Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
J Food Biochem ; 46(3): e13999, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34747031

RESUMO

A new rutin copper(II) complex (R-Cu2) was prepared and characterized by spectroscopic methods and elemental analysis. The effects of rutin and R-Cu2 were evaluated on the prevention of hypercholesterolemia in animals feed with high-cholesterol diet (HCD) for 8 weeks. The animals (n = 5) were neither fed with HCD nor treated (control group), or were treated with vehicle, 10 mg/kg simvastatin, rutin (16 and 160 µmol/kg), and R-Cu2 (16 and 160 µmol/kg) administered orally. Total cholesterol (TC) levels were significantly increased (p < .01) in all HCD groups. In rutin and R-Cu2 groups, it was observed a discrete, but not significant, TC and LDL-induced increase inhibition compared with vehicle-treated group. R-Cu2 treatment significantly decreased (p < .05) plasma triglycerides compared with the vehicle-treated group. All groups receiving treatments maintained the malondialdehyde at normal levels. Serum NO levels were reduced in animals treated with rutin and R-Cu2 compared with the vehicle-treated group. In addition, the results also showed that the groups treated with rutin and R-Cu2 reduced significantly (p < .01), the number of neutrophils and prevented histological changes in all evaluated liver zones. R-Cu2 group maintained the ALT, AST, and ALP enzymes at normal levels. Thus, the effects of R-Cu2 in modulating inflammation and protecting liver damage were confirmed. PRACTICAL APPLICATIONS: Rutin, a plant-derived flavonoid, is one of phenolic compounds well known as a nutraceutical due to its antioxidant and anti-inflammatory properties. Findings of this study demonstrate the effects of both rutin and R-Cu2 in modulating inflammation and protecting liver damage in hypercholesterolemic rats. However, some effects analyzed became more evident in R-Cu2. Thereby, it was shown that the synthesis of a new flavonoid compound (R-Cu2) could be applied as a nutraceutical benefit option to prevent hypercholesterolemia condition.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Hipercolesterolemia , Hepatopatias , Animais , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Colesterol , Hipercolesterolemia/tratamento farmacológico , Inflamação , Peroxidação de Lipídeos , Ratos , Rutina/farmacologia
2.
Braz. j. otorhinolaryngol. (Impr.) ; 86(6): 734-742, Nov.-Dec. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1142590

RESUMO

Abstract Introduction: Tinnitus is defined as the perception of sound without its actual presence in the environment. It has been the subject of a great number of studies, especially considering its consequences on patient's quality of life. Objective: This study aimed to investigate the effect of hearing aids and/or Ginkgo biloba extract EGb 761 on tinnitus in patients with hearing loss. Methods: This is a trial randomized-controlled treatment, parallel, double-blind, with three-arm. Thirty-three adults subjects were divided into three groups: group 1 — subjects undergoing drug therapy with Ginkgo biloba extract EGb 761; group 2 — individuals fitted with digital hearing aids; group 3 — individuals submitted to drug therapy with Ginkgo biloba extract EGb 761 and using hearing aids. The tinnitus handicap inventory and visual analogue scale were used to evaluate self-perception of tinnitus loudness and severity before treatment and 90 days after treatment. Results: This study demonstrated a significant correlation between tinnitus handicap inventory and visual analogue scale, before and after treatment. We observed a significant improvement in self-perception of tinnitus loudness and severity after 90 days of treatment with Ginkgo biloba extract EGb 761 and/or hearing aids. No correlation was found between tinnitus onset time and self-perception of tinnitus loudness and severity. Hearing aids were more effective in patients with a shorter tinnitus onset time and Ginkgo biloba extract was effective regardless of tinnitus duration. Conclusions: It was possible to prove the effectiveness of the hearing aids and/or Ginkgo biloba extract EGb 761 treatment, which shows success in the control of tinnitus contributing to the improvement of this symptom.


