RESUMO
In this study, we investigated the influence of mixture design on the chemical profile of Eugenia unifloraleaves, evaluating the antioxidant and antimicrobial activities, the toxic and hemolytic potential, with the focus on the improvement of the polyphenol's extraction for incorporation of the extract in semi-solid forms with antifungal action. The chemical analysis was evaluated by UV-Vis and HPLC. The antimicrobial, antioxidant, and hemolytic activities were monitored. The flavonoid content ranged from 2.63-7.98 %w/w and tannins from 5.42-18.29 %w/w. The extract consisted of gallic acid (0.09-1.29%; w/w), ellagic acid (0.09-0.37%; w/w), and myricitrin (0.18-1.20%; w/w). The most successful solvent system with the highest level of active extract was water: ethanol: propylene glycol. The extracts showed fungicidal properties (3.9 µg/mL), high antioxidant activity (IC50: 9.50 µg/mL), and low toxicity. These solvent mixtures can improve the in vitro bioactivities when compared to pure solvents and this result demonstrates the importance of mixture designs as useful tools for creating high-quality herbal products and elucidate the potential of E. uniflora glycolic extracts as active herbal pharmaceutical ingredients in topical delivery systems.
En este estudio investigamos la influencia del diseño de mezclas en el perfil químico de hojas de Eugenia uniflora, evaluando las actividades antioxidantes y antimicrobianas, el potencial tóxico y hemolítico, con el foco en la mejora de la extracción de polifenoles para la incorporación del extracto en formas semi-sólidas con acción antifúngica. El análisis químico se evaluó mediante UV-Vis y HPLC. Se monitorizaron las actividades antimicrobianas, antioxidantes y hemolíticas. El contenido de flavonoides osciló entre 2,63 y 7,98% p/p and taninos de 5,42-18,29% p/p. El extracto consistió en ácido gálico (0.09-1.29%; p/p), ácido elágico (0.09-0.37%; p/p) y miricitrina (0.18-1.20%; p/p). El sistema de disolventes más exitoso con el nivel más alto de extracto activo fue agua: etanol: propilenglicol. Los extractos mostraron propiedades fungicidas (3.9 µg/mL), alta actividad antioxidante (IC50: 9.50 µg/mL) y baja toxicidad. Estas mezclas de disolventes pueden mejorar las bioactividades in vitro en comparación con los disolventes puros y este resultado demuestra la importancia de los diseños de mezclas como herramientas útiles para crear productos a base de hierbas de alta calidad y dilucidar el potencial de los extractos glicólicos de E. uniflora como ingredientes farmacéuticos a base de hierbas en sistemas de entrega activos.
Assuntos
Extratos Vegetais/química , Eugenia/química , Anti-Infecciosos/química , Espectrofotometria/métodos , Taninos/análise , Bactérias/efeitos dos fármacos , Flavonoides/análise , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana , Análise de Variância , Cromatografia Líquida de Alta Pressão , Hemolíticos , Compostos Fitoquímicos , Fungos/efeitos dos fármacos , Anti-Infecciosos/toxicidade , Anti-Infecciosos/farmacologia , AntioxidantesRESUMO
The new pathway nitrate-nitrite-nitric oxide (NO) has emerged as a physiological alternative to the classical enzymatic pathway for NO formation from l-arginine. Nitrate is converted to nitrite by commensal bacteria in the oral cavity and the nitrite formed is then swallowed and reduced to NO under the acidic conditions of the stomach. In this study, we tested the hypothesis that increases in gastric pH caused by omeprazole could decrease the hypotensive effect of oral sodium nitrite. We assessed the effects of omeprazole treatment on the acute hypotensive effects produced by sodium nitrite in normotensive and L-NAME-hypertensive free-moving rats. In addition, we assessed the changes in gastric pH and plasma levels of nitrite, NO(x) (nitrate+nitrite), and S-nitrosothiols caused by treatments. We found that the increases in gastric pH induced by omeprazole significantly reduced the hypotensive effects of sodium nitrite in both normotensive and L-NAME-hypertensive rats. This effect of omeprazole was associated with no significant differences in plasma nitrite, NO(x), or S-nitrosothiol levels. Our results suggest that part of the hypotensive effects of oral sodium nitrite may be due to its conversion to NO in the acidified environment of the stomach. The increase in gastric pH induced by treatment with omeprazole blunts part of the beneficial cardiovascular effects of dietary nitrate and nitrite.
