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1.
J Food Sci ; 72(1): S049-54, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17995897

RESUMO

We formulated a filling for sandwich cookies containing 400 mg of eicosapentaenoic acid, 20:5, n-3 (EPA) + docosahexaenoic acid, 22:6, n-3 (DHA) encapsulated in a matrix of starch and gelatin. Cookies were stored at 2 different temperatures (18 degrees C and 35 degrees C) and under 2 different packaging conditions (atmospheric and vacuum packed) for 28 d. At regular intervals, cookies were analyzed for moisture, water activity, and concentrations of EPA, DHA, and dienes. Results showed that there were no significant losses of EPA and DHA during storage under the conditions of study. A maximum loss of 5% was observed after 28 d of storage. The concentration of dienes obtained under different conditions were low (< 25 mmol/kg) as compared to a salmon oil sample with appreciable signs of oxidation (600 mmol/kg). Sensory evaluation of cookies by an untrained panel of healthy consumers and ulcerative colitis patients revealed no aftertaste and high acceptability of the cookies. Our results demonstrated that it is possible to make shelf-stable fortified foods with high levels of long-chain omega3FA.


Assuntos
Ácidos Graxos Ômega-3/análise , Embalagem de Alimentos/métodos , Alimentos Fortificados , Alimentos Orgânicos , Comportamento do Consumidor , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácidos Docosa-Hexaenoicos/análise , Ácidos Docosa-Hexaenoicos/química , Ácido Eicosapentaenoico/administração & dosagem , Ácido Eicosapentaenoico/análise , Ácido Eicosapentaenoico/química , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Ômega-3/química , Humanos , Oxirredução , Paladar , Temperatura , Fatores de Tempo , Água/metabolismo
2.
Compr Rev Food Sci Food Saf ; 3(4): 127-139, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33430565

RESUMO

Intense interest in nutraceuticals and their potential benefits has created the need to review the existing scientific information on their effect in preventing and managing inflammation that accompanies most chronic diseases. This article reviews the basic mechanisms of inflammation and the potential of 9 nutraceuticals to be effective as chronic disease preventive agents. Furthermore, the article emphasizes studies in which nutraceuticals are shown to be effective in preventing inflammation and mentions other molecular targets that can be of use in the future. The effects of the following nutraceuticals: α-tocopherol, ascorbic acid, curcumin, resveratrol, (-)-epigallocatechin gallate, theaflavin, genistein, omega-3 fatty acids, and lycopene on reactive oxygen species scavenging ability, as well as proinflammatory targets, such as tumor necrosis factor α interleukin-1, interleukin-1ß, nuclear factor kappa B, cellular and adhesion molecules, cyclooxygenase-2, inducible nitric oxide synthase, 5-lipoxygenase (5-LOX), phospholipase A2 , reactive oxygen species generating enzymes are discussed.

3.
J Agric Food Chem ; 49(9): 4478-81, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11559157

RESUMO

One new iridoid glycoside and five known flavonol glycosides have been isolated from the leaves of Morinda citrifolia. The new iridoid exists as an epimeric mixture in solution. Complete assignments of the proton and carbon chemical shifts for the individual epimers were accomplished on the basis of high-resolution 1D and 2D NMR data. Their antioxidative activities were measured. All of these compounds showed DPPH free radical scavenging activity at the concentration of 30 microM.


Assuntos
Glicosídeos/química , Folhas de Planta/química , Antioxidantes , Flavonoides , Flavonóis , Sequestradores de Radicais Livres , Glicosídeos/análise , Espectroscopia de Ressonância Magnética
4.
J Nat Prod ; 64(6): 799-800, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11421748

RESUMO

A new iridoid glucoside (1), named citrifolinoside A, was isolated from the leaves of Morinda citrifolia along with the known iridoids asperuloside and asperulosidic acid. The structure of 1 was established by interpretation and full assignments of NMR spectroscopic data.


