentiated multinucleated cells, the survival of OCLs affects the bone-resorbing activity of OCLs. This prompted us to count the number of TRAP-positive OCLs on the slices. Berberine dose-dependently inhibited pit formation and caused a decrease in the number of TRAP-positive OCLs. Calcitonin (CT) inhibited pit formation without affecting the number of OCLs. Berberine accelerated the cell death in OCLs cultivated on a culture plate, but CT did not affect the cell death of OCLs. This suggests that the decrease in the number of OCLs on dentin slices may be due to apoptotic cell death in OCLs. In fact, Hoechst 33258 staining revealed that the treatment of OCLs with berberine resulted in condensed nuclei and a decrease in cell size. Oral administration of the berberine (30 and 50 mg/kg/d) to ovariectomized rats prevented a decrease in bone mineral density (BMD) of the lumbar vertebra without affecting the weight of the uterus and plasma concentration of estradiol. These results suggested that berberine prevented a decrease in BMD in vivo by inhibiting osteoclastic bone resorption.


Asunto(s)
Berberina/farmacología , Resorción Ósea , Medicamentos Herbarios Chinos/farmacología , Macrólidos , Animales , Antibacterianos/farmacología , Apoptosis/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Densidad Ósea/efectos de los fármacos , Calcitonina/farmacología , Calcitriol/farmacología , Femenino , Interleucina-1/farmacología , Masculino , Ratones , Tamaño de los Órganos/efectos de los fármacos , Osteoclastos/citología , Osteoclastos/efectos de los fármacos , Ovariectomía , Hormona Paratiroidea/farmacología , Ratas , Ratas Wistar , Útero/efectos de los fármacos
9.
Phytomedicine ; 6(5): 305-10, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11962535

RESUMEN

We studied the effect of low molecular weight chitosan (LMWC) on the formation of osteoclast-like multinucleated cells (OCLs) in the co-culture of mouse osteoblastic cells and bone marrow cells in the presence of 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3]. LMWC at 440 microg/ml inhibited the formation of tartrate-resistant acid phosphatase (TRAP)-positive OCLs induced by 1alpha,25(OH)2D3. We prepared OCLs in the co-culture of osteoblastic cells and bone marrow cells. The effect of LMWC on pit formation by OCLs was examined using dentin slices, and LMWC inhibited pit formation at 440 microg/ml. Oral administration of the LMWC to ovariectomized rats prevented a decrease in bone mineral density (BMD) of the lumbar vertebra without affecting the body and uterus weights. These results suggested that LMWC prevented a decrease in BMD in vivo by inhibiting osteoclastic bone resorption.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Células de la Médula Ósea/efectos de los fármacos , Resorción Ósea/tratamiento farmacológico , Quitina/química , Quitina/farmacología , Osteoblastos/efectos de los fármacos , Osteoclastos/efectos de los fármacos , Animales , Animales Recién Nacidos , Peso Corporal/efectos de los fármacos , Calcitriol/farmacología , Diferenciación Celular/efectos de los fármacos , Línea Celular , Quitina/análogos & derivados , Técnicas de Cocultivo , Dentina/efectos de los fármacos , Dentina/fisiología , Femenino , Vértebras Lumbares/efectos de los fármacos , Vértebras Lumbares/fisiología , Masculino , Ratones , Peso Molecular , Tamaño de los Órganos/efectos de los fármacos , Osteoblastos/citología , Osteoclastos/citología , Ovariectomía , Ratas , Ratas Wistar , Útero/efectos de los fármacos
10.
Biol Pharm Bull ; 21(6): 594-8, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9657044