Assuntos
Anti-Hipertensivos/administração & dosagem , Suco Gástrico/química , Nitrito de Sódio/administração & dosagem , Administração Oral , Animais , Antiulcerosos/farmacologia , Anti-Hipertensivos/antagonistas & inibidores , Aorta/efeitos dos fármacos , Aorta/fisiopatologia , Benzoatos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Suco Gástrico/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Hipertensão/induzido quimicamente , Hipertensão/tratamento farmacológico , Imidazóis/farmacologia , Técnicas In Vitro , Masculino , NG-Nitroarginina Metil Éster , Óxido Nítrico/sangue , Omeprazol/farmacologia , Ratos , Ratos Wistar , S-Nitrosotióis/sangue , Nitrito de Sódio/antagonistas & inibidores , Vasodilatação/efeitos dos fármacosRESUMO
Hypertension induces vascular alterations that are associated with up-regulation of matrix metalloproteinases (MMPs). While these alterations may be blunted by doxycycline, a non-selective MMPs inhibitor, no previous study has examined the effects of different doses of doxycycline on these alterations. This is important because doxycycline has been used at sub-antimicrobial doses, and the use of lower doses may prevent the emergence of antibiotic-resistant microorganisms. We studied the effects of doxycycline at 3, 10 and 30 mg/kg per day on the vascular alterations found in the rat two kidney-one clip (2K1C) hypertension (n = 20 rats/group). Systolic blood pressure (SBP) was monitored during 4 weeks of treatment. We assessed endothelium-dependent and independent relaxations. Quantitative morphometry of structural changes in the aortic wall was studied, and aortic MMP-2 levels/proteolytic activity were determined by gelatin and in situ zymography, respectively. All treatments attenuated the increases in SBP in hypertensive rats (195.4 ± 3.9 versus 177.2 ± 6.2, 176.3 ± 4.5, and 173 ± 5.1 mmHg in 2K1C hypertensive rats treated with vehicle, or doxycycline at 3, 10, 30 mg/kg per day, respectively (all p < 0.01). However, only the highest dose prevented 2K1C-induced reduction in endothelium-dependent vasorelaxation (p < 0.05), vascular hypertrophy and increases in MMP-2 levels (all p < 0.05). In conclusion, our results suggest that relatively lower doses of doxycycline do not attenuate the vascular alterations found in the 2K1C hypertension model, and only the highest dose of doxycycline affects MMPs and vascular structure. Our results support the idea that the effects of doxycycline on MMP-2 and vascular structure are pressure independent.
Assuntos
Sistema Cardiovascular/efeitos dos fármacos , Sistema Cardiovascular/enzimologia , Doxiciclina/farmacologia , Inibidores Enzimáticos/farmacologia , Hipertensão/metabolismo , Metaloproteinases da Matriz/metabolismo , Análise de Variância , Animais , Aorta/metabolismo , Aorta/patologia , Pressão Sanguínea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Hipertensão/patologia , Masculino , Inibidores de Metaloproteinases de Matriz , Ratos , Ratos Wistar , Regulação para Cima , VasodilataçãoRESUMO
INTRODUCTION: Inhibition of matrix metalloproteinases (MMPs) improves the hemodynamics during acute pulmonary embolism (APE) and oxidative stress upregulates MMPs. We compared the effects of different NO-cGMP pathway activators on APE-induced increases in MMPs. MATERIALS AND METHODS: Hemodynamic and biochemical evaluations were performed in non-embolized dogs treated with saline (N=5), and in microspheres embolized dogs receiving saline (n=9), or nitrite (6.75 micromol/kg i.v. over 15 min followed by 0.28 micromol/kg/min; n=5), or sildenafil (0.25 mg/kg; n=5), or BAY 41-2272 (0.03, 0.1, 0.3, and 1 mg/kg/h; n=5). Plasma thiobarbituric acid reactive substances (TBARS) concentrations were determined. Zymograms of plasma samples were performed, and in vitro antioxidant effects or inhibition of MMPs by these drugs were examined. RESULTS: APE increased mean pulmonary artery pressure by ~25 mmHg. Nitrite, BAY 41-2272, or sildenafil reversed this increase by ~40% (P<0.05). Similar effects were seen on the pulmonary vascular resistance. While both nitrite and sildenafil produced no systemic effects, the highest dose of BAY 41-2272 produced systemic hypotension (P<0.05). While nitrite and sildenafil blunted the increases in plasma pro-MMP-9 levels and TBARS (all P<0.05), BAY 41-2272 produced no such effects. Nitrite and sildenafil produced in vitro antioxidant effects and inhibited MMPs only at high concentrations. BAY 41-2272 produced no such effects. CONCLUSIONS: Activation of the NO-cGMP pathway with nitrite or sildenafil, but not with BAY 41-2272, attenuates APE-induced oxidative stress and increased MMP-9 levels. These findings are consistent with the idea that NO-cGMP pathway activators with antioxidant effects prevent the release of MMP-9 during APE.