Resumo Introdução: O zumbido é definido como a percepção de um som sem a sua presença real no ambiente e tem sido objeto de um grande número de estudos, especialmente devido às suas consequências na qualidade de vida do paciente. Objetivo: Investigar o efeito de próteses auditivas e/ou extrato de Ginkgo biloba EGb 761 sobre o zumbido em pacientes com perda auditiva. Método: Ensaio clínico randomizado controlado, paralelo, duplo-cego, com três braços. Trinta e três indivíduos adultos foram divididos em três grupos: Grupo 1 - indivíduos submetidos à terapia medicamentosa com extrato de Ginkgo biloba EGb 761; Grupo 2 - indivíduos equipados com próteses auditivas digitais; Grupo 3 - indivíduos submetidos à terapia medicamentosa com extrato de Ginkgo biloba EGb 761 e próteses auditivas. O Tinnitus handicap inventory e a escala visual analógica foram usados para avaliar a autopercepção de intensidade e da gravidade do zumbido antes do tratamento e 90 dias após o tratamento. Resultados: Este estudo demonstrou uma correlação significante entre o Tinnitus handicap inventory e a escala visual analógica, antes e após o tratamento. Observou-se melhoria significativa na autopercepção de loudness e da intensidade do zumbido após 90 dias de tratamento com extrato de Ginkgo biloba EGb 761 e/ou prótese auditiva. Não foi encontrada correlação entre o tempo de início do zumbido e a autopercepção da intensidade e gravidade do zumbido. As próteses auditivas foram mais eficazes em pacientes com menor tempo de início de zumbido e o extrato de Ginkgo biloba foi eficaz, independentemente da duração do zumbido. Conclusões: Foi possível comprovar a eficácia do tratamento com a prótese auditiva e/ou extrato de Ginkgo biloba EGb 761, o que demonstra sucesso no controle do zumbido e contribui para a melhoria desse sintoma.


Assuntos
Humanos , Zumbido/tratamento farmacológico , Auxiliares de Audição , Qualidade de Vida , Extratos Vegetais , Método Duplo-Cego , Ginkgo biloba
3.
Braz J Otorhinolaryngol ; 86(6): 734-742, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31300303

RESUMO

INTRODUCTION: Tinnitus is defined as the perception of sound without its actual presence in the environment. It has been the subject of a great number of studies, especially considering its consequences on patient's quality of life. OBJECTIVE: This study aimed to investigate the effect of hearing aids and/or Ginkgo biloba extract EGb 761 on tinnitus in patients with hearing loss. METHODS: This is a trial randomized-controlled treatment, parallel, double-blind, with three-arm. Thirty-three adults subjects were divided into three groups: group 1 - subjects undergoing drug therapy with Ginkgo biloba extract EGb 761; group 2 - individuals fitted with digital hearing aids; group 3 - individuals submitted to drug therapy with Ginkgo biloba extract EGb 761 and using hearing aids. The tinnitus handicap inventory and visual analogue scale were used to evaluate self-perception of tinnitus loudness and severity before treatment and 90 days after treatment. RESULTS: This study demonstrated a significant correlation between tinnitus handicap inventory and visual analogue scale, before and after treatment. We observed a significant improvement in self-perception of tinnitus loudness and severity after 90 days of treatment with Ginkgo biloba extract EGb 761 and/or hearing aids. No correlation was found between tinnitus onset time and self-perception of tinnitus loudness and severity. Hearing aids were more effective in patients with a shorter tinnitus onset time and Ginkgo biloba extract was effective regardless of tinnitus duration. CONCLUSIONS: It was possible to prove the effectiveness of the hearing aids and/or Ginkgo biloba extract EGb 761 treatment, which shows success in the control of tinnitus contributing to the improvement of this symptom.


Assuntos
Auxiliares de Audição , Zumbido , Método Duplo-Cego , Ginkgo biloba , Humanos , Extratos Vegetais , Qualidade de Vida , Zumbido/tratamento farmacológico
4.
Eur J Pharmacol ; 591(1-3): 189-95, 2008 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-18593576

RESUMO

Nitrergic nerves and endothelial cells release nitric oxide (NO) in the corpus cavernosum, a key mediator that stimulates soluble guanylyl cyclase to increase cGMP levels causing penile erection. Phosphodiesterase 5 (PDE5) inhibitors, such as sildenafil, prolong the NO effects by inhibiting cGMP breakdown. Here, we report a novel PDE5 inhibitor, lodenafil carbonate, (Bis-(2-{4-[4-ethoxy-3-(1-methyl-7-oxo-3-propyl-6,7-dihydro-1H-pyrazolo[4,3-d]pyrimidin-5-yl)-benzenesulfonyl]piperazin-1-yl}-ethyl)carbonate) that is a dimer of lodenafil. We therefore aimed to compare the effects of sildenafil, lodenafil and lodenafil carbonate on in vitro human and rabbit cavernosal relaxations, activity of crude PDE extracts from human platelets, as well as stability and metabolic studies in rat, dog and human plasma. Pharmacokinetic evaluations after intravenous and oral administration were performed in male beagles. Functional experiments were conducted using organ bath techniques. Pharmacokinetics was studied in beagles by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), following oral or intravascular administration. All PDE5 inhibitors tested concentration-dependently relaxed (0.001-100 microM) phenylephrine-precontracted rabbit and human corpus cavernosum. The cavernosal relaxations evoked by either acetylcholine (0.01-100 microM) or electrical field stimulation (EFS, 1-20 Hz) were markedly potentiated by sildenafil, lodenafil and lodenafil carbonate. Lodenafil carbonate was more potent to inhibit the cGMP hydrolysis in PDE extracts compared with lodenafil and sildenafil. Following intravascular and single oral administration of lodenafil carbonate, only lodenafil and norlodenafil were detected in vivo. These results indicate that lodenafil carbonate works as a prodrug, being lodenafil the active moiety of lodenafil carbonate.