RESUMEN

We previously found that a methanolic extract of the stems of Sambucus sieboldiana inhibited bone resorption in organ culture. In this study, we further fractionated the methanol extract guided by the activity towards bone resorption stimulated by parathyroid hormone (PTH) in vitro. The ethyl acetate fraction (EtOAc Fr.) of the methanolic extract inhibited PTH-stimulated bone resorption of neonatal mouse bones, and the inhibitory activity was more potent than those of other fractions. Oral administration of the EtOAc Fr. (50 and 100 mg/kg/d) to ovariectomized (OVX) rat prevented the decrease in bone mineral density (BMD) of the lumbar (L2-4) vertebra, indicating that the EtOAc Fr. is effective in vivo. Furthermore, the EtOAc Fr. (50, 100 and 150 mg/kg/d) decreased the serum calcium level elevated in low calcium dietary rats. The phenolic constituents of the EtOAc fraction were examined for their inhibitory effect on bone resorption stimulated by PTH in neonatal mouse bone. Among them, vanillic acid, vanillin and coniferyl alcohol showed significant inhibitory effects on bone resorption. Of the compounds examined, vanillic acid was found to have a significant inhibitory effect on the decrease of BMD in OVX mice. Therefore, the EtOAc Fr. of S. sieboldiana showed a suppressive effect on bone resorption in vitro and in vivo. In addition, the inhibitory effects of the EtOAc Fr. on bone resorption may be at least partly due to the inhibitory action of vanillic acid.


Asunto(s)
Resorción Ósea/tratamiento farmacológico , Plantas Medicinales/química , Acetatos , Animales , Benzaldehídos/farmacología , Densidad Ósea/efectos de los fármacos , Resorción Ósea/inducido químicamente , Calcio/sangre , Calcio/deficiencia , Calcio de la Dieta/administración & dosificación , Ratones , Ovariectomía , Hormona Paratiroidea/toxicidad , Fenoles/farmacología , Extractos Vegetales/farmacología , Ratas , Ratas Wistar , Solventes , Factores de Tiempo , Ácido Vanílico/farmacología
11.
Biol Pharm Bull ; 21(12): 1322-6, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9881647

RESUMEN

Four water extracts of Kampo formulae (Yi-kkan-sen, Dai-ho-in-gan, Ni-chi-gan, Tsu-kan-gan) were screened for their inhibitory activities on bone resorption induced by parathyroid hormone (PTH) in organ culture using neonatal mouse parietal bones. Among the Kampo formulae, Tsu-kan-gan (TKG) showed the most potent inhibitory activity. We further fractionated the TKG water extract by monitoring the inhibitory activity on bone resorption stimulated by PTH in vitro. The MeOH fraction of the water extract inhibited PTH-stimulated bone resorption, and its inhibitory activity was more potent than those of other fractions. The MeOH fraction was then subjected to Sephadex LH-20 column chromatography to give fractions I, II and III, which were examined for bone resorption activity. Fraction I inhibited PTH-stimulated bone resorption, and its inhibitory activity was more potent than those of the other fractions. Upon oral administration of the three fractions (100 mg/kg/d) to ovariectomized (OVX) mice, fractions I and III prevented the decrease of bone mineral density (BMD) of the lumbar vertebra. Eleven compounds isolated from the MeOH fraction were examined for their inhibitory effect on PTH-stimulated bone resorption. Among them, berberine (1), syringin (3), limonin (4) and mangiferin (10) showed a significant inhibitory effect on bone resorption. In the formation assay of osteoclast-like cells, these compounds decreased the number of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells (MNCs). The inhibitory effect of TKG on bone resorption may be at least partly due to the inhibitory action of these compounds.