Assuntos
Glucosídeos/química , Plantas Medicinais/química , Piranos/química , Glucosídeos/isolamento & purificação , Oceano Índico , Glucosídeos Iridoides , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Folhas de Planta/química , Piranos/isolamento & purificação , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
6.
Phytochemistry ; 56(7): 723-7, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11314959

RESUMO

Bioactivity-directed fractionation and purification afforded cytotoxic components of Commiphora wightii. The exudates of C. wightii were extracted with EtOAc and the extract was subjected to repeated column chromatography. A fraction showing cytotoxic activity was characterized as a mixture of two ferulates with an unusual skeleton by spectral and chemical methods, including by NMR, GC-MS and chemical derivatization. This fraction also showed moderate scavenging effect against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals.


Assuntos
Antineoplásicos Fitogênicos/química , Sobrevivência Celular/efeitos dos fármacos , Extratos Vegetais/química , Rosales/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/toxicidade , Neoplasias da Mama , Commiphora , Feminino , Sequestradores de Radicais Livres/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Masculino , Gomas Vegetais , Neoplasias da Próstata , Células Tumorais Cultivadas
7.
Carcinogenesis ; 22(2): 321-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11181455

RESUMO

Resveratrol, a trihydroxystilbene found in grapes and other plants, has been shown to be active in inhibiting multistage carcinogenesis. Using resveratrol as a prototype, we have synthesized a number of polyhydroxy- and polymethoxy-stilbenes and tested their anti-proliferative effect in normal and transformed human cells. Here we show that one of the resveratrol analogs, 3,4,5,4'-tetrahydroxystilbene (R-4), specifically inhibited the growth of SV40 virally transformed WI38 cells (WI38VA) at 10 microM, but had no effect on normal WI38 cells at even higher concentrations. R-4 also prominently induced apoptosis in WI38VA cells, but not in WI38 cells. RNase protection assay showed that R-4 significantly induced the expression of p53, GADD45 and Bax genes and concomitantly suppressed the expression of bcl-2 gene in WI38VA, but not in WI38 cells. A large increase in p53 DNA binding activity and the presence of p53 in the Bax promoter binding complex suggested that p53 was responsible for the Bax gene expression induced by R-4 in transformed cells. Within 4 h of treatment with R-4, the Bax to bcl-2 protein ratio in WI38 and WI38VA cells was, respectively, 0.1 and 105, a difference of three orders of magnitude. While R-4 prominently induced the p53/Bax pro-apoptotic genes, it also concomitantly suppressed the expression of Cox-2 in WI38VA cells. Taken together, our study suggests that the induction of p53 gene by R-4 in transformed cells may play a key role in the differential growth inhibition and apoptosis of transformed cells.


Assuntos
Apoptose/efeitos dos fármacos , Transformação Celular Viral/efeitos dos fármacos , Proteínas Proto-Oncogênicas/genética , Estilbenos/farmacologia , Proteína Supressora de Tumor p53/genética , Bacteriocinas/genética , Bacteriocinas/metabolismo , Western Blotting , Divisão Celular/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , Ciclo-Oxigenase 2 , Primers do DNA/química , Eletroforese em Gel de Ágar , Fibroblastos/efeitos dos fármacos , Expressão Gênica , Humanos , Marcação In Situ das Extremidades Cortadas , Peptídeos e Proteínas de Sinalização Intracelular , Isoenzimas/genética , Isoenzimas/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/fisiologia , Proteínas de Membrana , Prostaglandina-Endoperóxido Sintases/genética , Prostaglandina-Endoperóxido Sintases/metabolismo , Proteínas/genética , Proteínas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2 , Proteínas GADD45
8.
Cancer Res ; 60(22): 6465-71, 2000 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11103814