Assuntos
Carbonatos/farmacologia , Disfunção Erétil/tratamento farmacológico , Pênis/efeitos dos fármacos , Inibidores de Fosfodiesterase/farmacologia , Piperazinas/farmacologia , Pirimidinas/farmacologia , Administração Oral , Adulto , Animais , Carbonatos/administração & dosagem , Carbonatos/farmacocinética , Cromatografia Líquida , GMP Cíclico/metabolismo , Cães , Relação Dose-Resposta a Droga , Estabilidade de Medicamentos , Estimulação Elétrica , Humanos , Injeções Intravenosas , Masculino , Pênis/metabolismo , Inibidores de Fosfodiesterase/administração & dosagem , Inibidores de Fosfodiesterase/farmacocinética , Piperazinas/administração & dosagem , Piperazinas/farmacocinética , Pró-Fármacos , Purinas/farmacologia , Pirimidinas/administração & dosagem , Pirimidinas/farmacocinética , Coelhos , Ratos , Citrato de Sildenafila , Sulfonas/farmacologia , Espectrometria de Massas em Tandem
5.
Arch Pharm (Weinheim) ; 340(9): 445-55, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17763375

RESUMO

We report microwave-assisted synthetic routes, the pharmacokinetic profile along with results from ulcerogenicity and mutagenicity studies of atenolol aspirinate, and an already described derivative, in which acetyl salicylic acid (aspirin) was connected to atenolol by an ester linkage. Atenolol aspirinate was stable towards aqueous hydrolysis but rapidly hydrolyzed in plasma (t(1/2) = 7.6 min). The results showed that the rapid and complete hydrolysis generates atenolol salicylate, which assumes a conformation stabilized by two intramolecular H-bonds, avoiding its further hydrolysis to salicylic acid and atenolol.


Assuntos
Anti-Hipertensivos/farmacocinética , Aspirina/química , Atenolol/farmacocinética , Animais , Anti-Hipertensivos/química , Anti-Hipertensivos/metabolismo , Área Sob a Curva , Atenolol/química , Atenolol/metabolismo , Mucosa Gástrica/efeitos dos fármacos , Meia-Vida , Humanos , Micro-Ondas , Modelos Moleculares , Testes de Mutagenicidade , Pró-Fármacos/química , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacocinética
6.
Clin Exp Pharmacol Physiol ; 34(4): 290-5, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17324140

RESUMO

1. Pharmacological compounds that release nitric oxide (NO) have been useful tools in the evaluation of the broad role of NO in physiopathology and therapeutics. The present study compared the pharmacokinetics and pharmacodynamics of enalapril and an NO-releasing enalapril molecule (NCX899) in conscious male beagles. The effects of both enalapril and NCX899 in the arterial hypertension and bradycardia induced by acute NO inhibition in anaesthetized dogs were also investigated. 2. Dogs received either NCX899 (4 micromol/kg, i.v.) or enalapril (4 micromol/kg, i.v.), after which plasma concentrations of the analytes and metabolites were quantified by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). 3. In the NCX899 group, the area under the time-course curve (AUC(0-24h)) was 29.18 +/- 4.72, 229.37 +/- 51.32 and 5159.23 +/- 514.88 microg.h/L for the analytes nitro-enalapril, enalapril and enalaprilat, respectively. In the enalapril group, the AUC(0-24h) was 704.53 +/- 158.86 and 4149.27 +/- 847.30 microg.h/L for the analytes enalapril and enalaprilat, respectively. Statistical analysis of data from both groups showed a significant difference for the analyte enalapril, but not for enalaprilat. Moreover, NCX899 and enalapril were equally effective in inhibiting the activity of serum angiotensin-converting enzyme. 4. In anaesthetized dogs, i.v. administration of the NO synthase (NOS) inhibitor N(G)-nitro-l-arginine methyl ester (l-NAME; 0.1-10 mg/kg) significantly elevated arterial blood pressure, with concomitant bradycardia. The compound NCX899 significantly attenuated both arterial hypertension and bradycardia, whereas enalapril had no significant effect. 5. In conclusion, the present results showed that the NO-releasing derivative of enalapril NCX899 presents a pharmacokinetic/pharmacodynamic relationship similar to its parent compound enalapril. Moreover, NCX899 (but not enalapril) was effective in protecting against the cardiovascular changes induced by acute NOS inhibition.