Asunto(s)
Resorción Ósea/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Animales , Densidad Ósea/efectos de los fármacos , Resorción Ósea/inducido químicamente , Química Farmacéutica , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Femenino , Medicina Tradicional China , Metanol/química , Ratones , Osteoclastos/efectos de los fármacos , Osteoporosis/tratamiento farmacológico , Ovariectomía , Hormona Paratiroidea
12.
Phytomedicine ; 3(4): 379-85, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23195197

RESUMEN

We studied the effects of ethyl acetate-(EtOAc) soluble fractions from methanol (MeOH) extracts of Cimicifugae rhizoma derived from two species - Cimicifuga heracleifolia Komarov and C. foetida L. - and four triterpenoids (1-4) isolated from them on the serum calcium (Ca) and phosphate (P) levels in low - Ca dietary rats. The EtOAc-soluble fraction from C. heracleifolia Komarov (HE) significantly drecreased Ca levels when administered. Similarly, the EtOAc-soluble fraction from C. foetida L. (FE) significantly lowered serum Ca levels at doses of 100 and 200 mg/kg/day, while the four triterpenoids (1-4) did the same at a dose of 25mg/kg/day. Interestingly only 7,8-didehydro-24-0-acetylhydroshengmanol-3-0-ß-xyloside (4) showed a significant influence on serum P levels. The effects of HE and FE on the bone mineral density (BMD) of the lumbar spine (L 2-4) in ovariectomized rats were measured by dual energy X-ray absorptiometry (DXA). Rats treated with HE and FE showed a significant increase in BMD compared to untreated ovariectomized rats. BMD was lower in the latter than in sham-operated rats.

13.
Radiat Med ; 14(3): 159-61, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8827812

RESUMEN

A 32-year-old pregnant woman at 29 gestational weeks suffered from the acute onset of severe headache. Brain CT, MRI, and MR angiography (MRA) showed intraventricular and thalamic hemorrhage, ruptured from a thalamic AVM. Based on these findings, conservative treatment was continued until delivery. After cesarean delivery at 34 gestational weeks, conventional cerebral angiography was performed, followed later by gamma-knife therapy. In pregnant patients with suspected cerebrovascular disorders, MRI and MRA should be the first of choice method to evaluate information on the diseased vessels and associated lesions since there is no radiation risk or side effects of contrast medium.


Asunto(s)
Malformaciones Arteriovenosas Intracraneales/diagnóstico , Angiografía por Resonancia Magnética/métodos , Complicaciones Cardiovasculares del Embarazo/diagnóstico , Tálamo/irrigación sanguínea , Adulto , Femenino , Humanos , Embarazo , Rotura Espontánea , Tomografía Computarizada por Rayos X
14.
Science ; 270(5244): 1988-92, 1995 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-8533090

RESUMEN

A complementary DNA encoding a mitogen-activated protein (MAP) kinase homolog has been isolated from tobacco plants. Transcripts of the corresponding gene were not observed in healthy tobacco leaves but began to accumulate 1 minute after mechanical wounding. In tobacco plants transformed with the cloned complementary DNA, trans inactivation of the endogenous homologous gene occurred, and both production of wound-induced jasmonic acid and accumulation of wound-inducible gene transcripts were inhibited. In contrast, the levels of salicylic acid and transcripts for pathogen-inducible, acidic pathogenesis-related proteins were increased upon wounding. These results indicate that this MAP kinase is part of the initial response of higher plants to mechanical wounding.


Asunto(s)
Proteínas Quinasas Dependientes de Calcio-Calmodulina/genética , Genes de Plantas , Nicotiana/enzimología , Plantas Tóxicas , Transducción de Señal , Secuencia de Aminoácidos , Proteínas Quinasas Dependientes de Calcio-Calmodulina/química , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Ciclopentanos/metabolismo , ADN Complementario/genética , Datos de Secuencia Molecular , Oxilipinas , Fosfolipasas A/metabolismo , Fosforilación , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Salicilatos/metabolismo , Ácido Salicílico , Nicotiana/genética
15.
J Antibiot (Tokyo) ; 46(8): 1232-8, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8407585