RESUMO

Theaflavin (TF-1), theaflavin-3-monogallate and theaflavin-3'-monogallate mixture (TF-2), and theaflavin-3,3'-digallate (TF-3) are the major black tea polyphenols. Here we compared the effects of these polyphenols on cell growth, apoptosis, and gene expression in normal and cancerous cells. We showed that TF-2 (10-50 microM) inhibited the growth of SV40 transformed WI38 human cells (WI38VA) and Caco-2 colon cancer cells but had little effect on the growth of their normal counterparts. The IC50s of TF-2 for the growth inhibition of WI38 and WI38VA cells were, respectively, 300 and 3 microM. The other two black tea polyphenols, TF-1 and TF-3, did not exhibit such differential growth-inhibitory effect. TF-2, but not TF-1 or TF-3, induced apoptosis in transformed WI38VA cells but not in normal WI38 cells, suggesting that apoptosis was responsible, at least in part, for the differential growth-inhibitory effect of TF-2. Cox-2 has been implicated in intestinal carcinogenesis. Among the tea polyphenols tested, TF-2 and, to a lesser degree, (-)-epigallocatechin gallate inhibited cyclooxygenase (Cox)-2 gene expression. TF-2 at 50 microM completely blocked the serum-induced Cox-2 gene expression at both mRNA and protein level. Other genes, including c-fos, c-myc, thymidine kinase, proliferating cell nuclear antigen, BRCA1, BRCA2, and Cox-1, were not significantly affected by TF-2. These findings suggest that TF-2 may be responsible, at least in part, for the chemopreventive activity in black tea extracts.


Assuntos
Antioxidantes/farmacologia , Biflavonoides , Células CACO-2/efeitos dos fármacos , Colo/efeitos dos fármacos , Ácido Gálico/análogos & derivados , Ácido Gálico/farmacologia , Isoenzimas/genética , Prostaglandina-Endoperóxido Sintases/genética , Apoptose/efeitos dos fármacos , Células CACO-2/citologia , Células CACO-2/enzimologia , Catequina , Divisão Celular/efeitos dos fármacos , Divisão Celular/genética , Linhagem Celular Transformada , Colo/citologia , Colo/enzimologia , Técnicas de Cultura , Ciclo-Oxigenase 2 , Expressão Gênica/efeitos dos fármacos , Inibidores do Crescimento/farmacologia , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/biossíntese , Proteínas de Membrana , Prostaglandina-Endoperóxido Sintases/biossíntese , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/genética , Chá
9.
J Nat Prod ; 63(8): 1182-3, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10978225

RESUMO

Three new glycosides were isolated from the fruits of noni (Morinda citrifolia). Their structures were determined to be 6-O-(beta-D-glucopyranosyl)-1-O-octanoyl-beta-D-glucopyranose (1), 6-O-(beta-D-glucopyranosyl)-1-O-hexanoyl-beta-D-glucopyranose (2), and 3-methylbut-3-enyl 6-O-beta-D-glucopyranosyl-beta-D-glucopyranoside (3) using MS and NMR methods.


Assuntos
Frutas/química , Glicosídeos/isolamento & purificação , Plantas Medicinais/química , Rubiaceae/química , Cromatografia em Gel , Cromatografia em Camada Fina , Cromatografia Gasosa-Espectrometria de Massas , Glucosídeos/química , Glucosídeos/isolamento & purificação , Glicosídeos/química , Havaí , Espectroscopia de Ressonância Magnética , Rotação Ocular , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria Infravermelho
10.
Anticancer Res ; 20(4): 2653-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10953339

RESUMO

Herbal therapies are commonly used by patients with cancer, despite little understanding about their clinical and biological activity. We recently demonstrated that the herbal combination PC-SPES, which contains licorice root, had potent estrogenic activity in vitro, in animals, and in patients with prostate cancer. Licochalcone-A (LA) is one flavonoid extracted from licorice root with antiparasitic and anti-tumor activity, but the effect on the human estrogen receptor and mechanism of anti-tumor activity is unknown. Recent studies demonstrated that the mechanism of cytotoxic effect by some estrogens may involve modulation of the anti-apoptotic protein bcl-2. In the present study, we determined if LA had estrogenic activity, anti-tumor activity, and modulated the apoptotic protein bcl-2 in human cell lines derived from acute leukemia, breast cancer, and prostate cancer. A yeast growth-based assay under the control of the human estrogen receptor (hER) demonstrated that LA was a phytoestrogen. A cell viability assay demonstrated that LA had anti-tumor activity in all cell lines tested and enhanced the effect of paclitaxel and vinblastine chemotherapy. LA induced apoptosis in MCF-7 and HL-60 cell lines, as demonstrated by cleavage of PARP, the substrate of ICE-like proteases. Immunoblot analysis demonstrated that LA decreased the anti-apoptotic protein bcl-2 and altered the bcl-2/bax ratio in favor of apoptosis. In contrast, the parent compound chalcone or estradiol did not decrease bc1-2 expression. Therefore, these data demonstrate that LA is a phytoestrogen with anti-tumor activity and is capable of modulating bcl-2 protein expression. The modulation of bcl-2 may be dependent on specific structural differences between LA and the parent compound chalcone and independent of LA estrogenicity.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Chalcona/análogos & derivados , Estrogênios não Esteroides/farmacologia , Isoflavonas , Proteínas Proto-Oncogênicas c-bcl-2/análise , Apoptose/efeitos dos fármacos , Chalcona/farmacologia , Chalconas , Humanos , Fitoestrógenos , Preparações de Plantas , Proteínas Proto-Oncogênicas/análise , Células Tumorais Cultivadas , Leveduras/efeitos dos fármacos , Proteína X Associada a bcl-2
11.
J Agric Food Chem ; 47(12): 4880-2, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10606546

RESUMO

Two known glycosides and a novel trisaccharide fatty acid ester were isolated from the n-butanol-soluble fraction of the fruits of Morinda citrifolia (noni). Structure determination was carried out by spectral techniques such as MS, IR, NMR, and 2D-NMR. The novel trisaccharide fatty acid ester was elucidated as 2, 6-di-O-(beta-D-glucopyranosyl)-1-O-octanoyl-beta-D-glucopyranose. The known compounds were identified as rutin and asperulosidic acid.


Assuntos
Citrus/química , Ácidos Graxos/isolamento & purificação , Trissacarídeos/isolamento & purificação , Monoterpenos Ciclopentânicos , Ésteres , Ácidos Graxos/química , Glucosídeos/análise , Glucosídeos/química , Humanos , Espectroscopia de Ressonância Magnética , Piranos/análise , Piranos/química , Rutina/análise , Rutina/química , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria Infravermelho , Trissacarídeos/química
12.
J Med Chem ; 34(8): 2570-9, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1875349

RESUMO

A wide variety of 2-substituted aminoadenosines were prepared for comparison with the moderately A2 receptor selective adenosine agonist 2-anilinoadenosine (CV-1808). High selectivity combined with significant affinity at the A2 receptor in rat membranes was observed for those amines bearing a two-carbon chain to which was attached an aryl, heteroaryl, or alicyclic moiety. 2-(2-Phenethylamino)adenosine (3d), a 14-fold A2 selective compound, was modified by introduction of a variety of substituents in the benzene ring and the side chain. Some of these changes led to improved A2 affinity and increased selectivity. Replacement of the phenyl moiety by cyclohexenyl produced a 210-fold selective agonist 3ag (CGS 22989) whereas the cyclohexanyl analogue 3af (CGS 22492) was 530-fold selective at the A2 site. These compounds showed hypotensive activity in rat models over a range of doses without the bradycardia observed with less selective agonists.


Assuntos
Adenosina/análogos & derivados , Anti-Hipertensivos/síntese química , Receptores Purinérgicos/efeitos dos fármacos , Adenosina/síntese química , Adenosina/química , Adenosina/metabolismo , Adenosina/farmacologia , Adenosina/uso terapêutico , Alquilação , Animais , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Fenômenos Químicos , Química , Cicloexanos/síntese química , Cicloexanos/farmacologia , Cicloexanos/uso terapêutico , Frequência Cardíaca/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Masculino , Estrutura Molecular , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos , Receptores Purinérgicos/fisiologia
14.
J Med Chem ; 33(7): 1919-24, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2362269

RESUMO

The synthesis and receptor-binding profiles at adenosine receptor subtypes for a series of 2-(arylalkylamino)-adenosin-5'-uronamides is described. Halogenated 2-phenethylamino analogues such as 3e show greater than 200-fold selectivity for the A2 receptor subtype on the basis of rat brain receptor binding. The general structure-activity relationship of this series of compounds is discussed both in terms of potency at A2 receptors as well as receptor subtype selectivity. It is possible to introduce a hydrophilic carboxyalkyl substituent to this series such as in CGS 21680A (3h) and still retain good potency and selectivity for A2 receptors. In addition, functional data in a perfused working rat heart model shows that these compounds possess full agonist properties at A2 receptors with 3h having a greater than 1500-fold separation between A2 (coronary vasodilatory) and A1 (negative chronotropic) receptor mediated events.


Assuntos
Adenosina/análogos & derivados , Adenosina/síntese química , Receptores Purinérgicos/metabolismo , Adenosina/farmacologia , Animais , Encéfalo/metabolismo , Circulação Coronária/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Técnicas In Vitro , Indicadores e Reagentes , Ligantes , Espectroscopia de Ressonância Magnética , Masculino , Estrutura Molecular , Ratos , Ratos Endogâmicos , Relação Estrutura-Atividade , Vasodilatação/efeitos dos fármacos
15.
J Pharmacol Exp Ther ; 251(1): 47-55, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2795469

RESUMO

CGS 21680C (2-[p-(2-carboxyethyl)phenethylamino]-5'-N-ethyl-carboxamido adenosine) a 2-substituted analog of the riboside uronamide, 5'-N-ethylcarboxamido adenosine and the related analog CGS 21577 (2-phenethylamino-5'-N-ethylcarboxamido adenosine), have high in vitro affinity for brain striatal adenosine A2 receptors (IC50 values = 22 and 13 nM, respectively). Both compounds were considerably less active at A1 receptors with CGS 21577 and CGS 21680C having respective IC50 values of 0.76 and 3.1 microM. The former compound was thus 59-fold selective for A2 receptors whereas CGS 21680C was 140-fold selective. In contrast, the reference A2 selective ligand, CV 1808 (2-phenylaminoadenosine), showed only 8-fold selectivity as an A2 ligand, having an IC50 of 115 nM in the [3H]-5'N-ethylcarboxamide adenosine assay and an IC50 of 910 nM at the N6-[3H] cyclohexyladenosine site. Further examination of CGS 21680C showed that the compound was without effect on binding to 17 other putative neurotransmitter/neuromodulator sites indicating its selectivity as an adenosine receptor ligand. In an isolated perfused working rat heart model, CGS 21680C effectively increased coronary flow with an ED25 value of 1.8 nM. The corresponding value for CGS 21577 was 3 nM whereas that for CV 1808 was 110 nM. The EC25 for eliciting bradycardia for all three compounds was greater than 1000 nM. The effects of all three compounds could be reversed by treatment with the xanthine adenosine antagonist, xanthine amine congener.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Anti-Hipertensivos/farmacologia , Coração/efeitos dos fármacos , Fenetilaminas/farmacologia , Adenosina/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Técnicas In Vitro , Masculino , Ensaio Radioligante , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos , Receptores Purinérgicos/efeitos dos fármacos
16.
Artigo em Inglês | MEDLINE | ID: mdl-2526568

RESUMO

1. CGS 8515 selectively inhibited 5-LO (IC50 = 0.1 microM) with negligible effect on CO, 12-LO, 15-LO and TxS at concentrations up to 100 microM. 2. CGS 8515 selectively inhibited A23187-induced formation of 5-LO products in rat and human whole blood with a 20-70 fold separation of effects over the formation of CO products. 3. Ex vivo and in vivo studies with rats showed that CGS 8515, at an oral dose of 2-50 mg/kg, significantly inhibited A23187-induced formation of LTs in whole blood and in the lung. The effect persisted for at least 6 h in the ex vivo blood model. 4. CGS 8515, at oral doses as low as 5 mg/kg, significantly suppressed exudate volume and leukocyte migration in the carrageenan-induced pleurisy and sponge models in the rat.


Assuntos
Araquidonato 5-Lipoxigenase/sangue , Araquidonato Lipoxigenases/sangue , Leucócitos/enzimologia , Naftoquinonas/farmacologia , ortoaminobenzoatos/farmacologia , Animais , Ácidos Araquidônicos/sangue , Calcimicina/farmacologia , Movimento Celular , Humanos , Cinética , Leucócitos/efeitos dos fármacos , Leucócitos/fisiologia , Inibidores de Lipoxigenase , Ratos
17.
J Pharmacol Exp Ther ; 247(3): 882-8, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2849674

RESUMO

The activities of a series of A1 and A2 adenosine receptor agonists and antagonists were determined using radioligand binding techniques in rat brain tissues. The potencies of these agonists on heart rate and coronary vascular tone were also assessed in the perfused working rat heart preparation. The order of potency of these agonists in producing negative chronotropic effects was similar to the rank order for their A1 receptor binding activities [6-N-cyclohexyladenosine (CHA) = 6-N-(R-phenylisopropyl)-adenosine greater than 5'-N-ethylcarboxamideadenosine (NECA) = 2-chloroadenosine greater than 2-phenylaminoadenosine] with a correlation coefficient of 0.97. Their order of potency in reducing coronary vascular tone followed the same rank order as their A2 receptor binding activities with a correlation coefficient of 0.97 (NECA greater than 2-chloroadenosine = 6-N-(R-phenylisopropyl)-adenosine = 2-phenylaminoadenosine greater than CHA). In addition, the antagonists 8-[4-[[[[(2-aminoethyl)amino]carbonyl]methyl]ox]phenyl-1,3- dipropylxanthine (XAC), 1,3-dipropyl-8-(2-amino-4-chlorophenyl) xanthine (PACPX) and 8-phenyltheophylline (8-PT) blocked the negative chronotropic effect of CHA and the vasodilatory effect of NECA in a concentration-dependent manner. The same order of potency of the antagonists was noted in blocking CHA-induced bradycardia and A1 receptor binding activities (XAC = PACPX greater than 8-PT). A similar correlation was observed for their effects in blocking NECA-induced vasodilation and A2 receptor binding activity (XAC greater than PACPX greater than 8-PT).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Adenosina/farmacologia , Encéfalo/metabolismo , Vasos Coronários/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Receptores Purinérgicos/metabolismo , 3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Adenosina/antagonistas & inibidores , Adenosina/metabolismo , Animais , Circulação Coronária/efeitos dos fármacos , Relação Dose-Resposta a Droga , Técnicas In Vitro , Masculino , Ratos , Ratos Endogâmicos , Receptores Purinérgicos/efeitos dos fármacos
18.
Magn Reson Med ; 8(3): 340-4, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3205161

RESUMO

Glucose metabolism of human red blood cells was investigated using carbon-13 nuclear magnetic resonance spectroscopy under both oxygenated and nonoxygenated conditions. These results show that under oxygenated conditions reversal of 3-phosphoglyceraldehyde to glucose is in competition with its catabolism to lactate.


Assuntos
Glicemia/metabolismo , Eritrócitos/metabolismo , Espectroscopia de Ressonância Magnética , Humanos , Técnicas In Vitro , Oxigênio/fisiologia
19.
J Med Chem ; 31(5): 1014-20, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-3361572

RESUMO

During a search for benzodiazepine receptor modulators, a highly potent adenosine antagonist (CGS 15943) was discovered. The compound was defined as a resonance-stabilized hybrid of the canonical structures 9-chloro-2-(2-furyl)[1,2,4]triazolo[1,5-c]quinazolin-5-amine (2a) and 9-chloro-2-(2-furyl)-5,6-dihydro[1,2,4]triazolo[1,5-c]-quinazolin- 5-imine (2b). Spectroscopic evidence and chemical reactivity in polar media favor the amine form 2a as the major contributor of the two canonical structures. The synthesis of 2 and some of its analogues and the structure-activity relationships in four biological test systems are described. Replacement of the 9-chloro group by hydrogen, hydroxyl, or methoxyl gave compounds with comparable binding potency at the A1 and A2 receptors but much less activity as antagonists of 2-chloroadenosine in guinea pig tracheal strips. Alkylation of the 5-amino group caused, in general, a loss of binding activity, particularly at the A2 receptor, as well as complete loss of activity in the tracheal model. Modification of the 2-furyl group caused a pronounced loss of activity in all of the test systems.


Assuntos
Adenosina/antagonistas & inibidores , Quinazolinas/síntese química , Triazóis/síntese química , Animais , Fenômenos Químicos , Química , Cobaias , Técnicas In Vitro , Conformação Molecular , Músculo Liso/efeitos dos fármacos , Quinazolinas/farmacologia , Ratos , Receptores Purinérgicos/efeitos dos fármacos , Relação Estrutura-Atividade , Triazóis/farmacologia
20.
Biochim Biophys Acta ; 959(3): 332-42, 1988 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-2833314

RESUMO

CGS 8515 inhibited 5-hydroxyeicosatetraenoic acid (5-HETE) and leukotriene B4 synthesis in guinea pig leukocytes (IC50 = 0.1 microM). The compound did not appreciably affect cyclooxygenase (sheep seminal vesicles), 12-lipoxygenase (human platelets), 15-lipoxygenase (human leukocytes) and thromboxane synthetase (human platelets) at concentrations up to 100 microM. CGS 8515 inhibited A23187-induced formation of leukotriene products in whole blood (IC50 values of 0.8 and 4 microM, respectively, for human and rat) and in isolated rat lung (IC50 less than 1 microM) in vitro. The selectivity of the compound as a 5-lipoxygenase inhibitor was confirmed in rat whole blood by the 20-70-fold separation of inhibitory effects on the formation of leukotriene from prostaglandin products. Ex vivo and in vivo studies with rats showed that CGS 8515, at an oral dose of 2-50 mg/kg, significantly inhibited A23187-induced production of leukotrienes in whole blood and in the lung. The effect persisted for at least 6 h in the ex vivo whole blood model. CGS 8515, at oral doses as low as 5 mg/kg, significantly suppressed exudate volume and leukocyte migration in the carrageenan-induced pleurisy and sponge models in the rat. Inhibitory effects of the compound on inflammatory responses and leukotriene production in leukocytes and target organs are important parameters suggestive of its therapeutic potential in asthma, psoriasis and inflammatory conditions.


Assuntos
Araquidonato Lipoxigenases/antagonistas & inibidores , Benzoquinonas , Inibidores de Lipoxigenase , Naftoquinonas/farmacologia , ortoaminobenzoatos/farmacologia , Animais , Ácido Araquidônico , Ácidos Araquidônicos/metabolismo , Biotransformação , Plaquetas/efeitos dos fármacos , Plaquetas/enzimologia , Calcimicina/farmacologia , Dexametasona/farmacologia , Cobaias , Humanos , Ácidos Hidroxieicosatetraenoicos/biossíntese , Indometacina/farmacologia , Leucócitos/efeitos dos fármacos , Leucotrieno B4/biossíntese , Masculino , Pleurisia/enzimologia , Quinonas/farmacologia , Ratos , Ratos Endogâmicos , Ovinos
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