Assuntos
Enalapril/farmacocinética , Doadores de Óxido Nítrico/farmacocinética , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/metabolismo , Inibidores da Enzima Conversora de Angiotensina/farmacocinética , Animais , Área Sob a Curva , Pressão Sanguínea/efeitos dos fármacos , Cromatografia Líquida , Cães , Relação Dose-Resposta a Droga , Enalapril/administração & dosagem , Enalapril/análogos & derivados , Enalapril/química , Enalaprilato/metabolismo , Inibidores Enzimáticos/farmacologia , Meia-Vida , Frequência Cardíaca/efeitos dos fármacos , Concentração Inibidora 50 , Injeções Intravenosas , Masculino , Estrutura Molecular , NG-Nitroarginina Metil Éster/farmacologia , Doadores de Óxido Nítrico/administração & dosagem , Doadores de Óxido Nítrico/sangue , Espectrometria de Massas em Tandem , Fatores de Tempo
7.
Urology ; 63(1): 184-9, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14751389

RESUMO

OBJECTIVES: To investigate the effects of a purified scorpion toxin (Ts3) on human corpus cavernosum (HCC) in vitro. Scorpion venoms cause a massive release of neurotransmitters that contribute to the clinical symptoms resulting from envenomation. METHODS: HCC strips were mounted in organ baths containing Krebs solution. After equilibration, the tissues were precontracted with phenylephrine (10 micromol/L). The relaxations caused by Ts3 (30 nmol/L) were compared with those induced by electrical field stimulation (1 to 20 Hz) and nitric oxide (NO, 1 to 100 micromol/L). RESULTS: The addition of Ts3 evoked long-lasting relaxations of precontracted HCC strips, and exogenously applied NO and electrical field stimulation caused short-lived responses. The NO synthesis inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME; 100 micromol/L) reduced by 87% +/- 2% the Ts3-induced relaxations; this inhibition was reversed by pretreating the tissues with L-arginine (1 mmol/L). The relaxant responses mediated by Ts3 were blocked to a similar degree by the soluble guanylyl cyclase inhibitor 1H-[1,2,4] oxadiazolo [4,3,-alquinoxalin-1-one] (10 micromol/L). In contrast, the addition of the phosphodiesterase type 5 inhibitor sildenafil (0.1 micromol/L) significantly enhanced Ts3-evoked relaxations by 78% +/- 4%. The sodium channel blocker tetrodotoxin (1 micromol/L) completely blocked the relaxant responses elicited by both Ts3 and electrical field stimulation, without significantly affecting those elicited by NO. CONCLUSIONS: The results indicate that Ts3 relaxes the HCC through the release of NO from nitrergic nerves. The elucidation of this mechanism is useful for the development of new therapeutic strategies to treat priapism after scorpion envenomation or to modulate sodium channel activity in the case of penile dysfunction.


Assuntos
Neurotoxinas/farmacologia , Óxido Nítrico/metabolismo , Pênis/efeitos dos fármacos , Venenos de Escorpião/farmacologia , Adolescente , Adulto , Criança , GMP Cíclico/fisiologia , Avaliação Pré-Clínica de Medicamentos , Estimulação Elétrica , Inibidores Enzimáticos/farmacologia , Humanos , Técnicas In Vitro , Masculino , Contração Muscular/efeitos dos fármacos , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/farmacologia , Óxido Nítrico/fisiologia , Oxidiazóis/farmacologia , Pênis/metabolismo , Fenilefrina/farmacologia , Piperazinas/farmacologia , Priapismo/tratamento farmacológico , Purinas , Quinoxalinas/farmacologia , Sistemas do Segundo Mensageiro/fisiologia , Citrato de Sildenafila , Bloqueadores dos Canais de Sódio/farmacologia , Sulfonas , Tetrodotoxina/farmacologia
8.
Toxicon ; 42(5): 451-60, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14529726