RESUMEN

Exfoliazone and lavanducyanin isolated from Streptomyces exfoliatus BT-38 and Streptomyces aeriouvifer CL-190, respectively, showed strong growth promoting activities to liver cell RLN-8 established from normal Donryu rat. When RLN-8 cells were cultured in Eagle's minimal essential medium containing 1% fetal bovine serum, exfoliazone significantly stimulated the growth of RLN-8 cells. However, no effect was observed under serum-free conditions. Effective dose of exfoliazone was at the range of 0.004-0.1 microgram/ml. Cell proliferation was confirmed by MTT assay and by the increases of cell number and DNA synthesis. Lavanducyanin also stimulated the growth of RLN-8 cells in the same medium. It showed growth promoting activity at lower concentrations than exfoliazone and the effective dose was at the range of 0.0001-0.06 microgram/ml. Analogous compounds of exfoliazone and lavanducyanin also promoted the growth of RLN-8 cells. In addition, exfoliazone and lavanducyanin enhanced the growth of NIH 3T3 and T601 cells. These results indicate that exfoliazone, lavanducyanin and their related compounds seem to be a new type of growth promoting substances with low molecular weight produced by microorganisms, and that they can partially substitute for functions of serum. Since 12-O-tetradecanoylphorbol-13-acetate (TPA) did not show the growth promoting activities under the same conditions, the action mechanism(s) of exfoliazone and lavanducyanin are different from that of TPA.


Asunto(s)
División Celular/efectos de los fármacos , Sustancias de Crecimiento/farmacología , Fenazinas/farmacología , Streptomyces/metabolismo , Animales , Línea Celular , Evaluación Preclínica de Medicamentos , Hígado/citología , Hígado/efectos de los fármacos , Oxazinas/farmacología , Ratas
16.
J Bacteriol ; 174(21): 6857-61, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1400236

RESUMEN

Phosphoenolpyruvate phosphomutase (PEPPM) catalyzes C-P bond formation by intramolecular rearrangement of phosphoenolpyruvate to phosphonopyruvate (PnPy). We purified PEPPM from a gram-negative bacterium, Pseudomonas gladioli B-1 isolated as a C-P compound producer. The equilibrium of this reaction favors the formation of the phosphate ester by cleaving the C-P bond of PnPy, but the C-P bond-forming reaction is physiologically significant. The C-P bond-forming activity of PEPPM was confirmed with a purified protein. The molecular mass of the native enzyme was estimated to be 263 and 220 kDa by gel filtration and polyacrylamide gel electrophoresis, respectively. A subunit molecular mass of 61 kDa was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, indicating that the native protein was a tetramer. The optimum pH and temperature were 7.5 to 8.0 and 40 degrees C, respectively. The Km value for PnPy was 19 +/- 3.5 microM, and the maximum initial velocity of the conversion of PnPy to phosphoenolpyruvate was 200 microM/s/mg. PEPPM was activated by the presence of the divalent metal ion, and the Km values were 3.5 +/- 1.4 microM for Mg2+, 16 +/- 5 nM for Mn2+, 3.0 +/- 1.5 microM for Zn2+, and 1.2 +/- 0.2 microM for Co2+.


Asunto(s)
Isomerasas/aislamiento & purificación , Fosfotransferasas (Fosfomutasas) , Pseudomonas/enzimología , Carbono/química , Concentración de Iones de Hidrógeno , Isomerasas/efectos de los fármacos , Cinética , Magnesio/farmacología , Peso Molecular , Fósforo/química
17.
Radiat Med ; 10(5): 196-8, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1332132

RESUMEN

Tissue distribution studies of intravenously injected [131I]Lipiodol in rats were performed, and serial whole-body autoradiograms were obtained simultaneously for seven days. Most of the radiotracer was retained in the lungs. Lung uptake reached a maximum (42.44% ID/g) at 1 day, with an effective half-life of 3.0 days. The other organs showed markedly lower uptakes (less than 0.56% ID/g). The ratio between liver and lung reached a maximum (0.01) at 3 hr and then decreased with time, precluding adequate external imaging of the liver as compared with the lung.


Asunto(s)
Aceite Yodado/farmacocinética , Animales , Autorradiografía , Semivida , Inyecciones Intravenosas , Mucosa Intestinal/metabolismo , Radioisótopos de Yodo , Aceite Yodado/administración & dosificación , Riñón/metabolismo , Hígado/metabolismo , Pulmón/metabolismo , Masculino , Músculos/metabolismo , Miocardio/metabolismo , Ratas , Ratas Wistar , Bazo/metabolismo , Testículo/metabolismo , Factores de Tiempo , Distribución Tisular
18.
Chem Pharm Bull (Tokyo) ; 39(11): 2956-61, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1799941

RESUMEN

Three phenolic compounds were isolated from the roots of Arnebia euchroma as inhibitors of in vitro prostaglandin biosynthesis. Two known compounds were identified as shikonofurans and des-O-methyllasiodiplodin. The other new compound was named arnebinol and its structure was elucidated as a novel ansa-type monoterpenylbenzenoid derivative.


Asunto(s)
Plantas Medicinales/química , Prostaglandinas/biosíntesis , Terpenos/análisis , Animales , Depresión Química , Técnicas In Vitro , Médula Renal/efectos de los fármacos , Médula Renal/metabolismo , Extractos Vegetales/análisis , Extractos Vegetales/farmacología , Conejos , Terpenos/farmacología
19.
Chem Pharm Bull (Tokyo) ; 39(11): 2962-4, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1799942

RESUMEN

Two quinonic compounds, arnebinone and arnebifuranone, were isolated from the roots of Arnebia euchroma and their structures were elucidated on the basis of spectral evidence. Arnebionone is a monoterpenyl-benzoquinone in which the monoterpene moiety forms a fused ring to the benzoquinone. Arnebifuranone is another monoterpenylbenzoquinone with a furan ring containing side chain which is bonded to the benzoquinone at the head carbon of C10 moiety originating from the geranyl moiety of geranylhydroquinone.


Asunto(s)
Benzoquinonas/análisis , Furanos/análisis , Naftoquinonas/análisis , Plantas Medicinales/química , Prostaglandinas/biosíntesis , Animales , Benzoquinonas/farmacología , Depresión Química , Furanos/farmacología , Técnicas In Vitro , Médula Renal/efectos de los fármacos , Médula Renal/metabolismo , Naftoquinonas/farmacología , Extractos Vegetales/análisis , Conejos
20.
Nature ; 335(6189): 457-8, 1988 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-3138545

RESUMEN

The first isolation of a naturally occurring phosphonate in 1959 led rapidly to the discovery of a variety of metabolites containing a phosphorus-carbon bond. Phosphonates have been found in bacteria, fungi, and higher organisms such as the snail schistosome vector Biomphalaria. The biosynthetic path to the P-C bond has, however, remained undefined. Thus although it was shown twenty years ago that the isotope label from [14C]glucose or from [32P]phosphoenolpyruvate is incorporated into 2-aminoethylphosphonate by the protozoan Tetrahymena pyriformis, the presumed stoichiometric transformation of phosphoenolpyruvate to phosphonopyruvate has never been demonstrated. Low conversions of phosphoenolpyruvate into 2-aminoethylphosphonate and the trapping of phosphonopyruvate from phosphoenolpyruvate have been reported, but these reactions have not proved reproducible, and the existence of the critical enzyme, phosphoenolpyruvate phosphonomutase, has remained notional. We now report experiments that resolve this enigma, and describe the isolation and characterization of the pure mutase from T. pyriformis.


Asunto(s)
Isomerasas/aislamiento & purificación , Fosfoenolpiruvato/metabolismo , Fosfotransferasas (Fosfomutasas) , Piruvatos/biosíntesis , Secuencia de Aminoácidos , Animales , Biomphalaria/enzimología , Carbono/metabolismo , Isomerasas/metabolismo , Datos de Secuencia Molecular , Fósforo/metabolismo , Tetrahymena pyriformis/enzimología
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