RESUMO

Scorpion venoms are known to cause peripheral nerve stimulation with enhanced autonomic responses. This study, therefore, examined the effects of Tityus serrulatus venom (TSV) on adrenergic, cholinergic and nitrergic nerve fibers using the rat anococcygeus muscle. The contractile effects of TSV (1 microg/ml) and electrical field stimulation were markedly reduced by phentolamine (5 microM), prazosin (0.1 microM), guanethidine (30 microM) and tetrodotoxin (TTX, 1 microM), whereas imipramine (3 microM) enhanced these responses. The responses to tyramine (10 microM) were partially reduced by guanethidine and completely blocked by phentolamine, prazosin and imipramine. Atropine (1 microM) fully prevented carbachol (CCh, 30 microM)-induced contractions without affecting those mediated by TSV. Neostigmine significantly potentiated TSV-and ACh-evoked contractions, whereas hexamethonium had no effect. The relaxant responses induced by EFS and TSV (3 microg/ml) were completely blocked by L-NAME (100 microM), ODQ (1 microM) or TTX (1 microM). Addition of L-arginine (1 mM) reversed the effect of L-NAME. Thus, the motor and inhibitory responses of TSV in the rat anococcygeus muscle are mediated by prejunctional mechanisms dependent on Na(+) channel activation, causing the stimulation of NA and NO release from adrenergic and nitrergic nerve fibers, respectively.


Assuntos
Músculo Esquelético/efeitos dos fármacos , Terminações Pré-Sinápticas/efeitos dos fármacos , Venenos de Escorpião/farmacologia , Antagonistas Adrenérgicos alfa/farmacologia , Animais , Atropina/farmacologia , Carbacol/farmacologia , Antagonistas Colinérgicos/farmacologia , Estimulação Elétrica , Guanetidina/farmacologia , Imipramina/farmacologia , Masculino , Antagonistas Muscarínicos/farmacologia , Contração Muscular/efeitos dos fármacos , Neurônios Nitrérgicos/efeitos dos fármacos , Fentolamina/farmacologia , Prazosina/farmacologia , Ratos , Ratos Wistar , Venenos de Escorpião/antagonistas & inibidores , Escorpiões , Tetrodotoxina/farmacologia , Tiramina/farmacologia
9.
Eur J Pharmacol ; 477(2): 163-9, 2003 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-14519420

RESUMO

5-Cyclopropyl-2-[1-(2-fluoro-benzyl)-1H-pyrazolo[3,4-b]pyridin-3-yl]-pyrimidin-4-ylamine (BAY 41-2272) is a potent soluble guanylyl cyclase stimulator in a nitric oxide (NO)-independent manner. The relaxant effect of BAY 41-2272 was investigated in rabbit and human corpus cavernosum in vitro. BAY 41-2272 (0.01-10 microM) relaxed both rabbit (pEC(50)=6.82+/-0.06) and human (pEC(50)=6.12+/-0.10) precontracted cavernosal strips. The guanylyl cyclase inhibitor (ODQ, 10 microM) caused significant rightward shifts in the concentration-response curves for BAY 41-2272 in rabbit (4.7-fold) and human (2.3-fold) tissues. The NO synthesis inhibitor (N-nitro-L-arginine methyl ester (L-NAME), 100 microM) also produced similar rightward shifts, revealing that BAY 41-2272 acts synergistically with endogenous NO to elicit its relaxant effect. The results also indicate that ODQ is selective for the NO-stimulated enzyme, since relaxations evoked by BAY 41-2272 were only partly attenuated by ODQ. The present study shows that both BAY 41-2272 and sildenafil evoke relaxations independent of inhibition of haem in soluble guanylate cyclase. Moreover, there is no synergistic effect of the two compounds in corpus cavernosum.


Assuntos
Ativadores de Enzimas/farmacologia , Guanilato Ciclase/metabolismo , Pênis/efeitos dos fármacos , Pirazóis/farmacologia , Piridinas/farmacologia , Adolescente , Adulto , Idoso , Animais , AMP Cíclico/metabolismo , Sinergismo Farmacológico , Guanilato Ciclase/antagonistas & inibidores , Humanos , Técnicas In Vitro , Contração Isométrica/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Relaxamento Muscular/efeitos dos fármacos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Oxidiazóis/farmacologia , Pênis/fisiologia , Coelhos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA